Sample records for sunflower seed dormancy
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Response of sunflower to various pre-germination techniques for breaking seed dormancy
International Nuclear Information System (INIS)
Nasreen, S.; Khan, M.A.; Uddin, S.
2015-01-01
Seed dormancy is considered to be a serious constraint in sunflower seed production. Viable seeds sometimes do not germinate even in the presence of favorable environmental conditions. Such seeds are suspected to be dormant. The study was conducted under controlled/laboratory conditions during spring 2010 at National Agricultural Research Centre, Islamabad. The objective of the study was to evaluate some techniques to convert a seed from dormant to non-dormant germinable state. Dormant seeds of 21 sunflower hybrids were treated with three hot water treatments (100/80 degree C) and four chemicals potassium nitrate, 0.2%, thiourea, 0.5%, ethanol, 25%, acetone, 25% for breaking seed dormancy .The untreated seed was taken as control. Soaking seeds in hot water (80 degree C) for 15 minutes followed by one day dry and seed treatment with acetone were found to be the most effective and successful techniques in converting the seed from dormant to non-dormant state. (author)
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Seed dormancy and germination.
Penfield, Steven
2017-09-11
Reproduction is a critical time in plant life history. Therefore, genes affecting seed dormancy and germination are among those under strongest selection in natural plant populations. Germination terminates seed dispersal and thus influences the location and timing of plant growth. After seed shedding, germination can be prevented by a property known as seed dormancy. In practise, seeds are rarely either dormant or non-dormant, but seeds whose dormancy-inducing pathways are activated to higher levels will germinate in an ever-narrower range of environments. Thus, measurements of dormancy must always be accompanied by analysis of environmental contexts in which phenotypes or behaviours are described. At its simplest, dormancy can be imposed by the formation of a simple physical barrier around the seed through which gas exchange and the passage of water are prevented. Seeds featuring this so-called 'physical dormancy' often require either scarification or passage through an animal gut (replete with its associated digestive enzymes) to disrupt the barrier and permit germination. In other types of seeds with 'morphological dormancy' the embryo remains under-developed at maturity and a dormant phase exists as the embryo continues its growth post-shedding, eventually breaking through the surrounding tissues. By far, the majority of seeds exhibit 'physiological dormancy' - a quiescence program initiated by either the embryo or the surrounding endosperm tissues. Physiological dormancy uses germination-inhibiting hormones to prevent germination in the absence of the specific environmental triggers that promote germination. During and after germination, early seedling growth is supported by catabolism of stored reserves of protein, oil or starch accumulated during seed maturation. These reserves support cell expansion, chloroplast development and root growth until photoauxotrophic growth can be resumed. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Grappin, P; Bouinot, D; Sotta, B; Miginiac, E; Jullien, M
2000-01-01
The physiological characteristics of seed dormancy in Nicotiana plumbaginifolia Viv. are described. The level of seed dormancy is defined by the delay in seed germination (i.e the time required prior to germination) under favourable environmental conditions. A wild-type line shows a clear primary dormancy, which is suppressed by afterripening, whereas an abscisic acid (ABA)-deficient mutant shows a non-dormant phenotype. We have investigated the role of ABA and gibberellic acid (GA(3)) in the control of dormancy maintenance or breakage during imbibition in suitable conditions. It was found that fluridone, a carotenoid biosynthesis inhibitor, is almost as efficient as GA(3) in breaking dormancy. Dry dormant seeds contained more ABA than dry afterripened seeds and, during early imbibition, there was an accumulation of ABA in dormant seeds, but not in afterripened seeds. In addition, fluridone and exogenous GA(3) inhibited the accumulation of ABA in imbibed dormant seeds. This reveals an important role for ABA synthesis in dormancy maintenance in imbibed seeds.
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Seed dormancy and seed longevity: from genetic variation to gene identification
Nguyen, T.P.
2014-01-01
Seed dormancy and seed longevity are the most important survival traits in the soil seed bank. Both traits are induced during seed maturation and evolved to assure seed survival during environmental conditions that cannot support the regular course of life. Seed dormancy is related to the timing of
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Ukleja-Sokołowska, Natalia; Gawrońska-Ukleja, Ewa; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew; Sokołowski, Łukasz
2016-01-01
Sunflower seeds are a rare source of allergy, but several cases of occupational allergies to sunflowers have been described. Sunflower allergens on the whole, however, still await precise and systematic description. We present an interesting case of a 40-year-old male patient, admitted to hospital due to shortness of breath and urticaria, both of which appeared shortly after the patient ingested sunflower seeds. Our laryngological examination revealed swelling of the pharynx with retention of saliva and swelling of the mouth and tongue. During diagnostics, 2 months later, we found that skin prick tests were positive to mugwort pollen (12/9 mm), oranges (6/6 mm), egg protein (3/3 mm), and hazelnuts (3/3 mm). A native prick by prick test with sunflower seeds was strongly positive (8/5 mm). Elevated concentrations of specific IgE against weed mix (inc. lenscale, mugwort, ragweed) allergens (1.04 IU/mL), Artemisia vulgaris (1.36 IU/mL), and Artemisia absinthium (0.49 IU/mL) were found. An ImmunoCap ISAC test found an average level of specific IgE against mugwort pollen allergen component Art v 1 - 5,7 ISU-E, indicating an allergy to mugwort pollen and low to medium levels of specific IgE against lipid transfer proteins (LTP) found in walnuts, peanuts, mugwort pollen, and hazelnuts. Through the ISAC inhibition test we proved that sunflower seed allergen extracts contain proteins cross-reactive with patients’ IgE specific to Art v 1, Art v 3, and Jug r 3. Based on our results and the clinical pattern of the disease we confirmed that the patient is allergic to mugwort pollen and that he had an anaphylactic reaction as a result of ingesting sunflower seeds. We suspected that hypersensitivity to sunflower LTP and defensin-like proteins, both cross-reactive with mugwort pollen allergens, were the main cause of the patient’s anaphylactic reaction. PMID:27222528
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Hilhorst, H.W.M.; Finch-Savage, W.E.; Buitink, J.; Bolingue, W.; Leubner-Metzger, G.
2010-01-01
Seed dormancy has been studied intensely over the past decades and, at present, knowledge of this plant trait is at the forefront of plant biology. The main model species is Arabidopsis thaliana, an annual weed, possessing nondeep physiological dormancy. This overview presents the state-of-the-art
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Seed dormancy and germination - Emerging mechanisms and new hypotheses
Directory of Open Access Journals (Sweden)
Hiroyuki eNonogaki
2014-05-01
Full Text Available Seed dormancy has played a significant role in adaptation and evolution of seed plants. While its biological significance is clear, molecular mechanisms underlying seed dormancy induction, maintenance and alleviation still remain elusive. Intensive efforts have been made to investigate gibberellin and abscisic acid metabolism in seeds, which greatly contributed to the current understanding of seed dormancy mechanisms. Other mechanisms, which might be independent of hormones, or specific to the seed dormancy pathway, are also emerging from genetic analysis of seed dormancy mutants. These studies suggest that chromatin remodeling through histone ubiquitination, methylation and acetylation, which could lead to transcription elongation or gene silencing, may play a significant role in seed dormancy regulation. Small interfering RNA and/or long non-coding RNA might be a trigger of epigenetic changes at the seed dormancy or germination loci, such as DELAY OF GERMINATION1. While new mechanisms are emerging from genetic studies of seed dormancy, novel hypotheses are also generated from seed germination study with high throughput gene expression analysis. Recent studies on tissue-specific gene expression in tomato and Arabidopsis seeds, which suggested possible mechanosensing in the regulatory mechanisms, advanced our understanding of embryo-endosperm interaction and have potential to re-draw the traditional hypotheses or integrate them into a comprehensive scheme. The progress in basic seed science will enable knowledge translation, another frontier of research to be expanded for food and fuel production.
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Iron Deficiency Prolongs Seed Dormancy in Arabidopsis Plants
Directory of Open Access Journals (Sweden)
Irene Murgia
2017-12-01
Full Text Available The understanding of seed dormancy, germination and longevity are important goals in plant biology, with relevant applications for agriculture, food industry and also human nutrition. Reactive Oxygen Species (ROS are key molecules involved in the release of dormancy, when their concentrations fall within the so called ‘oxidative window.’ The mechanisms of ROS distribution and sensing in seeds, from dormant to germinating ones, still need elucidation. Also, the impact of iron (Fe deficiency on seed dormancy is still unexplored; this is surprising, given the known pro-oxidant role of Fe when in a free form. We provide evidence of a link between plant Fe nutrition and dormancy of progeny seeds by using different Arabidopsis ecotypes and mutants with different dormancy strengths grown in control soil or under severe Fe deficiency. The latter condition extends the dormancy in several genotypes. The focus on the mechanisms involved in the Fe deficiency-dependent alteration of dormancy and longevity promises to be a key issue in seed (redox biology.
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Directory of Open Access Journals (Sweden)
Denise de Castro Lima
Full Text Available The sunflower is among the top five crops in the world for the production of edible vegetable oil. The species displays rustic behavior, with an excellent edaphic and climatic adaptability index, being able to be cultivated throughout Brazil. Seed quality is the key to increasing production and productivity in the sunflower. The objective of this work was to monitor the viability of sunflower seeds with a view to their conservation when stored in different environments and packaging. The seeds were packed in paper bags, multilayered paper, black polyethylene and PET bottles; and stored for a period of twelve months in the following environments: dry cold room (10 ºC and 55% RH, the ambient conditions of Fortaleza, Ceará, Brazil (30-32 ºC and 75% RH, refrigerator (4 ºC and 38-43% RH and freezer (-20 ºC. Every three months, the water content of the seeds was determined and germination, accelerated ageing, speed of emergence index, and seedling dry weight were evaluated. The experimental design was completely randomized, in a scheme of split-lots, with four replications. It can be concluded that the natural environment is not suitable for the storage of sunflower seeds. Sunflower seeds remain viable for 12 months when stored in a dry cold room, refrigerator or freezer, irrespective of the type of packaging used.
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Dormancy Breaking in Ormosia arborea Seeds
Directory of Open Access Journals (Sweden)
Edilma Pereira Gonçalves
2011-01-01
Full Text Available Ormosia arborea is a tree species planted in urban areas and used to restore degraded areas. Its seeds are dormant and propagation is difficult. This study compares different dormancy breaking methods and physiological seed quality and seedling production. The seeds were germinated in sand in the laboratory of the Universidade Estadual de Santa Cruz, Ilhéus, Bahia, Brazil. The following dormancy breaking treatments were applied: control (intact seeds, 100°C water immersion; boiling water immersion followed by 24 hours of soaking; scarification with number 100 and number 50 sandpaper opposite from root emergence; sulfuric acid immersion for 1 hour, 50, 45, and 30 minutes. Seed immersion in 100°C and boiling water did not break the dormancy. The study species showed a greater vigor of seedling when its seeds were submitted to treatments associated with tegument rupturing by sandpaper or sulfuric acid. On the other hand, seed scarification with sulfuric acid for 1 hour, 50, 45, and 30 minutes or sandpaper favored seed germination and vigor.
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Assessment of Seed Germination and Dormancy of Thirty Seeds Lots of
Directory of Open Access Journals (Sweden)
H.R Ehyaee
2012-06-01
Full Text Available Most seeds of medicinal plants due to ecological adaptation to environmental conditions have several types of dormancy. Hence, it's necessary to recognize ecological factors that affect dormancy and provide optimum conditions for germination in medicinal plant species. Thirty seed lots were used to estimate germination and dormancy of medicinal plants. Treatments were KNO3, (2% and scarification of seeds by sand paper, hypochlorite sodium and removing the seed coat with four replicates of 25 seeds. Maximum and minimum germination observed in H2O for Digitalis purpure 100% and Saponaria officinalis 0%. In KNO3 treatment, Portulaca oleracea had the highest germination of 91% and Hyocyamus niger had no any germinated seeds. In sand paper treatment, the Saponaria officinalis and Datura stramonium had maximum, 33% and minimum 0% germination respectively.
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Orozco-Segovia, A.; Márquez-Guzmán, J.; Sánchez-Coronado, M. E.; Gamboa de Buen, A.; Baskin, J. M.; Baskin, C. C.
2007-01-01
Background and Aims There is considerable confusion in the literature concerning impermeability of seeds with ‘hard’ seed coats, because the ability to take up (imbibe) water has not been tested in most of them. Seeds of Opuntia tomentosa were reported recently to have a water-impermeable seed coat sensu lato (i.e. physical dormancy), in combination with physiological dormancy. However, physical dormancy is not known to occur in Cactaceae. Therefore, the aim of this study was to determine if seeds of O. tomentosa are water-permeable or water-impermeable, i.e. if they have physical dormancy. Methods The micromorphology of the seed coat and associated structures were characterized by SEM and light microscopy. Permeability of the seed-covering layers was assessed by an increase in mass of seeds on a wet substrate and by dye-tracking and uptake of tritiated water by intact versus scarified seeds. Key Results A germination valve and a water channel are formed in the hilum–micropyle region during dehydration and ageing in seeds of O. tomentosa. The funicular envelope undoubtedly plays a role in germination of Opuntia seeds via restriction of water uptake and mechanical resistance to expansion of the embryo. However, seeds do not exhibit any of three features characteristic of those with physical dormancy. Thus, they do not have a water-impermeable layer(s) of palisade cells (macrosclereids) or a water gap sensu stricto and they imbibe water without the seed coat being disrupted. Conclusions Although dormancy in seeds of this species can be broken by scarification, they have physiological dormancy only. Further, based on information in the literature, it is concluded that it is unlikely that any species of Opuntia has physical dormancy. This is the first integrative study of the anatomy, dynamics of water uptake and dormancy in seeds of Cactaceae subfamily Opuntioideae. PMID:17298989
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Regulation of seasonal patterns in seed dormancy
Derkx, M.P.M.
1993-01-01
Buried seeds of many wild species pass annually through a pattern of induction and release of dormancy. These reversible changes in dormancy may be repeated for numbers of years when seeds are deprived from light and other germination-stimulating factors, and are a highly useful adaptation
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Sunflower seeds as eliciting agents of Compositae dermatitis
DEFF Research Database (Denmark)
Paulsen, Evy; El-Houri, Rime B; Andersen, Klaus Ejner
2015-01-01
BACKGROUND: Sunflowers may cause dermatitis because of allergenic sesquiterpene lactones (SLs). Contact sensitization to sunflower seeds has also been reported, but the allergens are unknown. OBJECTIVES: To analyse sunflower seeds for the presence of SLs and to assess the prevalence of sunflower...... sensitization in Compositae-allergic individuals. PATIENTS/MATERIALS/METHODS: Sunflower-sensitive patients were identified by aimed patch testing. A dichloromethane extract of whole sunflower seeds was analysed by liquid chromatography-mass spectrometry and high-performance liquid chromatography. RESULTS......: The prevalence of sensitivity to sunflower in Compositae-allergic individuals was 56%. A solvent wash of whole sunflower seeds yielded an extract containing SLs, the principal component tentatively being identified as argophyllin A or B, other SLs being present in minute amounts. CONCLUSIONS: The concentration...
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Seed storage-mediated dormancy alleviation in Fabaceae from campo rupestre
Directory of Open Access Journals (Sweden)
Naïla Nativel
2015-09-01
Full Text Available ABSTRACTWe studied the effects of seed storage on germination and dormancy alleviation in three species of Fabaceae endemic to campo rupestrein southeastern Brazil. Fresh seeds of Collaea cipoensis, Mimosa maguirei and Mimosa foliolosawere set to germinate and germination of seeds after four, five and 13 years of storage was tested. Seed viability was maintained for all species after the full storage period. Seed storage significantly increased germination percentage and decreased germination time for C. cipoensisand M. foliolosa, suggesting the alleviation of physical dormancy with storage. However, we did not find evidence of dormancy alleviation in M. maguirei since stored seeds showed a decrease in germination in comparison to that of fresh seeds. Our data indicate species-specific storage-mediated dormancy alleviation, which will have important implications for restoration of campo rupestre.
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Effects of different methods of breaking dormancy and seed ...
African Journals Online (AJOL)
Seed dormancy in palms, date palm inclusive have continued to be challenging especially when cultivating through seeds. This study evaluated different methods of breaking dormancy and seed germination rate in P. dactylifera. Using Completely Randomize Design, two varieties of P. dactylifera were treated with three ...
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7 CFR 810.1801 - Definition of sunflower seed.
2010-01-01
... 7 Agriculture 7 2010-01-01 2010-01-01 false Definition of sunflower seed. 810.1801 Section 810... STATES STANDARDS FOR GRAIN United States Standards for Sunflower Seed Terms Defined § 810.1801 Definition of sunflower seed. Grain that, before the removal of foreign material, consists of 50.0 percent or...
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Seed after-ripening and dormancy determine adult life history independently of germination timing.
de Casas, Rafael Rubio; Kovach, Katherine; Dittmar, Emily; Barua, Deepak; Barco, Brenden; Donohue, Kathleen
2012-05-01
• Seed dormancy can affect life history through its effects on germination time. Here, we investigate its influence on life history beyond the timing of germination. • We used the response of Arabidopsis thaliana to chilling at the germination and flowering stages to test the following: how seed dormancy affects germination responses to the environment; whether variation in dormancy affects adult phenology independently of germination time; and whether environmental cues experienced by dormant seeds have an effect on adult life history. • Dormancy conditioned the germination response to low temperatures, such that prolonged periods of chilling induced dormancy in nondormant seeds, but stimulated germination in dormant seeds. The alleviation of dormancy through after-ripening was associated with earlier flowering, independent of germination date. Experimental dormancy manipulations showed that prolonged chilling at the seed stage always induced earlier flowering, regardless of seed dormancy. Surprisingly, this effect of seed chilling on flowering time was observed even when low temperatures did not induce germination. • In summary, seed dormancy influences flowering time and hence life history independent of its effects on germination timing. We conclude that the seed stage has a pronounced effect on life history, the influence of which goes well beyond the timing of germination. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.
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HONSU, a protein phosphatase 2C, regulates seed dormancy by inhibiting ABA signaling in Arabidopsis.
Kim, Woohyun; Lee, Yeon; Park, Jeongmoo; Lee, Nayoung; Choi, Giltsu
2013-04-01
Seed dormancy, a seed status that prohibits germination even in the presence of inductive germination signals, is a poorly understood process. To identify molecular components that regulate seed dormancy, we screened T-DNA insertion lines and identified a mutant designated honsu (hon). HON loss-of-function mutants display deep seed dormancy, whereas HON-overexpressing lines display shallow seed dormancy. HON encodes a seed-specific group A phosphatase 2C (PP2C) and is one of the major negative regulators of seed dormancy among group A PP2Cs. Like other PP2C family members, HON interacts with PYR1/RCAR11 in the presence of ABA. Our analysis indicates that HON inhibits ABA signaling and activates gibberellic acid signaling, and both of these conditions must be satisfied to promote the release of seed dormancy. However, HON mRNA levels are increased in mutants displaying deep seed dormancy or under conditions that deepen seed dormancy, and decreased in mutants displaying shallow seed dormancy or under conditions that promote the release of seed dormancy. Taken together, our results indicate that the expression of HON mRNA is homeostatically regulated by seed dormancy.
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Maternal environment affects the genetic basis of seed dormancy in Arabidopsis thaliana.
Postma, Froukje M; Ågren, Jon
2015-02-01
The genetic basis of seed dormancy, a key life history trait important for adaptive evolution in plant populations, has yet been studied only using seeds produced under controlled conditions in greenhouse environments. However, dormancy is strongly affected by maternal environmental conditions, and interactions between seed genotype and maternal environment have been reported. Consequently, the genetic basis of dormancy of seeds produced under natural field conditions remains unclear. We examined the effect of maternal environment on the genetic architecture of seed dormancy using a recombinant inbred line (RIL) population derived from a cross between two locally adapted populations of Arabidopsis thaliana from Italy and Sweden. We mapped quantitative trait loci (QTL) for dormancy of seeds produced in the greenhouse and at the native field sites of the parental genotypes. The Italian genotype produced seeds with stronger dormancy at fruit maturation than did the Swedish genotype in all three environments, and the maternal field environments induced higher dormancy levels compared to the greenhouse environment in both genotypes. Across the three maternal environments, a total of nine dormancy QTL were detected, three of which were only detected among seeds matured in the field, and six of which showed significant QTL × maternal environment interactions. One QTL had a large effect on dormancy across all three environments and colocalized with the candidate gene DOG1. Our results demonstrate the importance of studying the genetic basis of putatively adaptive traits under relevant conditions. © 2015 John Wiley & Sons Ltd.
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Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.
Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Kubo, Yuta; Nakamura, Masako; Ichimura, Kazuya; Seo, Shigemi; Kanamori, Hiroyuki; Wu, Jianzhong; Ando, Tsuyu; Hensel, Goetz; Sameri, Mohammad; Stein, Nils; Sato, Kazuhiro; Matsumoto, Takashi; Yano, Masahiro; Komatsuda, Takao
2016-03-21
Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat. Copyright © 2016 Elsevier Ltd. All rights reserved.
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genetics and inheritance of seed dormancy inflicted by seed
African Journals Online (AJOL)
Mgina
ABSTRACT. The study was undertaken to investigate the genetic mode of inheritance of dormancy imposed by the hull (seed coat) in rice seeds. Freshly harvested seeds of parents, F1 and F2 populations of a cross between a dormant cultivar Kisegese and non-dormant strain K2004 were used. Germination test of the ...
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Evaluation of different methods to overcome in vitro seed dormancy ...
African Journals Online (AJOL)
SAM
2014-09-03
Sep 3, 2014 ... Seeds from yellow passion fruit (Passiflora edulis Sims) present dormancy imposed by the seed-coat. The present study aimed to evaluate some methods to overcome dormancy of seeds from P. edulis grown under in vitro conditions. The experimental design was completely randomized in factorial scheme ...
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Directory of Open Access Journals (Sweden)
Sven K. Nelson
2017-12-01
Full Text Available Plant embryos can survive years in a desiccated, quiescent state within seeds. In many species, seeds are dormant and unable to germinate at maturity. They acquire the capacity to germinate through a period of dry storage called after-ripening (AR, a biological process that occurs at 5–15% moisture when most metabolic processes cease. Because stored transcripts are among the first proteins translated upon water uptake, they likely impact germination potential. Transcriptome changes associated with the increased seed dormancy of the GA-insensitive sly1-2 mutant, and with dormancy loss through long sly1-2 after-ripening (19 months were characterized in dry seeds. The SLY1 gene was needed for proper down-regulation of translation-associated genes in mature dry seeds, and for AR up-regulation of these genes in germinating seeds. Thus, sly1-2 seed dormancy may result partly from failure to properly regulate protein translation, and partly from observed differences in transcription factor mRNA levels. Two positive regulators of seed dormancy, DELLA GAI (GA-INSENSITIVE and the histone deacetylase HDA6/SIL1 (MODIFIERS OF SILENCING1 were strongly AR-down-regulated. These transcriptional changes appeared to be functionally relevant since loss of GAI function and application of a histone deacetylase inhibitor led to decreased sly1-2 seed dormancy. Thus, after-ripening may increase germination potential over time by reducing dormancy-promoting stored transcript levels. Differences in transcript accumulation with after-ripening correlated to differences in transcript stability, such that stable mRNAs appeared AR-up-regulated, and unstable transcripts AR-down-regulated. Thus, relative transcript levels may change with dry after-ripening partly as a consequence of differences in mRNA turnover.
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On the role of abscisic acid in seed dormancy of red rice.
Gianinetti, Alberto; Vernieri, Paolo
2007-01-01
Abscisic acid (ABA) is commonly assumed to be the primary effector of seed dormancy, but conclusive evidence for this role is lacking. This paper reports on the relationships occurring in red rice between ABA and seed dormancy. Content of free ABA in dry and imbibed caryopses, both dormant and after-ripened, the effects of inhibitors, and the ability of applied ABA to revert dormancy breakage were considered. The results indicate: (i) no direct correlation of ABA content with the dormancy status of the seed, either dry or imbibed; (ii) different sensitivity to ABA of non-dormant seed and seed that was forced to germinate by fluridone; and (iii) an inability of exogenous ABA to reinstate dormancy in fluridone-treated seed, even though applied at a pH which favoured high ABA accumulation. These considerations suggest that ABA is involved in regulating the first steps of germination, but unidentified developmental effectors that are specific to dormancy appear to stimulate ABA synthesis and to enforce the responsiveness to this phytohormone. These primary effectors appear physiologically to modulate dormancy and via ABA they effect the growth of the embryo. Therefore, it is suggested that ABA plays a key role in integrating the dormancy-specific developmental signals with the control of growth.
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Influence of Fungicides Application and Seed Processing on Sunflower Seed Quality
Šimić, Branimir; Svitlica, Brankica; Ćosić, Jasenka; Andrić, Luka; Rozman, Vlatka; Postić, Jelena; Liović, Ivica
2009-01-01
The aim of the research was to determine influence of methods of seed processing and application of fungicides on mass of 1000 seeds, intergrowth energy and seed germination of sunflower hybrids ‘Favorit’ and ‘Apolon’ in 2005 and 2006. Selected untreated seeds of both sunflower hybrids (control) had a minimal mass of 1000 seeds (55-59 g), intergrowth energy (18-37 %) and seed germination (39-52 %). In both years of research maximal seed quality, mass of 1000 seeds (67-69 g), intergrowth energ...
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Methods for overcoming dormancy in Stryphnodendron pulcherrimum seeds
Directory of Open Access Journals (Sweden)
Adriano Gonçalves Pereira
2016-09-01
Full Text Available Seed dormancy is a phenomenon observed in several tropical species. This condition causes low and non-uniform germination. The present study was designed to identify an efficient method of breaking seed dormancy in Stryphnodendron pulcherrimum. Seeds of four mother plants were subjected to the following treatments: immersion in sulfuric acid for 2, 4, 6, 8, 10 and 12 min and scarification on 150-grit sandpaper. Seeds were sown on substrate containing sand and sawdust (1:1. It was evaluate the days to onset seedlings emergence, seedlings emergence (SE, emergence speed index (ESI, germination (G, hard seeds (HS, dead seeds (DS, dormant seeds (DMS, abnormal seedlings (AS and dry mass of aerial part (DMAP and roots (DMR. The experimental design was completely randomized with four replications of 25 seeds for each treatment. Data were subjected to analysis of variance and means compared by Tukey’s test (p < 0.05. Significant differences among treatments were observed for ESI, SE, G, HS, DMAP and DMR. Highest HS was observed in control treatment (85%. Highest G was observed in seeds scarified with sulfuric acid for 10 min (82% and 12 min (74%. These treatments also showed highest ESI, DMAP and DMR, indicating that these scarification treatments were the most efficient in overcoming dormancy.
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Effect of Time and Burial Depth on Breaking Seed dormancy and Germination of Weed Seeds
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marzie mazhari
2016-02-01
Full Text Available Introduction: Weeds limit crop growth, development and yield through competing. Seed bank of weeds in field is one of the sources which can affect weed management and their control methods. Environmental conditions during seed maturation and following dispersal interact to influence the germination phenology of many species. Disturbance plays a key role in the maintenance of habitat for many plant species, particularly referrals, for example, fire ephemerals, desert annuals, and arable weeds. Seed germination and emergence depend on endogenous and exogenous factors. Viable seeds are dormant when all environmental conditions are appropriate for germination but seeds fail to germinate. Thus, dormancy plays an important ecological role in preventing seed germination, being a major contributor to seed persistence of some species in soil. Buried seeds of annual weeds are certainly subjected to different soil moisture conditions during their dormancy release season (winter according to the annual rainfall pattern and burial depth. Shallow buried seeds are exposed to soil moisture fluctuations that could affect their dormancy status. Laboratory studies showed that desiccation and subsequent re-hydration of seeds could stimulate germination and modify seed light requirements. Seeds buried in deeper layers of the soil would not be exposed to such fluctuations in soil moisture, but would be exposed to different soil moisture environments depending on weather and soil characteristics. The effects of interactions between temperature, and soil or seed moisture, on seed dormancy changes have been reported for several species. Therefore, the objectives of this study were to determine the effect of time and burial depth treatments on seed germination and seedling emergence of Aegilops cylindrica, Agropyrom repens, Avena fatua, Bromus dantoniae, Cynodon dactylon, Cyprus rotundus, Setaria viridis, Anthriscus sylvestris, Centurea cyanus. Materials and Methods: In
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Seed dormancy and germination vary within and among species of milkweeds
Kaye, Thomas N; Sandlin, Isaac J; Bahm, Matt A
2018-01-01
Abstract Pollinators in general and monarch butterflies in particular are in decline due to habitat loss. Efforts to restore habitats for insects that rely on specific plant groups as larvae or adults depend on the ability of practitioners to grow and produce these plants. Monarch larvae feed exclusively on milkweed species, primarily in the genus Asclepias, making propagation and restoration of these plants crucial for habitat restoration. Seed germination protocols for milkweeds are not well established, in part due to the large number of milkweed species and conflicting reports of seed dormancy in the genus. We tested for seed dormancy and the optimum period of cold stratification in 15 populations of A. speciosa and 1–2 populations of five additional species, including A. asperula, A. fascicularis, A. subulata, A. subverticillata and A. syriaca. We exposed seeds to cold (5 °C) moist conditions for 0, 2, 4, 6 and 8 weeks and then moved them to 15 °C/25 °C alternating temperatures. In A. speciosa, dormancy was detected in eight populations, and this dormancy was broken by 2–4 weeks of cold stratification. The remaining seven populations showed no dormancy. Seed dormancy was also detected in two populations of A. fascicularis (broken by 4–6 weeks of cold stratification) and a single population of A. syriaca (broken by 2 weeks of cold stratification). No dormancy was detected in A. asperula, A. subulata or A. subverticillata. Seed dormancy appears to be widespread in the genus (confirmed in 15 species) but can vary between populations even within the same species. Variation in seed dormancy and cold stratification requirements within and among Asclepias species suggests local adaptation and maternal environments may drive seedling ecology, and that growers should watch for low germination and use cold stratification as needed to maximize seed germination and retain genetic variability in restored populations. PMID:29593856
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Variation for seed phytosterols in sunflower germplasm
Sunflower (Helianthus annuus L.) seeds and oils are rich sources of phytosterols, which are important compounds for human nutrition. There is limited information on variability for seed phytosterols in sunflower germplasm. The objective of the present research was to evaluate kernel phytosterol cont...
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While widespread transcriptome changes have been previously observed with seed dormancy loss, this study specifically characterized transcriptional changes associated with the increased seed dormancy and dormancy loss of the gibberellin (GA) hormone-insensitive sleepy1-2 (sly1-2) mutant. The SLY1 g...
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Tanned or burned: the role of fire in shaping physical seed dormancy.
Moreira, Bruno; Pausas, Juli G
2012-01-01
Plant species with physical seed dormancy are common in mediterranean fire-prone ecosystems. Because fire breaks seed dormancy and enhances the recruitment of many species, this trait might be considered adaptive in fire-prone environments. However, to what extent the temperature thresholds that break physical seed dormancy have been shaped by fire (i.e., for post-fire recruitment) or by summer temperatures in the bare soil (i.e., for recruitment in fire-independent gaps) remains unknown. Our hypothesis is that the temperature thresholds that break physical seed dormancy have been shaped by fire and thus we predict higher dormancy lost in response to fire than in response to summer temperatures. We tested this hypothesis in six woody species with physical seed dormancy occurring in fire-prone areas across the Mediterranean Basin. Seeds from different populations of each species were subject to heat treatments simulating fire (i.e., a single high temperature peak of 100 °C, 120 °C or 150 °C for 5 minutes) and heat treatments simulating summer (i.e., temperature fluctuations; 30 daily cycles of 3 hours at 31 °C, 4 hours at 43 °C, 3 hours at 33 °C and 14 hours at 18 °C). Fire treatments broke dormancy and stimulated germination in all populations of all species. In contrast, summer treatments had no effect over the seed dormancy for most species and only enhanced the germination in Ulex parviflorus, although less than the fire treatments. Our results suggest that in Mediterranean species with physical dormancy, the temperature thresholds necessary to trigger seed germination are better explained as a response to fire than as a response to summer temperatures. The high level of dormancy release by the heat produced by fire might enforce most recruitment to be capitalized into a single post-fire pulse when the most favorable conditions occur. This supports the important role of fire in shaping seed traits.
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Tanned or burned: the role of fire in shaping physical seed dormancy.
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Bruno Moreira
Full Text Available Plant species with physical seed dormancy are common in mediterranean fire-prone ecosystems. Because fire breaks seed dormancy and enhances the recruitment of many species, this trait might be considered adaptive in fire-prone environments. However, to what extent the temperature thresholds that break physical seed dormancy have been shaped by fire (i.e., for post-fire recruitment or by summer temperatures in the bare soil (i.e., for recruitment in fire-independent gaps remains unknown. Our hypothesis is that the temperature thresholds that break physical seed dormancy have been shaped by fire and thus we predict higher dormancy lost in response to fire than in response to summer temperatures. We tested this hypothesis in six woody species with physical seed dormancy occurring in fire-prone areas across the Mediterranean Basin. Seeds from different populations of each species were subject to heat treatments simulating fire (i.e., a single high temperature peak of 100 °C, 120 °C or 150 °C for 5 minutes and heat treatments simulating summer (i.e., temperature fluctuations; 30 daily cycles of 3 hours at 31 °C, 4 hours at 43 °C, 3 hours at 33 °C and 14 hours at 18 °C. Fire treatments broke dormancy and stimulated germination in all populations of all species. In contrast, summer treatments had no effect over the seed dormancy for most species and only enhanced the germination in Ulex parviflorus, although less than the fire treatments. Our results suggest that in Mediterranean species with physical dormancy, the temperature thresholds necessary to trigger seed germination are better explained as a response to fire than as a response to summer temperatures. The high level of dormancy release by the heat produced by fire might enforce most recruitment to be capitalized into a single post-fire pulse when the most favorable conditions occur. This supports the important role of fire in shaping seed traits.
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Induction of 9-cis-epoxycarotenoid dioxygenase in Arabidopsis thaliana seeds enhances seed dormancy.
Martínez-Andújar, Cristina; Ordiz, M Isabel; Huang, Zhonglian; Nonogaki, Mariko; Beachy, Roger N; Nonogaki, Hiroyuki
2011-10-11
Full understanding of mechanisms that control seed dormancy and germination remains elusive. Whereas it has been proposed that translational control plays a predominant role in germination, other studies suggest the importance of specific gene expression patterns in imbibed seeds. Transgenic plants were developed to permit conditional expression of a gene encoding 9-cis-epoxycarotenoid dioxygenase 6 (NCED6), a rate-limiting enzyme in abscisic acid (ABA) biosynthesis, using the ecdysone receptor-based plant gene switch system and the ligand methoxyfenozide. Induction of NCED6 during imbibition increased ABA levels more than 20-fold and was sufficient to prevent seed germination. Germination suppression was prevented by fluridone, an inhibitor of ABA biosynthesis. In another study, induction of the NCED6 gene in transgenic seeds of nondormant mutants tt3 and tt4 reestablished seed dormancy. Furthermore, inducing expression of NCED6 during seed development suppressed vivipary, precocious germination of developing seeds. These results indicate that expression of a hormone metabolism gene in seeds can be a sole determinant of dormancy. This study opens the possibility of developing a robust technology to suppress or promote seed germination through engineering pathways of hormone metabolism.
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Inheritance of fresh seed dormancy in groundnut
African Journals Online (AJOL)
SERVER
2008-02-19
Feb 19, 2008 ... Seed dormancy has been defined as the failure of an intact, viable seed to ... expected ratio of 3 dormant : 1 non-dormant seeds in F2 generations of crosses of ICGV 87378 and ICGV ... ICGV 87378 x ICGV 86158. 163. 0. 163.
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New sunflower seeds with high contents of phytosterols
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Velasco Leonardo
2014-11-01
Full Text Available Dietary phytosterols have a positive nutritional impact because they contribute to reduce cholesterol levels in blood. Accordingly, foods rich in phytosterols are required in a healthy diet. Vegetable oils are the richest source of phytosterols in the diet, though sunflower oil has lower phytosterol content than other seed oils such as rapeseed and corn. Increasing phytosterol content in sunflower oil requires optimizing first selection procedures. In this way, the development of accurate methods for analyzing phytosterol content in seeds instead of oils has opened up recently the way for large-scale screening for this trait. Large variability for seed phytosterol content has been identified in sunflower germplasm, from which we have developed a line, IASP-18, with about twofold seed phytosterol content than conventional sunflower. The trait is expressed across environments. Genetic studies are underway to characterize its inheritance and assess the feasibility of introgressing genes for high phytosterol content into elite sunflower germplasm.
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Goggin, Danica E; Emery, R J Neil; Powles, Stephen B; Steadman, Kathryn J
2010-10-15
The physiological and biochemical bases of seed dormancy in Lolium rigidum (annual ryegrass) are largely unknown, and study of this process is complicated by the outcrossing nature of the species and the strong influence of environment on seed dormancy. In order to identify heritable biochemical factors contributing to seed dormancy in L. rigidum, seeds from a field-collected population were used to select sub-populations with consistently low or high seed dormancy over four generations. Low-dormancy seeds showed constitutive alpha-amylase activity prior to imbibition, higher concentrations of polyphenols and cis-zeatin, and lower abscisic acid and cis-zeatin riboside concentrations than high-dormancy seeds. Selection for high dormancy was associated with a reduction in response to dark-stratification for 21d at 20 degrees C (an effective means of releasing dormancy in the original, unselected population) over successive generations, but fluridone remained effective in breaking dormancy. Crossing of low- and high-dormancy populations indicated that dormancy level was not dependent upon the maternal genotype of the seed, and that the constitutive alpha-amylase activity and high seed anthocyanin concentrations characteristic of the low-dormancy populations were not correlated to high basal germination ability. Copyright (c) 2010 Elsevier GmbH. All rights reserved.
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Seasonal pattern of seed dormancy in parthenium hysterophorus L
International Nuclear Information System (INIS)
Arshad Javaid, A.; Shafique, S.; Shafique, S.
2010-01-01
Earlier non-conclusive results have been reported on the initial dormancy status of parthenium (Parthenium hysterophorus L.) seeds. The present study reports the seasonal dormancy pattern of parthenium in Lahore, Pakistan where there are four distinct seasons viz. summer, autumn, winter and spring in a year. Mature parthenium seeds were collected on the last day of each month from January to December 2006 and investigations for their germination percentage and rate of germination were started on the next day. Parthenium seeds collected during coldest months of January and December showed highest germination of 100% with germination rate of 33.3% per day. Conversely, seeds collected in summer months of April to September exhibited lowest germination of 0-7% and germination rate of 0-1.75% per day. Seeds collected in rest of the months showed variable final germination percentage and germination rate ranging from 30-97% and 3.8-17.4%, respectively. Both the final germination and germination rate showed a highly significant negative correlation with the solar radiation and environmental temperature during the seed development period. The present study concludes that dormancy in parthenium seeds depends upon the temperature and solar radiation during the seed development period. (author)
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The Arabidopsis MYB96 transcription factor plays a role in seed dormancy.
Lee, Hong Gil; Lee, Kyounghee; Seo, Pil Joon
2015-03-01
Seed dormancy facilitates to endure environmental disadvantages by confining embryonic growth until the seeds encounter favorable environmental conditions for germination. Abscisic acid (ABA) and gibberellic acid (GA) play a pivotal role in the determination of the seed dormancy state. ABA establishes seed dormancy, while GA triggers seed germination. Here, we demonstrate that MYB96 contributes to the fine-tuning of seed dormancy regulation through the coordination of ABA and GA metabolism. The MYB96-deficient myb96-1 seeds germinated earlier than wild-type seeds, whereas delayed germination was observed in the activation-tagging myb96-1D seeds. The differences in germination rate disappeared after stratification or after-ripening. The MYB96 transcription factor positively regulates ABA biosynthesis genes 9-CIS-EPOXYCAROTENOID DIOXYGENASE 2 (NCED2), NCED5, NCED6, and NCED9, and also affects GA biosynthetic genes GA3ox1 and GA20ox1. Notably, MYB96 directly binds to the promoters of NCED2 and NCED6, primarily modulating ABA biosynthesis, which subsequently influences GA metabolism. In agreement with this, hyperdormancy of myb96-1D seeds was recovered by an ABA biosynthesis inhibitor fluridone, while hypodormancy of myb96-1 seeds was suppressed by a GA biosynthesis inhibitor paclobutrazol (PAC). Taken together, the metabolic balance of ABA and GA underlies MYB96 control of primary seed dormancy.
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Directory of Open Access Journals (Sweden)
M. R. Labbafi
2018-03-01
Full Text Available Seed dormancy is a common phase of the plant life cycle; different treatments can be used for breaking dormancy. The aim of this study was to find the best treatment for breaking dormancy and improve germination of caper (Capparis spinosa L.. This study based on the completely randomized design (CRD with 3 replications was done at research Laboratory of Medicinal Plants Institute, ACECR, Karaj, Iran. After different induction treatments containing different levels of potassium nitrate (KNO3, GA3, soaking and soaking with runner water, sulfuric acid, thidiazuron, and benzyl amino-purine, seeds were placed in Petri-dishes and incubated in two temperature regimes, first at fixed 20 ͦC, and second, alternate between 20 and 30 ͦC. The result showed that the germination percentage and germination rate of caper increased up to 75% and 1.35 respectively when the seeds treated with sulfuric acid for 15 min, and 2000 ppm GA3 under alternate 20-30 ͦC temperatures. Caper seed dormancy is mainly due to the inhibitors and hard seed coat that it prevents seed germination.
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Van Klinken, Rieks D; Lukitsch, Bert; Cook, Carly
2008-08-01
Parkinsonia aculeata (Caesalpinaceae) is a perennial legume with seeds that have hard-seeded (physical) dormancy and are potentially very long-lived. Seed dormancy is a characteristic that can both help maximize the probability of seedling establishment and spread the risk of recruitment failure across years (bet-hedging). In this study, dormancy-release patterns are described across the diverse environments in which this species occurs in order to test whether wet heat (incubation under wet, warm-to-hot, conditions) alone can explain those patterns, and in order to determine the likely ecological role of physical dormancy across this species distribution. A seed burial trial was conducted across the full environmental distribution of P. aculeata in Australia (arid to wet-dry tropics, uplands to wetlands, soil surface to 10 cm deep). Wet heat explained the pattern of dormancy release across all environments. Most seeds stored in the laboratory remained dormant throughout the trial (at least 84 %). Dormancy release was quickest for seeds buried during the wet season at relatively high rainfall, upland sites (only 3 % of seeds remained dormant after 35 d). The longest-lived seeds were in wetlands (9 % remained dormant after almost 4 years) and on the soil surface (57 % after 2 years). There was no consistent correlation between increased aridity and rate of dormancy release. The results suggest that physical dormancy in P. aculeata is a mechanism for maximizing seedling establishment rather than a bet-hedging strategy. However, seed persistence can occur in environmental refuges where dormancy-release cues are weak and conditions for germination and establishment are poor (e.g. under dense vegetation or in more arid micro-environments) or unsuitable (e.g. when seeds are inundated or on the soil surface). Risks of recruitment failure in suboptimal environments could therefore be reduced by inter-year fluctuations in microclimate or seed movement.
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Maturation, temperature and breaking dormancy of Comanthera seeds
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Andréa Santos Oliveira
2016-09-01
Full Text Available Given the importance of “everlasting” plants for their ornamental value and vulnerability to extractive practices, studies to ensure the propagation of the species are indispensable. The aim of this study was to assess whether there is an association between seed coat color and the quality of everlasting seeds, in the presence or absence of dormancy. Four species (Comanthera elegans, C. nitida, C. bisculata, and Comanthera sp. were separated with respect to seed coat color and underwent germination first count, germination, and germination speed index testing in a substrate moistened with water or 0.1% fluridone solution, in alternating temperatures of 10/25°C and 15/25°C. A completely randomized experimental design was used in a 4 x 2 x 2 factorial arrangement [seed coat color (green, beige, red, brown × temperature (10/25°C and 15/25°C × dormancy breaking (with or without]. In general, the alternating 15/25°C temperature is favorable for germination of everlasting plants. The use of fluridone is favorable to germination and seed vigor, especially when using the alternating temperature of 10/25°C. The effect of seed coat color varies among species; higher germination and vigor values are seen in green seeds for Comanthera sp. and lower values in C. bisculata. For C. nitida and C. elegans, seed coat color does not influence seed quality. Direct relationships between fluoridone efficiency in breaking dormancy of seeds of different species of everlasting plants and classification in different colors are not observed.
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FEATURES OF THE SEED DORMANCY IN UMBELLIFER CROPS CAUSED BY VARIOUS FACTORS
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D. N. Baleev
2017-01-01
Full Text Available Experiments were carried out at FGBNU VNIIO in 20112016. The aim of the study was to analyze the influence of different types of organic dormancy caused by various factors on seed quality of some representatives of umbellifer crops. The objects of the study were seeds: parsnip ‘Kulinar’ (Pastinaca sativa L.; carrot ‘Rogneda’ (Daucus carrota L.; root parsley ‘Ljubasha’ (Petroselinum crispum (Mill. Nyman ex A.W. Hill.; root celery ‘Kupidon’ (Apium graveolens L.; coriander ‘Yantar’ (Coriandrum sativum L. and dill ‘Kentavr’ (Anethum graveolens L.. In all seeds studied, the speed of embryo growth was decreased by 30% or0.03 mma day. Under influence of the induced dormancy caused by incubation in extract from dill seeds, the speed of embryo growth in all species was decreased by 94-97% on average. The process of germination of just picked seeds in all crops studied showed itself in reduction of germinated seed number by 54% as compared with control variant. Under the effect of incubation at high temperature the seeds of parsnip and root celery didn’t germinate, whereas the germination in the seeds of coriander, root parsley and carrot was decreased by 51%, 47% and 46%, respectively as compared with control. There is no germination observed in parsnip, carrot, root celery and coriander under influence of induced dormancy caused by incubation in extract from dill seeds. In this case, the germination of seeds of root parsley and dill was 8.1% and 15%, respectively. The Pearson correlation between the speed of embryo growth and percent of seed germination showed the significant and positive relationship in the range 0.706-0.952. Analysis of variance (ANOVA showed that induced by temperature or allelopathic dormancy had impact on the speed of embryo’s growth in the crops studied, where factor effect was 89-86% depending on type of dormancy. Analysis of variance between the factors of dormancy and germination revealed that all
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ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination
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Erwann eArc
2013-03-01
Full Text Available Dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. It has been clearly demonstrated that dormancy is induced by abscisic acid (ABA during seed development on the mother plant. After seed dispersal, germination is preceded by a decline in ABA in imbibed seeds, which results from ABA catabolism through 8’-hydroxylation. The hormonal balance between ABA and gibberellins (GAs has been shown to act as an integrator of environmental cues to maintain dormancy or activate germination. The interplay of ABA with other endogenous signals is however less documented. In numerous species, ethylene counteracts ABA signaling pathways and induces germination. In Brassicaceae seeds, ethylene prevents the inhibitory effects of ABA on endosperm cap weakening, thereby facilitating endosperm rupture and radicle emergence. Moreover, enhanced seed dormancy in Arabidopsis ethylene-insensitive mutants results from greater ABA sensitivity. Conversely, ABA limits ethylene action by down-regulating its biosynthesis. Nitric oxide (NO has been proposed as a common actor in the ABA and ethylene crosstalk in seed. Indeed, convergent evidence indicates that NO is produced rapidly after seed imbibition and promotes germination by inducing the expression of the ABA 8’-hydroxylase gene, CYP707A2, and stimulating ethylene production. The role of NO and other nitrogen-containing compounds, such as nitrate, in seed dormancy breakage and germination stimulation has been reported in several species. This review will describe our current knowledge of ABA crosstalk with ethylene and NO, both volatile compounds that have been shown to counteract ABA action in seeds and to improve dormancy release and germination.
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Natural variation for seed longevity and seed dormancy are negatively correlated in Arabidopsis
Nguyen, T.P.; Keizer, L.C.P.; Eeuwijk, van F.; Smeekens, S.C.M.; Bentsink, L.
2012-01-01
Dormancy is a state of metabolic arrest that facilitates the survival of organisms during environmental conditions incompatible with their regular course of life. Many organisms have deep dormant stages to promote an extended life span (increased longevity). In contrast, plants have seed dormancy
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7 CFR 810.1804 - Grades and grade requirements for sunflower seed.
2010-01-01
... 7 Agriculture 7 2010-01-01 2010-01-01 false Grades and grade requirements for sunflower seed. 810... AGRICULTURE OFFICIAL UNITED STATES STANDARDS FOR GRAIN United States Standards for Sunflower Seed Principles Governing the Application of Standards § 810.1804 Grades and grade requirements for sunflower seed. Grade...
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A simulation model for seasonal changes in dormancy and germination of weed seeds
Vleeshouwers, L.M.; Bouwmeester, H.J.
2001-01-01
A model has been developed to simulate the annual dormancy cycle of seeds of light-requiring species in the seed bank and the germination of exhumed seeds after irradiation. Simulation of dormancy and germination is based on a physiological model concerning the action of phytochrome in the seed.
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Rubio de Casas, Rafael; Willis, Charles G; Pearse, William D; Baskin, Carol C; Baskin, Jerry M; Cavender-Bares, Jeannine
2017-06-01
Seed dormancy is expected to provide ecological advantages by adjusting germination to the favorable growth period. However, many species produce nondormant seeds, particularly in wet tropical forests, a biogeographic pattern that is not well accounted for in current models. We hypothesized that the global distribution of dormant seeds derives from their adaptive value in predictably fluctuating (i.e. seasonal) environments. However, the advantage conferred by dormancy might ultimately depend on other seed attributes, particularly size. This general model was tested within a phylogenetically informed framework using a data set comprising > 216 000 world-wide observations of Fabaceae, spanning three orders of magnitude in seed size and including both dormant and nondormant seeds. Our results confirmed our hypothesis: nondormant seeds can only evolve in climates with long growing seasons and/or in lineages that produce larger seeds. Conversely, dormancy should be evolutionarily stable in temperate lineages with small seeds. When the favorable season is fleeting, seed dormancy is the only adaptive strategy. Based on these results, we predict that, within a given lineage, taxa producing larger, nondormant seeds will necessarily predominate in aseasonal environments, while plants bearing small, dormant seeds will be dominant under short growing seasons. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
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A tripartite approach identifies the major sunflower seed albumins.
Jayasena, Achala S; Franke, Bastian; Rosengren, Johan; Mylne, Joshua S
2016-03-01
We have used a combination of genomic, transcriptomic, and proteomic approaches to identify the napin-type albumin genes in sunflower and define their contributions to the seed albumin pool. Seed protein content is determined by the expression of what are typically large gene families. A major class of seed storage proteins is the napin-type, water soluble albumins. In this work we provide a comprehensive analysis of the napin-type albumin content of the common sunflower (Helianthus annuus) by analyzing a draft genome, a transcriptome and performing a proteomic analysis of the seed albumin fraction. We show that although sunflower contains at least 26 genes for napin-type albumins, only 15 of these are present at the mRNA level. We found protein evidence for 11 of these but the albumin content of mature seeds is dominated by the encoded products of just three genes. So despite high genetic redundancy for albumins, only a small sub-set of this gene family contributes to total seed albumin content. The three genes identified as producing the majority of sunflower seed albumin are potential future candidates for manipulation through genetics and breeding.
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Ethylene, a key factor in the regulation of seed dormancy
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Françoise eCORBINEAU
2014-10-01
Full Text Available Ethylene is an important component of the gaseous environment, and regulates numerous plant developmental processes including seed germination and seedling establishment. Dormancy, the inability to germinate in apparently favorable conditions, has been demonstrated to be regulated by the hormonal balance between abscisic acid (ABA and gibberellins (GAs. Ethylene plays a key role in dormancy release in numerous species, the effective concentrations allowing the germination of dormant seeds ranging between 0.1 and 200 μL L-1. Studies using inhibitors of ethylene biosynthesis or of ethylene action and analysis of mutant lines altered in genes involved in the ethylene signaling pathway (etr1, ein2, ain1, etr1, and erf1 demonstrate the involvement of ethylene in the regulation of germination and dormancy. Ethylene counteracts ABA effects through a regulation of ABA metabolism and signaling pathways. Moreover, ethylene insensitive mutants in Arabidopsis are more sensitive to ABA and the seeds are more dormant. Numerous data also show an interaction between ABA, GAs and ethylene metabolism and signaling pathways. It has been increasingly demonstrated that reactive oxygen species (ROS may play a significant role in the regulation of seed germination interacting with hormonal signaling pathways. In the present review the responsiveness of seeds to ethylene will be described, and the key role of ethylene in the regulation of seed dormancy via a cross-talk between hormones and other signals will be discussed.
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Energy Technology Data Exchange (ETDEWEB)
Kitchen, S.G.; Meyer, S.E. (Dept of Agriculture, Provo, UT (United States))
1992-03-01
Penstemon palmeri is a short-lived perennial herb colonizing disturbed sites in semiarid habitats in the western US. In this study seed was harvested from six native and four seeded populations during two consecutive years. In laboratory germination trials at constant 15C, considerable between-lot variation in primary dormancy and light requirement was observed. Four weeks of moist chilling (1C) induced secondary dormancy at 15C. Cold-induced secondary dormancy was reversed by one week of dark incubation at 30C. This warm incubation treatment also reduced the light requirement of unchilled, after-ripened seed. Fluctuations in dormancy and light requirement of buried seeds have been linked to seasonal changes in soil temperature. Penstemon palmeri germination responses to temperature appear to be similar to those of facultative winter annuals.
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Directory of Open Access Journals (Sweden)
Pham A. Tuan
2018-05-01
Full Text Available Seed dormancy is an adaptive trait that does not allow the germination of an intact viable seed under favorable environmental conditions. Non-dormant seeds or seeds with low level of dormancy can germinate readily under optimal environmental conditions, and such a trait leads to preharvest sprouting, germination of seeds on the mother plant prior to harvest, which significantly reduces the yield and quality of cereal crops. High level of dormancy, on the other hand, may lead to non-uniform germination and seedling establishment. Therefore, intermediate dormancy is considered to be a desirable trait as it prevents the problems of sprouting and allows uniformity of postharvest germination of seeds. Induction, maintenance, and release of seed dormancy are complex physiological processes that are influenced by a wide range of endogenous and environmental factors. Plant hormones, mainly abscisic acid (ABA and gibberellin (GA, are the major endogenous factors that act antagonistically in the control of seed dormancy and germination; ABA positively regulates the induction and maintenance of dormancy, while GA enhances germination. Significant progress has been made in recent years in the elucidation of molecular mechanisms regulating ABA/GA balance and thereby dormancy and germination in cereal seeds, and this review summarizes the current state of knowledge on the topic.
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Tuan, Pham A.; Kumar, Rohit; Rehal, Pawanpuneet K.; Toora, Parneet K.; Ayele, Belay T.
2018-01-01
Seed dormancy is an adaptive trait that does not allow the germination of an intact viable seed under favorable environmental conditions. Non-dormant seeds or seeds with low level of dormancy can germinate readily under optimal environmental conditions, and such a trait leads to preharvest sprouting, germination of seeds on the mother plant prior to harvest, which significantly reduces the yield and quality of cereal crops. High level of dormancy, on the other hand, may lead to non-uniform germination and seedling establishment. Therefore, intermediate dormancy is considered to be a desirable trait as it prevents the problems of sprouting and allows uniformity of postharvest germination of seeds. Induction, maintenance, and release of seed dormancy are complex physiological processes that are influenced by a wide range of endogenous and environmental factors. Plant hormones, mainly abscisic acid (ABA) and gibberellin (GA), are the major endogenous factors that act antagonistically in the control of seed dormancy and germination; ABA positively regulates the induction and maintenance of dormancy, while GA enhances germination. Significant progress has been made in recent years in the elucidation of molecular mechanisms regulating ABA/GA balance and thereby dormancy and germination in cereal seeds, and this review summarizes the current state of knowledge on the topic. PMID:29875780
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Effect of storage in overcoming seed dormancy of Annona coriacea Mart. seeds
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DAIANE M. DRESCH
2014-12-01
Full Text Available The aim of this study was to evaluate the effect of pre-treatments on overcoming dormancy of A. coriacea seeds. Seeds were processed and stored in polyethylene bags at temperatures of at -18°C (42% RH, 5°C (34% RH, 15°C (60% RH and 25°C (34% RH, during 0, 30, 60, 90, 120 and 150 days. After storage, seeds were immersed in 350 mg.L−1 gibberellic acid for 144 hours. Sowing was carried out in plastic bags containing Red Latosol + Bioplant®. Moisture content, emergence percentage, emergence speed index, length and dry mass of seedlings, were evaluated. The experimental design was completely randomized in a factorial with four replications of 50 seeds each. The seed storage at 5°C and subsequent immersion in gibberellic acid was efficient to reach high percentage, emergence speed and plant growth. A. coriacea seeds showed non-deep simple morphophysiological dormancy wherein the physiological component can be overcome after the seeds are storage at 5°C for a maximum period of 53 days and subsequent immersed in exogenous GA (350 mg.L−1 for 144 hours.
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Effect of storage in overcoming seed dormancy of Annona coriacea Mart. seeds.
Dresch, Daiane M; Scalon, Silvana P Q; Masetto, Tathiana E
2014-12-01
The aim of this study was to evaluate the effect of pre-treatments on overcoming dormancy of A. coriacea seeds. Seeds were processed and stored in polyethylene bags at temperatures of at -18°C (42% RH), 5°C (34% RH), 15°C (60% RH) and 25°C (34% RH), during 0, 30, 60, 90, 120 and 150 days. After storage, seeds were immersed in 350 mg.L-1 gibberellic acid for 144 hours. Sowing was carried out in plastic bags containing Red Latosol + Bioplant®. Moisture content, emergence percentage, emergence speed index, length and dry mass of seedlings, were evaluated. The experimental design was completely randomized in a factorial with four replications of 50 seeds each. The seed storage at 5°C and subsequent immersion in gibberellic acid was efficient to reach high percentage, emergence speed and plant growth. A. coriacea seeds showed non-deep simple morphophysiological dormancy wherein the physiological component can be overcome after the seeds are storage at 5°C for a maximum period of 53 days and subsequent immersed in exogenous GA (350 mg.L-1 for 144 hours).
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[Reason for dormancy of Cuscuta chinensis seed and solving method].
Wang, Xuemin; He, Jiaqing; Cai, Jing; Dong, Zhenguo
2010-02-01
To study the reason for the deep dormancy of the aged Cuscuta chinensis seed and find the solving method. The separated and combined treatments were applied in the orthogonal designed experiments. The aged seed had well water-absorbency; the water and ethanol extracts of the seeds showed an inhibition effect on germination capacity of the seeds. The main reason for the deep dormancy of aged C. chinensis seed is the inhibitors existed in seed. There are two methods to solve the problem. The seeds is immersed in 98% of H2SO4 for 2 min followed by 500 mg x L(-1) of GA3 treatment for 60 min, or in 100 mg x L(-1) of NaOH for 20 min followed by 500 mg x L(-1) of GA3 treatment for 120 min.
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Analysis of natural allelic variation at seed dormancy loci of Arabidopsis thaliana
Alonso-Blanco, C.; Bentsink, L.; Hanhart, C.J.; Vries, de M.H.C.; Koornneef, M.
2003-01-01
Arabidopsis accessions differ largely in their seed dormancy behavior. To understand the genetic basis of this intraspecific variation we analyzed two accessions: the laboratory strain Landsberg erecta (Ler) with low dormancy and the strong-dormancy accession Cape Verde Islands (Cvi). We used a
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Harrison, P.G.
1991-01-01
Mechanisms of dormancy of seeds from an annual population of the seagrass Zostera marina L. (eelgrass) in the SW Netherlands were investigated in the laboratory. Both physiological dormancy (a requirement for reduced salinity for germination) and physical dormancy (imposed by the seed coat) existed
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Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S; Cao, Zhuanqin; Beighley, Donn H; Yang, Jianchang; Gu, Xing-You
2015-11-01
Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. © 2015 American Society of Plant Biologists. All Rights Reserved.
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Yamasaki, Yuji; Gao, Feng; Jordan, Mark C; Ayele, Belay T
2017-09-16
Maturation forms one of the critical seed developmental phases and it is characterized mainly by programmed cell death, dormancy and desiccation, however, the transcriptional programs and regulatory networks underlying acquisition of dormancy and deposition of storage reserves during the maturation phase of seed development are poorly understood in wheat. The present study performed comparative spatiotemporal transcriptomic analysis of seed maturation in two wheat genotypes with contrasting seed weight/size and dormancy phenotype. The embryo and endosperm tissues of maturing seeds appeared to exhibit genotype-specific temporal shifts in gene expression profile that might contribute to the seed phenotypic variations. Functional annotations of gene clusters suggest that the two tissues exhibit distinct but genotypically overlapping molecular functions. Motif enrichment predicts genotypically distinct abscisic acid (ABA) and gibberellin (GA) regulated transcriptional networks contribute to the contrasting seed weight/size and dormancy phenotypes between the two genotypes. While other ABA responsive element (ABRE) motifs are enriched in both genotypes, the prevalence of G-box-like motif specifically in tissues of the dormant genotype suggests distinct ABA mediated transcriptional mechanisms control the establishment of dormancy during seed maturation. In agreement with this, the bZIP transcription factors that co-express with ABRE enriched embryonic genes differ with genotype. The enrichment of SITEIIATCYTC motif specifically in embryo clusters of maturing seeds irrespective of genotype predicts a tissue specific role for the respective TCP transcription factors with no or minimal contribution to the variations in seed dormancy. The results of this study advance our understanding of the seed maturation associated molecular mechanisms underlying variation in dormancy and weight/size in wheat seeds, which is a critical step towards the designing of molecular strategies
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Directory of Open Access Journals (Sweden)
Xiao Wen Hu
Full Text Available Studying seed dormancy and its consequent effect can provide important information for vegetation restoration and management. The present study investigated seed dormancy, seedling emergence and seed survival in the soil seed bank of Stipa bungeana, a grass species used in restoration of degraded land on the Loess Plateau in northwest China. Dormancy of fresh seeds was determined by incubation of seeds over a range of temperatures in both light and dark. Seed germination was evaluated after mechanical removal of palea and lemma (hulls, chemical scarification and dry storage. Fresh and one-year-stored seeds were sown in the field, and seedling emergence was monitored weekly for 8 weeks. Furthermore, seeds were buried at different soil depths, and then retrieved every 1 or 2 months to determine seed dormancy and seed viability in the laboratory. Fresh seeds (caryopses enclosed by palea and lemma had non-deep physiological dormancy. Removal of palea and lemma, chemical scarification, dry storage (afterripening, gibberellin (GA3 and potassium nitrate (KNO3 significantly improved germination. Dormancy was completely released by removal of the hulls, but seeds on which hulls were put back to their original position germinated to only 46%. Pretreatment of seeds with a 30% NaOH solution for 60 min increased germination from 25% to 82%. Speed of seedling emergence from fresh seeds was significantly lower than that of seeds stored for 1 year. However, final percentage of seedling emergence did not differ significantly for seeds sown at depths of 0 and 1 cm. Most fresh seeds of S. bungeana buried in the field in early July either had germinated or lost viability by September. All seeds buried at a depth of 5 cm had lost viability after 5 months, whereas 12% and 4% seeds of those sown on the soil surface were viable after 5 and 12 months, respectively.
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Evolution with a seed bank: The population genetic consequences of microbial dormancy.
Shoemaker, William R; Lennon, Jay T
2018-01-01
Dormancy is a bet-hedging strategy that allows organisms to persist through conditions that are suboptimal for growth and reproduction by entering a reversible state of reduced metabolic activity. Dormancy allows a population to maintain a reservoir of genetic and phenotypic diversity (i.e., a seed bank) that can contribute to the long-term survival of a population. This strategy can be potentially adaptive and has long been of interest to ecologists and evolutionary biologists. However, comparatively little is known about how dormancy influences the fundamental evolutionary forces of genetic drift, mutation, selection, recombination, and gene flow. Here, we investigate how seed banks affect the processes underpinning evolution by reviewing existing theory, implementing novel simulations, and determining how and when dormancy can influence evolution as a population genetic process. We extend our analysis to examine how seed banks can alter macroevolutionary processes, including rates of speciation and extinction. Through the lens of population genetic theory, we can understand the extent that seed banks influence the evolutionary dynamics of microorganisms as well as other taxa.
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Fresh and matured lamb meat quality fed with sunflower seeds and vitamin E
Sales,Ronaldo Oliveira; Silva Sobrinho,Américo Garcia da; Zeola,Nivea Maria Brancacci Lopes; Lima,Natália Ludmila Lins; Manzi,Gabriela Milani; Almeida,Fabiana Alves de; Endo,Viviane
2013-01-01
The objective of the study is to evaluate meat quality from Ile de France lamb fed diets supplemented with sunflower seeds and vitamin E. Thirty-two lamb weighing initially 15kg were housed in individual stalls and slaughtered when body weight reached 32kg. The treatments consisted of four experimental diets: D1) sugarcane + concentrate without sunflower seeds; D2) sugarcane + concentrate with sunflower seeds; D3) sugarcane + concentrate without sunflower seeds plus 1000mg vitamin E kg-1 diet...
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Comparison of two culture media for breaking seed dormancy and ...
African Journals Online (AJOL)
... the percentage germination and days to germination in each of the four species were higher and faster in water with agar medium in comparison to MS growth medium. These results suggest that the Linum seeds have exogenous and endogenous dormancy. Key words: Dormancy, germination, MS media, Linum species, ...
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Layat, Elodie; Leymarie, Juliette; El-Maarouf-Bouteau, Hayat; Caius, José; Langlade, Nicolas; Bailly, Christophe
2014-12-01
Seed dormancy, which blocks germination in apparently favourable conditions, is a key regulatory control point of plant population establishment. As germination requires de novo translation, its regulation by dormancy is likely to be related to the association of individual transcripts to polysomes. Here, the polysome-associated mRNAs, that is, the translatome, were fractionated and characterized with microarrays in dormant and nondormant sunflower (Helianthus annuus) embryos during their imbibition at 10°C, a temperature preventing germination of dormant embryos. Profiling of mRNAs in polysomal complexes revealed that the translatome differs between germinating and nongerminating embryos. Association of transcripts with polysomes reached a maximum after 15 h of imbibition; at this time-point 194 polysome-associated transcripts were specifically found in nondormant embryos and 47 in dormant embryos only. The proteins corresponding to the polysomal mRNAs in nondormant embryos appeared to be very pertinent for germination and were involved mainly in transport, regulation of transcription or cell wall modifications. This work demonstrates that seed germination results from a timely regulated and selective recruitment of mRNAs to polysomes, thus opening novel fields of investigation for the understanding of this developmental process. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.
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Plant response to sunflower seeds to osmotic conditioning
Directory of Open Access Journals (Sweden)
Camila Santos Barros de Morais
2014-10-01
Full Text Available The aim of this study was to evaluate the effect of seeds osmotic conditioning in seedlings emergence and plants performance of sunflower. Three lots of seeds sunflower (Catissol, was submited to osmotic conditioning with polyethylene glycol solution, –2,0 MPa in aerated system, under 15 ºC for 8 hour and then was evaluated for germination tests and vigour. Under filed conditions was conducted emergency evaluations of seedling, plants development as well as the productivity and seeds quality, and the accumulation of nutrients in the seeds. The osmotic conditioning improve the survival of seedling, the dry matter mass to aerial part of plants from 60 days after sowing and oil content, in lots with low seeds physiological quality. The osmotic conditioning not increase the seeds yield but promotes the vigour of seeds produced, regardless of the lot used for sowing seeds.
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Ye, Heng; Feng, Jiuhuan; Zhang, Lihua; Zhang, Jinfeng; Mispan, Muhamad S.; Cao, Zhuanqin; Beighley, Donn H.; Yang, Jianchang; Gu, Xing-You
2015-01-01
Natural variation in seed dormancy is controlled by multiple genes mapped as quantitative trait loci in major crop or model plants. This research aimed to clone and characterize the Seed Dormancy1-2 (qSD1-2) locus associated with endosperm-imposed dormancy and plant height in rice (Oryza sativa). qSD1-2 was delimited to a 20-kb region, which contains OsGA20ox2 and had an additive effect on germination. Naturally occurring or induced loss-of-function mutations of the gibberellin (GA) synthesis gene enhanced seed dormancy and also reduced plant height. Expression of this gene in seeds (including endospermic cells) during early development increased GA accumulation to promote tissue morphogenesis and maturation programs. The mutant allele prevalent in semidwarf cultivars reduced the seed GA content by up to 2-fold at the early stage, which decelerated tissue morphogenesis including endosperm cell differentiation, delayed abscisic acid accumulation by a shift in the temporal distribution pattern, and postponed dehydration, physiological maturity, and germinability development. As the endosperm of developing seeds dominates the moisture equilibrium and desiccation status of the embryo in cereal crops, qSD1-2 is proposed to control primary dormancy by a GA-regulated dehydration mechanism. Allelic distribution of OsGA20ox2, the rice Green Revolution gene, was associated with the indica and japonica subspeciation. However, this research provided no evidence that the primitive indica- and common japonica-specific alleles at the presumably domestication-related locus functionally differentiate in plant height and seed dormancy. Thus, the evolutionary mechanism of this agriculturally important gene remains open for discussion. PMID:26373662
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The effects of temperature on the dormancy and germination of Cirsium arvense (L. Scop. seeds
Directory of Open Access Journals (Sweden)
Anna Bochenek
2011-01-01
Full Text Available The ecophysiological regulation of seed dormancy in perennial species and those with a varied life cycle has not been studied in detail yet. That is why an attempt has been made to determine the Cirsium arvense seed water relations during stratification and afterripening at different temperatures and germination at constant or fluctuating temperatures on the basis of the hydrotime model. The obtained results showed that breaking of the primary dormancy of achenes took place only during the first stratification month at moderate temperatures, mainly due to an increase in the average water-stress tolerance in a seed population. The induction of secondary seed dormancy during after-ripening at all temperatures resulted mostly from a substantial loss of the seeds' ability to tolerate water stress. Fluctuating temperatures affected neither seed germination nor the hydrotime model parameters. The analysis of the variations of hydrotime model parameters allows a better understanding of the physiological basis of seed dormancy relief and induction.
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Vigor of sunflower and soybean aging seed
Tatić M.; Balešević-Tubić S.; Ðorđević V.; Miklič V.; Vujaković M.; Ðukić V.
2012-01-01
Seed aging and deterioration affect seed vigor and viability. The characteristics of the chemical composition of oil crops seed are related to specific processes occurring in the seed during storage. This study was performed to examine the changes in seed vigor of different sunflower and soybean genotypes under controlled and conventional (uncontrolled) conditions of natural aging for six and twelve months. Obtained results show that the degree of seed dama...
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Dormancy and germination in short-lived lepidium perfoliatu l. (brassicaceae) seeds
International Nuclear Information System (INIS)
Tang, An-Jun; Tian, M.; Long, Chun-Lin
2010-01-01
To understand germination timing in an ecological context, the response to environmental events that effect seed dormancy is central and has to be combined with knowledge of germination responses to different ecological factors. In this study, seed dormancy, germination and seedling survival of annual short-lived clasping pepper weed Lepidium perfoliatum L. (Brassicaceae) were investigated. Three types of pre-treatments viz., various temperature dry storage, light and water stress were tested as possible dormancy and survival-affecting environmental events. Fresh mature seeds were greatly dormant. Warm (30 deg. C) dry storage more facilitated breaking dormancy, they germinated well under apt conditions (e.g. 20 deg. C and 10/20 deg. C plus periodic light, 14 h/d). For those seeds which underwent after-ripening, they could germinate at a range of constant temperatures (4, 10, 15, 20, 25, and 30 deg. C) and one alternating temperature (10/20 deg. C). Under alternating temperature regimes, the final percent germination of L. perfoliatum seeds increased from 37 deg. C to 93% when temperature altered from 4/10 deg. C to 10/20 deg. C in light, then decreased with increasing temperature. The germination pattern under constant temperature conditions was similar to that under alternating temperature and significant differences in final percent germinations and rates of germination were observed among different temperatures. Under different light treatments, final germination of showed significant differences, only with 35% of germination percentage in dark, much lower than those in red and white light (i.e. 93% and 91%, respectively). GA3 could promote the germination of non-dormant seeds in dark. When water potentials were reduced, final percent germination decreased dramatically, and few seeds germinated at -0.98 MPa (generated by PEG-8000). The changes of proline content in resultant seedlings were reverse to that of final percent germination with changing water
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Antioxidant effect of poleo and oregano essential oil on roasted sunflower seeds.
Quiroga, Patricia R; Grosso, Nelson R; Nepote, Valeria
2013-12-01
The objective was to evaluate the stability of sensory and chemical parameters in roasted sunflower seeds supplemented with oregano and poleo essential oils; and the consumer acceptability of this product. Four samples were prepared: plain roasted sunflower seeds (Control = RS-C), and sunflower seeds added with oregano (RS-O) or poleo (RS-P) essential oils or BHT (RS-BHT). Consumer acceptance was determined on fresh samples. The overall acceptance averages were 6.13 for RS-C, 5.62 for RS-P, and 5.50 for RS-O (9-point hedonic scale). The addition of BHT showed greater protection against the oxidation process in the roasted sunflower seeds. Oregano essential oil exhibited a greater antioxidant effect during storage than poleo essential oil. Both essential oils (oregano and poleo) provided protection to the product, inhibiting the formation of undesirable flavors (oxidized and cardboard). The antioxidant activity that presents essential oils of oregano and poleo could be used to preserve roasted sunflower seeds. © 2013 Institute of Food Technologists®
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Effect of some Evaporation Matters on Storability of Sunflower ( Helianthus annuus L.) Seed.
El-Saidy, Aml E A; El-Hai, K M Abd
This study focuses on finding compounds that are safe to humans and environment, such as propionic and acetic acids that may provide an alternative control of seed-borne pathogens and decrease seed deterioration during storage. The objectives of this study were to reduce sunflower seed deterioration and improve the viability of sunflower seed using environmentally safe organic acids. Propionic and acetic acids were applied on sunflower seed at different concentrations under laboratory conditions during different storage periods. After 6 months storage period, the viability of sunflower seed as well as morphological and physiological characteristics of seedlings were evaluated under greenhouse conditions. Laboratory experiment was conducted in a factorial completely randomized design and randomized complete block design for greenhouse experiment. Propionic and acetic acids at different concentrations showed inhibitory effects on the presence of different fungal genera in all storage periods. Propionic acid was most effective followed by acetic acid. Increasing storage periods from 0-6 months significantly decreased germination percentage, germination energy, seedling characters, survived healthy seedlings and seed oil and protein percentages but dead and rotted seeds, as well as rotted seedlings were increased. Treating sunflower seeds with propionic acid (100%) improved germination criteria, seedling characters and seed chemical characters as well as survival seedlings and minimized the dead seeds, rotted seeds and rotted seedlings as compared with the control under all storage periods. Under greenhouse conditions, the maximum growth parameter and physiological characters (chlorophylls a, b, carotenoids and total phenols) were recorded from seed treated with 100% propionic acid after 6 months of storage. It may be concluded that propionic and acetic acids vapors can have considerable fungicidal activity against sunflower pathogens and improve seed viability
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Dormancy break in Pithecellobium dulce (Roxb. Benth. seeds
Directory of Open Access Journals (Sweden)
Francisco Elder Carlos Bezerra Pereira
2015-02-01
Full Text Available This research aimed to evaluate different methods for breaking dormancy in seeds of Pithecellobium dulce (Roxb. Benth., arboreal species of multiple use in the semiarid region of Northeast Brazil. The treatments were: control – intact seeds (T1; immersion in water until it reaches 80 °C (T2, and 100 °C (T3, concentrated sulfuric acid for five minutes (T4, 10 minutes (T5 , and 15 minutes (T6, mechanical scarification with sandpaper number 80 (T7, mechanical scarification with sandpaper number 80 + immersion in water for six hours (T8, and for 12 hours (T9, soaking in water for 24 hours (T10, and for 48 hours (T11. The characteristics evaluated were such: emergency, mean emergency time, shoot length, root length, number of leaves, leaf area and total dry matter. The best method for breaking dormancy of seeds of Pithecellobium dulce (Roxb. Benth. is mechanical scarification with sandpaper number 80.
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Genes controlling seed dormancy and pre-harvest sprouting in a rice-wheat-barley comparison
DEFF Research Database (Denmark)
Li, Chengdao; Ni, Peixiang; Francki, Michael
2004-01-01
Pre-harvest sprouting results in significant economic loss for the grain industry around the world. Lack of adequate seed dormancy is the major reason for pre-harvest sprouting in the field under wet weather conditions. Although this trait is governed by multiple genes it is also highly heritable....... A major QTL controlling both pre-harvest sprouting and seed dormancy has been identified on the long arm of barley chromosome 5H, and it explains over 70% of the phenotypic variation. Comparative genomics approaches among barley, wheat and rice were used to identify candidate gene(s) controlling seed...... dormancy and hence one aspect of pre-harvest sprouting. The barley seed dormancy/pre-harvest sprouting QTL was located in a region that showed good synteny with the terminal end of the long arm of rice chromosome 3. The rice DNA sequences were annotated and a gene encoding GA20-oxidase was identified...
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Rhie, Y H; Lee, S Y; Kim, K S
2015-03-01
The genus Jeffersonia, which contains only two species, has a trans-Atlantic disjunct distribution. The aims of this study were to determine the requirements for breaking dormancy and germination of J. dubia seeds and to compare its dormancy characteristics with those of the congener in eastern North America. Ripe seeds of J. dubia contain an underdeveloped embryo and were permeable to water. In nature, seeds were dispersed in May, while embryos began to grow in September, and were fully elongated by late November. Germination started in March of the next year, and seeds emerged as seedlings soon after germination. In laboratory experiments, incubation at high temperatures (25 °C, 25/15 °C) for at least 8 weeks was required to initiate embryo growth, while a transfer to moderate temperatures (20/10 °C, 15/6 °C) was needed for the completion of embryo growth. At least 8 weeks at 5 °C was effective in overcoming physiological dormancy and for germination in seeds after the embryos had fully elongated. Thus, both high and low temperatures were essential to break dormancy. Gibberellic acid (GA3 ) treatment could substitute for the high temperature requirement, but not for the low temperature requirement. Based on the dormancy-breaking requirements, it is confirmed that the seeds have deep simple morphophysiological dormancy. This dormancy type is similar to that of seeds of the eastern North American species J. diphylla. Although seeds require 10-11 months from seed dispersal to germination in nature, under controlled conditions they required only 3 months after treatment with 1000 mg·l(-1) GA3 , followed by incubation at 15/6 °C. This represents practical knowledge for propagation of these plants from seed. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.
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Utilization of sunflower seed in laying hen rations
Directory of Open Access Journals (Sweden)
Tsuzuki ET
2003-01-01
Full Text Available The objective of this trial was to evaluate the effect of sunflower seed inclusion (0, 1.4, 2.8, 4.2 and 5.6% in a laying hen diet containing corn, soybean meal, wheat meal and soybean oil as main ingredients on performance and egg quality. The evaluated variables were daily feed intake, average egg weight, feed conversion (kg.kg-1 and kg.dz-1, eggshell percentage, yolk color and Haugh unit. One hundred and sixty 25 week-old Lohmann laying hens were used in a completely randomized design with five treatments and four replications of eight birds per experimental unit. Four periods of 28 days were evaluated during 112 days. The inclusion of sunflower seed in the diet had no effect on production parameters during the experimental period. Thus, can be concluded that sunflower seed might be used at concentrations up to 5.6% in laying hen diets without affecting performance and egg quality.
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Maturation, temperature and breaking dormancy of Comanthera seeds
Andréa Santos Oliveira; Maria Laene Moreira Carvalho; Cláudio das Neves Vieira Bárbara; Tanismare Tatiana Almeida; Marcela Carlota Nery
2016-01-01
Given the importance of “everlasting” plants for their ornamental value and vulnerability to extractive practices, studies to ensure the propagation of the species are indispensable. The aim of this study was to assess whether there is an association between seed coat color and the quality of everlasting seeds, in the presence or absence of dormancy. Four species (Comanthera elegans, C. nitida, C. bisculata, and Comanthera sp.) were separated with respect to seed coat color and underwent germ...
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OVERCOMING SEED DORMANCY IN Annona macroprophyllata AND Annona purpureaUSING PLANT GROWTH REGULATORS
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GISELA FERREIRA
Full Text Available ABSTRACT Some Annonaceae seeds are known to exhibit dormancy mechanisms ranging from possible seed coat impermeability to physiological dormancy. Thus, the aim of this study was to evaluate the effects of gibberellin (GA GA3 and GA4+7 + benzyladenine (GA4+7 + BA application in seeds of Annona macroprophyllata Donn. Sm (papausa and Annona purpurea Moc. & Sessé ex Dunal (chincuya. The experiment was performed by the application of GA3 and GA4+7 + BA on seeds in concentrations of 0, 200, 400, 500, 600, 800 and 1000 mg L-1. The regulators broke the dormancy of both species. However, application of the GA4+7 + BA mixture had more significant results, with greater increases in germination in A. macroprophyllata than in A. purpurea. Treatments that promoted the highest germinations were GA4+7 + BA at a concentration of 200 mg L-1 for A. macroprophyllata (77% and 200 mg L-1 of GA4+7 + BA and 500 mg L-1 of GA3 for A. purpurea (30% and 29%, respectively. Rate index, mean time and frequency of germination were distinct for both species and both treatments. Although both GA3 and GA4+7 + BA promote germination, the GA4+7 + BA mixture was more effective than GA3 to overcoming seed dormancy of both species, A. purpurea has a harder dormancy than A. macroprophyllata
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Physical properties of sunflower seeds during drying
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Thaís Adriana de Souza Smaniotto
2017-03-01
Full Text Available The aim of this work was to determine the effect that the moisture content has on the physical properties of sunflower seeds. The cultivar Olisun 3, with an initial moisture content of 34.1 (% wb, was used and then subjected to drying in an oven with forced air ventilation under three temperature conditions: 40, 60 and 80 °C. The reduction in the moisture content during drying was monitored by the gravimetric method until it reached a final moisture content of 8.0 ± 1.0 (% wb. The physical properties were analysed: the bulk density, true density, intergranular porosity and volumetric shrinkage of the mass and unit and terminal velocity. The reduction in the moisture content influenced the physical properties of sunflower seeds and caused a decrease in the intergranular porosity, bulk density and true density at all examined temperatures. The mass and volumetric contractions of the unit and reduction in shrinkage rates all increased with the drying of sunflower seeds at all studied temperatures. The terminal velocity increased as the moisture content of the grains increased, which was more evident at the drying temperature of 80 °C.
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IMPORTANCE OF STORAGE CONDITIONS AND SEED TREATMENT FOR SUNFLOWER HYBRIDS SEEDS GERMINATION
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Goran Krizmanić
2014-12-01
Full Text Available In this research we have determined germination energy and germination of seeds of sunflower hybrids ‘Luka’ and ‘Apolon’, at the beginning of storage and 6, 12 and 18 months after of storage period (2011-2012 in the floor concrete storage at two different air temperatures and humidity (S-1: air temperature 15-18°C and relative air humidity 65-70% as well as in climate chamber (S-2: air temperature 10-12°C and relative air humidity 60-65%, stored in four treatments (Control: processed-untreated seed; T-1: treated with A.I. metalaxyl-M; T-2: treated with A.I. metalaxyl-M + A.I. imidacloprid and T-3: treated with A.I. metalaxyl-M + A.I. clothianidin. Based on the obtained results we have determined that sunflower hybrid ‘Luka’, compared to hybrid ‘Apolon’, in the given storage conditions and with the same seed treatment has 5-8% higher germination energy and seed germination and that in climate chamber both hybrids have 5-7% higher germination energy. Seed treatment of both sunflower hybrids with A.I. imidacloprid maximally reduced initial germination energy and seed germination in all tested periods and conditions of storage. On the average, natural seed, after 18 months of storage did not have better seed quality compared to seed treated with A.I. metalaxyl-M while other treatments had more significant influence on reduction of germination energy and seed germination, 6-15%. On the average, compared to other variants, seeds treated with A.I. metalaxyl-M after 18 months of storage in both storage conditions had higher germination energy by 4-15%, and seed germination by 2-12%.
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Sunflower seed: a potential source of food and feed products
International Nuclear Information System (INIS)
Kausar, T.; Ali, S.; Javed, M.A.; Javad, M.A.
2004-01-01
Chemical composition of seven varieties of sunflower seeds and seed fractions i.e., kernels, hulls and meals was determined. Sunflower meals (SFM) contained 44.00 to 49.52% crude protein, 1.25 to 1.50% fat, 3.43 to 6.75% crude fibre, 7.50 to 8.51% ash, 27.30 to 36.09% nitrogen free extract, 3.12 to 3.51% phytic acid and 2.45 to 3.01% chlorogenic acid. Fatty acid profile of sunflower oil with respect to other vegetable oils (i.e., soybean, mustard, canola, cotton, corn oils) and protein solubility profile of sunflower meal as compared to soybean and mustard meals, indicate that its oil and meal have a great nutritional potential. (author)
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NITRIC OXIDE IMPLICATION IN THE CONTROL OF SEED DORMANCY AND GERMINATION
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Erwann eArc
2013-09-01
Full Text Available Germination ability is regulated by a combination of environmental and endogenous signals with both synergistic and antagonistic effects. Nitric oxide (NO is a potent dormancy-releasing agent in many species, including Arabidopsis, and has been suggested to behave as an endogenous regulator of this physiological blockage. Distinct reports have also highlighted a positive impact of NO on seed germination under sub-optimal conditions. However, its molecular mode of action in the context of seed biology remains poorly documented. This review aims to focus on the implications of this radical in the control of seed dormancy and germination. The consequences of NO chemistry on the investigations on both its signaling and its targets in seeds are discussed. NO-dependant protein post-translational modifications are proposed as a key mechanism underlying NO signalling during early seed germination.
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Directory of Open Access Journals (Sweden)
Aihua Liu
Full Text Available Treatments that promote dormancy release are often correlated with changes in seed hormone content and/or sensitivity. To understand the molecular mechanisms underlying the role of after-ripening (seed dry storage in triggering hormone related changes and dormancy decay in wheat (Triticum aestivum, temporal expression patterns of genes related to abscisic acid (ABA, gibberellin (GA, jasmonate and indole acetic acid (IAA metabolism and signaling, and levels of the respective hormones were examined in dormant and after-ripened seeds in both dry and imbibed states. After-ripening mediated developmental switch from dormancy to germination appears to be associated with declines in seed sensitivity to ABA and IAA, which are mediated by transcriptional repressions of PROTEIN PHOSPHATASE 2C, SNF1-RELATED PROTEIN KINASE2, ABA INSENSITIVE5 and LIPID PHOSPHATE PHOSPHTASE2, and AUXIN RESPONSE FACTOR and RELATED TO UBIQUITIN1 genes. Transcriptomic analysis of wheat seed responsiveness to ABA suggests that ABA inhibits the germination of wheat seeds partly by repressing the transcription of genes related to chromatin assembly and cell wall modification, and activating that of GA catabolic genes. After-ripening induced seed dormancy decay in wheat is also associated with the modulation of seed IAA and jasmonate contents. Transcriptional control of members of the ALLENE OXIDE SYNTHASE, 3-KETOACYL COENZYME A THIOLASE, LIPOXYGENASE and 12-OXOPHYTODIENOATE REDUCTASE gene families appears to regulate seed jasmonate levels. Changes in the expression of GA biosynthesis genes, GA 20-OXIDASE and GA 3-OXIDASE, in response to after-ripening implicate this hormone in enhancing dormancy release and germination. These findings have important implications in the dissection of molecular mechanisms underlying regulation of seed dormancy in cereals.
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Directory of Open Access Journals (Sweden)
Ming lei Zhao
2015-03-01
Full Text Available Seed dormancy controls germination and plays a critical role in regulating the beginning of the life cycle of plants. Seed dormancy is established and maintained during seed maturation and is gradually broken during dry storage (after-ripening. The plant hormone abscisic acid (ABA and DELAY OF GERMINATION1 (DOG1 protein are essential regulators of seed dormancy. Recent studies revealed that chromatin modifications are also involved in the transcription regulation of seed dormancy. Here, we showed that two Arabidopsis histone demethylases, LYSINESPECIFIC DEMETHYLASE LIKE 1 and 2 (LDL1 and LDL2 act redundantly in repressing of seed dormancy. LDL1 and LDL2 are highly expressed in the early silique developing stage. The ldl1 ldl2 double mutant displays increased seed dormancy, whereas overexpression of LDL1 or LDL2 in Arabidopsis causes reduced dormancy. Furthermore, we showed that LDL1 and LDL2 repress the expression of seed dormancy-related genes, including DOG1, ABA2 and ABI3 during seed dormancy establishment. Furthermore, genetic analysis revealed that the repression of seed dormancy by LDL1 and LDL2 requires DOG1, ABA2 and ABI3. Taken together, our findings revealed that LDL1 and LDL2 play an essential role in seed dormancy.
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Medicago Scutellata Seed Dormancy Breaking by Ultrasonic Waves
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Nazari Meisam
2014-12-01
Full Text Available In this study dormancy breaking of a hard-coated plant seed, Medicago scutellata, was investigated. The ultrasonic waves effect on the seed germination percentage, germination rate, radicle length and stalk length growth was assessed. Six treatments of waves exposure periods including 0, 1, 3, 5, 7, and 9 minutes were tested under laboratorial conditions. Statistical analyses were done at probability level of 0.01. Results revealed that the ultrasonic waves have a significantly positive effect on the seed dormancy breaking, but there was no linear correlation between the increasing times of exposure with any of the growth features. The best treatment for germination percentage and germination rate was the 7-minute one and the 3-minute one was the best for radicle length growth. Treatments of 3, 5 and 7 minutes had the same effect on stalk length growth and were better than all other treatments. The 9-minute treatment had a negative effect, even lessening the growth of all of the assessed features in comparison with the control treatment.
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The role of the testa during development and in establishment of dormancy of the legume seed
Smýkal, Petr; Vernoud, Vanessa; Blair, Matthew W.; Soukup, Aleš; Thompson, Richard D.
2014-01-01
Timing of seed germination is one of the key steps in plant life cycles. It determines the beginning of plant growth in natural or agricultural ecosystems. In the wild, many seeds exhibit dormancy and will only germinate after exposure to certain environmental conditions. In contrast, crop seeds germinate as soon as they are imbibed usually at planting time. These domestication-triggered changes represent adaptations to cultivation and human harvesting. Germination is one of the common sets of traits recorded in different crops and termed the “domestication syndrome.” Moreover, legume seed imbibition has a crucial role in cooking properties. Different seed dormancy classes exist among plant species. Physical dormancy (often called hardseededness), as found in legumes, involves the development of a water-impermeable seed coat, caused by the presence of phenolics- and suberin-impregnated layers of palisade cells. The dormancy release mechanism primarily involves seed responses to temperature changes in the habitat, resulting in testa permeability to water. The underlying genetic controls in legumes have not been identified yet. However, positive correlation was shown between phenolics content (e.g., pigmentation), the requirement for oxidation and the activity of catechol oxidase in relation to pea seed dormancy, while epicatechin levels showed a significant positive correlation with soybean hardseededness. myeloblastosis family of transcription factors, WD40 proteins and enzymes of the anthocyanin biosynthesis pathway were involved in seed testa color in soybean, pea and Medicago, but were not tested directly in relation to seed dormancy. These phenolic compounds play important roles in defense against pathogens, as well as affecting the nutritional quality of products, and because of their health benefits, they are of industrial and medicinal interest. In this review, we discuss the role of the testa in mediating legume seed germination, with a focus on
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Dormancy-breaking requirements of Sophora tomentosa and Erythrina speciosa (Fabaceae seeds
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Carolina Maria Luzia Delgado
2015-03-01
Full Text Available The physical dormancy of seeds has been poorly studied in species from tropical forests, such as the Atlantic Forest. This study aimed to examine the effect of moderate alternating temperatures on breaking the physical dormancy of seeds, the morphoanatomy and histochemistry of seed coats, and to locate the structure/region responsible for water entrance into the seed, after breaking the physical dormancy of seeds of two woody Fabaceae (subfamily Faboideae species that occur in the Brazilian Atlantic Forest: Sophora tomentosa and Erythrina speciosa. To assess temperature effect, seeds were incubated in several temperature values that occur in the Atlantic Forest. For morphological and histochemical studies, sections of fixed seeds were subjected to different reagents, and were observed using light or epifluorescence microscopy, to analyze the anatomy and histochemistry of the seed coat. Treated and non-treated seeds were also analyzed using a scanning electron microscope (SEM to observe the morphology of the seed coat. To localize the specific site of water entrance, the seeds were blocked with glue in different regions and also immersed in ink. In the present work a maximum temperature fluctuation of 15ºC was applied during a period of 20 days and these conditions did not increase the germination of S. tomentosa or E. speciosa. These results may indicate that these seeds require larger fluctuation of temperature than the applied or/and longer period of exposition to the temperature fluctuation. Blocking experiments water inlet combined with SEM analysis of the structures of seed coat for both species showed that besides the lens, the hilum and micropyle are involved in water absorption in seeds scarified with hot water. In seeds of E. speciosa the immersion of scarified seeds into an aniline aqueous solution showed that the solution first entered the seed through the hilum. Both species showed seed morphological and anatomical features for seed
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Loss of sunflower seeds to columbids in South Africa: economic ...
African Journals Online (AJOL)
A survey across the sunflower production region of South Africa during November 2003 to July 2005 estimated the loss of sunflower seeds to columbids (doves and pigeons, Aves: Columbidae). Farmers estimated that 12.7% of the national yield was lost to columbids. In a follow-up survey, 37 sunflower fields were visited ...
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Hormonal Regulation of Dormancy in Developing Sorghum Seeds.
Steinbach, H. S.; Benech-Arnold, R. L.; Sanchez, R. A.
1997-01-01
The role of abscisic acid (ABA) and gibberellic acid (GA) in determining the dormancy level of developing sorghum (Sorghum bicolor [L.] Moench.) seeds from varieties presenting contrasting preharvest sprouting behavior (Redland B2, susceptible; IS 9530, resistant) was investigated. Panicles from both varieties were sprayed soon after pollination with fluridone or paclobutrazol to inhibit ABA and GA synthesis, respectively. Fluridone application to the panicles increased germinability of Redland B2 immature caryopses, whereas early treatment with paclobutrazol completely inhibited germination of this variety during most of the developmental period. Incubating caryopses in the presence of 100 [mu]M GA4+7 overcame the inhibitory effect of paclobutrazol, but also stimulated germination of seeds from other treatments. IS 9530 caryopses presented germination indices close to zero until physiological maturity (44 d after pollination) in control and paclobutrazol-treated particles. However, fluridone-treated caryopses were released from dormancy earlier than control and paclobutrazol-treated caryopses. Incubation in the presence of GA4+7 stimulated germination of caryopses from all treatments. Our results support the proposition that a low dormancy level (which is related to a high preharvest sprouting susceptibility) is determined not only by a low embryonic sensitivity to ABA, but also by a high GA content or sensitivity.
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Involvement of ABA in induction of secondary dormancy in barley (Hordeum vulgare L.) seeds.
Leymarie, Juliette; Robayo-Romero, Maria Emilia; Gendreau, Emmanuel; Benech-Arnold, Roberto L; Corbineau, Françoise
2008-12-01
At harvest, barley seeds are dormant because their germination is difficult above 20 degrees C. Incubation of primary dormant seeds at 30 degrees C, a temperature at which they do not germinate, results in a loss of their ability to germinate at 20 degrees C. This phenomenon which corresponds to an induction of a secondary dormancy is already observed after a pre-treatment at 30 degrees C as short as 4-6 h, and is optimal after 24-48 h. It is associated with maintenance of a high level of embryo ABA content during seed incubation at 30 degrees C, and after seed transfer at 20 degrees C, while ABA content decreases rapidly in embryos of primary dormant seeds placed directly at 20 degrees C. Induction of secondary dormancy also results in an increase in embryo responsiveness to ABA at 20 degrees C. Application of ABA during seed treatment at 30 degrees C has no significant additive effect on the further germination at 20 degrees C. In contrast, incubation of primary dormant seeds at 20 degrees C for 48 and 72 h in the presence of ABA inhibits further germination on water similarly to 24-48 h incubation at 30 degrees C. However fluridone, an inhibitor of ABA synthesis, applied during incubation of the grains at 30 degrees C has only a slight effect on ABA content and secondary dormancy. Expression of genes involved in ABA metabolism (HvABA8'OH-1, HvNCED1 and HvNCED2) was studied in relation to the expression of primary and secondary dormancies. The results presented suggest a specific role for HvNCED1 and HvNCED2 in regulation of ABA synthesis in secondary seed dormancy.
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Pawłowski, Tomasz A
2009-05-04
Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA) and gibberellic (GA) acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent state to germination. Seed dormancy breaking involves
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Directory of Open Access Journals (Sweden)
Pawłowski Tomasz A
2009-05-01
Full Text Available Abstract Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid and growth promoters (e.g. gibberellins is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA and gibberellic (GA acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent
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Methods to overcome dormancy in tree tomato (Solanum betaceum seeds
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Carlos Kosera Neto
2015-12-01
Full Text Available The tree tomato (Solanum betaceum is a poorly known species that has fruits with great economic potential, as it can be consumed in natura or industrialized. However, for reaching this potential, it is necessary the development of technologies for seedlings production. The propagation of this species is mainly done by seeds, but the seed germination process is usually slow, especially under stress conditions. This study aimed at verifying whether tree tomato seeds have dormancy and which is the best method to obtain fast and uniform germination. A completely randomized design was adopted in a 5 x 2 factorial arrangement (methods to overcome dormancy x light, with four replications of 50 or 60 seeds, depending on the production cycle. The methods tested were cold stratification, hydropriming, priming with GA3 solution and control, with or without light. Seed germination and germination rate index, as well as the beginning and average time of germination, were also evaluated. The use of GA3 at a concentration of 100 mg L-1 or 300 mg L-1 is recommended to the germination of tree tomato seeds.
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Inheritance of fresh seed dormancy in Spanish-type peanut ( Arachis ...
African Journals Online (AJOL)
Production and seed quality in peanut (Arachis hypogaea L.) can be reduced substantially by in situ germination under unpredictable rainfed environments. Inheritance of fresh seed dormancy in Spanish x Spanish crosses was studied with two sets of segregating populations, an F2 population derived from true F1 hybrids ...
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Cadman, Cassandra S C; Toorop, Peter E; Hilhorst, Henk W M; Finch-Savage, William E
2006-06-01
Physiologically dormant seeds, like those of Arabidopsis, will cycle through dormant states as seasons change until the environment is favourable for seedling establishment. This phenomenon is widespread in the plant kingdom, but has not been studied at the molecular level. Full-genome microarrays were used for a global transcript analysis of Arabidopsis thaliana (accession Cvi) seeds in a range of dormant and dry after-ripened states during cycling. Principal component analysis of the expression patterns observed showed that they differed in newly imbibed primary dormant seeds, as commonly used in experimental studies, compared with those in the maintained primary and secondary dormant states that exist during cycling. Dormant and after-ripened seeds appear to have equally active although distinct gene expression programmes, dormant seeds having greatly reduced gene expression associated with protein synthesis, potentially controlling the completion of germination. A core set of 442 genes were identified that had higher expression in all dormant states compared with after-ripened states. Abscisic acid (ABA) responsive elements were significantly over-represented in this set of genes the expression of which was enhanced when multiple copies of the elements were present. ABA regulation of dormancy was further supported by expression patterns of key genes in ABA synthesis/catabolism, and dormancy loss in the presence of fluridone. The data support an ABA-gibberelic acid hormone balance mechanism controlling cycling through dormant states that depends on synthetic and catabolic pathways of both hormones. Many of the most highly expressed genes in dormant states were stress-related even in the absence of abiotic stress, indicating that ABA, stress and dormancy responses overlap significantly at the transcriptome level.
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Footitt, Steven; Ölçer-Footitt, Hülya; Hambidge, Angela J; Finch-Savage, William E
2017-08-01
Environmental signals drive seed dormancy cycling in the soil to synchronize germination with the optimal time of year, a process essential for species' fitness and survival. Previous correlation of transcription profiles in exhumed seeds with annual environmental signals revealed the coordination of dormancy-regulating mechanisms with the soil environment. Here, we developed a rapid and robust laboratory dormancy cycling simulation. The utility of this simulation was tested in two ways: firstly, using mutants in known dormancy-related genes [DELAY OF GERMINATION 1 (DOG1), MOTHER OF FLOWERING TIME (MFT), CBL-INTERACTING PROTEIN KINASE 23 (CIPK23) and PHYTOCHROME A (PHYA)] and secondly, using further mutants, we test the hypothesis that components of the circadian clock are involved in coordination of the annual seed dormancy cycle. The rate of dormancy induction and relief differed in all lines tested. In the mutants, dog1-2 and mft2, dormancy induction was reduced but not absent. DOG1 is not absolutely required for dormancy. In cipk23 and phyA dormancy, induction was accelerated. Involvement of the clock in dormancy cycling was clear when mutants in the morning and evening loops of the clock were compared. Dormancy induction was faster when the morning loop was compromised and delayed when the evening loop was compromised. © 2017 The Authors Plant, Cell & Environment Published by John Wiley & Sons Ltd.
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Changes of fatty acids content and vigor of sunflower seed during natural aging
Balešević-Tubić S.; Tatić M.; Miladinović J.; Pucarević M.
2007-01-01
Sunflower seed aging during storage affects seed vigor and content of fatty acids. In order to reveal severity of their influence, the following vigor tests were applied: standard laboratory germination test, cold test and Hiltner test. Five sunflower lines submitted to natural aging process for six and 12 months were tested under conventional storage and controlled conditions. The obtained results revealed that seed aging damaged the seed, which adversely affected seed vigor; most reliable r...
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Induction of 9-cis-epoxycarotenoid dioxygenase in Arabidopsis thaliana seeds enhances seed dormancy
Martínez-Andújar, Cristina; Ordiz, M. Isabel; Huang, Zhonglian; Nonogaki, Mariko; Beachy, Roger N.; Nonogaki, Hiroyuki
2011-01-01
Full understanding of mechanisms that control seed dormancy and germination remains elusive. Whereas it has been proposed that translational control plays a predominant role in germination, other studies suggest the importance of specific gene expression patterns in imbibed seeds. Transgenic plants were developed to permit conditional expression of a gene encoding 9-cis-epoxycarotenoid dioxygenase 6 (NCED6), a rate-limiting enzyme in abscisic acid (ABA) biosynthesis, using the ecdysone recept...
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High trees increase sunflower seed predation by birds in an agricultural landscape of Israel
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Jessica eSchäckermann
2014-07-01
Full Text Available Natural habitats in agricultural landscapes promote agro-ecosystem services but little is known about negative effects (dis-services derived by natural habitats such as crop seed predation. Birds are important seed predators and use high landscape structures to perch and hide. High trees in agricultural landscapes may therefore drive seed predation. We examined if the presence, the distance and the percentages of high trees (tree height >5 m and the percentages of natural habitat surrounding sunflower fields, increased seed predation by birds in Israel. At the field scale, we assessed seed predation across a sample grid of an entire field. At the landscape scale, we assessed seed predation at the field margins and interiors of 20 sunflower fields. Seed predation was estimated as the percentage of removed seeds from sunflower heads. Distances of sample points to the closest high tree and percentage of natural habitat and of high trees in a 1km radius surrounding the fields were measured.We found that seed predation increased with decreasing distance to the closest high tree at the field and landscape scale. At the landscape scale, the percentage of high trees and natural habitat did not increase seed predation. Seed predation in the fields increased by 37 %, with a maximum seed predation of 92 %, when a high tree was available within zero to 50 m to the sunflower fields. If the closest high tree was further away, seed predation was less than 5 %. Sunflower seed predation by birds can be reduced, when avoiding sowing sunflowers within a radius of 50 m to high trees. Farmers should plan to grow crops, not sensitive to bird seed predation, closer to trees to eventually benefit from ecosystem services provided by birds, such as predation of pest insects, while avoiding these locations for growing crops sensitive to bird seed predation. Such management recommendations are directing towards sustainable agricultural landscapes.
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Directory of Open Access Journals (Sweden)
Anna Bochenek
2011-01-01
Full Text Available Changes in hydrotime model parameters were determined in Matricaria maritima L. subsp. inodora seeds during burial in a field in order to describe the seasonal dormancy pattern. Seeds were exhumed at regular intervals over a year and incubated at different water potentials at 19°C. Germination time courses were analyzed to determine hydrotime population parameters. Values of ѱb(50, ѲH and σѱb varied each month. Mean base water potential values in seeds exhumed each month were related to precipitation over 20 days before their exhumation. Soil temperature could be a trend-controlling factor of this relationship. The seeds were in deep dormancy after remaining 80-90 days in soil below or above limit temperature 15°C. The application of the hydrotime model to describe and predict seasonal dormancy patterns of weed seed is promising, especially for species with a considerable diversification of life strategies and ecophysiological flexibility of diaspores. It could also suggest mechanisms of seasonal dormancy changes of seeds in natural conditions and provide a basis for their examination. One of advantages of the dormancy pattern description of weed seeds remaining in a soil bank by means of threshold models is its simplicity.
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SCHÜTZ, W.; MILBERG, P.; LAMONT, B. B.
2002-01-01
The role of dormancy, temperature and light in the regulation of seed germination of four annual Asteraceae from south‐western Australia was investigated. The experiments aimed to identify after‐ripening patterns, and to relate these to climatic conditions of the habitat in which the species occur. Seeds of all species were strongly dormant at maturity and maintained high levels of dormancy for time periods corresponding to the duration of summer in south‐western Australia. Dry after‐ripening was promoted best by temperatures lower than those prevailing in the dry season, although differences among storage temperatures were mostly insignificant. Germination percentages were highest at average winter temperatures (15 °C). A logistic model revealed significant differences in germinability among species, but not between incubation temperatures or light and dark treatments across species. Three species with seeds >0·5 mg germinated better in darkness than in light, whereas germination in darkness was almost inhibited in the species with the smallest seeds (0·14 mg). The course of dormancy loss, tested over a range of fluctuating incubation temperatures (7–30 °C), showed that seeds of three species came out of dormancy first at temperatures that prevail in south‐western Australia during the winter (10–15 °C). Seeds from one species, introduced from South Africa, first lost dormancy at the lowest temperature (7 °C). All species showed after‐ripening patterns of Type 1, typical of species growing in Mediterranean climates. The germination characteristics of the investigated species can be interpreted as ensuring that initial growth and establishment occur during the winter growing season, thereby avoiding the hot and dry summer conditions that follow seed dispersal. PMID:12451026
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Du, W; Cheng, J; Cheng, Y; Wang, L; He, Y; Wang, Z; Zhang, H
2015-11-01
After-ripening is a common method used for dormancy release in rice. In this study, the rice variety Jiucaiqing (Oryza sativa L. subsp. japonica) was used to determine dormancy release following different after-ripening times (1, 2 and 3 months). Germination speed, germination percentage and seedling emergence increased with after-ripening; more than 95% germination and 85% seedling emergence were observed following 1 month of after-ripening within 10 days of imbibition, compared with rice dormancy release. Dormancy release by after-ripening is mainly correlated with a rapid decline in ABA content and increase in IAA content during imbibition. Subsequently, GA(1)/ABA, GA(7)/ABA, GA(12)/ABA, GA(20)/ABA and IAA/ABA ratios significantly increased, while GA(3)/ABA, GA(4)/ABA and GAs/IAA ratio significantly decreased in imbibed seeds following 3 months of after-ripening, thereby altering α-amylase activity during seed germination. Peak α-amylase activity occurred at an earlier germination stage in after-ripened seeds than in freshly harvested seeds. Expression of ABA, GA and IAA metabolism genes and dormancy-related genes was regulated by after-ripening time upon imbibition. Expression of OsCYP707A5, OsGA2ox1, OsGA2ox2, OsGA2ox3, OsILR1, OsGH3-2, qLTG3-1 and OsVP1 increased, while expression of Sdr4 decreased in imbibed seeds following 3 months of after-ripening. Dormancy release through after-ripening might be involved in weakening tissues covering the embryo via qLTG3-1 and decreased ABA signalling and sensitivity via Sdr4 and OsVP1. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.
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Ren, C; Kermode, A R
2000-09-01
Pectin methyl esterase (PME) (EC 3.1.1.11) catalyzes the hydrolysis of methylester groups of cell wall pectins. We investigated the role of this enzyme in dormancy termination and germination of yellow cedar (Chamaecyparis nootkatensis [D. Don] Spach) seeds. PME activity was not detected in dormant seeds of yellow cedar but was induced and gradually increased during moist chilling; high activity coincided with dormancy breakage and germination. PME activity was positively correlated to the degree of dormancy breakage of yellow cedar seeds. The enzyme produced in different seed parts and in seeds at different times during moist chilling, germination, and early post-germinative growth consisted of two isoforms, both basic with isoelectric points of 8.7 and 8.9 and the same molecular mass of 62 kD. The pH optimum for the enzyme was between 7.4 and 8.4. In intact yellow cedar seeds, activities of the two basic isoforms of PME that were induced in embryos and in megagametophytes following dormancy breakage were significantly suppressed by abscisic acid. Gibberellic acid had a stimulatory effect on the activities of these isoforms in embryos and megagametophytes of intact seeds at the germinative stage. We hypothesize that PME plays a role in weakening of the megagametophyte, allowing radicle emergence and the completion of germination.
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Influence of the testa on seed dormancy, germination and longevity in Arabidopsis
Debeaujon, I.; Léon-Kloosterziel, K.M.; Koornneef, M.
2000-01-01
The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by limiting the detrimental activity of physical and biological agents during seed storage. To analyze the function of
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Identification and functional analyses of genes regulating seed dormancy, longevity and germination
Yazdanpanah, Farzaneh
2018-01-01
Fundamental knowledge about the processes affecting seed performance, including the regulation of germination, dormancy and longevity can provide insight to improve these traits, which is of economic importance for agricultural use and storage of seed crops. Accordingly, the objective of this
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Directory of Open Access Journals (Sweden)
marzie mazhari
2017-01-01
Full Text Available Introduction: Weeds limit crops growth, development and yield through adjacency and competing and seed dormancy is a problem in controlling of weeds. Man has been always tried to optimize crop yield through weeds controlling. Weeds seed bank in the soil can affected weed management and their control methods. So identifying seed bank characters has important role in choice of management methods in seeds of many plant species which cannot germinate despite favorable environmental conditions. Main reasons for this problem, which is termed as seed dormancy, are hard and impermeable seed coat and presence of immature or dormant embryo. To break dormancy, a variety of methods are in vogue worldwide these days. Of all different methods of breaking dormancy, treatment of seed with certain chemicals including different types of plant growth regulators (PGRs is contemplated as the most effective one. Gibberellic acid (GA3 is the most widely used PGR to improve seed germination in different plant species. Also, nitrate (such as KNO3 clearly stimulates the germination of dormant seeds. KNO3 is the most widely used chemical for promoting germination. Solutions of KNO3 are common in routine germination testing and are recommended by the Association of Official Seed Analysts and the International Seed Testing Association (ISTA for germination tests of many species.Stratification refers to the method of placing seeds in layers alternating with layers of a moisture retaining medium, such as sand, peat or vermiculite, and keeping them at a cool temperature for a certain period, but it varies considerably from species to species. The combination of high moisture and low temperature appears to trigger off biochemical changes which transform complex food substances into simpler forms utilized by the embryo when it renews growth at germination. The use of the word “stratification” has recently been extended to include all forms of cold, moist treatment whether or
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Bernareggi, Giulietta; Carbognani, Michele; Mondoni, Andrea; Petraglia, Alessandro
2016-01-01
Background and Aims Climate warming has major impacts on seed germination of several alpine species, hence on their regeneration capacity. Most studies have investigated the effects of warming after seed dispersal, and little is known about the effects a warmer parental environment may have on germination and dormancy of the seed progeny. Nevertheless, temperatures during seed development and maturation could alter the state of dormancy, affecting the timing of emergence and seedling survival. Here, the interplay between pre- and post-dispersal temperatures driving seed dormancy release and germination requirements of alpine plants were investigated. Methods Three plant species inhabiting alpine snowbeds were exposed to an artificial warming treatment (i.e. +1·5 K) and to natural conditions in the field. Seeds produced were exposed to six different periods of cold stratification (0, 2, 4, 8, 12 and 20 weeks at 0 °C), followed by four incubation temperatures (5, 10, 15 and 20 °C) for germination testing. Key Results A warmer parental environment produced either no or a significant increase in germination, depending on the duration of cold stratification, incubation temperatures and their interaction. In contrast, the speed of germination was less sensitive to changes in the parental environment. Moreover, the effects of warming appeared to be linked to the level of (physiological) seed dormancy, with deeper dormant species showing major changes in response to incubation temperatures and less dormant species in response to cold stratification periods. Conclusions Plants developed under warmer climates will produce seeds with changed germination responses to temperature and/or cold stratification, but the extent of these changes across species could be driven by seed dormancy traits. Transgenerational plastic adjustments of seed germination and dormancy shown here may result from increased seed viability, reduced primary and secondary dormancy state, or both, and
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Janda, Katarzyna; Wolska, Jolanta; Debia, Kamila
2015-01-01
The aim of study was to estimate the qualitative and quantitative composition of moulds colonizing sunflower seeds on RBCA, YpSs, DG18 media at 25, 37, and 45°C. Twenty samples of sunflower seeds (not roasted and not salted) were used for the analysis. The highest number of moulds were xerophilic species isolated on DG18 at 25°C (33), followed by mesophilic species (29) on RBCA medium at 25°C, and mesophilic (22) and thermophilic species (10) on YpSs medium at 37, and 45°C, respectively. Eurotium herbariorum was isolated from all samples. A total of 287 strains belonging to 52 mould species were isolated from sunflower seeds. The study revealed new species not previously isolated from sunflower seeds mycobiota.
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Is gene transcription involved in seed dry after-ripening?
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Patrice Meimoun
Full Text Available Orthodox seeds are living organisms that survive anhydrobiosis and may display dormancy, an inability to germinate at harvest. Seed germination potential can be acquired during a prolonged period of dry storage called after-ripening. The aim of this work was to determine if gene transcription is an underlying regulatory mechanism for dormancy alleviation during after-ripening. To identify changes in gene transcription strictly associated with the acquisition of germination potential but not with storage, we used seed storage at low relative humidity that maintains dormancy as control. Transcriptome profiling was performed using DNA microarray to compare change in gene transcript abundance between dormant (D, after-ripened non-dormant (ND and after-ripened dormant seeds (control, C. Quantitative real-time polymerase chain reaction (qPCR was used to confirm gene expression. Comparison between D and ND showed the differential expression of 115 probesets at cut-off values of two-fold change (p<0.05. Comparisons between both D and C with ND in transcript abundance showed that only 13 transcripts, among 115, could be specific to dormancy alleviation. qPCR confirms the expression pattern of these transcripts but without significant variation between conditions. Here we show that sunflower seed dormancy alleviation in the dry state is not related to regulated changes in gene expression.
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Overcoming dormancy and enhancing germination of Sphaeralcea munroana seeds
Olga A. Kildisheva; R. Kasten Dumroese; Anthony S. Davis
2011-01-01
The results of a series of experiments involving a variety of dormancy-breaking treatments indicate that Munro's globemallow [Sphaeralcea munroana (Douglas) Spach] seeds are physically dormant, possess a cap-like structure in the occlusion of the water gap, which inhibits imbibition, and can be artificially dislodged through boiling water scarification. The...
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Goggin, Danica E; Emery, R J Neil; Kurepin, Leonid V; Powles, Stephen B
2015-02-01
Dormancy in Lolium rigidum (annual ryegrass) seeds can be alleviated by warm stratification in the dark or by application of fluridone, an inhibitor of plant abscisic acid (ABA) biosynthesis via phytoene desaturase. However, germination and absolute ABA concentration are not particularly strongly correlated. The aim of this study was to determine if cytokinins of both plant and bacterial origin are involved in mediating dormancy status and in the response to fluridone. Seeds with normal or greatly decreased (by dry heat pre-treatment) bacterial populations were stratified in the light or dark and in the presence or absence of fluridone in order to modify their dormancy status. Germination was assessed and seed cytokinin concentration and composition were measured in embryo-containing or embryo-free seed portions. Seeds lacking bacteria were no longer able to lose dormancy in the dark unless supplied with exogenous gibberellin or fluridone. Although these seeds showed a dramatic switch from active cytokinin free bases to O-glucosylated storage forms, the concentrations of individual cytokinin species were only weakly correlated to dormancy status. However, cytokinins of apparently bacterial origin were affected by fluridone and light treatment of the seeds. It is probable that resident microflora contribute to dormancy status in L. rigidum seeds via a complex interaction between hormones of both plant and bacterial origin. This interaction needs to be taken into account in studies on endogenous seed hormones or the response of seeds to plant growth regulators. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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A laboratory simulation of the carbonization of sunflower achenes and seeds
Energy Technology Data Exchange (ETDEWEB)
Braadbaart, F. [FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam (Netherlands); Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3058 TA Utrecht (Netherlands); Wright, P.J. [Department of Anthropology, University of Missouri-St. Louis, St. Louis, MO 63121 (United States); Horst, J. van der; Boon, J.J. [FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam (Netherlands)
2007-03-15
The current project describes physical and chemical alterations that result from the thermal exposure of sunflower achenes and seeds. Specifically, achenes and seeds were heated at temperatures ranging from 130 to 600 C under anoxic conditions for 60 min. Changes were measured in mass, relative percentages of C and N, internal and external morphology, molecular composition by direct temperature-resolved mass spectrometry (DTMS) under EI conditions, and the reflectance on polished specimens. The main constituents of sunflower seeds are lipids and protein, while the pericarps or hulls enclosing the seeds have a ligno-cellulosic structure. The morphology of achenes and seeds remains intact following exposure which makes the identification of the residues possible. The results of the sunflower experiments were compared to previous experiments conducted with peas and wheat grains. Up to approximately 340 C, the molecular conversion of polysaccharide and protein rich peas and wheat grains follow similar pathways, while the lignin present in sunflower achenes follows its own unique pathway, resulting in a different molecular composition. At higher temperatures the molecular composition of the three propagules becomes identical. In addition the reflectance of the three propagules is identical confirming the similarity in molecular composition. Lipids show a different behaviour compared to the other three biopolymers; from 370 C no oils are observed in the heated specimens and the DTMS-EI measurements show no lipid markers. Apart from evaporation of the triacylglycerides it is suggested that steroids have a high resistance against thermal degradation and are converted into aromatic moieties. (author)
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Overcoming dormancy in seeds of cotton-silk tree
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Irinaldo Lima do Nascimento
2012-06-01
Full Text Available Cotton-silk tree Ceiba glaziovii (kuntze k. Schu belongs to family Bombacaceas and is locally known as barriguda. It is widely used in landscaping and reforestation, neverdeless seed dormancy affects reproduction in this species. The objective of this study was to evaluate the effectiveness of different methods to overcome dormancy in the germination process. Treatments included mechanical scarification with 85-grit sandpaper, chemical scarification with concentrated sulfuric acid for 5, 10, 15 and 20 minutes, physical scarification with hot water at 60°, 70°, 80°and 90° C for one minute, imbibition in distilled water for 24, 48 and 72 hours, oven heating at 65° C for 1, 2, 3 and 4 hours, and a control treatment. Each treatment included four replicates of 25 seeds, using a completely randomized experimental design, and means were compared by the Scott-Knott test at the 5% probability level. Assessed parameters included emergence percentage, emergence rate index, dry matter and length of plants. The most recommended treatments were mechanical scarification, immersion in sulfuric acid for 5, 10 and 15 minutes and immersion in distilled water for 48 hours.
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Directory of Open Access Journals (Sweden)
Yu Ping Zhou
2018-06-01
Full Text Available Seed dormancy and germination are regulated by complex mechanisms controlled by diverse hormones and environmental cues. Abscisic acid (ABA promotes seed dormancy and inhibits seed germination and post-germination growth. Calmodulin (CaM signals are involved with the inhibition of ABA during seed germination and seedling growth. In this study, we showed that Arabidopsis thaliana IQM4 could bind with calmodulin 5 (CaM5 both in vitro and in vivo, and that the interaction was the Ca2+-independent type. The IQM4 protein was localized in the chloroplast and the IQM4 gene was expressed in most tissues, especially the embryo and germinated seedlings. The T-DNA insertion mutants of IQM4 exhibited the reduced primary seed dormancy and lower ABA levels compared with wild type seeds. Moreover, IQM4 plays key roles in modulating the responses to ABA, salt, and osmotic stress during seed germination and post-germination growth. T-DNA insertion mutants exhibited ABA-insensitive and salt-hypersensitive phenotypes during seed germination and post-germination growth, whereas IQM4-overexpressing lines had ABA- and osmotic-hypersensitive, and salt-insensitive phenotypes. Gene expression analyses showed that mutation of IQM4 inhibited the expression of ABA biosynthetic genes NCED6 and NCED9, and seed maturation regulators LEC1, LEC2, ABI3, and ABI5 during the silique development, as well as promoted the expression of WRKY40 and inhibited that of ABI5 in ABA-regulated seed germination. These observations suggest that IQM4 is a novel Ca2+-independent CaM-binding protein, which is positively involved with seed dormancy and germination in Arabidopsis.
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Effect of raw sunflower seeds on goat milk production in different farming systems
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L. Rapetti
2010-04-01
Full Text Available Aim of this study was to test the effect of raw sunflower seeds on goat milk production. Two farms with different farming systems (intensive and semi-intensive participated to the trial. In each farm about 60 mid-lactation Alpine goats were divided in two groups during spring-summer time. A diet containing 5-6% of sunflower seeds on DM basis was compared with a control diet in a change-over design. In the semi-intensive farm milk yield of goats fed sunflower was 3.46 kg/d compared to 3.58 kg/d of goats fed control diet, whereas in the intensive farm milk yield was 4.60 kg/d vs 4.66 kg/d. Fat content increased significantly from 2.99% to 3.23% only in the intensive farm. The research in the intensive farm investigated also milk and cheese fatty acids composition. Medium and short chain fatty acids (C8-C16 content dropped and long chain fatty acids content increased when sunflower was added. In conclusion raw sunflower seed inclusion in dairy goat diets can be useful, in order to limit the inversion of fat and protein percentages in milk.
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Seglias, Alexandra E; Williams, Evelyn; Bilge, Arman; Kramer, Andrea T
2018-01-01
For many species and seed sources used in restoration activities, specific seed germination requirements are often unknown. Because seed dormancy and germination traits can be constrained by phylogenetic history, related species are often assumed to have similar traits. However, significant variation in these traits is also present within species as a result of adaptation to local climatic conditions. A growing number of studies have attempted to disentangle how phylogeny and climate influence seed dormancy and germination traits, but they have focused primarily on species-level effects, ignoring potential population-level variation. We examined the relationships between phylogeny, climate, and seed dormancy and germination traits for 24 populations of eight native, restoration-relevant forb species found in a wide range of climatic conditions in the Southwest United States. The seeds were exposed to eight temperature and stratification length regimes designed to mimic regional climatic conditions. Phylogenetic relatedness, overall climatic conditions, and temperature conditions at the site were all significantly correlated with final germination response, with significant among-population variation in germination response across incubation treatments for seven of our eight study species. Notably, germination during stratification was significantly predicted by precipitation seasonality and differed significantly among populations for seven species. While previous studies have not examined germination during stratification as a potential trait influencing overall germination response, our results suggest that this trait should be included in germination studies as well as seed sourcing decisions. Results of this study deepen our understanding of the relationships between source climate, species identity, and germination, leading to improved seed sourcing decisions for restorations.
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Chang, Ermei; Deng, Nan; Zhang, Jin; Liu, Jianfeng; Chen, Lanzhen; Zhao, Xiulian; Abbas, M; Jiang, Zeping; Shi, Shengqing
2018-03-21
Gnetum parvifolium is a rich source of materials for traditional medicines, food, and oil, but little is known about the mechanism underlying its seed dormancy and germination. In this study, we analyzed the proteome-level changes in its seeds during germination using isobaric tags for relative and absolute quantitation. In total, 1,040 differentially expressed proteins were identified, and cluster analysis revealed the distinct time points during which signal transduction and oxidation-reduction activity changed. Gene Ontology analysis showed that "carbohydrate metabolic process" and "response to oxidative stress" were the main enriched terms. Proteins associated with starch degradation and antioxidant enzymes were important for dormancy-release, while proteins associated with energy metabolism and protein synthesis were up-regulated during germination. Moreover, protein-interaction networks were mainly associated with heat-shock proteins. Furthermore, in accord with changes in the energy metabolism- and antioxidant-related proteins, indole-3-acetic acid, Peroxidase, and soluble sugar content increased, and the starch content decreased in almost all six stages of dormancy and germination analyzed (S1-S6). The activity of superoxide dismutase, abscisic acid, and malondialdehyde content increased in the dormancy stages (S1-S3) and then decreased in the germination stages (S4-S6). Our results provide new insights into G. parvifolium seed dormancy and germination at the proteome and physiological levels, with implications for improving seed propagation.
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Miatton, Emma
2012-01-01
Seed dormancy is defined as the incapacity of a viable seed to germinate under favourable conditions. It is established during seed maturation and reaches high levels in mature dry seeds. Dormancy is a complex adaptive trait that assures germination at proper time of the year at the onset of the favourable growing season. This trait is regulated by hormonal and environmental cues such as temperature and light. In Arabidopsis thaliana dormancy can be released by imbibing seeds at cold temperat...
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Analysis the parameters of seed quality in ns sunflower hybrid after processing in gravity separator
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Jokić Goran
2016-01-01
Full Text Available This paper analyzed the processed seed of five sunflower hybrid seed developed at the Institute of Field and Vegetable Crops in Novi Sad before and after processing in gravity separator. The cultivars were Pegaz, Duško, NS Fantazija, Sumo 1 PR and NS Oskar. The analysis was conducted on seed lots processed in 2015 and involved the following parameters: seed purity percentage, 1.000-seed weight, germination energy, germination, seed moisture, number of sclerotinia per 1.000. The results showed that all the parameters of seed quality of sunflower hybrids were better after processing seeds in the gravity separator.
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Model-free pyrolysis kinetics of sunflower seed and its de-oiled cake
International Nuclear Information System (INIS)
Özsin, Gamzenur; Kilic, Murat; Pütün, Ersan; Pütün, Ayşe E.
2015-01-01
Sunflower seed wastes from oil production are a potential biomass source for bio- energy production due to extensive and excessive oil production from sunflower seeds. Considering global energy requirement, pyrolysis seems a promising route for utilisation of such industrial biomass wastes. To develop, scale-up and operate pyrolysis plants efficiently, a fundamental understanding of pyrolysis behaviour and kinetics is essential. In this study, sunflower seeds and their waste cakes after extraction were evaluated as a potential biomass feedstock in pyrolysis process. In order to enlighten pyrolytic degradation behaviours, samples were pyrolysed under dynamic conditions from room temperature to 1000 °C using multiple heating rates. The main degradation regimes of the structures were characterized by high weight loss rates. Reaction kinetics was investigated with respect to conversion degree. It is anticipated that this study will be beneficial in optimizing the thermochemical processes, which may be utilize industrial biomass wastes. (full text)
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Directory of Open Access Journals (Sweden)
Kai Shu
2013-06-01
Full Text Available Seed dormancy is an important economic trait for agricultural production. Abscisic acid (ABA and Gibberellins (GA are the primary factors that regulate the transition from dormancy to germination, and they regulate this process antagonistically. The detailed regulatory mechanism involving crosstalk between ABA and GA, which underlies seed dormancy, requires further elucidation. Here, we report that ABI4 positively regulates primary seed dormancy, while negatively regulating cotyledon greening, by mediating the biogenesis of ABA and GA. Seeds of the Arabidopsis abi4 mutant that were subjected to short-term storage (one or two weeks germinated significantly more quickly than Wild-Type (WT, and abi4 cotyledons greened markedly more quickly than WT, while the rates of germination and greening were comparable when the seeds were subjected to longer-term storage (six months. The ABA content of dry abi4 seeds was remarkably lower than that of WT, but the amounts were comparable after stratification. Consistently, the GA level of abi4 seeds was increased compared to WT. Further analysis showed that abi4 was resistant to treatment with paclobutrazol (PAC, a GA biosynthesis inhibitor, during germination, while OE-ABI4 was sensitive to PAC, and exogenous GA rescued the delayed germination phenotype of OE-ABI4. Analysis by qRT-PCR showed that the expression of genes involved in ABA and GA metabolism in dry and germinating seeds corresponded to hormonal measurements. Moreover, chromatin immunoprecipitation qPCR (ChIP-qPCR and transient expression analysis showed that ABI4 repressed CYP707A1 and CYP707A2 expression by directly binding to those promoters, and the ABI4 binding elements are essential for this repression. Accordingly, further genetic analysis showed that abi4 recovered the delayed germination phenotype of cyp707a1 and cyp707a2 and further, rescued the non-germinating phenotype of ga1-t. Taken together, this study suggests that ABI4 is a key
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Gholam reza doraki
2017-01-01
Full Text Available Introduction: Stalked Bur Grass (Tragus racemosus L. is an angiosperm annual plant with C4 photosynthesis pathway and stolon. It grows in hot and dry summers. This plant spreaded throughout the world from hot regions of Africa. It is regularly seen in barren lands or in between the generations with sequential initial stages with light-texture soils. Seed dormancy is in fact a physiological phenomenon which is observed in the seeds of most crops, pasture plants, medicinal herbs and weeds. Dormancy allows the plant to guarantee its germination and survival for long years and to survive through adverse environmental conditions through its spatial and temporal spread. Materials and Methods: In order to evaluation dormancy break of Tragus racemosus L. seeds, an experiment was carried out based a Randomized Complete Block Design with four replications in research laboratory of Department of Agriculture, Birjand University during 2013. The initial experiments showed that the seeds of Stalked Bur Grass had initial dormancy and were unable to germinate at normal conditions, so that less than 5% of the seeds germinated. The studied treatments for breaking seeds dormancy included control (seeds disinfection by distilled water, wet chilling at 4°C for 1, 2, 3 and 4 weeds, treatment with H2SO4 at 97% for 20, 40, 60 and 80 seconds, treatment with KNO3 at 0.2, 0.4, 0.6 and 0.8% for 24 hours and treatment with Gibberellic acid (GA3 at 50, 100, 200 and 400 ppm. In this study, 25 seeds of Stalked Bur Grass were uniformly placed in petri dishes with the diameters of 9 cm on Watmann filter papers and were applied with 5 mL distilled water. The number of germinated seeds was counted on a daily basis for 21 days. In the end, germination percentage and rate was determined. Results and Discussion: The results revealed that the effect of all studied levels of all treatments were significant on germination percentage and rate. The highest germination percentage (76% was
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Expression Analysis of the MdCIbHLH1 Gene in Apple Flower Buds and Seeds in the Process of Dormancy
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Yiran Ren
2016-03-01
Full Text Available A bHLH transcription factor that is induced by low temperature was found in apple (Malus × domestica Borkh.. To understand the sequence characteristics of the gene, bioinformatics analysis was performed. Furthermore, gene expression patterns of the laminated apple seeds and lateral flower buds were analyzed during the period of dormancy release with semi-quantitative RT-PCR. Based on secondary structure predictions, the results showed that the MdCIbHLH1 protein structure mainly included α-helix and random coil, while β-sheet and extended strand content was less. Semi-quantitative RT-PCR analysis showed that the expression patterns of MdCIbHLH1 were similar in laminated apple seeds and lateral flower buds during the period of dormancy release. Before dormancy release, expression levels of MdCIbHLH1 were high and gradually decreased during the period of dormancy release. These results indicated that MdCIbHLH1 might play an important role during dormancy release in apple seeds and apple buds.
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Mature forms of the major seed storage albumins in sunflower: A mass spectrometric approach.
Franke, Bastian; Colgrave, Michelle L; Mylne, Joshua S; Rosengren, K Johan
2016-09-16
Seed storage albumins are abundant, water-soluble proteins that are degraded to provide critical nutrients for the germinating seedling. It has been established that the sunflower albumins encoded by SEED STORAGE ALBUMIN 2 (SESA2), SESA20 and SESA3 are the major components of the albumin-rich fraction of the common sunflower Helianthus annuus. To determine the structure of sunflowers most important albumins we performed a detailed chromatographic and mass spectrometric characterization to assess what post-translational processing they receive prior to deposition in the protein storage vacuole. We found that SESA2 and SESA20 each encode two albumins. The first of the two SESA2 albumins (SESA2-1) exists as a monomer of 116 or 117 residues, differing by a threonine at the C-terminus. The second of the two SESA2 albumins (SESA2-2) is a monomer of 128 residues. SESA20 encodes the albumin SESA20-2, which is a 127-residue monomer, whereas SESA20-1 was not abundant enough to be structurally described. SESA3, which has been partly characterized previously, was found in several forms with methylation of its asparagine residues. In contrast to other dicot albumins, which are generally matured into a heterodimer, all the dominant mature sunflower albumins SESA2, SESA20-2, SESA3 and its post-translationally modified analogue SESA3-a are monomeric. Sunflower plants have been bred to thrive in various climate zones making them favored crops to meet the growing worldwide demand by humans for protein. The abundance of seed storage proteins makes them an important source of protein for animal and human nutrition. This study explores the structures of the dominant sunflower napin-type seed storage albumins to understand what structures evolution has favored in the most abundant proteins in sunflower seed. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.
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QTL analysis of seed dormancy in Arabidopsis using recombinant inbred lines and MQM mapping
Schaar, Wybe van der; Alonso-Blanco, Carlos; Léon-Kloosterziel, Karen M.; Jansen, Ritsert C.; Ooijen, Johan W. van; Koornneef, Maarten
1997-01-01
The genetic differences for seed germination between two commonly used Arabidopsis thaliana ecotypes Ler and Col, both showing a low level of seed dormancy, were investigated. The analysis was performed with 98 recombinant inbred lines (RILs) derived from the cross between the two ecotypes, and
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Analysis of seed quality in NS sunflower hybrid seed processed between 2010 and 2014
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Jokić Goran
2015-01-01
Full Text Available This paper analyzed the processed seed of five sunflower hybrid seed developed at the Institute of Field and Vegetable Crops in Novi Sad. The cultivars were Rimi PR, Duško, NS Dukat, Sumo 1 PR and Sremac. The analysis was conducted on seed lots processed between 2010 and 2014 and involved the following parameters: seed purity percentage, 1000-seed weight, germination energy, germination, seed moisture, number of weed seeds per 1000 grams of seed. The results of the study produced the following average values: seed purity - 99.72%, 1000-seed weight - 67.59g, germination energy - 88.2%, germination - 91.8%, seed moisture - 8.3%. There were not found weeds seeds as well as pathogens on the seed samples, these values are all within the legally prescribed limits.
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Baltazar, A L; de Mattos, G M; Ropelli, B M; Firetti, Smg; Castilho, C; Pugliesi, G; Maldonado, Mbc; Binelli, M; Silva, Jof; Lupatini, G C; Lafuente, B S; Membrive, Cmb
2018-06-01
Supplementation with compounds rich in linoleic acid, including sunflower seed supplementation, promotes increase in conception rates in cows. We aimed to evaluate whether the sunflower seed (linoleic acid source) supplementation in beef donor females alters the plasma concentrations of cholesterol, triglycerides, HDL and LDL, increases the number and quality of oocytes, increases the cleavage rates and determines an improvement in number and quality of in vitro produced blastocysts. Thus, Nelore females were divided into two groups of 15 animals to receive supplementation with or without sunflower seed for 57 days. Females underwent follicular aspiration and the oocytes were subjected to in vitro embryo production. There was no difference (p > .1) between control group and group supplemented with sunflower seed on the number of displayed follicles; number of aspired oocytes; recovery rate; cleavage rate; number of embryos; number of blastocysts; embryos number of grades I and II; plasma concentrations of total cholesterol, triglycerides; HDL and LDL. Therefore, sunflower seed supplementation in oocyte donors did not increase the number and quality of oocytes, cleavage rates and the number and quality of blastocysts produced in vitro. © 2018 Blackwell Verlag GmbH.
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Wang, Jia; Baskin, Jerry M; Baskin, Carol C; Liu, Guofang; Yang, Xuejun; Huang, Zhenying
2017-06-01
Cistanche deserticola is a holoparasitic plant with high medicinal value that reproduces only by seeds. However, the requirements for seed dormancy break and germination of this species remain unclear. The freshly matured dust-like seeds consist of a water-permeable seed coat and an undifferentiated oval-shaped embryo embedded in endosperm. No fresh seeds germinated in water or a 10 -5 M fluridone solution at any incubation temperature within 60 days. Length of embryos in seeds incubated in warm- and cold-started stratification sequences had increased 10.4 and 11.7% after 50 and 40 weeks, respectively. After 6 months, length of embryos in seeds stratified at 5 °C had increased by 12%. Germination of fresh seeds and of seeds stratified at 5 °C for 6 months and then incubated in mixed fluridone/gibberellic acid 3 (GA 3 ) solutions at 30/20 °C germinated to only 2.6 and 11.7%, respectively. Embryos of fresh seeds and of cold-stratified seeds had increased 29.4 and 15.8% in length, respectively, at the time of germination, but they never differentiated into organs. The highest germination (54.4%) was for seeds incubated in a 10 -5 M solution of fluridone in darkness in spring that had overwinter on the soil surface in the natural habitat. Our study indicates that breaking of physiological dormancy (PD) occurs first and then the embryo grows to a critical length (0.44 mm) without differentiation into organs prior to seed germination. Seeds for which PD had been broken were induced to germinate by fluridone and GA 3 at high temperature. Taken together, these results suggest that C. deserticola seeds have a specialized kind of morphophysiological dormancy. This study reveals possible ways to release seed dormancy that will be useful in propagating this medicinal species. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Ali-Rachedi, Sonia; Bouinot, Denise; Wagner, Marie-Hélène; Bonnet, Magda; Sotta, Bruno; Grappin, Philippe; Jullien, Marc
2004-07-01
Mature seeds of the Cape Verde Islands (Cvi) ecotype of Arabidopsis thaliana (L.) Heynh. show a very marked dormancy. Dormant (D) seeds completely fail to germinate in conditions that are favourable for germination whereas non-dormant (ND) seeds germinate easily. Cvi seed dormancy is alleviated by after-ripening, stratification, and also by nitrate or fluridone treatment. Addition of gibberellins to D seeds does not suppress dormancy efficiently, suggesting that gibberellins are not directly involved in the breaking of dormancy. Dormancy expression of Cvi seeds is strongly dependent on temperature: D seeds do not germinate at warm temperatures (20-27 degrees C) but do so easily at a low temperature (13 degrees C) or when a fluridone treatment is given to D seeds sown at high temperature. To investigate the role of abscisic acid (ABA) in dormancy release and maintenance, we measured the ABA content in both ND and D seeds imbibed using various dormancy-breaking conditions. It was found that dry D seeds contained higher amounts of ABA than dry ND after-ripened seeds. During early imbibition in standard conditions, there was a decrease in ABA content in both seeds, the rate of which was slower in D seeds. Three days after sowing, the ABA content in D seeds increased specifically and then remained at a high level. When imbibed with fluridone, nitrate or stratified, the ABA content of D seeds decreased and reached a level very near to that of ND seeds. In contrast, gibberellic acid (GA3) treatment caused a transient increase in ABA content. When D seeds were sown at low optimal temperature their ABA content also decreased to the level observed in ND seeds. The present study indicates that Cvi D and ND seeds can be easily distinguished by their ability to synthesize ABA following imbibition. Treatments used here to break dormancy reduced the ABA level in imbibed D seeds to the level observed in ND seeds, with the exception of GA3 treatment, which was active in promoting
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WAYAN SUENA
2012-11-01
Full Text Available The experiment aimed to know the effect of length of soaked time in sulfuric acid (H2SO4 solution to the dormancy breaking upon the oil palm seeds. The experiment show that soaking seeds for 12 and 10 minutes in the acid solution resulted dormancy breaking were reached after 61.3 days, while soaking seed for 2 minutes in the same solution breaking of dormancy was reached after 73.5 days. By soaked oil palm seeds in sulfuric acid solution gave highest germination percentage (80%, peak value of germination was 0.77%/day, by an average of 0.73%/day. So that, by soaked oil palm seed in sulfuric acid solution for 12 minutes was able to increase vigor, viability, rate of germination and growth uniformity.
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Control of quality and silo storage of sunflower seeds using near infrared technology
Energy Technology Data Exchange (ETDEWEB)
Gonzalez-Martin, I.; Vilaescusa-Garcia, V.; Lopez-Gonzalez, F.; Oiz-Jimenez, C.; Lobos-Ortega, I. A.; Gordillo, B.; Hernandez-Hierro, J. M.
2013-05-01
This work assesses the application of near infrared spectroscopy technology for the quality control of sunflower seeds direct from farmers and from a storage silo. The results show that the analytical method employing near infrared spectroscopy can be used as a rapid and non-destructive tool for the determination of moisture, fat and high/low oleic acid contents in samples of sunflower seeds. The ranges obtained were comparable to those reported for classic chemical methods, and were between 4.6-21.4% for moisture; 38.4-49.6% for fat, and 60.0-93.1% for oleic acid expressed as percentage of total fatty acids. A stepwise discriminant analysis was performed to determine the most useful wavelengths for classifying sunflower seeds in terms of their (high/low) oleic acid composition. The discriminant model allows the acid contents, with a prediction rate of 90.5% for internal validation and of 89.4% for cross-validation. (Author) 23 refs.
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Control of quality and silo storage of sunflower seeds using near infrared technology
International Nuclear Information System (INIS)
Gonzalez-Martin, I.; Vilaescusa-Garcia, V.; Lopez-Gonzalez, F.; Oiz-Jimenez, C.; Lobos-Ortega, I. A.; Gordillo, B.; Hernandez-Hierro, J. M.
2013-01-01
This work assesses the application of near infrared spectroscopy technology for the quality control of sunflower seeds direct from farmers and from a storage silo. The results show that the analytical method employing near infrared spectroscopy can be used as a rapid and non-destructive tool for the determination of moisture, fat and high/low oleic acid contents in samples of sunflower seeds. The ranges obtained were comparable to those reported for classic chemical methods, and were between 4.6-21.4% for moisture; 38.4-49.6% for fat, and 60.0-93.1% for oleic acid expressed as percentage of total fatty acids. A stepwise discriminant analysis was performed to determine the most useful wavelengths for classifying sunflower seeds in terms of their (high/low) oleic acid composition. The discriminant model allows the acid contents, with a prediction rate of 90.5% for internal validation and of 89.4% for cross-validation. (Author) 23 refs.
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NATURAL ACID IN OVERCOMING PINHA SEED DORMANCY (ANNONA SQUAMOSA L.
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A. R. Santos
2018-02-01
Full Text Available The production of good quality seedlings becomes essential strategy for those who wish to become production that is more competitive. To induce dormancy breaking and germination and emergence of these, the imbibing of natural acid in seeds can be an alternative for the optimization of this process. The aim of this study is to evaluate the dormancy breaking in Anonna seeds squamosa immersed in different natural acid in times through the lemon juice Rangpur (Citrus limonia Osbeck. This work is being conducted in Biotecnogia laboratory greenhouse at the Federal Institute Goiano campus Urutaí where the seeds were soaked in lemon juice Rangpur (C. limonia in five different times, each time constituting a treatment: seeds without soaking in lemon groove variety Cravo '(T1; soaked for 8 hours (T2; soaked for 16 hours (T3; soaked for 24 hours (T4; soaked for 32 hours (T5. The seeds were sown in plastic boxes with dimensions 40 x 27 x 10 cm, containing washed sand substrate, 2 cm deep in spacing of 2 x 2 cm. The germination percentage data were determined up to 45 days after sowing (DAS, and survival to 73 (DAS. After 73 DAS were evaluated after 73 days of sowing, they were evaluated; germination and survival; emergence speed index (EVI; total length of seedlings; shoot length of seedlings and radicle length (cm; Stem diameter (mm; pair of leaf number (MPN; total fresh mass changes (MFT; dry matter of shoot and radicle (g. There was not statistical diseases among treatments. T4 treatment in comparison to others on the numerical difference CTM, NPF, DC and CPA.
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Results of presowing helium-neon-laser irradiation of sunflower seeds
International Nuclear Information System (INIS)
Tsvetanova, K.
1989-01-01
In the period of 1983-1985 under non-irrigation, on calcareous chernozem a trial was carried out with the Start hybrid through single-, double-and triple irradiation of the seeds being stored for 1.8 and 16 days prior to sowing. It is found that the presowing helium-neon-laser irradiation of the sunflower seeds of the Start hybrid exerts a negative effect on the seed yield. Laser use does not stimulate the following: emerged seeds and percentage of the plants being in blossom in the beginning of the phase and after 7 days, seed moisture in harvesting and oil content in them
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Regulation of Picea abies seed dormancy by red and far-red light at various moisture contents
Energy Technology Data Exchange (ETDEWEB)
Leinonen, K.; Chantal, M. de [Helsinki Univ. (Finland). Dept. of Forest Ecology
1998-04-01
The effects of red (R), far-red (FR) and R+FR light on Norway spruce seed dormancy were studied at five different moisture contents (MC) between 5 and 20%. The degree of dormancy was studied by germinating seeds over a wide range of temperatures in the dark. The non-irradiated control seeds were shallowly dormant, only a proportion of them germinated and within a limited temperature range. Red light progressively stimulated germination between 5 and 17% MC, but this effect was reversed if a FR treatment followed, although all germination could not be inhibited by one FR pulse. Far-red light had a slightly stimulating effect at 19% MC. To generate seeds able to germinate over a wide range of temperatures in darkness, an artificial light pretreatment should be given to seeds at MC above 17% in order to receive maximum response 24 refs, 2 figs, 1 tab
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Seed dormancy alleviation of grewia tenax (forssk.): a wild fruit tree species of pakistan
International Nuclear Information System (INIS)
Sohail, M.; Saied, A.S.
2015-01-01
Grewia tenax (Forssk.) Fiori is a fruit shrub and grows wild in arid and semi-arid tropics of Asia and Africa. The species is highly valuable for the rural populations because of its edible fruit and fodder for livestock. Species has immense potential for re-vegetation of degraded lands, as it has ability to withstand soil salinity and drought. Wild stands of the species are sparse which is supposed to have some kind of seed dormancy. Seeds of G. tenax were subjected to different combinations of heat and cold seed stratification treatments in two consecutive experiments. A positive correlation (r2 = 0.97) was observed between total emergence and weeks of seed exposure to constant dry heat at 40 degree C from 0 to 4 weeks. Maximum germination (70%) was achieved, when seeds were exposed to dry heat at 40 degree C for 4 weeks as compared to control (20%). Seeds exposed to constant heat for 4 weeks also took only 4 and 5 days to reach 1st and 50% emergence, respectively as compared to untreated seeds, which took 10 and 14 days to reach 1st and 50% emergence, respectively. Moreover, emergence spread lasted only 4 days as compared to untreated seeds with 21 days. Our results indicate that seeds of G. tenax possess a limited physiological dormancy which can be overcome by heat stratification. (author)
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Seed dormancy and germination of Halophila ovalis mediated by simulated seasonal temperature changes
Statton, John; Sellers, Robert; Dixon, Kingsley W.; Kilminster, Kieryn; Merritt, David J.; Kendrick, Gary A.
2017-11-01
The seagrass, Halophila ovalis plays an important ecological and sediment stability role in estuarine systems in Australia with the species in decline in many sites. Halophila ovalis is a facultative annual, relying mainly on recruitment from the sediment seed bank for the annual regeneration of meadows. Despite this, there is little understanding of seed dormancy releasing mechanisms and germination cues. Using H. ovalis seed from the warm temperate Swan River Estuary in Western Australia, the germination ecology of H. ovalis was investigated by simulating the natural seasonal variation in water temperatures. The proportion of germinating seeds was found to be significantly different among temperature treatments (p < 0.001). The treatment with the longest period of cold exposure at 15 °C followed by an increase in temperature to 20-25 °C (i.e. cold stratification) had the highest final mean germination of 32% and the fastest germination rate. Seeds exposed to constant mean winter temperatures of 15 °C had the slowest germination rate with less than two seeds germinating over 118 days. Thus temperature is a key germination cue for H. ovalis seeds and these data infer that cold stratification is an important dormancy releasing mechanism. This finding has implications for recruitment in facultative annual species like H. ovalis under global warming since the trend for increasing water temperatures in the region may limit seed-based recruitment in the future.
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Differentially expressed genes associated with dormancy or germination of Arabidopsis thaliana seeds
Toorop, P.E.; Barroco, R.M.; Engler, G.; Groot, S.P.C.; Hilhorst, H.W.M.
2005-01-01
Differential display analysis using dormant and non-dormant Arabidopsis thaliana (L.) Heynh seeds resulted in a set of genes that were associated with either dormancy or germination. Expression of the germination-associated genes AtRPL36B and AtRPL27B, encoding two ribosomal proteins, was
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Directory of Open Access Journals (Sweden)
Francilaine Eloise De Marchi
2013-09-01
Full Text Available The objective of this study was to evaluate intake, in vitro and apparent digestibility and ruminal parameters of Holstein cows that were confined and fed corn silage and concentrate containing: ground sunflower seeds (GS; ground sunflower seeds treated with 5% lignosulfonate (GSL; pelleted sunflower seeds (PS; or ground and pelleted sunflower seeds treated with lignosulfonate (PSL. Four lactating cows with 130±28 days of lactation and body weights of 569±63 kg were used. These animals were distributed in a Latin square design with four diets and four periods of 21 days each. There were no differences in the intakes (% body weight of dry matter (DM, organic matter (OM, mineral matter (MM, crude protein (CP, neutral detergent fiber (NDF or acid detergent fiber (ADF. The apparent digestibility of DM, OM, CP, EE, NDF, ADF and NFC were similar for all the diets, with a tendency towards decreased CP digestibility for all the pelleted diets (65.79% compared with the non-pelleted diets (69.66%. A negative effect of lignosulfonate was observed for the in vitro digestibility (IVD of DM, and a negative tendency was observed for the IVD of OM. Pelleting decreased the concentration of acetic acid (55.95 × 58.82 mM in rumen fluid. There was no effect of diet on pH (6.17 or ammonia nitrogen concentration (18.19 mg/dL. Pelleting and lignosulfonate do not promote the protective effect of sunflower seed nutrients as expected, and it may be more feasible to provide ground sunflower seed.
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Research on Overcoming the Dormancy Problem of Molekhia (Corchorus olitorius L. Seeds
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Burcu TUNCER
2017-10-01
Full Text Available In this study, the effect of different seed applications on germination and emergence in order to break dormancy of the seeds of molekhia (Corchorus olitorius L. which is used as fiber, medicinal plant and consumed as a vegetable, was investigated. For this purpose, sterilized seeds were exposed to boiling water (95 ºC; 10 and 30 seconds, 1, 5 and 10 minutes, hot water (80 ºC; 5, 10, 15 and 20 minutes, sulfuric acid (98%; 5, 10, 15, 20, 25 and 30 minutes and pre-cooling (4 ºC; 2, 3 and 4 days treatments. The experiments were carried out according to randomized blocks trial design with 4 replications and 50 seeds per replicate. According to results obtained, germination rate 0.00-97.00%, average germination time 0.00-3.98 days, germination index 0.00-46.89, emergence rate 0.00-82.00%, average emergence time 0.00-7.52 days, emergence index 0.00-18.70, hypocotyl length 0.00-1.79 cm and radicle length values varied between 0.00 and 4.28 cm. The most successful treatments in terms of germination and emergence parameters were pre-chilling, sulfuric acid (for 5 and 10 minutes and boiled water (at 95 ºC for 10 seconds applications. As a result of the study, in order to remove the dormancy from the Corchorus olitorius L. seeds, treatment of the seeds with pre-cooling (4 ºC for 2 days in a humid environment before sowing would be easily practiced.
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Comparison of germination and seed vigor of sunflower in two contaminated soils of different texture
Zhao, Xin; Han, Jaemaro; Lee, Jong Keun; Kim, Jae Young
2014-05-01
Phytoremediation as an emerging low-cost and ecologically friendly alternative to the conventional soil remediation technologies has gained a great deal of attention and into lots of research. As a kind of the methods that use of green plants to remediate heavy metals contaminated soils, the early growth status of plant seeds in the contaminated environmental directly affects the effect of phytoremediation. Germination test in the water (aqueous solution of heavy metal) is generally used for assessing heavy metal phytotoxicity and possibility of plant growth, but there is a limit. Because soil is commonly main target of phytoremediation, not the water. The bioavailability of heavy metals in the soil also depends on the texture. So soil texture is an important factor of phytoremediation effect. Sunflower is the representative species which have good tolerance to various heavy metals; furthermore, the seeds of sunflower can be used as the raw-material for producing bio-diesel. The objectives of this research were to investigate germination rate of sunflowers in various heavy metal contaminated soils and to compare the seedling vigor index (SVI) of sunflower in two contaminated soils of different texture. Sunflower (Helianthusannuus L.) seeds were obtained from a commercial market. In order to prove the soil texture effect on heavy metal contaminated soil, germination tests in soil were conducted with two different types of soil texture (i.e., loam soil and sandy loam soil) classified by soil textural triangle (defined by USDA) including representative soil texture of Korea. Germination tests in soil were conducted using KS I ISO 11260-1 (2005) for reference that sunflower seeds were incubated for 7 days in dark at 25 ± 1 Celsius degree. The target heavy metals are Nickel (Ni) and Zinc (Zn). The Ni and Zn concentrations were 0, 10, 50, 100, 200, 300, 500 mg-Ni/kg-dry soil, and 0, 10, 50, 100, 300, 500, 900 mg-Zn/kg-dry soil, respectively. After germination test for 7
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Role of protein and mRNA oxidation in seed dormancy and germination
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hayat eel-maarouf-bouteau
2013-04-01
Full Text Available Reactive oxygen species (ROS are key players in the regulation of seed germination and dormancy. Although their regulated accumulation is a prerequisite for germination, the cellular basis of their action remains unknown, but very challenging to elucidate due to the lack of specificity of these compounds that can potentially react with all biomolecules. Among these, nucleic acids and proteins are very prone to oxidative damage. RNA is highly sensitive to oxidation because of its single-stranded structure and the absence of a repair system. Oxidation of mRNAs induces their decay through processing bodies or results in the synthesis of aberrant proteins through altered translation. Depending on the oxidized amino acid, ROS damage of proteins can be irreversible (i.e. carbonylation thus triggering the degradation of the oxidized proteins by the cytosolic 20S proteasome or can be reversed through the action of thioredoxins, peroxiredoxins or glutaredoxins (cysteine oxidation or by methionine sulfoxide reductase (methionine oxidation. Seed dormancy alleviation in the dry state, referred to as after-ripening, requires both selective mRNA oxidation and protein carbonylation. Similarly, seed imbibition of non-dormant seeds is associated with targeted oxidation of a subset of proteins. Altogether, these specific features testify that such oxidative modifications play important role in commitment of the cellular functioning toward germination completion.
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Fafiolu, A O; Oduguwa, O O; Jegede, A V; Tukura, C C; Olarotimi, I D; Teniola, A A; Alabi, J O
2015-08-01
Six hundred and forty one-day-old layer chicks were used to investigate the effect of replacing soybean meal with undecorticated sunflower seed meal protein for protein at 0, 25, 50, and 75% levels. Diets were without enzyme supplementation or with enzyme supplementation with four replications of twenty birds. Growth performance and nutrient utilization were determined. Proximate composition of the undecorticated sunflower seed meal used revealed that undecorticated sunflower seed meal contained 925.9, 204.5, 336.2, 215.1, 52.0 and 192.2g/kg dry matter, crude protein, ether extract, crude fibre, ash and soluble carbohydrates, respectively. Results showed that the final weight of 484.4 g/bird was obtained for birds on 75% undecorticated sunflower seed meal diet, while the lowest value of 472.2g/bird was obtained for birds on 25% undecorticated sunflower seed meal diet. Weight gain per bird per day was not significantly (P > 0.05) affected as the level of undecorticated sunflower seed meal increased in the diets. Feed intake per bird per day increased (P meal inclusion in the diet. However, enzyme supplementation of the diets showed marked (P meal inclusion in the diet while crude protein digestibility progressively reduced (P meal increased in the diet. Ash digestibility values were, however, increased (P meal increased in the diets. Birds on enzyme-supplemented diets consistently showed superior (P meal in the diets of layer chicks showed a similar body weight gain/bird/day with the control. Undecorticated sunflower seed meal used in this study is a good source of crude protein, ether extract, and amino acids and had the potential to serve as feeding stuffs as replacement for soybeans. The nutritive value of undecorticated sunflower seed meal was improved for layer chicks with exogenous enzyme supplementation. © 2015 Poultry Science Association Inc.
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Dormancy overcoming, temperatures and substrates on germination of Mimosa tenuiflora Willd seeds
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Clarisse Pereira Benedito
2017-03-01
Full Text Available Mimosa tenuiflora Willd., popularly known as jurema-preta, is an arboreal species of great importance for the brazilian Northeast due to its uses as a medicinal plant and in the restoration of degraded soils. No information is available in the Rules for Seed Analysis and the Instructions for Seed Analysis of Forest Species regarding ideal conditions for of this species. Thus, this study aimed at evaluating the influence of pre-germination treatments, in addition to verifying the germination performance at different temperatures and in different substrates. In both experiments, four replicates of 25 seeds were used for each treatment. In experiment I, seeds were submitted to the following methods for overcoming dormancy: witness - Intact seeds (T1 immersion in water at 100 °C for 1 (T2, 2 (T3, 3 (T4, 4 (T5, 5 (T6 and 6 min (T7, immersion in concentrated sulfuric acid for 1 (T8, 4 (T9, 7 (T10, 10 (T11 and 13 min (T12, scarification on sandpaper n° 80 (T13 and lopping in the region opposite the micropyle (T14. In experiment II, seed germination was evaluated in four types of substrates: between sand, paper on, paper roll and between vermiculite and at six different temperatures: 20, 25, 30, 35, 40 °C and alternating between 20 and 30 °C. Immersion in hot water for 1, 2, 3, 4, 5 and 6 min, sulfuric acid treatment for 10 and 13 min, sand paper and lopping were the most appropriate treatments to overcome seed dormancy. The seed germination of M. Tenuiflora should be carried out at 25 °C on paper roll substrate.
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Lu, Juan J; Tan, Dun Y; Baskin, Carol C; Baskin, Jerry M
2016-04-27
The maternal environment can influence the intensity of seed dormancy and thus seasonal germination timing and post-germination life history traits. We tested the hypotheses that germination season influences phenotypic expression of post-germination life history traits in the cold desert annual Isatis violascens and that plants from autumn- and spring-germinating seeds produce different proportions of seeds with nondeep and intermediate physiological dormancy (PD). Seeds were sown in summer and flexibility in various life history traits determined for plants that germinated in autumn and in spring. A higher percentage of spring- than of autumn-germinating plants survived the seedling stage, and all surviving plants reproduced. Number of silicles increased with plant size (autumn- > spring-germinating plants), whereas percent dry mass allocated to reproduction was higher in spring- than in autumn-germinating plants. Autumn-germinating plants produced proportionally more seeds with intermediate PD than spring-germinating plants, while spring-germinating plants produced proportionally more seeds with nondeep PD than autumn-germinating plants. Flexibility throughout the life history and transgenerational plasticity in seed dormancy are adaptations of I. violascens to its desert habitat. Our study is the first to demonstrate that autumn- and spring-germinating plants in a species population differ in proportion of seeds produced with different levels of PD.
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Seed yield and protein content in sunflower depending on stand density
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Balalić Igor M.
2016-01-01
Full Text Available The aim of this research was to investigate the effect of stand density on seed yield and protein content in sunflower hybrids. The field experiment was carried out at Rimski Šančevi location. Six NS sunflower hybrids were examined. Five hybrids are confectionery (NS Goliat, NS Slatki, NS Gricko, Vranac and Cepko, and one is used for bird food (NS-H-6485. The trial was arranged as randomized complete block design (RCBD with four replications. Sowing was done with six different densities (from 20,000 to 70,000 plants per hectare, with an increment of 10,000 plants per hectare. Analysis of variance (ANOVA showed that the effect of hybrid, stand density and hybrid × stand density interation were highly significant for seed yield and protein content. The highest seed yield, on the basis of average for all densities, was found in NS-H-6485 (4.77 t ha-1 and in NS Gricko (4.43 t ha-1. Average seed yield of hybrids significantly increased up to 50,000 plants per ha-1, when it reached the value of 4.50 t ha-1, and then decreased. Significantly higher protein content, taking into account all stand densities, showed hybrid Cepko (16.94%. Protein content, above the overall average value, was achieved in hybrid Vranac (16.11%. The highest protein content in the average for all six hybrids was at the lowest stand density (20,000 plants per ha-1, and then decreased up to higher densities. The results showed that stand density had significant effect on seed yield and protein content in sunflower hybrids. [Projekat Ministarstva nauke Republike Srbije, br. TR31025: The development of new cultivars and improving the technology of producing oil plant species for different purposes
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Spoelstra, P.
2002-01-01
Formation , germination and dormancy of seeds are important steps in the life cycle of higher plants. The seed is the generative dispersal unit, which enables plants to spread and survive through periods or seasons of less favourable conditions. In agriculture tomato is
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Aznar-Moreno, Jose A; Venegas Calerón, Mónica; Martínez-Force, Enrique; Garcés, Rafael; Mullen, Robert; Gidda, Satinder K; Salas, Joaquín J
2014-03-01
Long chain fatty acid synthetases (LACSs) activate the fatty acid chains produced by plastidial de novo biosynthesis to generate acyl-CoA derivatives, important intermediates in lipid metabolism. Oilseeds, like sunflower, accumulate high levels of triacylglycerols (TAGs) in their seeds to nourish the embryo during germination. This requires that sunflower seed endosperm supports very active glycerolipid synthesis during development. Sunflower seed plastids produce large amounts of fatty acids, which must be activated through the action of LACSs, in order to be incorporated into TAGs. We cloned two different LACS genes from developing sunflower endosperm, HaLACS1 and HaLACS2, which displayed sequence homology with Arabidopsis LACS9 and LACS8 genes, respectively. These genes were expressed at high levels in developing seeds and exhibited distinct subcellular distributions. We generated constructs in which these proteins were fused to green fluorescent protein and performed transient expression experiments in tobacco cells. The HaLACS1 protein associated with the external envelope of tobacco chloroplasts, whereas HaLACS2 was strongly bound to the endoplasmic reticulum. Finally, both proteins were overexpressed in Escherichia coli and recovered as active enzymes in the bacterial membranes. Both enzymes displayed similar substrate specificities, with a very high preference for oleic acid and weaker activity toward stearic acid. On the basis of our findings, we discuss the role of these enzymes in sunflower oil synthesis. © 2013 Scandinavian Plant Physiology Society.
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Directory of Open Access Journals (Sweden)
Kazumi Nakabayashi
2015-12-01
Full Text Available The Arabidopsis protein DELAY OF GERMINATION 1 (DOG1 is a key regulator of seed dormancy, which is a life history trait that determines the timing of seedling emergence. The amount of DOG1 protein in freshly harvested seeds determines their dormancy level. DOG1 has been identified as a major dormancy QTL and variation in DOG1 transcript levels between accessions contributes to natural variation for seed dormancy. The DOG1 gene is alternatively spliced. Alternative splicing increases the transcriptome and proteome diversity in higher eukaryotes by producing transcripts that encode for proteins with altered or lost function. It can also generate tissue specific transcripts or affect mRNA stability. Here we suggest a different role for alternative splicing of the DOG1 gene. DOG1 produces five transcript variants encoding three protein isoforms. Transgenic dog1 mutant seeds expressing single DOG1 transcript variants from the endogenous DOG1 promoter did not complement because they were non-dormant and lacked DOG1 protein. However, transgenic plants overexpressing single DOG1 variants from the 35S promoter could accumulate protein and showed complementation. Simultaneous expression of two or more DOG1 transcript variants from the endogenous DOG1 promoter also led to increased dormancy levels and accumulation of DOG1 protein. This suggests that single isoforms are functional, but require the presence of additional isoforms to prevent protein degradation. Subsequently, we found that the DOG1 protein can bind to itself and that this binding is required for DOG1 function but not for protein accumulation. Natural variation for DOG1 binding efficiency was observed among Arabidopsis accessions and contributes to variation in seed dormancy.
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Juliana Müller Freire
2015-01-01
Full Text Available Seed size and dormancy level were studied in 20 trees from two populations of Schizolobium parahybato evaluate how these characteristics occurbetween and within populations, and whether seed germination was affected by its morphometry. These two populations are located in the coastal (Paraty or mountain (Miguel Pereira regions in the state of Rio de Janeiro, Brazil. The seed morphometrictraits (length, width, thickness and weight were measured. Germination with or without seedcoatdormancy treatment (mechanical scarification wasassessedbya randomized emergence test in nursey. All morphometric traits differed significantly among individuals and between populations. The trees from the mountain region showed a larger seed size and a lower dormancy level than that of trees from the coastal region. Seed size had no effect on seed germination or seedling development. Climate influence on the determination of germination behavior is discussed based on the results.
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Keller, Susanne E; Anderson, Nathan M; Wang, Can; Burbick, Stephen J; Hildebrandt, Ian M; Gonsalves, Lauren J; Suehr, Quincy J; Farakos, Sofia M Santillana
2018-04-01
Ready-to-eat foods based on dried partially sprouted seeds have been associated with foodborne salmonellosis. Whereas research has focused on the potential for Salmonella initially present in or on seeds to grow and survive during fresh sprout production, little is known about the potential for growth and survival of Salmonella associated with seeds that have been partially sprouted and dried. The goal of this study was to determine the growth of Salmonella during soaking for partial germination of pumpkin, sunflower, and chia seeds and subsequent survival during drying and storage. Pumpkin, sunflower, and chia seeds were inoculated with a four-serotype Salmonella cocktail by the dry transfer method and were soaked in sterile water at 25 or 37°C for 24 h. During the soaking period, Salmonella exhibited growth rates of 0.37 ± 0.26, 0.27 ± 0.12, and 0.45 ± 0.19 log CFU/h at 25°C and 0.94 ± 0.44, 1.04 ± 0.84, and 0.73 ± 0.36 log CFU/h at 37°C for chia, pumpkin, and sunflower seeds, respectively. Soaked seeds were drained and dried at 25, 51, and 60°C. Drying resulted in >5 log CFU/g loss at both 51 and 60°C and ∼3 log CFU/g loss at 25°C on partially sprouted pumpkin and sunflower seeds. There was no decrease in Salmonella during drying of chia seeds at 25°C, and only drying at 60°C provided losses >5 log CFU/g. Dried seeds were stored at 37 and 45°C at 15 and 76% relative humidity (RH) levels. The combination of temperature and RH exerted a stronger effect than either factor alone, such that rates at which Salmonella decreased generally followed this order: 37°C at 15% RH < 45°C at 15% RH < 37°C at 76% RH < 45°C at 76% RH for all seeds tested. Rates differed based on seed type, with chia seeds and chia seed powder having the smallest rate of Salmonella decrease, followed by sunflower and pumpkin seeds. Drying at higher temperatures (50 and 61°C) or storing at elevated temperature and humidity (45°C and 76% RH) resulted in significantly different
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Cross, Adam T; Turner, Shane R; Renton, Michael; Baskin, Jerry M; Dixon, Kingsley W; Merritt, David J
2015-04-01
Rock pools are small, geologically stable freshwater ecosystems that are both hydrologically and biologically isolated. They harbour high levels of plant endemism and experience environmental unpredictability driven by the presence of water over variable temporal scales. This study examined the hypothesis that the sediment seed bank in monsoon tropical freshwater rock pools would persist through one or more periods of desiccation, with seed dormancy regulating germination timing in response to rock pool inundation and drying events. Seeds were collected from seven dominant rock pool species, and germination biology and seed dormancy were assessed under laboratory conditions in response to light, temperature and germination stimulators (gibberellic acid, karrikinolide and ethylene). Field surveys of seedling emergence from freshwater rock pools in the Kimberley region of Western Australia were undertaken, and sediment samples were collected from 41 vegetated rock pools. Seedling emergence and seed bank persistence in response to multiple wetting and drying cycles were determined. The sediment seed bank of individual rock pools was large (13 824 ± 307 to 218 320 ± 42 412 seeds m(-2) for the five species investigated) and spatially variable. Seedling density for these same species in the field ranged from 13 696 to 87 232 seedlings m(-2). Seeds of rock pool taxa were physiologically dormant, with germination promoted by after-ripening and exposure to ethylene or karrikinolide. Patterns of seedling emergence varied between species and were finely tuned to seasonal temperature and moisture conditions, with the proportions of emergent seedlings differing between species through multiple inundation events. A viable seed bank persisted after ten consecutive laboratory inundation events, and seeds retained viability in dry sediments for at least 3 years. The persistent seed bank in freshwater rock pools is likely to provide resilience to plant
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Pawłowski, Tomasz Andrzej; Staszak, Aleksandra Maria
2016-05-20
Acer pseudoplatanus seeds are characterized by a deep physiological embryo dormancy that requires a few weeks of cold stratification in order to promote germination. Understanding the function of proteins and their related metabolic pathways, in conjunction with the plant hormones implicated in the breaking of seed dormancy, would expand our knowledge pertaining to this process. In this study, a proteomic approach was used to analyze the changes occurring in seeds in response to cold stratification, which leads to dormancy release. In addition, the involvement of abscisic (ABA) and gibberellic acids (GA) was also examined. Fifty-three proteins showing significant changes were identified by mass spectrometry. An effect of ABA on protein variation was observed at the beginning of stratification, while the influence of GA on protein abundance was observed during the middle phase of stratification. The majority of proteins associated with dormancy breaking in the presence of only water, and also ABA or GA, were classified as being involved in metabolism and genetic information processing. For metabolic-related proteins, the effect of ABA on protein abundance was stimulatory for half of the proteins and inhibitory for half of the proteins. On the other hand, the effect on genetic information processing related proteins was stimulatory. GA was found to upregulate both metabolic-related and genetic information processing-related proteins. While seed dormancy breaking depends on proteins involved in a variety of processes, proteins associated with methionine metabolism (adenosine kinase, methionine synthase) and glycine-rich RNA binding proteins appear to be of particular importance. Copyright © 2016 Elsevier GmbH. All rights reserved.
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Staszak, Aleksandra Maria; Pawłowski, Tomasz Andrzej
2014-06-17
The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF). Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin) associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association.
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Carmen BEINSAN
2018-05-01
Full Text Available The purpose of the experiment was to highlight the germination of sunflower seeds affected by the presence of saline stress and the identification of tolerant genotypes. The biological material was represented by sunflower cvs. (Helianthus annuus L.: Coril, Select, Santiago and Fundulea-206. To simulate the saline conditions, germination solutions of sodium chloride (NaCl were used with concentrations corresponding to the osmotic pressures -6 and -10 atm and the control seed hydration was performed with distilled water. Determination of seed germination, growth of seedling, percentage of plumules dry matter, chlorophyll content and free proline were performed. The experimental data obtained suppose the existence in the assimilation apparatus of sunflowers seedling subjected to stress a competitive chlorophyll/free proline biosynthesis processes. The experimental results regarding the effect of salinity on seed germination and seedling growth revealed important differences between genotypes. The radicle growth in the germination process were strongly affected by saline excess, with significant differences between cultivars. Saline stress results in significant reductions in the amount of chlorophyll, and high levels of free proline. It can be observed that with the increase of the stress level the percentage of the dry matter increases, indicating an accentuated water deficit.
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Kassie L. Tilini; Susan E. Meyer; Phil S. Allen
2016-01-01
This study established that chilling removes primary seed dormancy in 2 rare penstemons of the western US, Gibbensâ beardtongue (Penstemon gibbensii Dorn [Scrophulariaceae]) and blowout penstemon (Penstemon haydenii S. Watson). Wild-harvested seeds were subjected either to moist chilling at 2 to 4 °C (36-39 °F) for 0, 4, 8, 12, and 16 wk or to approximately 2 y of dry...
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DRAGANIC, Ivana; LEKIC, Slavoljub
2012-01-01
The results of studying the effects of sunflower seed priming with an aqueous solution of ascorbic acid (A), tocopherol (T), and glutathione (G) performed prior to accelerated ageing and a cold test are presented in this paper. Germination, the percentage of abnormal seedlings, and the lengths of both roots and shoots were monitored. The results showed that the cold test caused a drastic drop in germination, an adverse effect on the shoot length, an increase in the percentage of abnormal seed...
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Bove, Jérôme; Lucas, Philippe; Godin, Béatrice; Ogé, Laurent; Jullien, Marc; Grappin, Philippe
2005-03-01
Seed dormancy in Nicotiana plumbaginifolia is characterized by an abscisic acid accumulation linked to a pronounced germination delay. Dormancy can be released by 1 year after-ripening treatment. Using a cDNA-amplified fragment length polymorphism (cDNA-AFLP) approach we compared the gene expression patterns of dormant and after-ripened seeds, air-dry or during one day imbibition and analyzed 15,000 cDNA fragments. Among them 1020 were found to be differentially regulated by dormancy. Of 412 sequenced cDNA fragments, 83 were assigned to a known function by search similarities to public databases. The functional categories of the identified dormancy maintenance and breaking responsive genes, give evidence that after-ripening turns in the air-dry seed to a new developmental program that modulates, at the RNA level, components of translational control, signaling networks, transcriptional control and regulated proteolysis.
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Chen, Shun-Ying; Chien, Ching-Te; Baskin, Jerry M; Baskin, Carol C
2010-02-01
The medicinal Asian plant genus Phellodendron is known to contain several very important compounds that have biological action. The main purpose of this study was to determine whether seeds of Phellodendron amurense var. wilsonii can be stored and to characterize their dormancy. Seeds of this taxon stored at -20 and -80 degrees C and in liquid nitrogen retained their high germinability, indicating that they have orthodox storage behavior. Intact seeds from freshly collected fruits were dormant and required 12 weeks of cold stratification at 4 degrees C for complete germination. Scarifying the seed coat was partially effective in breaking seed dormancy. Exogenous gibberellins (GA(3), GA(4) and GA(4+7)) promoted germination of scarified seeds, GA(4) and GA(4+7) being more effective than GA(3). Fluridone, an abscisic acid (ABA) biosynthesis inhibitor, was efficient in breaking dormancy, but it was less effective than GA(4) or GA(4+7) alone. Paclobutrazol, a GA biosynthesis inhibitor, inhibited seed germination, and the inhibitory effect was reversed completely by GA(4) and by GA(4+7). ABA content of seeds subjected to cold stratification or to incubation at 35/10 degrees C, which enhanced seed germination, was reduced about four- to sixfold compared to that of fresh seeds. Higher concentrations of GA(3), GA(4) and GA(7) were detected in nondormant seeds and in seeds with an emerged radicle than in fresh seeds. Present results seem to indicate that dormancy in P. amurense var. wilsonii seeds is imposed partially by the seed coat and partially by high ABA content. ABA content decreased and GA(3), GA(4) and GA(7) content increased during germination.
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Directory of Open Access Journals (Sweden)
Yuan M Zhou
Full Text Available The occurrence of various species of Brassicaceae with indehiscent fruits in the cold deserts of NW China suggests that there are adaptive advantages of this trait. We hypothesized that the pericarp of the single-seeded silicles of Isatis violascens restricts embryo expansion and thus prevents germination for 1 or more years. Thus, our aim was to investigate the role of the pericarp in seed dormancy and germination of this species. The effects of afterripening, treatment with gibberellic acid (GA3 and cold stratification on seed dormancy-break were tested using intact silicles and isolated seeds, and germination phenology was monitored in an experimental garden. The pericarp has a role in mechanically inhibiting germination of fresh seeds and promotes germination of nondormant seeds, but it does not facilitate formation of a persistent seed bank. Seeds in silicles in watered soil began to germinate earlier in autumn and germinated to higher percentages than isolated seeds. Sixty-two percent of seeds in the buried silicles germinated by the end of the first spring, and only 3% remained nongerminated and viable. Twenty to twenty-five percent of the seeds have nondeep physiological dormancy (PD and 75-80% intermediate PD. Seeds with nondeep PD afterripen in summer and germinate inside the silicles in autumn if the soil is moist. Afterripening during summer significantly decreased the amount of cold stratification required to break intermediate PD. The presence of both nondeep and intermediate PD in the seed cohort may be a bet-hedging strategy.
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Technological Desition of Extraction of Melanin from the Waste of Production of Sunflower-Seed Oil
Kartushina, Yu N.; Nefedieva, E. E.; Sevriukova, G. A.; Gracheva, N. V.; Zheltobryukhov, V. F.
2017-05-01
The research was realized in the field of the technology for re-use of waste of sunflower-seed oil production. A technological scheme of production of melanin from sunflower husk as a waste was developed. Re-cycling will give the opportunity to reduce the amount of waste and to obtain an additional source of income.
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Ye, Heng; Beighley, Donn H.; Feng, Jiuhuan; Gu, Xing-You
2013-01-01
Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of t...
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Salehani, M Khajavi; Mahmoudi, J; Mahdavi, S Kh; Habibzadeh, R
2013-01-01
Persian hogweed is a perennial herb and aromatic plant which has pharmaceutical and fodder values, and the main propagation method of this species is seed. The goal of this study was to investigate the effect of altitude on breaking dormancy and stimulate seed germination of this species. The study was designed and carried out using the test of seed analysis. For our purpose, seeds were collected from three different altitudes (1700, 2200, 2700 masl) in Kojoor area. After initial purification, germination percent (GP) and speed (GS) of each elevation were determined by cold stratification compared to control. According to results, control seeds did not germinate, showing that the seeds of this species need to be treated. Statistical analysis of results showed that there are significant differences between GP and GS of each elevation, as seeds of higher elevation had slower and less germination in longer periods. So, changes in elevation are an effective factor on seed germination characteristics of this species and this factor has to be considered in seed preparation and restoration with this species.
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Taylor, Mark A; Cooper, Martha D; Sellamuthu, Reena; Braun, Peter; Migneault, Andrew; Browning, Alyssa; Perry, Emily; Schmitt, Johanna
2017-10-01
Major alleles for seed dormancy and flowering time are well studied, and can interact to influence seasonal timing and fitness within generations. However, little is known about how this interaction controls phenology, life history, and population fitness across multiple generations in natural seasonal environments. To examine how seed dormancy and flowering time shape annual plant life cycles over multiple generations, we established naturally dispersing populations of recombinant inbred lines of Arabidopsis thaliana segregating early and late alleles for seed dormancy and flowering time in a field experiment. We recorded seasonal phenology and fitness of each genotype over 2 yr and several generations. Strong seed dormancy suppressed mid-summer germination in both early- and late-flowering genetic backgrounds. Strong dormancy and late-flowering genotypes were both necessary to confer a winter annual life history; other genotypes were rapid-cycling. Strong dormancy increased within-season fecundity in an early-flowering background, but decreased it in a late-flowering background. However, there were no detectable differences among genotypes in population growth rates. Seasonal phenology, life history, and cohort fitness over multiple generations depend strongly upon interacting genetic variation for dormancy and flowering. However, similar population growth rates across generations suggest that different life cycle genotypes can coexist in natural populations. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
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Huang, Z; Footitt, S; Tang, A; Finch-Savage, W E
2018-01-01
Seed characteristics are key components of plant fitness that are influenced by temperature in their maternal environment, and temperature will change with global warming. To study the effect of such temperature changes, Arabidopsis thaliana plants were grown to produce seeds along a uniquely designed polyethylene tunnel having a thermal gradient reflecting local global warming predictions. Plants therefore experienced the same variations in temperature and light conditions but different mean temperatures. A range of seed-related plant fitness estimates were measured. There were dramatic non-linear temperature effects on the germination behaviour in two contrasting ecotypes. Maternal temperatures lower than 15-16 °C resulted in significantly greater primary dormancy. In addition, the impact of nitrate in the growing media on dormancy was shown only by seeds produced below 15-16 °C. However, there were no consistent effects on seed yield, number, or size. Effects on germination behaviour were shown to be a species characteristic responding to temperature and not time of year. Elevating temperature above this critical value during seed development has the potential to dramatically alter the timing of subsequent seed germination and the proportion entering the soil seed bank. This has potential consequences for the whole plant life cycle and species fitness. © 2017 John Wiley & Sons Ltd.
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Directory of Open Access Journals (Sweden)
JOSENARA DAIANE DE SOUZA COSTA
2016-01-01
Full Text Available Considering the potential and importance of biodiversity of the Caatinga biome, studies on endemic species are relevant to conservation of its natural resources. The objectives of this work was to evaluate seed viability and physical methods for overcoming seed dormancy in juazeiro (Ziziphus joazeiro Mart. and assess the influence of different types of soil on the initial growth of juazeiro plants. The experiments were conducted in three stages. In the first stage, the viability of seeds from different lots was evaluated using the tetrazolium test. The second stage was conducted in a plant nursery, evaluating the application of physical processes (scarification with sandpaper and hammer in overcoming seed dormancy, and the initial growth of the plants. In the third step, the chlorophyll a and b contents, gas exchange and dry matter accumulation were evaluated in young juazeiro plants in three types of soil (Oxisol, Entisol and Vertisol. The results indicate that the viability of juazeiro seeds is greatly influenced by differences between the progenitor plants and by storage conditions, which enable a longevity of two years when stored at 22°C and 16% of relative humidity. The scarification methods with sandpaper and hammer are not efficient to reduce the time and uniform seed germination. The juazeiro plants have high growth potential in different edaphic environments, adapting well to soils of different textures and chemical compositions.
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Sunflower seed for human consumption as a substrate for the growth of mycopopulations
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Škrinjar Marija M.
2012-01-01
Full Text Available These mycological investigations are implicating samples of protein sunflower seed from regular cultivation in the Vojvodina Province. Samples are examined in different stages of production: reception in the silo, separation of massive fraction on peeler and then peeling, kernel after peeling, hull, final product, i.e. kernels separated from visible impurities on conveyor bel, that are later manually divided in two fractions - a seemingly whole, undamaged kernels, without change of colour, and b seemingly damaged kernels, broken, with change of colour. For the determination of viable count of moulds and their isolation, two different media are used in parallel: Sabouraud maltose agar (SMA and malt/yeast extract with 50% of glucose (MY50G, favourable for growth of xerophilic moulds. All samples tested were contaminated with fungi. Total viable mould count per seed varied from 1.6 (SMA respecting 1.3 (MY50G on reception, to 5.6 (SMA and 7.5 (MY50G cfu/seed in visually damaged sunflower kernels (final product. From seeds, kernels and hull, numerous moulds were isolated, belonging to 8 genera and 13 species (Alternaria alternata, Arthrinium phaeospermum, Aspergillus candidus, A. flavus, A. niger, A. ochraceus, A. versicolor, A. wentii, Cladosporium cladosporioides, Eurotium herbariorum, Penicillium aurantiogriseum, Rhizopus stolonifer and Trichoderma harzianum. Alternaria alternata, Aspergillus flavus, A.ochraceus, A. versicolor and Eurotium herbariorum were isolated on both media. Aspergillus candidus, A. versicolor, C. Cladosporioides, P. aurantiogriseum and T. harzianum were isolated only on SMA, while A. niger, A. wentii and R. stolonifer were exclusively isolated on MY50G. Most ubiquitous species is A. alternata, which is isolated from all tested samples, while A. candidus, C. cladosporioides and T. harzianum were isolated from sunflower seed on reception in silo, using SMA medium.
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Interrelationship of pollination conditions, fertilization and sunflower seed yield
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Joksimović Jovan
2005-01-01
Full Text Available Four commercially important sunflower hybrids (NS-H-45, NS-H-l 11, NS-H-702 and Velja and their parental components (Ha-74B, Ha-98B, CMS-3-8B, Ha-26B, RHA-583, RHA-R-PI-2/1 and RHA-113N were used over a period of two years to study the following traits: disk flower corolla length, nectar content, pollen viability, bee visitation, fertilization percentage and seed yield. Relations among the traits were determined by path coefficient analysis. The simple correlation coefficients showed that fertilization percentage and bee visitation had a highly significant influence on seed yield. The corolla length had a positive effect on nectar content, while nectar content had a significant negative influence on pollen viability. The highest significant direct influence on seed yield was that of fertilization percentage, while the effect on nectar content on seed yield was negative but not significant. The coefficient of determination was 0.8071.
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Engineering properties of sunflower seed: Effect of dehulling and moisture content
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Mudasir Ahmad Malik
2016-12-01
Full Text Available The study diagnosed engineering properties on varying moisture content of sunflower seed and kernel from 7.6 to 25% (wet basis. On increasing moisture, dimensional values increased for both seed and kernel. Bulk density, true density and porosity were found higher for kernel as compared to seed at each moisture content. On increasing the moisture content from 7.6 to 25%, true density, porosity and thousand kernel weight increased. Coefficient of static friction on plywood was found maximum for kernel at 25% moisture content, while it was minimum for seed on glass at 7.6% moisture content. The angle of repose was maximum for kernel as compared to seed. Initial cracking force, average rupture force and average rupture energy for seed and kernel decreased with an increase in the moisture content. The kernel was found to be more resistant to initial cracking than seed.
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physiological mechanisms for potato dormancy release
African Journals Online (AJOL)
ACSS
of deep dormancy, during which potato seeds do not germinate after ... dormancy period and sprouting behaviour are major criteria ... develop once sprouting begins; such as changes ...... an example of plant information processing. Plant Cell ...
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Riemens, M.M.; Scheepens, P.C.; Weide, van der R.Y.
2004-01-01
This note reports the results of an inventory study about the influence of the external factors temperature, light, nitrate, gaseous environment of seeds and moisture on the dormancy, germination and emergence of weed seeds. The inventory was made as a guideline for research aiming at the
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Effect of dried sunflower seeds on incisal edge abrasion: A rare case report.
Rath, Avita; Ramamurthy, Priyadarshini H; Fernandes, Bennete Aloysius; Sidhu, Preena
2017-01-01
Tooth surface loss (TSL) is a complex phenomenon characterized by the loss of hard tooth structure at various locations of the teeth, usually due to more than one factor. TSL due to abrasion can be significant in patients consuming coarse, abrasive diet. The present case reports an interesting incisal edge abrasion in a female patient, attributed to a particular dietary behavior of long-term consumption of sunflower seeds. All her family members and most of the people from her native place were also reported to have similar lesions by the patient. Larger epidemiological studies to assess the prevalence and severity of such abrasive lesions in geographic areas with this particular dietary habit need to be carried out so that people may be made aware and educated about alternative ways of eating sunflower seeds that will not cause any form of tooth wear.
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Directory of Open Access Journals (Sweden)
Vlad Mureşan
2015-11-01
Full Text Available Sunflower is the basic oil-crop in Central and Eastern Europe. As sunflower seeds are mainly used for oil production, the most of the kernels available on the market show high oil content (>55%. Consequently, when sunflower kernel paste (tahini is used in different food products, oil exudation occurs.The aim of current work was to use entirely the sunflower seeds by partially defatting and obtaining different fat content sunflower pastes with multiple food applications, while using the husks for developing an ecological package. Sunflower kernels were industrially roasted in a continuous roasting drum. Raw and roasted kernels were pressed at pilot plant scale by using a laboratory expeller. Partially defatted sunflower paste was obtained from the press cakes by employing a ball mill. Different fat content tahini samples were obtained by adding the required amount of oil to the partially defatted paste. Tahini samples fat content ranged from 45 to 60%. Tahini and halva were chosen as a study model. Decreasing tahini oil content increased its colloidal stability during storage, a similar trend being noticed when halva samples were stored. Moreover, halva texture analysis and sensory characteristics were assessed for selecting the optimum tahini oil content and thermal treatment. Various sunflower kernel food applications were proposed by obtaining the related prototypes at pilot plant scale: roasted sunflower kernel biscuits, sunflower spreadable cream filled biscuits, hummus, sunflower paste coated in chocolate, sunflower kernel chikki and bars, as well as an innovative ecological package based on the resulting sunflower husks and a starch adhesive.
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Wu, Jian; Seng, Shanshan; Sui, Juanjuan; Vonapartis, Eliana; Luo, Xian; Gong, Benhe; Liu, Chen; Wu, Chenyu; Liu, Chao; Zhang, Fengqin; He, Junna; Yi, Mingfang
2015-01-01
The phytohormone abscisic acid (ABA) regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and functional characterization of the Gladiolus ABI5 homolog (GhABI5), which is a basic leucine zipper motif transcriptional factor (TF). GhABI5 is expressed in dormant vegetative organs (corm, cormel, and stolon) as well as in reproductive organs (stamen), and it is up-regulated by ABA or drought. Complementation analysis reveals that GhABI5 rescues the ABA insensitivity of abi5-3 during seed germination and induces the expression of downstream ABA response genes in Arabidopsis thaliana (EM1, EM6, and RD29B). Down-regulation of GhABI5 in dormant cormels via virus induced gene silence promotes sprouting and reduces the expression of downstream genes (GhLEA and GhRD29B). The results of this study reveal that GhABI5 regulates bud dormancy (vegetative organ) in Gladiolus in addition to its well-studied function in Arabidopsis seeds (reproductive organ).
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Directory of Open Access Journals (Sweden)
Jian eWu
2015-11-01
Full Text Available The phytohormone abscisic acid (ABA regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and functional characterization of the Gladiolus ABI5 homolog (GhABI5, which is a basic leucine zipper motif transcriptional factor (TF. GhABI5 is expressed in dormant vegetative organs (corm, cormel and stolon as well as in reproductive organs (stamen, and it is up-regulated by ABA or drought. Complementation analysis reveals that GhABI5 rescues the ABA insensitivity of abi5-3 during seed germination and induces the expression of downstream ABA response genes in Arabidopsis thaliana (EM1, EM6 and RD29B. Down-regulation of GhABI5 in dormant cormels via Virus Induced Gene Silence (VIGS promotes sprouting and reduces the expression of downstream genes (GhLEA and GhRD29B. The results of this study reveal that GhABI5 regulates bud dormancy (vegetative organ in Gladiolus in addition to its well-studied function in Arabidopsis seeds (reproductive organ.
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Superação de dormência em sementes de Butia capitata Overcoming dormancy in seeds of Butia capitata
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Claudimar Sidnei Fior
2011-07-01
Full Text Available Com o objetivo de identificar métodos eficientes para a superação da dormência de sementes de B. capitata (Mart. Becc. semeadas in vitro e em germinador, foram conduzidos testes com escarificação mecânica em pré-semeadura, através da abertura parcial ou total da cavidade embrionária de sementes isoladas dos endocarpos. A abertura da cavidade embrionária acelerou significativamente a germinação, principalmente quando houve retirada total do opérculo da semente, permitindo a germinação de, em média, 90% dos embriões, independentemente da procedência dos acessos. A dormência das sementes de B. capitata parece estar relacionada com a barreira mecânica imposta pelos tecidos da semente que dificultam o desenvolvimento do embrião, o que sugere dormência exógena mecânica.Aiming to identify efficient conditions to break dormancy in Butia capitata (Mart. Becc. seeds sown in vitro and in an incubator tests were conducted with mechanical scarification in pre-sowing, by partial or total opening of the seed embryonic cavity, isolated of the endocarps. The embryonic cavity opening accelerated germination significantly, especially when there was total removal of the seed cap, allowing germination on average 90% of embryos, regardless of the provenance of the accessions. The seed dormancy of B. capitata seems to be related to the mechanical barrier imposed by the seed tissues that hamper the embryo development, suggesting mechanical exogenous dormancy.
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Susan E. Meyer; Phil S. Allen
2009-01-01
A principal goal of seed germination modelling for wild species is to predict germination timing under fluctuating field conditions. We coupled our previously developed hydrothermal time, thermal and hydrothermal afterripening time, and hydration-dehydration models for dormancy loss and germination with field seed zone temperature and water potential measurements from...
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Danby, Simon G; AlEnezi, Tareq; Sultan, Amani; Lavender, Tina; Chittock, John; Brown, Kirsty; Cork, Michael J
2013-01-01
Natural oils are advocated and used throughout the world as part of neonatal skin care, but there is an absence of evidence to support this practice. The goal of the current study was to ascertain the effect of olive oil and sunflower seed oil on the biophysical properties of the skin. Nineteen adult volunteers with and without a history of atopic dermatitis were recruited into two randomized forearm-controlled mechanistic studies. The first cohort applied six drops of olive oil to one forearm twice daily for 5 weeks. The second cohort applied six drops of olive oil to one forearm and six drops of sunflower seed oil to the other twice daily for 4 weeks. The effect of the treatments was evaluated by determining stratum corneum integrity and cohesion, intercorneocyte cohesion, moisturization, skin-surface pH, and erythema. Topical application of olive oil for 4 weeks caused a significant reduction in stratum corneum integrity and induced mild erythema in volunteers with and without a history of atopic dermatitis. Sunflower seed oil preserved stratum corneum integrity, did not cause erythema, and improved hydration in the same volunteers. In contrast to sunflower seed oil, topical treatment with olive oil significantly damages the skin barrier, and therefore has the potential to promote the development of, and exacerbate existing, atopic dermatitis. The use of olive oil for the treatment of dry skin and infant massage should therefore be discouraged. These findings challenge the unfounded belief that all natural oils are beneficial for the skin and highlight the need for further research. © 2012 Wiley Periodicals, Inc.
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Bentsink, L.; Koornneef, M.
2002-01-01
Arabidopsis possesses dormancy, as is the case for many other plant species, which is controlled by environmental factors such as light, temperature and time of dry storage as well as by genetic factors. The use of genetics and molecular genetics in Arabidopsis is starting to shed light on some
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Nyam, K L; Teh, Y N; Tan, C P; Kamariah, L
2012-08-01
In order to overcome the stability problems of oils and fats, synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butyl hydroquinone (TBHQ) have widespread use as food additives in many countries. Recent reports reveal that these compounds may be implicated in many health risks, including cancer and carcinogenesis. Hence, there is a move towards the use of natural antioxidants of plant origin to replace these synthetic antioxidants. In this study, roselle seed oil (RSO) and extract (RSE) were mixed with sunflower oil, respectively to monitor degradation rate and investigate antioxidant activity during accelerated storage. The antioxidant activity was found to stabilise sunflower oil of various samples and in the order of RSE>RSO>tocopherol>sunflower oil. The total percentage increased after 5 days of storage period in free fatty acid (FFA), peroxide value (PV) and anisidine value (AV). Total oxidation value (TOx) of sunflower oil supplemented with 1500 ppm RSE was 33.3%, 47.7%, 14.5%, and 45.5%, respectively. While the total percentage increased under different analysis methods, sunflower oil supplemented with 5% RSO was 17.2%, 60.4%, 36.2% and 59.0% in the order of FFA, PV, AV and TOTOX. Both RSO and RSE were found to be more effective in stabilisation of sunflower oil compared to tocopherol. Total phenolic content of RSE was 46.40 +/- 1.51 mg GAE/100g of oil while RSO was 12.51 +/- 0.15 mg GAE/ 100g of oil. The data indicates that roselle seed oil and seed extract are rich in phenolics and antioxidant activities and may be a potential source of natural antioxidants.
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Defining the role of fire in alleviating seed dormancy in a rare Mediterranean endemic subshrub.
Cross, Adam T; Paniw, Maria; Ojeda, Fernando; Turner, Shane R; Dixon, Kingsley W; Merritt, David J
2017-09-01
Fire is a topical issue in the management of many ecosystems globally that face a drying climate. Understanding the role of fire in such ecosystems is critical to inform appropriate management practices, particularly in the case of rare and ecologically specialized species. The Mediterranean heathlands are highly fire-prone and occur in a biodiversity hotspot increasingly threatened by human activities, and determining the reproductive thresholds of at-risk heathland species is critical to ensuring the success of future conservation initiatives. This study examined the germination biology of the threatened carnivorous subshrub Drosophyllum lusitanicum , with specific focus on the role of fire-related cues (heat and smoke) in combination with seasonal temperatures and moisture conditions to determine how these factors regulate seed dormancy and germination. We found that D. lusitanicum produces water-permeable, physiologically dormant seeds with a fully developed, capitate embryo that when fresh (~1 month old) and without treatment germinate to 20-40 % within 4-8 weeks. Seeds possess a restricted thermal window (15-20 °C) for germination and a neutral photoblastic response. Seed dormancy was overcome through precision nicking of the seed coat (>90 % germination) or by short exposure to dry heat (80 or 100 °C) for 5-30 min (60-100 % germination). We propose seedling emergence from the soil seed bank may be cued by the passage of fire, or by soil disturbance from the movement and browsing of animals. Long-term population viability is likely to be contingent upon appropriate management of the persistent soil seed bank, as well as the adequate management of key ecological disturbances such as fire. Drosophyllum lusitanicum faces an increasingly bleak future in the absence of conservation and management initiatives aimed at reducing habitat fragmentation in heathlands and aligning fire management and livestock practices with biodiversity outcomes.
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Sunflower growth according to seed inoculation with endophytic bacteria
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Juliana Fernandes dos Santos
2014-06-01
Full Text Available The sunflower crop has a great importance worldwide, due to the oil of excellent quality extracted from its seeds and in natura grains that are consumed in various ways. However, drought is one of the main environmental factors that limit its yield. An experiment was carried out under controlled greenhouse conditions, in a completely randomized experimental design, in order to determine the effect of endophytic bacteria inoculation (Bacillus sp. and Enterobacter cloacae on the growth and contents of nutrients and organic solutes, in sunflower leaves and roots under water deficit. Plant height, stem diameter, fresh and dry biomass of shoot and roots, as well as contents of N, P, K, soluble carbohydrates, free proline, free amino acids and soluble proteins, were determined at 35 days after the plant emergence. The water deficit reduced plant growth regardless inoculation. However, under optimum conditions of soil moisture, the combination of both endophytic bacteria increased the sunflower growth. The water deficit also increased the N and K contents in leaves, as well as the organic solutes content in shoots, especially in inoculated plants. These results suggest that the inoculation of endophytic bacteria may increase the capacity of drought stressed plants to perform the osmotic adjustment through a higher accumulation of organic solutes, when compared to plants not inoculated.
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Role of np fertilizer under different application methods on seed yield of sunflower
International Nuclear Information System (INIS)
Khan, R.U.; Khan, R.A.; Khan, R.A.; Muendal, H.
2007-01-01
The effects of different application methods of nitrogen and phophorus fertilizers were studied on the sunflower hybrid NK-212 during spring and kharif seasons at National Agricultural Research Centre, Islamabad. Nitrogen and phosphorus were applied at the rate 90 and 60 kg P 2 degree 5 ha-1 in a different proportions i.e. all broadcast and disked, 3/4 broadcast disked + 1/4 side banded, 1/2 broadcast disked + 1/2 side banded, 1/4 broadcast disked + 3/4 side banded and all side banded. Fertilizer applied in equal proportions of side banded and broadcast at the time of planting gave maximum (1525 and 1348 kg ha-1) seed yield and largest (14.3 cm and 10.15 cm) head diameter of sunflower in spring seasons during (1987 and 1988), and seed yield of 1206 kg ha-1 and 11.0 cm head diameter during kharif 1987. A significant increase in the 1000 seed weight was also observed in all the treatments receiving different split applications of N and P over all broadcast applied fertilizer. Plant height was not increased by split applications, with lowest height to be associated with most side banding of fertilizers. (author)
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Electrochemical capacitive performances of nanoporous carbon derived from sunflower seed shell
Energy Technology Data Exchange (ETDEWEB)
Li, X; Xing, W.; Zhuo, S.; Zhou, J. [Shandong Univ. of Technology, Zibo (China). School of Chemical Engineering
2010-07-01
Electrochemical double-layer capacitances (EDLCs) are used in applications were high power density and long cycle life are required. Nanoporous materials are typically used to prepare EDLC electrodes due to their high surface area, good physicochemical stability, and high conductivity. In this study, nanoporous carbon materials were prepared from sunflower seed shells and used as an electrode material for an EDLC. The surface and structural properties of the carbon materials were analyzed using N{sub 2} adsorption and scanning electron microscopy (SEM) techniques. The study showed that AC-X-Y carbons prepared using the impregnation-activation process had a better capacitive behaviour and higher capacitance retention ratio at fast charge-discharge rates than carbons made using the carbonization-activation process. The improved electrochemical performance of the carbons was attributed to the abundant macroscopic pores and decreased interior micropore surface. The specific capacitances of the carbon was approximately twice that of a hard-templated mesoporous carbon in all current densities ranging from 0.25 to 10 A per g. Results indicated that sunflower seed shells can be used to prepare EDLCs. 2 refs., 1 fig.
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Thermal neutron activation analysis of different varieties of mustard and sunflower seeds
International Nuclear Information System (INIS)
Rajurkar, N.S.; Bhamare, C.S.
1991-01-01
Neutron activation analysis (NAA) technique has been used for the estimation of Mn, Na and K in different varietes of oil seeds of mustard and sunflower in India. The samples were irradiated in a 252 Cf source with neutron flux of ∼10 9 n s -1 and the analysis was done using a multichannel analyzer (MCA) coupled to high purity germanium (HPGe) detector. Different varieties of seeds are found to have different concentrations of tracer elements when compared among themselves. (author) 5 refs.; 1 fig.; 1 tab
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Graeber, K.; Linkies, A.; Steinbrecher, T.; Tarkowská, D. (Danuše); Turečková, V. (Veronika); Ignatz, M.; Voegele, A.; Urbanová, T. (Terezie); Strnad, M. (Miroslav); Leubner-Metzger, G. (Gerhard)
2014-01-01
Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the DELAY OF GERMINATION 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapp...
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Directory of Open Access Journals (Sweden)
Hanne N. Rasmussen
2012-02-01
Full Text Available A successful in situ germination experiment with Cypripedium calceolus, the European Lady’s slipper, is reported here for the first time. The seeds originated from controlled pollinations within and between two closely related Danish populations. The seeds were sown ripe in seed packets in proximity of mother plants. Germination was first observed after 4.5 y in the ground, following two successive cold and snowy winters, and only in one population. Seedlings expanded through the sides of the broken testa and were hair-less. A corresponding set of seeds, germinated in vitro as asymbiotic controls, responded positively to repeated cold stratifications after long incubation, suggesting that time (leaching? and chilling are dormancy breakage factors.
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Improvement of sunflower for consumption
Directory of Open Access Journals (Sweden)
Dijanović Dijana
2003-01-01
Full Text Available Growing sunflower (Heliianthus annuus L for consumption is becoming more and more attractive in the whole world and in our country, as well. The consumption of this product has been considerably increased because it is being used more and more in various forms: sunflower seed in a hull, hulled kernels fried or non-fried, salted or non-salted with addition of various spices. The sunflower kernel is used for preparing over 100 different food products: special types of bread, cakes, ice-cream, chocolate. In accordance with the trade demands, the aims of sunflower seeds for consumption improvement are: high productivity, greater content of proteins, lesser content of oil, oncreased mass of 1000 seeds, lesser portion of the hull easy nibbling, as well as tolerance to dominant diseases in the growing region. In the Agricultural and Technological Research Center in Zajecar, 4 genotypes of protein sunflower (two cultivars and two hybrids have been created so far. This study shows the results achieved in increasing the content of protein, the mass of 1000 seeds, decreasing the content of oil and hull of the new 90 hybrid combination. The hybrid combinations were obtained by crossing of the CMS and restorer lines.
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McNeece, Molly
2010-01-01
In this article, the author illustrates how she shares her love of sunflowers with her kindergarten and first-grade students through an interesting art lesson. Sunflowers are easy to grow, so the author started the lesson four months earlier with inexpensive seed packets. She planted many varieties, but she most likes the colors of the Mexican…
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DOG1-imposed dormancy mediates germination responses to temperature cues
Murphey, M.; Kovach, K.; Elnacash, T.; He, H.; Bentsink, L.; Donohue, K.
2015-01-01
Seed dormancy and environment-dependent germination requirements interact to determine the timing of germination in natural environments. This study tested the contribution of the dormancy gene Delay Of Germination 1 (DOG1) to primary and secondary dormancy induction in response to environmental
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The effect of fire on the dormancy break of annual legume seeds
Directory of Open Access Journals (Sweden)
Fabio Gresta
2011-07-01
Full Text Available Fire is a common phenomenon in the Mediterranean environment and strongly influences vegetal population dynamics through its impact on vegetation and the soil seed bank. Fire is able to break down the seed coat of hard-seeded legumes within the soil and trigger germination. To evaluate the effect of fire on the dormancy break in Medicago ciliaris, Medicago rugosa and Scorpiurus muricatus subsp. subvillosus, the seeds were placed at three different depths (surface, 25 mm and 50 mm and subjected to fires at two different intensities (high and low. As a control sample, a batch of seeds was buried at 25 mm for the duration of the trial and not subjected to fire. Soil temperatures during the fire were compared directly to stubble quantity and indirectly related to soil depth. The two Medicago species survived exposure to 90°C for a few minutes and displayed a significant increase in germination with exposure to high temperatures (over 70°C for several minutes. On the other hand, no germination occurred in Scorpiurus, irrespective of treatment. In conclusion, fire had a significant and positive effect in triggering germination of the Medicago species, but the dispersal strategies of these hard-seeded legumes are only partially interrupted by fire as a large number of seeds (>50% remained non-germinated in the soil.
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Directory of Open Access Journals (Sweden)
Mohammad Rezvani
2014-12-01
Full Text Available Shepherd's purse (Capsella bursa-pastoris is a problematic weed in citrus orchards and crop fields in northern Iran. In a series of laboratory and greenhouse experiments, we evaluated the effects that treatment with gibberellic acid (GA3 and potassium nitrate (KNO3, as well as environmental factors, including temperature, the duration of pre-chilling (wet and dry, drought stress, salt stress, pH, and sowing depth, have on seed dormancy breaking and germination in C. bursa-pastoris. Treatment with GA3 strongly stimulated germination of C. bursa-pastoris in conditions of light/dark and continuous darkness. The germination rate was highest (40.08% for seeds treated with 400 ppm of GA3 in the light/dark condition. Treatment with KNO3 did not significantly influence seed germination. Longer wet pre-chilling promoted germination and was more successful in seed dormancy breaking than was dry pre-chilling. Seed germination occurred at 10-30ºC and within a range of pH of 3-11. Drought and salt stress both strongly inhibited germination. Seedling emergence decreased in proportion to sowing depth. The rates of C. bursa-pastoris germination and seedling emergence were highest for seeds on the soil surface.
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A note on self heating and spontaneous combustion of stored sunflower seed cake and cotton seeds
International Nuclear Information System (INIS)
El-Nazir, S. M. A.; Babikir, I. H.; Shakak, M. A. S.; Sulieman, I. A.; Medani, R. M.
2012-01-01
Sunflower seed cake and cotton seed warehouses combusted spontaneously and burnt in August and November 2009, respectively, in Khartoum North industrial area. The objective of this study was to determine some of the reasons for self-heating and spontaneous combustion. Representative sample from the two warehouses were collected. Aspergillus niger, A. flavus, paecilomyces sp., Rhizopus oryzae, Absidia sp. were isolated at 37°C. Bacillus thuringiensis was isolated at 37°C and B. pantothenticus, B. circulans, B. licheniformis, B. sphaericus, B. badius, Escherichia coli and klebsiella sp. were isolated at 60°C. A decrease in soil, fiber and phosphorus and increase in free fatty acids and protein contents were detected.(Author)
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Cellular recycling of proteins in seed dormancy alleviation and germination
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Krystyna Oracz
2016-07-01
Full Text Available Each step of the seed-to-seed cycle of plant development including seed germination is characterized by a specific set of proteins. The continual renewal and/or replacement of these biomolecules are crucial for optimal plant adaptation. As proteins are the main effectors inside the cells, their levels need to be tightly regulated. This is partially achieved by specific proteolytic pathways via multicatalytic protease complexes defined as 20S and 26S proteasomes. In plants, the 20S proteasome is responsible for degradation of carbonylated proteins, while the 26S being a part of ubiquitin-proteasome pathway (UPP is known to be involved in proteolysis of phytohormone signaling regulators. On the other hand, the role of translational control of plant development is also well documented, especially in the context of pollen tube growth and light signaling. Despite the current progress that has been made in seed biology, the sequence of cellular events that determine if the seed can germinate or not are still far from complete understanding. The role and mechanisms of regulation of proteome composition during processes occurring in the plant’s photosynthetic tissues have been well characterized since many years, but in nonphotosynthetic seeds it has emerged as a tempting research task only since the last decade. This review discusses the recent discoveries providing insights into the role of protein turnover in seed dormancy alleviation, and germination, with a focus on the control of translation and proteasomal proteolysis. The presented novel data of translatome profiling in seeds highlighted that post-transcriptional regulation of germination results from a timely regulated initiation of translation. In addition, the importance of 26S proteasome in the degradation of regulatory elements of cellular signaling and that of the 20S complex in proteolysis of specific carbonylated proteins in hormonal- and light-dependent processes occurring in seeds is
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Tozer, Mark G.; Ooi, Mark K. J.
2014-01-01
Background and aims Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. Methods The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972–2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. Key Results A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (<20 %). Prolonged exposure at higher humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33–55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Conclusions Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic
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Ye, Heng; Beighley, Donn H; Feng, Jiuhuan; Gu, Xing-You
2013-02-01
Seed dormancy and plant height have been well-studied in plant genetics, but their relatedness and shared regulatory mechanisms in natural variants remain unclear. The introgression of chromosomal segments from weedy into cultivated rice (Oryza sativa) prompted the detection of two clusters (qSD1-2/qPH1 and qSD7-2/qPH7) of quantitative trait loci both associated with seed dormancy and plant height. Together, these two clusters accounted for >96% of the variances for plant height and ~71% of the variances for germination rate in an isogenic background across two environments. On the initial introgression segments, qSD1-2/qPH1 was dissected genetically from OsVp1 for vivipary and qSD7-2/qPH7 separated from Sdr4 for seed dormancy. The narrowed qSD1-2/qPH1 region encompasses the semidwarf1 (sd1) locus for gibberellin (GA) biosynthesis. The qSD1-2/qPH1 allele from the cultivar reduced germination and stem elongation and the mutant effects were recovered by exogenous GA, suggesting that sd1 is a candidate gene of the cluster. In contrast, the effect-reducing allele at qSD7-2/qPH7 was derived from the weedy line; this allele was GA-insensitive and blocked GA responses of qSD1-2/qPH1, including the transcription of a GA-inducible α-amylase gene in imbibed endosperm, suggesting that qSD7-2/qPH7 may work downstream from qSD1-2/qPH1 in GA signaling. Thus, this research established the seed dormancy-plant height association that is likely mediated by GA biosynthesis and signaling pathways in natural populations. The detected association contributed to weed mimicry for the plant stature in the agro-ecosystem dominated by semidwarf cultivars and revealed the potential benefit of semidwarf genes in resistance to preharvest sprouting.
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Dormancy contributes to the maintenance of microbial diversity.
Jones, Stuart E; Lennon, Jay T
2010-03-30
Dormancy is a bet-hedging strategy used by a variety of organisms to overcome unfavorable environmental conditions. By entering a reversible state of low metabolic activity, dormant individuals become members of a seed bank, which can determine community dynamics in future generations. Although microbiologists have documented dormancy in both clinical and natural settings, the importance of seed banks for the diversity and functioning of microbial communities remains untested. Here, we develop a theoretical model demonstrating that microbial communities are structured by environmental cues that trigger dormancy. A molecular survey of lake ecosystems revealed that dormancy plays a more important role in shaping bacterial communities than eukaryotic microbial communities. The proportion of dormant bacteria was relatively low in productive ecosystems but accounted for up to 40% of taxon richness in nutrient-poor systems. Our simulations and empirical data suggest that regional environmental cues and dormancy synchronize the composition of active communities across the landscape while decoupling active microbes from the total community at local scales. Furthermore, we observed that rare bacterial taxa were disproportionately active relative to common bacterial taxa, suggesting that microbial rank-abundance curves are more dynamic than previously considered. We propose that repeated transitions to and from the seed bank may help maintain the high levels of microbial biodiversity that are observed in nearly all ecosystems.
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Effect of seed quality on oxidative stability of cold-pressed sunflower oil
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Dimić Etelka B.
2015-01-01
Full Text Available The objective of this study was to investigate the impact of the storage time, content of the husk and impurities in the seed mass on the oxidative stability of the cold pressed sunflower oil. The oxidative stability of oil was analyzed by the RSM (Response Surface Methodology, where the response value (output of the model was the content of oxidation products measured via specific absorbance at 232 nm for conjugated dienes and 270 nm for conjugated trienes. Analyses were performed on the fresh oil samples and oil samples tempered under the Schaal-Oven’s test conditions (96 h at 63±2ºC. It was concluded that the seed storage time had significant impact on the primary (A1%232nm and secondary (A1%270nm oil oxidation products, both before (b1-p<0,001; b1-p=0,021 and after (b1-p=0,048; b1-p=0,033 the heating of oil. The content of impurities and husks in the seeds used for pressing also had an influence of the conjugated dienes and trienes contents in both, fresh and heated oil samples. However, their impact was not statistically significant. Interaction of seed storage time, the content of impurities and husks also exert some effect on the values of these quality parameters in the fresh oil as well as in the oil after the heat treatment, even though their influence is not significant. The obtained results have shown that the cold pressed sunflower oil had a good oxidative stability at temperatures up to 63±2ºC.
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Effect of hybrid, storage conditions and seed protection on sunflower field emergence
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Mrđa Jelena
2010-01-01
Full Text Available Seed emergence under field conditions decisively and directly determines the number of plants per hectare, which is one of three basic components of yield in the plant world. Influence of chemical treatment on field emergence of three commercial sunflower hybrids stored in different conditions was tested in 2007 and 2008 on experimental field of Institute of Field and Vegetable Crops in Novi Sad. On average, hybrid H1 had the highest value of field emergence (88.79% and for chemical treatment fl udioxonil + metalaxyl + imidacloprid (87.71%. Seed kept in common storage had the highest emergence value in fi eld (87.92%. Seed treated with fl udioxonil + metalaxyl + imidacloprid and stored for one year in common storage had the highest field emergence (90.18%. Considering interaction between storage conditions and genotype, hybrid H1 seed sown after chemical treatment had the highest field emergence (91.82% and seed kept in common storage (90.48%. Hybrid H1 seed compared with other two had the highest field emergence treated with fludioxonil + metalaxyl + imidacloprid (91.84%.
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Tozer, Mark G; Ooi, Mark K J
2014-09-01
Seed dormancy enhances fitness by preventing seeds from germinating when the probability of seedling survival and recruitment is low. The onset of physical dormancy is sensitive to humidity during ripening; however, the implications of this mechanism for seed bank dynamics have not been quantified. This study proposes a model that describes how humidity-regulated dormancy onset may control the accumulation of a dormant seed bank, and seed experiments are conducted to calibrate the model for an Australian Fabaceae, Acacia saligna. The model is used to investigate the impact of climate on seed dormancy and to forecast the ecological implications of human-induced climate change. The relationship between relative humidity and dormancy onset was quantified under laboratory conditions by exposing freshly matured non-dormant seeds to constant humidity levels for fixed durations. The model was field-calibrated by measuring the response of seeds exposed to naturally fluctuating humidity. The model was applied to 3-hourly records of humidity spanning the period 1972-2007 in order to estimate both temporal variability in dormancy and spatial variability attributable to climatic differences among populations. Climate change models were used to project future changes in dormancy onset. A sigmoidal relationship exists between dormancy and humidity under both laboratory and field conditions. Seeds ripened under field conditions became dormant following very short exposure to low humidity (humidity did not increase dormancy significantly. It is predicted that populations growing in a temperate climate produce 33-55 % fewer dormant seeds than those in a Mediterranean climate; however, dormancy in temperate populations is predicted to increase as a result of climate change. Humidity-regulated dormancy onset may explain observed variation in physical dormancy. The model offers a systematic approach to modelling this variation in population studies. Forecast changes in climate have
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Cell signaling mechanisms and metabolic regulation of germination and dormancy in barley seeds
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Zhenguo Ma
2017-12-01
Full Text Available During germination of barley (Hordeum vulgare L. seeds, important morphological and physiological changes take place, including development of organs and tissues and activation of metabolic pathways. Germination and dormancy of seeds are regulated by abscisic acid, gibberellins, reactive oxygen species (ROS, reactive nitrogen species (RNS and several other factors. Activities of ascorbateâglutathione cycle enzymes, responsible for scavenging ROS, strongly increase. Catalase and superoxide dismutase activities, also scavenging ROS, decrease at the onset of seed germination and then increase. With the increase in aerobic metabolism after radicle protrusion, the activities of the fermentation enzymes lactate and alcohol dehydrogenase decline rapidly. The RNS-scavenging activity of S-nitrosoglutathione reductase decreases in the course of seed germination, in concert with elevation of nitric oxide production and protein nitrosylation. This activity supports the role of RNS in regulating seed germination. Transcription of various genes at different phases of seed germination exhibits phase-specific changes. During imbibition, genes involved in cell wall metabolism are highly expressed; in the middle phase of seed germination before radicle protrusion, genes involved in amino acid synthesis, protein synthesis, and transport and nucleic acid synthesis are upregulated significantly, and after radicle protrusion, genes involved in photosynthetic metabolism are induced. In summary, signal transduction and metabolic regulation of seed germination involve diverse reactions and complex regulation at different levels of metabolic organization. Keywords: Seed germination, Reactive oxygen species, Reactive nitrogen species, Signal transduction, Gene expression
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The effect of fire on the dormancy break of three annual legume seeds
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Fabio Gresta
2011-07-01
Full Text Available Fire is a common phenomenon in the Mediterranean environment and strongly influences vegetal population dynamics through its impact on vegetation and the soil seed bank. Fire is able to break down the seed coat of hard-seeded legumes within the soil and trigger germination. To evaluate the effect of fire on the dormancy break in Medicago ciliaris, Medicago rugosa and Scorpiurus muricatus subsp. subvillosus, the seeds were placed at three different depths (surface, 25 mm and 50 mm and subjected to fires at two different intensities (high and low. As a control sample, a batch of seeds was buried at 25 mm for the duration of the trial and not subjected to fire. Soil temperatures during the fire were compared directly to stubble quantity and indirectly related to soil depth. The two Medicago species survived exposure to 90°C for a few minutes and displayed a significant increase in germination with exposure to high temperatures (over 70°C for several minutes. On the other hand, no germination occurred in Scorpiurus, irrespective of treatment. In conclusion, fire had a significant and positive effect in triggering germination of the Medicago species, but the dispersal strategies of these hard-seeded legumes are only partially interrupted by fire as a large number of seeds (>50% remained non-germinated in the soil.
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Havser ERTEM VAİZOĞULLAR
2015-01-01
Full Text Available This study compares the effects of different doses gamma radiation on crude oil yield and moisture of different six variety sunflower (Helianthus annuus L. seeds. As materials, sunflower variety Ege-2001, Turay, AS-508, Tunca, TR-3080 and Tarsan-1018 seeds were used and irradiated with doses of 0 (control, 100, 200, 300, 400 and 500 Gy gamma radiation. Irradiation was performed in a cesium (Ce137 Gammacell 3000 Elan source, dose rate about 9.75 Gy/min (2900 Ci in the Pamukkale University Faculty of Medicine in the department of the radiological. Moisture amount of seeds were also measured by AOCS standarts. Extraction of the seeds was done with soxhlet apparatus using petroleum ether by hot continuous extraction for 6 hours. It was found that the highest moisture rate in 100 Gy for all seeds variety. The moisture rate ranged between 3.00 and 9.68% in TR-3080 and Ege-2001, respectively. According to the our results, seed moisture content was affected by gamma radiation in a significant negative one-way. The significant reduction in seed moisture content (9.68% began at 100 Gy of gamma rays and continued to decline to up to 4.04% at 500 Gy. The crude oil yield showed not a important increase in 100 and 200 Gy doses. The result showed that the highest crude oil yield was also obtained from 400 Gy and 33.49% in Ege-2001 seeds.
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Diversity of sunflower pollinators and their effect on seed yield in Makueni District, Eastern Kenya
Nderitu, J.; Nyamasyo, G.; Kasina, M.; Oronje, M. L.
2008-01-01
A field experiment was carried out in 2004 and 2005 to identify the diversity of sunflower (Helianthus annuus L.) pollinators and their influence on seed yield in Makueni district, a semi-arid area in Eastern Kenya. Insect flower visitors were recorded, pollen counted from their body and pollination efficiency index for each visitor determined. Seed yield from plots where insect visitors had access to and where they were denied access was compared. The proportional difference of yield from th...
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Energy utilisation of biowaste - Sunflower-seed hulls for co-firing with coal
Energy Technology Data Exchange (ETDEWEB)
Raclavska, Helena; Juchelkova, Dagmar; Roubicek, Vaclav; Matysek, Dalibor [VSB-Technical University of Ostrava, 17. listopadu 15, CZ-70833 Ostrava (Czech Republic)
2011-01-15
Sunflower-seed hulls (SSH) represent a source of combustible biomass characterised by high contents of potassium and phosphorus and a low silica content. The relatively high net calorific value of 20 MJ/kg d.m. is mainly influenced by the lignin content. Potassium and phosphorus are very important elements in biomass combustion for fuel, influencing slagging and fouling problems. Mixtures with different ratios of brown coal and sunflower-seed hulls (0-22% SSH) were co-fired in the Olomouc power plant. The behaviour of elements in the fly ash and the bottom ash (SiO{sub 2}, Al{sub 2}O{sub 3}, K{sub 2}O, P{sub 2}O{sub 5}, Zn, Cu and Cd) varied in relation to the amount of SSH added to the coal. The fly ash from the co-firing of 20% SSH with coal had a high content of water-leachable sulphates and total dissolved solids. The utilisation of fly ash in civil engineering (land reclamation) should fulfil criteria established by the Council Decision 2003/33/EC for non-hazardous waste. To ensure that the required water-leachable sulphate concentrations are within regulatory limits the fuel may contain a maximum of 14% SSH. (author)
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Hassan HEIDARI
2013-02-01
Full Text Available One of the sources for irrigation is sewage. Contaminated water may affect seed germination and plant growth. A laboratory experiment and a pot experiment were conducted in 2012 to determine the effect of different doses of detergent on seed germination traits and early growth of sunflower (Helianthus annuus L.. The experiments included eight doses of cloth detergent (0, 0.00002, 0.0002, 0.002, 0.02, 0.2, 2, 20 g/L. Results showed that 20 and 2 g/L of detergent severely reduced seed germination, plant height, leaf number per plant, total biomass and stem weight. 20 g/L of detergent reduced shoot length, root length, seedling weight and seed vigor. Seed germination stage was more sensitive to contaminated water than early growth stage. The results demonstrated that irrigating sunflower by contaminated water with household cleaning products at high concentration should be avoided.
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Ashraf, Muhammad Yasin; Sadiq, Rumana; Hussain, Mumtaz; Ashraf, Muhammad; Ahmad, M Sajid Aqeel
2011-12-01
To assess the toxic effect of nickel (Ni) on the growth and some key metabolic processes in sunflower, varying levels of Ni as Ni(NO(3))(2) up to 60 mg L(-1) were applied once to sunflower cultivars SF-187 and Hysun-33 at sowing time in sand culture. An increase in Ni in the growth medium adversely affected growth parameters, sugar concentration (both reducing and non-reducing), as well as the activities of α-amylase and protease. It also slowed down mobilization of stored proteins and amino acids in the germinating seeds. However, an increase in the activities of α-amylase and protease was observed over time from 24 to 120 h after sowing. Cultivar Hysun-33 showed better performance than SF-187 in the presence of excess Ni. Overall, Ni-induced reduction in germination of sunflower seed appeared to be due to disturbance in biochemical metabolism as the availability of sugars for the synthesis of metabolic energy as well as necessary amino acids for the synthesis of proteins and enzymes essential for the growing embryo are generally reduced due to suppression in α-amylase and protease activities.
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Directory of Open Access Journals (Sweden)
Y. A. Dyachenko
2016-01-01
Full Text Available During the last decades becoming more sharply there is a problem of chemical and environmental monitoring and industrial inspection the content of toxic elements in food raw materials and foodstuff. At the same time there is a need to develop rapid methods, informative, integral, reflecting not only the safety but also the ecological purity of food raw materials. The method of determination of content of toxic elements on activity of its own lipase of in situ (AОL-method in seeds of oil-bearing crops, on the example of sunflower is offered. The system of mathematical assessment of analytical criteria of laboratory test used in clinical laboratory diagnostics was for this purpose adapted. Sunflower seeds in which established the maintenance of toxiferous elements served as an object of a research: Cd, Pb, As, Hg, by atomic absorption method on the KVANT-Z.ETA device. Further tests divided on clear, including high-quality and pollution-free, and polluted - naturally containing toxiferous elements and which are artificially contaminated. Definition of activity of a lipase of seeds was carried out by the standard titrimetric method. Decrease of the activity of enzyme was connected with the maintenance of toxiferous elements. Proceeding from the received results counted an analytical significance (sensitivity, specificity, and predictive value of descriptiveness the positive and negative results of determination of level of maintenance of toxiferous elements in sunflower seeds by the AОL-method. The set values of analytical specificity of a method and predictive value of a positive take at the level of 77.3% and 71.4% respectively, do not allow to use the offered method for the quantitative analysis, however, analytical sensitivity at the level of 86.2% and the predictive value of the negative result at the level of 89.5%, allow to recommend the AOL-method for screening programs of chemical environmental monitoring and technological monitoring of a
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Effects of Saline and Sodic Stress on Yield and Fatty Acid Profile in Sunflower Seeds
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Giovanna Cucci
2007-03-01
Full Text Available Among the objectives concerned in this research, much importance has been attached to the assessment of the influence of soil type, irrigation water quality and leaching requirement on the production and composition in fatty acids of sunflower oil. The trial was run in 2001 on a sunflower crop (cv. HS 90 grown in cylindrical pots at the Campus of Bari University (Italy. 36 treatments obtained from the factorial combination of two clay soils with nine types of brackish water and two leaching fractions (10 and 20% were compared. The nine types of irrigation water were obtained by dissolving the proper amounts of NaCl and CaCl2 in de-ionized water, according to the factorial combination of three salt concentration levels (0.01, 0.032 and 0.064 M with three sodium levels (SAR = 5, 15 and 45. At ripening the main yield traits, oil yield and acid composition of seeds were analysed. At the highest salinity level about 70% yield reduction, in terms of seeds per plant was observed. The oil yield and the final acid composition of seeds were significantly affected by soil type, leaching requirement, salinity and the SAR levels of irrigation water. A progressive decline in oil yield was recorded as the salt concentration and sodium level of irrigation solutions increased. As to the fatty acid composition, a gradual increase in oleic and linolenic acid content and a corresponding decrease in the other fatty acids were found as the salinity and sodium levels of irrigation water increased. The oleic/linoleic acid ratio too increased as the salinity increased. The salt and sodium-induced stresses of irrigation water reduced the seed and oil yields while still favouring a progressive increase in the oleic acid content and a slight decrease of linoleic, palmitic and stearic acids, thus improving oil quality. The results point out both the influence of the soil and the positive effect of sodium and salt stress and of the leaching fraction on the food quality of
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Effects of Saline and Sodic Stress on Yield and Fatty Acid Profile in Sunflower Seeds
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Emanuele Tarantino
2011-02-01
Full Text Available Among the objectives concerned in this research, much importance has been attached to the assessment of the influence of soil type, irrigation water quality and leaching requirement on the production and composition in fatty acids of sunflower oil. The trial was run in 2001 on a sunflower crop (cv. HS 90 grown in cylindrical pots at the Campus of Bari University (Italy. 36 treatments obtained from the factorial combination of two clay soils with nine types of brackish water and two leaching fractions (10 and 20% were compared. The nine types of irrigation water were obtained by dissolving the proper amounts of NaCl and CaCl2 in de-ionized water, according to the factorial combination of three salt concentration levels (0.01, 0.032 and 0.064 M with three sodium levels (SAR = 5, 15 and 45. At ripening the main yield traits, oil yield and acid composition of seeds were analysed. At the highest salinity level about 70% yield reduction, in terms of seeds per plant was observed. The oil yield and the final acid composition of seeds were significantly affected by soil type, leaching requirement, salinity and the SAR levels of irrigation water. A progressive decline in oil yield was recorded as the salt concentration and sodium level of irrigation solutions increased. As to the fatty acid composition, a gradual increase in oleic and linolenic acid content and a corresponding decrease in the other fatty acids were found as the salinity and sodium levels of irrigation water increased. The oleic/linoleic acid ratio too increased as the salinity increased. The salt and sodium-induced stresses of irrigation water reduced the seed and oil yields while still favouring a progressive increase in the oleic acid content and a slight decrease of linoleic, palmitic and stearic acids, thus improving oil quality. The results point out both the influence of the soil and the positive effect of sodium and salt stress and of the leaching fraction on the food quality of
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EFFECTS OF STORAGE PERIODS AND METHODS OF OVERCOMING DORMANCY IN SEEDS OF PASSIFLORA
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Telma Miranda dos Santos
2012-07-01
Full Text Available The aim of this work was to evaluate the effects of storage period and treatement with hot water at 50ºC or scarification on dormancy break down on Passiflora mucronata seeds. The storage periods were 0, 1, 4 and 12 months. The seeds were sown onto Germitest paper roll and incubated in a germination chamber under 20ºC/8h-30ºC/16h alternate temperature, at 16-h photoperiod (fluorescent light at 32 mol m-2 s-1 irradiance. The percent germination was evaluated, and the seeds germinated on moistened Germitest paper rolls in distilled water at a ratio of two and a half times the paper weight. The seeds were transferred to a germination chamber with alternating temperatures of 20-30º C and photoperiod of 16 h until the end of the experiment at 31 days. The experiment was analyzed as completely randomized designed with four replications, in which each plot was constituted by 50 seeds. The storage periods had significant effect on the variable studied, where the higher germination was obtained at freshly harvested seeds. At the first month of evaluation the germination decreased. After 4 and 12 months of storage, no germination was detected. The treatment with hot water at 50º or scarification favored the germination of the Passiflora seeds stored by one and four months, however even with the stimulus of the treatments, the values of final germination were low. The treatments were not efficient to stimulate the seed germination stored by 12 months.
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Base catalyzed transesterification of sunflower oil biodiesel | Ahmad ...
African Journals Online (AJOL)
In this study, sunflower oil was investigated for biodiesel production. Sunflower is one of the leading oil seed crop, cultivated for the production of oil in the world. It has also been considered as an important crop for biodiesel production. Seeds for biodiesel production were procured from local farmers of Attock and ...
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Charlet, Laurence D; Knodel, Janet J
2003-06-01
The sunflower beetle, Zygogramma exclamationis (F.), is the major defoliating pest of sunflower (Helianthus annuus L.). Planting date was evaluated as a potential management tool in a variety of production regions throughout North Dakota from 1997 to 1999, for its impact on sunflower beetle population density of both adults and larvae, defoliation caused by both feeding stages, seed yield, oil content, and larval parasitism in cultivated sunflower. Results from this 3-yr study revealed that sunflower beetle adult and larval populations decreased as planting date was delayed. Delayed planting also reduced defoliation from adult and larval feeding, which is consistent with the lower numbers of the beetles present in the later seeded plots. Even a planting delay of only 1 wk was sufficient to significantly reduce feeding damage to the sunflower plant. Yield reduction caused by leaf destruction of the sunflower beetle adults and larvae was clearly evident in the first year of the study. The other component of sunflower yield, oil content, did not appear to be influenced by beetle feeding. The tachinid parasitoid, Myiopharus macellus (Rheinhard), appeared to be a significant mortality factor of sunflower beetle larvae at most locations regardless of the dates of planting, and was able to attack and parasitize the beetle at various larval densities. The results of this investigation showed the potential of delayed planting date as an effective integrated pest management tactic to reduce sunflower beetle adults, larvae, and their resulting defoliation. In addition, altering planting dates was compatible with biological control of the beetle, because delaying the planting date did not reduce the effectiveness of the parasitic fly, M. macellus, which attacks the sunflower beetle larvae.
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Directory of Open Access Journals (Sweden)
H. Hadi
2016-05-01
Full Text Available Seedling characteristics of different sunflower (Helianthus annus L. cultivars under drought stress and inoculation with the Azospirillum lipoferum in a spilt-factorial layout based on randomized complete block design with three replications were evaluated. Treatments included dehydration stress (seed produced on maternal plants which irrigated after 60 (desirable irrigation, 120 (medium stress, 180 mm (severe stress evaporation from evaporation pan class A, different sunflower cultivars (Lakomka, Master, Favorite, Soor and Armavirosky and inoculation with bacteria (Azospirillum lipoferum and control. Bacteria allocated in the main plots and seeds which derived from dehydration stress conditions and different cultivars were allocated in sub plots as a factorial layout. Results showed that the time of seedling emergence, seedling vigor index, leaf petiole, stem and seedling dry weight were increased 14, 44, 30, 31, 22 and 27 percent by inoculating with bacteria, respectively. The percent of Seedling emergence of seeds derived from medium stress 48 percent was more than optimal irrigation conditions. Final appearance, speed of emergence, emergence index, dry weight and stamina seedling resulting from severe stress conditions were decreased compared with optimal irrigation. Seedling emergence of seeds derived from medium stress which inoculated with bacteria increased by 9 percent. Emergence speed index, appearance, stamina and seedling dry weights of seeds which inoculated with bacteria increased at medium and sever water stress. With consideration of the effect of dehydration stress on germination and seedling emergence, seed inoculation with bacteria improved seedling emergence and seedling vigor of seeds derived from dehydration stress conditions.
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Cao, Dechang; Baskin, Carol C.; Baskin, Jerry M.; Yang, Fan; Huang, Zhenying
2012-01-01
Background and Aims Differences in dormancy and germination requirements have been documented in heteromorphic seeds of many species, but it is unknown how this difference contributes to maintenance and regeneration of populations. The primary aim of this study was to compare the seed bank dynamics, including dormancy cycling, of the two seed morphs (black and brown) of the cold desert halophyte Suaeda corniculata and, if differences were found, to determine their influence on regeneration of the species. Method Seeds of the two seed morphs were buried, exhumed and tested monthly for 24 months over a range of temperatures and salinities, and germination recovery and viability were determined after exposure to salinity and water stress. Seedling emergence and dynamics of the soil seed bank were also investigated for the two morphs. Key Results Black seeds had an annual dormancy/non-dormancy cycle, while brown seeds, which were non-dormant at maturity, remained non-dormant. Black seeds also exhibited an annual cycle in sensitivity of germination to salinity. Seedlings derived from black seeds emerged in July and August and those from brown seeds in May. Seedlings were recruited from 2·6 % of the black seeds and from 2·8 % of the brown seeds in the soil, and only 0·5 % and 0·4 % of the total number of black and brown seeds in the soil, respectively, gave rise to seedlings that survived to produce seeds. Salinity and water stress induced dormancy in black seeds and decreased viability of brown seeds. Brown seeds formed only a transient soil seed bank and black seeds a persistent seed bank. Conclusions The presence of a dormancy cycle in black but not in brown seeds of S. corniculata and differences in germination requirements of the two morphs cause them to differ in their germination dynamics. The study contributes to our limited knowledge of dormancy cycling and seed bank formation in species producing heteromorphic seeds. PMID:22975287
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First stage of bio-jet fuel production: non-food sunflower oil extraction using cold press method
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Xianhui Zhao
2014-06-01
Full Text Available As a result of concerning petroleum price increasing and environmental impact, more attention is attracted to renewable resources for transportation fuels. Because not conflict with human and animal food resources, non-food vegetable oils are promising sources for developing bio-jet fuels. Extracting vegetable oil from oilseeds is the first critical step in the pathway of bio-jet fuel production. When sunflower seeds are de-hulled, there are always about 5%–15% broken seed kernels (fine meat particles left over as residual wastes with oil content up to 48%. However, the oil extracted from these sunflower seed residues is non-edible due to its quality not meeting food standards. Genetically modified sunflower grown on margin lands has been identified one of sustainable biofuel sources since it doesn't compete to arable land uses. Sunflower oils extraction from non-food sunflower seeds, sunflower meats, and fine sunflower meats (seed de-hulling residue was carried out using a cold press method in this study. Characterization of the sunflower oils produced was performed. The effect of cold press rotary frequency on oil recovery and quality was discussed. The results show that higher oil recovery was obtained at lower rotary frequencies. The highest oil recovery for sunflower seeds, sunflower meats, and fine sunflower meats in the tests were 75.67%, 89.74% and 83.19% respectively. The cold press operating conditions had minor influence on the sunflower oil quality. Sunflower meat oils produced at 15 Hz were preliminarily upgraded and distilled. The properties of the upgraded sunflower oils were improved. Though further study is needed for the improvement of processing cost and oil recovery, cold press has shown promising to extract oil from non-food sunflower seeds for future bio-jet fuel production.
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Atmospheric non-thermal argon-oxygen plasma for sunflower seedling growth improvement
Matra, Khanit
2018-01-01
Seedling growth enhancement of sunflower seeds by DC atmospheric non-thermal Ar-O2 plasma has been proposed. The plasma reactor was simply designed by the composition of multi-pin electrodes bonded on a solderable printed circuit board (PCB) anode. A stable plasma was exhibited in the non-periodical self-pulsing discharge mode during the seed treatment. The experimental results showed that non-thermal plasma treatment had a significant positive effect on the sunflower seeds. Ar-O2 mixed gas ratio, treatment time and power source voltage are the important parameters affecting growth stimulation of sunflower sprouts. In this research, the sunflower seeds treated with 3:3 liters per minute (LPM) of Ar-O2 plasma at a source voltage of 8 kV for 1 min showed the best results in stimulating the seedling growth. The results in this case showed that the dry weight and average shoot length of the sunflower sprouts were 1.79 and 2.69 times higher and heavier than those of the untreated seeds, respectively.
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Directory of Open Access Journals (Sweden)
Zhang Dale
2017-12-01
Full Text Available The seed dormancy characteristic is regarded as one of the most critical factors for pre-harvest sprouting (PHS resistance. As a wild wheat relative species, Aegilops tauschii is a potential genetic resource for improving common wheat. In this study, an advanced backcross population (201 strains containing only Ae. tauschii segments was developed by means of synthetic octaploid wheat (hexaploid wheat Zhoumai 18 × Ae. tauschii T093. Subsequently, seed dormancy rate (Dor in the advanced backcross population was evaluated on the day 3, 5 and 7, in which 2 major QTLs (QDor-2D and QDor-3D were observed on chromosomes 2D and 3D with phenotypic variance explained values (PVEs of 10.25 and 20.40%, respectively. Further investigation revealed significant correlation between QDor-3D and Tamyb10 gene, while no association was found between the former and TaVp1 gene, implying that QDor-3D site could be of closer position to Tamyb10. The obtained quantitative trait locus sites (QTLs in this work could be applied to develop wheat cultivars with PHS resistance.
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Petr Smýkal
2017-04-01
Full Text Available The origin of the agriculture was one of the turning points in human history, and a central part of this was the evolution of new plant forms, domesticated crops. Seed dispersal and germination are two key traits which have been selected to facilitate cultivation and harvesting of crops. The objective of this study was to analyze anatomical structure of seed coat and pod, identify metabolic compounds associated with water-impermeable seed coat and differentially expressed genes involved in pea seed dormancy and pod dehiscence. Comparative anatomical, metabolomics, and transcriptomic analyses were carried out on wild dormant, dehiscent Pisum elatius (JI64, VIR320 and cultivated, indehiscent Pisum sativum non-dormant (JI92, Cameor and recombinant inbred lines (RILs. Considerable differences were found in texture of testa surface, length of macrosclereids, and seed coat thickness. Histochemical and biochemical analyses indicated genotype related variation in composition and heterogeneity of seed coat cell walls within macrosclereids. Liquid chromatography–electrospray ionization/mass spectrometry and Laser desorption/ionization–mass spectrometry of separated seed coats revealed significantly higher contents of proanthocyanidins (dimer and trimer of gallocatechin, quercetin, and myricetin rhamnosides and hydroxylated fatty acids in dormant compared to non-dormant genotypes. Bulk Segregant Analysis coupled to high throughput RNA sequencing resulted in identification of 770 and 148 differentially expressed genes between dormant and non-dormant seeds or dehiscent and indehiscent pods, respectively. The expression of 14 selected dormancy-related genes was studied by qRT-PCR. Of these, expression pattern of four genes: porin (MACE-S082, peroxisomal membrane PEX14-like protein (MACE-S108, 4-coumarate CoA ligase (MACE-S131, and UDP-glucosyl transferase (MACE-S139 was in agreement in all four genotypes with Massive analysis of cDNA Ends (MACE data. In
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Energy Technology Data Exchange (ETDEWEB)
Lindemann, K [Landwirtschaftsschule, Alzey (Germany, F.R.); Hunger, A [Landes-, Lehr- und Forschungsanstalt fuer Landwirtschaft, Weinbau und Gartenbau, Neustadt (Germany, F.R.); Weickel, J [Landespflanzenschutzamt Rheinland-Pfalz, Mainz (Germany, F.R.)
1988-01-01
Sunflowers are cultivated throughout the world, primarily for oil extraction but also as a birdseed, for eating, or for backing. Although some attempts have been made, they are hardly ever used as green fodder. Sunflowers grown for oil extraction usually have thin-shelled, black seeds. They have an oil fraction of 40 to 50% and a protein fraction of more than 20%. Sunflowers for other uses have large seeds with thick, striped shells. Their oil fraction is between 25 and 30%. (orig.).
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Physical properties of sunflower grains after drying
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Paulo Carteri Coradi
2015-12-01
Full Text Available The knowledge of the physical properties of the grains is important for the optimization of post-harvest operations. This study aimed to evaluate the effects of convective drying with different air temperatures (45, 55, 65 and 75 °C the physical properties of sunflower seeds. The drying sunflower grains was performed in convection oven with forced air. In natural conditions, samples of 5 kg of pellets were used for each repetition drying. During the drying process, the grains samples were weighed periodically until they reach 10% (wet basis, w.b., then were subjected to evaluations of physical properties. According to the results it was observed that the porosity, apparent density, thousand kernel weight to the drag coefficient, roundness, sphericity and width of sunflower seed did not change with increasing temperature drying air. It was concluded that the drying air temperatures of 45 °C and 55 retained the initial physical characteristics of sunflower seeds. The temperature of the drying air of 75 °C had greater influence on changes in volumetric shrinkage of the grains.
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Alhadi Fatima A.
2012-04-01
Full Text Available Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensure their germination under favorable environmental conditions. Most plant seeds have complex process of germination, including water, oxygen, temperature availability, genome-wide gene expression, signal transduction, hormones stimulations, inhibitors removal and catalytic protein synthesis. In addition, influences of seeds nutrient values such as, protein, lipids, sugars and free amino acids have a special importance. Regarding, seeds free amino acids. Discussion of these individual factors needs to be put in context of their role in germination processes. Regarding, free amino acids seed storage, there is limited information about their relevant functions in activation and/or deactivation of required metabolic mechanisms and interactive compounds involved in this process in commercial plant cultivars. Therefore, current study was aimed to determine the probable influence of free amino acid compositions of seeds on germination process of two different (Punica granatum L. pomegranate cultivars including wild type Automi cultivar and edible Khazemi cultivar. In particular, we focused on the impact of amino acids contents variations on germination process and associated AAs compositional changes during various stages of germination and seedlings establishment. Amino acid analysis using HPLC detected all the essential and non-essential amino acids in the raw seeds of the studied cultivars, Automi and Khazemi along with AAs compositional changes occurred during different stages of seed germination. These AAs have been extensively analyzed in the context of their role in dormancy breaking capacities in plants species. Automi raw seeds are rich in Phe, that, is strongly related to ABA synthesis and hence might be responsible for the dormancy of Automi seeds, Khazemi raw seeds have sufficient levels of Arg, Glu and Met that have been reported to enhance
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Jaganathan, G K; Wu, G-R; Han, Y-Y; Liu, B L
2017-01-01
Physical dormancy occurs in all three subfamilies of Fabaceae, namely Mimosoideae, Papilionoideae and Caesalpinioideae, making it one of the largest plant families in terms of number of species with physical dormancy. However, little is known about the water gap structure and germination ecology of species in Caesalpinioideae. Freshly collected seeds of Delonix regia (Caesalpinioideae) did not imbibe water, thus they had physical dormancy. Both dry heat and wet heat were effective in breaking dormancy, however, longer duration was required at 80 °C and shorter duration at 90 °C. Seeds buried in the field for 2 years germinated to 21% and 42% after the first and second summer, respectively, compared with 3% germination in seeds at the time of maturity. Seeds incubated at 15/60 °C in the laboratory (mimicking summer conditions) for 3 months supported this conclusion, as dormancy was relieved in 18% and 24% of seeds stored dry and watered intermediately, respectively. All the dormancy breaking treatments resulted in lifting of palisade layers in the lens region to form a circular lid-like opening, i.e. water gap (Type II simple). Blocking experiments confirmed that water entered only through the lens and no secondary water entry point was observed. No apparent changes in morphology/anatomy of the hilum region were noted in dormant and non-dormant (water permeable) seeds. These results suggest that summer temperatures could open the lens in a proportion of seeds every year and that germination occurs during the subsequent wet season in the tropics. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.
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The pleiotropic effects of the seed germination inhibitor germostatin.
Ye, Yajin; Zhao, Yang
2016-01-01
Seed dormancy and germination are the most important adaptive traits of seed plants, which control the germination in a proper space and time. Internal genetic factors together with environmental cues govern seed dormancy and germination. Abscisic acid (ABA), a key phytohormone induces seed dormancy and inhibits seed germination through its molecular genetic signaling network responding the seed inherent physiological and environmental factors. Recently, auxin has been shown to be another phytohormone that induces seed dormancy. We have recently shown that germonstatin (GS), a small synthetic molecule identified by high through-put chemical genetic screenings, inhibits seed germination through up-regulating auxin signaling and inducing auxin biosynthesis. GERMOSTATIN RESISTANCE LOCUS 1 (GSR1) encodes a plant homeodomain (PHD) finger protein and is responsible for GS seed germination inhibition. Its knockdown mutant gsr1 displays decreased dormancy. In this report, we show that GS is not an ABA analog and provided 2 other GS-resistant mutants related to the chemical's function in seed germination inhibition other than gsr1, suggesting that GS may have pleiotropic effects through targeting different pathway governing seed germination.
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Kabutey, A.; Herak, D.; Sigalingging, R.; Demirel, C.
2018-02-01
The deformation energy (J) and percentage oil yield (%) of sunflower bulk seeds under the influence of heat treatment temperatures and heating time were examined in compression test using the universal compression testing machine and vessel diameter of 60 mm with a plunger. The heat treatment temperatures were between 40 and 100 °C and the heating time at specific temperatures of 40 and 100 °C ranged from 15 to 75 minutes. The bulk sunflower seeds were measured at a pressing height of 60 mm and pressed at a maximum force of 100 kN and speed of 5 mm/min. Based on the compression results, the deformation energy and oil yield increased along with increasing heat treatment temperatures. The results were statistically significant (p 0.05).
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Mureşan, V.
2013-01-01
Full Text Available Sunflower "halva" is a popular and widely enjoyed confectionery product specific to the countries of Eastern Europe. Conventional halva has historically been produced from sesame seeds in the Middle East and Northern Africa. However, in the production of halva in Eastern Europe, sesame seeds have been largely replaced by sunflower seeds, due to the high availability of sunflower in this region and the comparable taste of the final product. Due to the importance of the cost of raw materials in the food industry, utilization of sunflower seeds in halva production may be of great interest worldwide because it offers the possibility of significantly lowering production costs. Nevertheless, oil separation and storage techniques must be perfected if sunflower halva is to fulfill its promise of becoming a cost effective alternative to sesame seed halva on a worldwide scale. The aims of this review are firstly, to describe the current state of sunflower halva technology, secondly, to isolate the main problems affecting the quality of the final product, and thirdly, to suggest areas of further research necessary to move sunflower halva production closer to reaching its full potential on the world market.
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Effect of magnetic field on seed germination and seedling growth of sunflower
Matwijczuk, A.; Kornarzyński, K.; Pietruszewski, S.
2012-07-01
The impact of a variable magnetic field, magnetically treated water and a combination of both these factors on the germination of seeds and the final mass at the initial stage of growth sunflower plants was presented. Investigations were carried out in pots filled with sand, tin an air-conditioned plant house with no access to daylight using fluorescent light as illumination. A statistical significance positive impact was achieved for the samples subjected to the interaction of both stimulating factors simultaneously, the magnetic field and the impact of treated water several times on the speed of seed germination and final plant mass. Negative impacts were obtained for the majority of the test cases, for the magnetically treated water, the short duration of activity of the magnetic field and for the connection of the magnetic field and low-flow times.
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Breaking Dormancy In Gmelina arborea Roxb. Through Treatment ...
African Journals Online (AJOL)
Seeds of Gmelina arborea Roxb. were subjected to different treatment [chemical scarification with concentrated sulphuric acid (H2S04), potasium nitrate (KNO3), potasium nitrite (KNO2) and alternating temperature regimes] to ascertain the best treatment for terminating dormancy in the seeds. Initial viability and germination ...
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International Nuclear Information System (INIS)
Rasheed, A.; Hameed, A.; Khan, M.A.; Gul, B.
2015-01-01
Salsola drummondii Ulbr. is a perennial halophyte found in salt deserts of southern Balochistan, Pakistan. Experiments were conducted to study the effects of salinity (0, 200, 400, 600, 800 and 1000 mM NaCl), thermoperiod (10/20, 15/25, 20/30 and 25/35 degree C), light (12-h photoperiod and dark) and dormancy regulating chemicals (DRCs) on germination, recovery and viability of the seeds of S. drummondii. Seeds of S. drummondii germinated quickly in distilled water at different temperature regimes and increases in salinity decreased seed germination. Interestingly, few seeds could even germinate in 1000 mM NaCl treatment, which is about twice as high as seawater salinity. Seeds were partially photoblastic and showed relatively higher germination under 12-h photoperiod than in dark. Seeds showed poor recovery of germination from salinity and particularly when germinated in dark. Germination inhibition at high salinity (800 mM NaCl) under 12-h photoperiod was partially alleviated by the exogenous application of different DRCs, particularly fusicoccin. Moreover, all the DRCs, except GA4+7, ameliorated germination of salt stressed seeds under complete darkness and GA4 and fusicoccin were most effective. Our study shows that seeds of S. drummondii are highly tolerant to salinity and variation in temperature but partially photoblastic nature indicate that seeds will not germinate if buried under the soil. Seed germination under saline conditions can be improved by the use of DRCs particularly by application of fusicoccin. (author)
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Ahmad BEIKMOHAMMADI
2012-05-01
Full Text Available The present study was conducted in order to evaluate the existence and type of the dormancy and effects of different dormancy breaking treatments on seed germination of Colutea buhsei Boiss. (Fabaceae as one of the Iran native plants, arid-land and ornamental shrub with ability of usage in the urban landscape design. The experiment was performed with 15 treatments and 3 replications in a completely randomized design. Seeds were subjected to different treatments including various levels of GA3, concentrated (98% H2SO4, cold stratification (CS, soaking with tab water, floating in hot water (100�C followed by continual cooling for 24 hr in the same water and combined treatments. Afterwards seeds were sown in laboratory conditions to determine the factors� effects on germination percentage (GP, germination rate (GR, root and shoot length of Colutea bohsei seeds. All of these treatments, except for GA3 (250 and 500 ppm, increased the percentage and rate of the seed germination. Maximum germination percentage (66.25% and rate (14.9 seeds per day in 7 days was obtained at concentrated (98% H2SO4 (15 min. Maximum root and shoot length was observed at concentrated (98% H2SO4 (15 min plus GA3 (100 ppm, 24 hr. Use of GA3 (100 ppm in 24 hr after H2SO4 increased the germination rate and shoot length but this additive effect was not significant.
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Jocely Andreuccetti Maeda
1985-01-01
Full Text Available A manutenção da viabilidade de sementes por períodos mais ou menos longos está bastante relacionada com as condições em que elas são armazenadas. Temperatura e teor de umidade estão entre os fatores que mais afetam sua longevidade. O objetivo deste trabalho é o estudo da viabilidade e dormência de uva do cultivar Patrícia, armazenada durante 24 meses em dois tipos de recipientes - em vidro hermético e saco de papel - a temperaturas de 10, 20 e 30°C, com dois diferentes teores iniciais de umidade. A porcentagem de sementes dormentes e viáveis foi determinada bimestralmente durante os primeiros 12 meses, e semestralmente nos períodos mais longos. O armazenamento não quebrou a dormência das sementes de uva em nenhuma das condições estudadas. Enquanto as sementes frescas mostraram melhor conservação a 10°C quando embaladas em vidro hermético, sementes secas se conservaram melhor a 20°C. Em saco de papel, foram poucas as diferenças encontradas entre os tratamentos, a não ser nos períodos finais do armazenamento, quando 20°C se mostrou a pior temperatura de conservação. Dessa maneira, a dormência não foi alterada pelo armazenamento, nas condições estudadas, e a viabilidade foi bastante afetada tanto pelo tipo de embalagem como pela temperatura de armazenamento.Longevity of seeds is affected by the storage conditions, being temperature and seed moisture content the major factors to keep seeds viable. Experiments described here are concerned to the study of dormancy ant viability of seeds of grape cv. Patrícia, stored with two different moisture contents, either in moisture proof containers or paper bags, at temperaturss of 10°C, 20°C and 30°C, for 24 months. Samples were taken every two months during the first 12 months and at 6 months intervals in the second year, to determine seed viability and dormancy level. Storage, in the studied conditions, did not alter dormancy levei of the seeds. When stored in hermetical
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Relationship between weed dormancy and herbicide rotations: implications in resistance evolution.
Darmency, Henri; Colbach, Nathalie; Le Corre, Valérie
2017-10-01
It is suggested that selection for late germinating seed cohorts is significantly associated with herbicide resistance in some cropping systems. In turn, it is conceivable that rotating herbicide modes of action selects for populations with mutations for increased secondary dormancy, thus partially overcoming the delaying effect of rotation on resistance evolution. Modified seed dormancy could affect management strategies - like herbicide rotation - that are used to prevent or control herbicide resistance. Here, we review the literature for data on seed dormancy and germination dynamics of herbicide-resistant versus susceptible plants. Few studies use plant material with similar genetic backgrounds, so there are few really comparative data. Increased dormancy and delayed germination may co-occur with resistance to ACCase inhibitors, but there is no clear-cut link with resistance to other herbicide classes. Population shifts are due in part to pleiotropic effects of the resistance genes, but interaction with the cropping system is also possible. We provide an example of a model simulation that accounts for genetic diversity in the dormancy trait, and subsequent consequences for various cropping systems. We strongly recommend adding more accurate and detailed mechanistic modelling to the current tools used today to predict the efficiency of prevention and management of herbicide resistance. These models should be validated through long-term experimental designs including mono-herbicide versus chemical rotation in the field. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
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Dragee product based on sunflower
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Pajin Biljana S.
2003-01-01
Full Text Available The sunflower kernel is rich in valuable nutritive compounds so it is suitable as a raw material for production of confectionery products. In this paper we evaluated the technological characteristics of the confectionery sunflower kernel with the aim of obtaining dragee products, and determining the final product quality and shelf life. The dragee product was obtained by panning sunflower kernel with savory powder mixture of spices in a dragee pan. The used sunflower seed has an even distribution of linear size and satisfactory dehulling characteristics. The savoury dragee product was in excellent category of sensory quality and showed stable colour and good shelf life in the period of three months.
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Effect of different treatments on breaking dormancy of Teucrium polium
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alireza koochaki
2009-06-01
Full Text Available In order to evaluate effects of different treatments on breaking dormancy of Teucrium polium, an experiment was conducted with 3 replications in a completely randomized design. Seeds were subjected to different treatments including various levels of GA3, H2SO4, soaking with water and chilling. Germination of Teucrium polium increased with different concentrations of GA3. Percentage germination Maximum and rate was obtained at concentrations of 250, 1500 ppm (72h GA3 and combination of GA3 (1500ppm and chilling (5 ºC for a period of 14 days. GA3 (500ppm increased germination percentage but not germination rate. Soaking with water broke dormancy and induced 32% seed germination of Teucrium polium, but H2SO4, freezing (-10 ºC and combination of both treatments had no effect on dormancy.
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On the language and physiology of dormancy and quiescence in plants.
Considine, Michael J; Considine, John A
2016-05-01
The language of dormancy is rich and poetic, as researchers spanning disciplines and decades have attempted to understand the spell that entranced 'Sleeping Beauty', and how she was gently awoken. The misleading use of 'dormancy', applied to annual axillary buds, for example, has confounded progress. Language is increasingly important as genetic and genomic approaches become more accessible to species of agricultural and ecological importance. Here we examine how terminology has been applied to different eco-physiological states in plants, and with pertinent reference to quiescent states described in other domains of life, in order to place plant quiescence and dormancy in a more complete context than previously described. The physiological consensus defines latency or quiescence as opportunistic avoidance states, where growth resumes in favourable conditions. In contrast, the dormant state in higher plants is entrained in the life history of the organism. Competence to resume growth requires quantitative and specific conditioning. This definition applies only to the embryo of seeds and specialized meristems in higher plants; however, mechanistic control of dormancy extends to mobile signals from peripheral tissues and organs, such as the endosperm of seed or subtending leaf of buds. The distinction between dormancy, quiescence, and stress-hardiness remains poorly delineated, most particularly in buds of winter perennials, which comprise multiple meristems of differing organogenic states. Studies in seeds have shown that dormancy is not a monogenic trait, and limited study has thus far failed to canalize dormancy as seen in seeds and buds. We argue that a common language, based on physiology, is central to enable further dissection of the quiescent and dormant states in plants. We direct the topic largely to woody species showing a single cycle of growth and reproduction per year, as these bear the majority of global timber, fruit, and nut production, as well being
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Morsy, T A; Kholif, S M; Kholif, A E; Matloup, O H; Salem, A Z M; Elella, A Abu
2015-08-01
This study aimed to investigate the effect of sunflower seeds, either as whole or as oil, on rumen fermentation, milk production, milk composition and fatty acids profile in dairy goats. Fifteen lactating Damascus goats were divided randomly into three groups (n = 5) fed a basal diet of concentrate feed mixture and fresh Trifolium alexandrinum at 50:50 on dry matter basis (Control) in addition to 50 g/head/d sunflower seeds whole (SS) or 20 mL/head/d sunflower seeds oil (SO) in a complete randomized design. Milk was sampled every two weeks during 90 days of experimental period for chemical analysis and rumen was sampled at 30, 60, and 90 days of the experiment for ruminal pH, volatile fatty acids (tVFA), and ammonia-N determination. Addition of SO decreased (p = 0.017) ruminal pH, whereas SO and SS increased tVFA (pcontent (p = 0.002). Moreover, SO increased milk lactose content (p = 0.048) and feed efficiency (p = 0.046) compared to Control. Both of SS and SO increased (pcontent specially conjugated linolenic acid (CLA) vs Control. Addition of SS and SO increased (p = 0. 021) C18:3N3 fatty acid compared to Control diet. Data suggested that addition of either SS or SO to lactating goats ration had beneficial effects on milk yield and milk composition with enhancing milk content of healthy fatty acids (CLA and omega 3), without detrimental effects on animal performance.
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Directory of Open Access Journals (Sweden)
Julien De Giorgi
2015-12-01
Full Text Available Cuticular layers and seeds are prominent plant adaptations to terrestrial life that appeared early and late during plant evolution, respectively. The cuticle is a waterproof film covering plant aerial organs preventing excessive water loss and protecting against biotic and abiotic stresses. Cutin, consisting of crosslinked fatty acid monomers, is the most abundant and studied cuticular component. Seeds are dry, metabolically inert structures promoting plant dispersal by keeping the plant embryo in an arrested protected state. In Arabidopsis thaliana seeds, the embryo is surrounded by a single cell endosperm layer itself surrounded by a seed coat layer, the testa. Whole genome analyses lead us to identify cutin biosynthesis genes as regulatory targets of the phytohormones gibberellins (GA and abscisic acid (ABA signaling pathways that control seed germination. Cutin-containing layers are present in seed coats of numerous species, including Arabidopsis, where they regulate permeability to outer compounds. However, the role of cutin in mature seed physiology and germination remains poorly understood. Here we identify in mature seeds a thick cuticular film covering the entire outer surface of the endosperm. This seed cuticle is defective in cutin-deficient bodyguard1 seeds, which is associated with alterations in endospermic permeability. Furthermore, mutants affected in cutin biosynthesis display low seed dormancy and viability levels, which correlates with higher levels of seed lipid oxidative stress. Upon seed imbibition cutin biosynthesis genes are essential to prevent endosperm cellular expansion and testa rupture in response to low GA synthesis. Taken together, our findings suggest that in the course of land plant evolution cuticular structures were co-opted to achieve key physiological seed properties.
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Some Soil Characters and Qualitative Traits of Sunflower Seeds to Different Nutritional Regimes
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F Soleymani
2018-05-01
Full Text Available Introduction To achieve the high economic yield in crops, supplying enough nutrients for plants is important, that much of it, supplied by chemical fertilizers. But excessive use of chemical fertilizers led to environmental problems that these negative effects have caused attention to healthy and ecological sustainable farming systems. One solution to reduce dependence on chemical fertilizers is application of organic and biological products for plant nutrition. Bio-fertilizers are made from one or more species of beneficial microorganisms with preservatives and or their products. In addition, vermicompost is an organic fertilizer and mixed of very active biological bacteria, enzymes, plant residues, manure and earthworm capsule which leads to continued organic matter decomposition and development of microbial and enzymatic activities in soil. Several experiments have shown that the using of biological and organic fertilizers improve growth and quality of products. Materials and Methods To investigate the effect of various nutritional regimes on seed quality characteristics of sunflower (Euroflour cv. and some soil characters, an experiment was carried out as a randomized complete block design with 3 replications in 2015 at the Agricultural Faculty of Bu-Ali Sina University.Treatments included no biological or chemical fertilizer application, 100% of the recommended NP fertilizers (250 kg urea per hectare, 50 kg triple superphosphate per hectare, ½ recomended NP fertilizers, vermicompost (15 ton per hectare mixed with soil, phosphonitrokara (including Bacillus coagulans, Azotobacter chroococcum, Azospirillum lipoferum, 110 ml to inoculate 10 kg seeds, biosulfur (including Thiobacillus,mix 6 kg of fertilizer with 300 kg sulphur for 1 hectare, vermicompost+ phosphonitrokara, vermicompost+ biosulfur, vermicompost+½ NP fertilizers, phosphonitrokara+½ NP fertilizers, biosulfur+½ NP fertilizers, vermicompost+ phosphonitrokara+½ NP fertilizers
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Expression of modified tocopherol content and profile in sunflower tissues.
Del Moral, Lidia; Fernández-Martínez, José M; Pérez-Vich, Begoña; Velasco, Leonardo
2012-01-30
Alpha-tocopherol is the predominant tocopherol form in sunflower seeds. Sunflower lines that accumulate increased levels of beta-, gamma- and delta-tocopherol in seeds as well as lines with reduced and increased total seed tocopherol content have been developed. The objective of this research was to evaluate whether the modified tocopherol levels are expressed in plant tissues other than seeds. Lines with increased levels of beta-, gamma- and delta-tocopherol in seeds also possessed increased levels of these tocopherols in leaves, roots and pollen. Correlation coefficients for the proportion of individual tocopherols in different plant tissues were significantly positive in all cases, ranging from 0.68 to 0.97. A line with reduced tocopherol content in seeds also showed reduced content in roots and pollen. Genetic modifications producing altered seed tocopherol profiles in sunflower are also expressed in leaves, roots and pollen. Reduced total seed tocopherol content is mainly expressed at the root and pollen level. The expression of tocopherol mutations in other plant tissues will enable further studies on the physiological role of tocopherols and could be of interest for early selection for these traits in breeding programmes. Copyright © 2011 Society of Chemical Industry.
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Aznar-Moreno, Jose A; Venegas-Calerón, Mónica; Martínez-Force, Enrique; Garcés, Rafael; Salas, Joaquín J
2016-08-01
The kinetics of acyl-ACP thioesterases from sunflower importantly changed when endogenous ACPs were used. Sunflower FatB was much more specific towards saturated acyl-ACPs when assayed with them. Acyl carrier proteins (ACPs) are small (~9 kDa), soluble, acidic proteins involved in fatty acid synthesis in plants and bacteria. ACPs bind to fatty acids through a thioester bond, generating the acyl-ACP lipoproteins that are substrates for fatty acid synthase (FAS) complexes, and that are required for fatty acid chain elongation, acting as important intermediates in de novo fatty acid synthesis in plants. Plants, usually express several ACP isoforms with distinct functionalities. We report here the cloning of three ACPs from developing sunflower seeds: HaACP1, HaACP2, and HaACP3. These proteins were plastidial ACPs expressed strongly in seeds, and as such they are probably involved in the synthesis of sunflower oil. The recombinant sunflower ACPs were expressed in bacteria but they were lethal to the prokaryote host. Thus, they were finally produced using the GST gene fusion system, which allowed the apo-enzyme to be produced and later activated to the holo form. Radiolabelled acyl-ACPs from the newly cloned holo-ACP forms were also synthesized and used to characterize the activity of recombinant sunflower FatA and FatB thioesterases, important enzymes in plant fatty acids synthesis. The activity of these enzymes changed significantly when the endogenous ACPs were used. Thus, FatA importantly increased its activity levels, whereas FatB displayed a different specificity profile, with much high activity levels towards saturated acyl-CoA derivatives. All these data pointed to an important influence of the ACP moieties on the activity of enzymes involved in lipid synthesis.
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Physico-chemical attributes of seed oil from drought stressed sunflower (Helianthus annuus L. plants
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Anwar, Farooq
2009-12-01
Full Text Available The effects of water deficit conditions on the qualitative and quantitative characteristics of sunflower seed and seed oils were assessed. Two sunflower cultivars (Gulshan-98 and Suncross were sown in the field. The water stress treatment was applied at the vegetative or the reproductive stage. Analysis of the sunflower seed showed that the oil content decreased (a decline of 10.52% relative to the control significantly (p ≤ 0.05 due to water stress when imposed at either of the growth stages. Both of the sunflower cultivars studied showed differential responses to water stress with respect to oil oleic and linoleic acid contents. A significant negative correlation in oil oleic and linoleic acid was observed in cv. Gulshan-98 under water deficit conditions as compared to Suncross in which no such effect of water stress on oleic and linoleic acid was observed. Water deficit conditions caused a reduction in linolenic acid in Gulshan-98, whereas it remained unaffected in Suncross. The stearic acid content increased in cv. Gulshan-98 due to drought, whereas no effect due to water stress was observed on oil palmitic acid content in either sunflower cultivar. Overall, oil unsaturated fatty acids remained unchanged in the drought stressed or normally irrigated plants of both cultivars but saturated fatty acid increased in Gulshan-98. Individual (α, γ, and δ and total tocopherol contents in the seed oil increased significantly with the application of water stress in both cultivars. An assessment of the physical and chemical characteristics of the oils of both sunflower cultivars revealed that drought stress caused a marked increase in the content of un-saponifiable matter (18.75% with respect to the control and a decrease in iodine value (5.87% with respect to the control, but saponifcation value, density, specific gravity and refractive index remained unchanged.El efecto de las condiciones de déficit de agua sobre las caracter
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Footitt, S; Huang, Z; Ölcer-Footitt, H; Clay, H; Finch-Savage, W E
2018-03-23
The impact of global warming on seed dormancy loss and germination was investigated in Alliaria petiolata (garlic mustard), a common woodland/hedgerow plant in Eurasia, considered invasive in North America. Increased temperature may have serious implications, since seeds of this species germinate and emerge at low temperatures early in spring to establish and grow before canopy development of competing species. Dormancy was evaluated in seeds buried in field soils. Seedling emergence was also investigated in the field, and in a thermogradient tunnel under global warming scenarios representing predicted UK air temperatures through to 2080. Dormancy was simple, and its relief required the accumulation of low temperature chilling time. Under a global warming scenario, dormancy relief and seedling emergence declined and seed mortality increased as soil temperature increased along a thermal gradient. Seedling emergence advanced with soil temperature, peaking 8 days earlier under 2080 conditions. The results indicate that as mean temperature increases due to global warming, the chilling requirement for dormancy relief may not be fully satisfied, but seedling emergence will continue from low dormancy seeds in the population. Adaptation resulting from selection of this low dormancy proportion is likely to reduce the overall population chilling requirement. Seedling emergence is also likely to keep pace with the advancement of biological spring, enabling A. petiolata to maintain its strategy of establishment before the woodland canopy closes. However, this potential for adaptation may be countered by increased seed mortality in the seed bank as soils warm. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.
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G. Delchev
2016-12-01
Full Text Available Abstract. The research was conducted during 2012 – 2014 on pellic vertisol soil type. Under investigation were 4 sunflower hybrids (Helianthus annuus L.: hybrid Bacardy (an imitolerant hybrid by ClearField plus technology, hybrid Estiva (an imitolerant hybrid by ClearField technology, hybrid Sumico (a tribenuron-methyl tolerant hybrid by ExpessSun technology and hybrid Arizona (a hybrid by conventional technology. Factor A included the years of investigation. Factor B, herbicides and tank mixtures, included 20 rates. It includes 3 variants by ClearField plus technology, 5 variants by ClearField technology, 5 variants by ExpessSun technology and 7 variants by conventional technology. All variants are on herbicide Gardoprim plus gold 500 SC (Smetolachlor + terbuthylazine – 3.5 l/ha, which treated after sowing before emergence of the sunflower. It is found that the highest seed yield is obtained at herbicide tank mixture Pulsar plus + Stomp aqua by ClearField plus technology. Tank mixture Listego + Dash + Sharpen by ClearField technology and Express + Trend + Select super by ExpressSun technology also lead to obtaining high seed yields. The most unstable are secondary weed infested checks by the fourth technologies for sunflower growing which are treated with soil-applied herbicide Gardoprim plus gold only. Technologically the most valuable are herbicide combination Pulsar plus + Stomp aqua and herbicide Pulsar by ClearField plus technology, tank mixtures Listego + Dash + Sharpen and Listego + Dash by ClearField technology and Express + Trend + Select super and Express + Lactofol B + Select super by ExpressSun technology. Tank mixtures of herbicides Smerch, Pendigan, Wing, Raft, Pledge and Modown with Amalgerol premium by conventional technology have low estimates due to insufficient control of some weeds in sunflower crops.
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Chang Bon Choi
2016-02-01
Full Text Available This study was conducted to evaluate the effect of dietary supplementation with rice bran, flax seed, or sunflower seed to finishing native Korean cattle (Hanwoo on growth performances, carcass characteristics, fatty acid composition, free amino acid and peptide contents, and sensory evaluations of Longissimus muscle (LM. A total of 39 Hanwoo steers (average age of 22.2 mo and average body weight (BW of 552.2 kg were randomly divided into Control, rice bran (RB, flax seed (FS, or Sunflower seed (SS groups. The steers were group fed for 273 d until they reached an average age of 31.2 mo. Final BW was 768.2, 785.8, 786.2, and 789.0 kg, and average daily gain was 0.79, 0.85, 0.82, and 0.84 kg for the Control, RS, FS, and SS groups, respectively (p>0.05. Fat thickness of the FS group (19.8 mm was greater (p0.05 scores for flavor, umami, and overall palatability in sensory evaluations. In conclusion, supplementation of flax seed to diets of finishing Hanwoo steers improved sensory evaluations which might have been caused by increases in flavor related amino acids such as methionine, glutamic acid and α-AAA and peptides, anserine and carnosine, and their complex reactions.
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African Journals Online (AJOL)
UTILISATEUR
Garcinia kola seeds to six different hormonal pre-germination treatments. This consisted of ... Thus, seed dormancy in this case is not a coat- imposed .... development of the cultivation of the species. The cause .... Hormonal regulation of seed ...
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ACCELERATED AGING TEST IN DETERMINING THE VIGOUR OF SUNFLOWER SEEDS WITH AND WITHOUT PERICARP
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K. R. Ducatti
2014-09-01
Full Text Available The standard germination test alone is insufficient to attest the quality of seeds, making necessary correlation’s with vigour tests, to determine more accurately the physiological potential of a seeds lot. The accelerated aging test is an option for determine the vigour and consists in submits seeds to high temperatures and humidity, for different periods of time, has not yet standardized. The objective of this work was to analyze the efficiency of the accelerated aging test in the assessment of the effect of a lot of sunflower seed, by three periods of aging (48, 56 and 72 hours in 42 °C temperature, in seeds with and without pericarp (manually removed and relate the results with electrical conductivity test and germination first count. The experimental design was a completely randomized design and the comparison of averages made using Tukey's test at 5% probability. The results showed that standard germination, electrical conductivity and germination first count, the seeds without pericarp showed better performance. In relation to the accelerated aging, only in the period of 72 hours of aging there was no significant difference between the treatments. In this way, the appropriate period to identify differences in force between the treatments was 72 hours, which showed a positive correlation with the germination first count and electrical conductivity.
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Regulation of seed dormancy by abscisic acid and DELAY OF Germination 1
Dekkers, S.J.W.; Bentsink, L.
2015-01-01
Physiological dormancy has been described as a physiological inhibiting mechanism that prevents radicle emergence. It can be caused by the embryo (embryo dormancy) as well as by the structures that cover the embryo. One of its functions is to time plant growth and reproduction to the most optimal
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Giuffrè, Angelo Maria; Capocasale, Marco; Zappia, Clotilde; Poiana, Marco
2017-01-01
Two important problems for the food industry are oil oxidation and oil waste after frying. Sunflower seed oil is one of the vegetable oils most commonly used in the food industry. Two variables were applied to the low oleic sunflower seed oil in this work i.e. heating temperature (180-210-240°C) and time of heating (15-30-60-120 minutes), to study from the edible point of view the variations of its physico-chemical properties. After 120 minutes heating at 240°C the following was found: refractive index (1.476), free acidity (0.35%), K232 (2.87), K270 (3.71), antiradical activity (45.90% inhibition), total phenols (523 mg kg -1 ), peroxide value (17.00 meq kg -1 ), p-anisidine value (256.8) and Totox (271.7), all of which showed a constant deterioration. In relation to the use as a feedstock for bio-diesel production, after 120 minutes heating at 240℃ the following was found: acid value 0.70 mg KOH g -1 oil, iodine value 117.83 g I 2 100 g -1 oil, oil stability index 0.67 h, kinematic viscosity (at 40°C) 77.85 mm 2 s -1 , higher heating value 39.86 MJ kg -1 , density 933.34 kg/m 3 and cetane number 67.04. The parameters studied in this work were influenced, in different ways, by the applied variables. Heating temperature between 180 and 210°C and 120 min heating duration were found to be the most appropriate conditions for sunflower seed oil both from the deep frying point of view and from a subsequent use as feedstock for bio-diesel production. In light of the vegetable oils' International standards for an edible use and for a bio-diesel production, findings of this work can be used to set heating temperature and heating duration to preserve as long possible the physico-chemical properties of a low oleic sunflower seed oil for both its edible use as a fat during cooking and for its re-use after frying.
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Grbić Mihailo
2011-01-01
Full Text Available The Small-winged wingnut is a 12 to 20 metres tall, deciduous and fast growing tree with large substantial branches that spread as wide as the tree is tall. The 15 to 30 cm long winged fruit catkins, which turn brown in the autumn, are suspended below the branches. The species is not described by domestic authors in Serbia. The seed was introduced from Sofia (from the Arboretum of the Forestry University of Sofia, Bulgaria - Lesotehničeski universitet, Sofija, and subjected to classical stratification and naked stratification during the period of 1 and 2 months. Germination capacity varied among the treatments. The largest number of germinated seeds was observed in the shorter stratifications, (1 month the classical (56.5% and the naked (51.0% with no significant difference. The values of real germination of all treatments were between 69-88%. High value of RG, compared to GC, indicated that more than 40% of the seeds were empty. However, the results of the control as well as other parameters of seed germination clearly point to the fact that practically no deep embryo dormancy was observed, but the seed is recalcitrant and microbiotic. The results indicate a non-invasive character of the species in terms of reproductive potential.
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Impact of climate changes and correlations on oil fatty acids in sunflower
International Nuclear Information System (INIS)
Onemli, F.
2012-01-01
Sunflower oil is a major important vegetable oil because it is widely used in human nutrition and in many industrial productions depends on fatty acid composition. Field studies were conducted during in two years on the same soil to investigate changes of climate induced oil fatty acid composition of a traditional sunflower, and to obtain correlations among oil fatty acids. Seed oil content and twelve fatty acid percentages of sunflower oil were analyzed. Variations for years were significant for seed oil content and palmitic acid (C16:0), oleic (C18:1), linoleic (C18:2), linolenic (C18:3), miristic (C14:0) and eicosenoic acids (C20:1). Higher temperatures during seed development in 2010 resulted with 68.38 % increasing in oleic content of the traditional sunflower hybrid. The highest negative correlations (r= -0.99) were noted between oleic and linoleic acids. (author)
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Bernal, José; Martin-Hernandez, Raquel; Diego, Juan C; Nozal, María J; Gozalez-Porto, Amelia V; Bernal, José L; Higes, Mariano
2011-10-01
There is great concern about the high losses and strong depopulation of honey bee colonies in some areas of Spain. Some beekeepers have suggested that sunflower seeds treated with the insecticide fipronil could be an important factor in causing those losses. Therefore, an in-depth field study has been carried out in two regions of Spain where sunflower production is intense (Cuenca and Andalucía) and where, for some crops and varieties, fipronil has been used as seed insecticide. Samples of adult bees and pollen were analysed for bee pathogens and pesticide residues respectively. Neither fipronil residues nor its metabolites were detected in any of the samples analysed, indicating that short-term or chronic exposure of bees to fipronil and/or its metabolites can be ruled out in the apiaries surveyed. Varroa destructor and Nosema ceranae were found to be very prevalent. The combination of the two pathogens could augment the risk of colony death in infected colonies, without fipronil residues exerting a significant effect in the given field conditions. Indeed, in this study the losses observed in apiaries located close to sunflower crops were similar to those in apiaries situated in forested areas with wild vegetation. Copyright © 2011 Society of Chemical Industry.
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Ariadne Josiane Castoldi Silva
2011-03-01
Full Text Available
Erythrina crista-galli L., Fabaceae, a medium-sized N-fixing tree, is native to flooding soils of several Brazilian biomes. Its cultivation has interest for ornamental and ecological restoration purposes. Information on seed coat dormancy is conflicting and inexact, therefore the present work aimed to verify it and to define methods for its overcoming. The study was composed by two experiments, using seed lots collected in different dates. Seeds were subjected to inducing germination treatments by chemical scarification (ACS commercial sulfuric acid, d=1,84 g/cm³ and thermic scarification (hot water. Results demonstrated high germination under acid scarification (up to 95% and inferior when submitted to thermic scarification (reaching up to 43%; witness treatments showed germination between 2% and 13%. The results confirmed the presence of seed coat dormancy. It is recommendable, to break the dormancy of lots which are similar to the investigated ones (three to 27 months after seed collection, the immersion in sulfuric acid during 30 minutes. Seeds maintained its total germinative capacity after storage for 27 months in paper bag in cold chamber (5 °C and 98 % air humidity.Erythrina crista-galli L., Fabaceae, conhecida por corticeira-do-banhado, é uma árvore de porte médio, fixadora de nitrogênio, ocorrendo em vários biomas brasileiros, em terrenos alagadiços. Seu cultivo tem interesse para fins ornamentais e restauração ambiental. Informações sobre dormência tegumentar de suas sementes são conflitantes e imprecisas; por isso, o presente trabalho teve por objetivo verificá-la e, em caso positivo, definir métodos para a superação. O estudo foi composto por dois experimentos, usando lotes de sementes coletadas em datas diferentes. As sementes passaram por tratamentos de escarificação química (ácido sulfúrico comercial padrão ACS, d=1,84 g/cm³ e térmica (Directory of Open Access Journals (Sweden)
Muhamet eTopuz
2015-07-01
Full Text Available Biotypes of the broad-leaved wild mustard (Sinapis arvensis L. found in wheat fields of Aegean and Marmara region of Turkey were characterized and shown to have developed resistance to sulfonylurea (chlorsulfuron, an inhibitor of acetolactate synthase (ALS. DNA sequence analysis of the ALS genes from two such resistant (‘R’ biotypes, KNF-R1 and KNF-R2, revealed point mutations, CCT (Pro 197 to TCT (Ser 197 in KNF-R1 and CCT (Pro 197 to ACT (Thr 197 in KNF-R2; these substitutions are consistent with the presence of chlorsulfuron-insensitive ALS enzyme activity in the ‘R’ S. arvensis biotypes. An additional phenotype of chlorsulfuron resistance in the Turkish S. arvensis ‘R’ biotypes was revealed in the form of an altered seed dormancy behavior over 4 to 48 months of dry storage (after-ripening compared to the susceptible (‘S’ biotypes. Seeds of the ‘S’ biotypes dry stored for 4 months had a higher initial germination, which sharply decreased with storage time, while the seeds of the ‘R’ biotypes had lower germination after 4-months storage, rising sharply and peaking thereafter by 24 months’ of dry storage. The ‘R’ biotype seeds continued to maintain a higher germination percentage even after 48 months of after-ripening. The seed weight of ‘R’ and ‘S’ biotypes after-ripened for 4 months was similar but those after-ripened for 48 months differed, ‘R’ seeds were significantly heavier than those of the ‘S’ seeds. Differential seed germinability between ‘S’ and ‘R’ biotypes was found not a case of differential viability, temperature regimen or non-response to pro-germination hormone GA3. These studies are of relevance to ecological fitness of herbicide-resistant biotypes in terms of seed viability and germination.
Topuz, Muhamet; Nemli, Yildiz; Fatima, Tahira; Mattoo, Autar
2015-07-01
Biotypes of the broad-leaved wild mustard (Sinapis arvensis L.) found in wheat fields of Aegean and Marmara region of Turkey were characterized and shown to have developed resistance to sulfonylurea (chlorsulfuron), an inhibitor of acetolactate synthase (ALS). DNA sequence analysis of the ALS genes from two such resistant (‘R’) biotypes, KNF-R1 and KNF-R2, revealed point mutations, CCT (Pro 197) to TCT (Ser 197) in KNF-R1 and CCT (Pro 197) to ACT (Thr 197) in KNF-R2; these substitutions are consistent with the presence of chlorsulfuron-insensitive ALS enzyme activity in the ‘R’ S. arvensis biotypes. An additional phenotype of chlorsulfuron resistance in the Turkish S. arvensis ‘R’ biotypes was revealed in the form of an altered seed dormancy behavior over 4 to 48 months of dry storage (after-ripening) compared to the susceptible (‘S’) biotypes. Seeds of the ‘S’ biotypes dry stored for 4 months had a higher initial germination, which sharply decreased with storage time, while the seeds of the ‘R’ biotypes had lower germination after 4-months storage, rising sharply and peaking thereafter by 24 months’ of dry storage. The ‘R’ biotype seeds continued to maintain a higher germination percentage even after 48 months of after-ripening. The seed weight of ‘R’ and ‘S’ biotypes after-ripened for 4 months was similar but those after-ripened for 48 months differed, ‘R’ seeds were significantly heavier than those of the ‘S’ seeds. Differential seed germinability between ‘S’ and ‘R’ biotypes was found not a case of differential viability, temperature regimen or non-response to pro-germination hormone GA3. These studies are of relevance to ecological fitness of herbicide-resistant biotypes in terms of seed viability and germination.
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Vasileios A. Tzanakakis
2011-11-01
Full Text Available The effects of plant species (castor bean (Ricinus communis L. versus sunflower (Helianthus annus L. and irrigation regime (freshwater versus secondary treated municipal wastewater on soil properties and on seed and biodiesel yield were studied in a three year pot trial. Plant species were irrigated at rates according to their water requirements with either freshwater or wastewater effluent. Pots irrigated with freshwater received commercial fertilizer, containing N, P, and K, applied at the beginning of each irrigation period. The results obtained in this study showed that irrigation with effluent did not result in significant changes in soil pH, soil organic matter (SOM, total kjeldahl nitrogen (TKN, and dehydrogenase activity, whereas soil available P was found to increase in the upper soil layer. Soil salinity varied slightly throughout the experiment in effluent irrigated pots but no change was detected at the end of the experiment compared to the initial value, suggesting sufficient salt leaching. Pots irrigated with effluent had higher soil salinity, P, and dehydrogenase activity but lower SOM and TKN than freshwater irrigated pots. Sunflower showed greater SOM and TKN values than castor bean suggesting differences between plant species in the microorganisms carrying out C and N mineralization in the soil. Plant species irrigated with freshwater achieved higher seed yield compared to those irrigated with effluent probably reflecting the lower level of soil salinity in freshwater irrigated pots. Castor bean achieved greater seed yield than sunflower. Biodiesel production followed the pattern of seed yield. The findings of this study suggest that wastewater effluent can constitute an important source of irrigation water and nutrients for bioenergy crop cultivations with minor adverse impacts on soil properties and seed yield. Plant species play an important role with regard to the changes in soil properties and to the related factors of
Effect of two different plant growth regulators on production traits of sunflower
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Dávid ERNST
2016-12-01
Full Text Available The plant growth regulators (PGR are an organic compounds that modify plant physiological processes. PGR applied to the field crops promotes photosynthesis, stimulates plant growth, improves flowering and protects plants against unfavourable year weather conditions. Listed is an assumption to the yield of high quality. The effects of year weather conditions, biological material (hybrids and foliar application of two different PGR (Terra-Sorb® Foliar – containing free amino acids and Unicum® – containing Abiestins® on the yield-forming parameters, seed yield and the oil content in seeds of three selected hybrids of sunflower (NK Brio, NK Neoma, NK Ferti were studied in this paper. The field poly-factorial experiments were realized during two growing seasons of 2012 and 2013. The experimental area is situated in the maize-growing region (climatic region: warm; climatic sub-region: mild dry or dry; climatic zone: warm and dry, with mild winter and long sunshine and soil is silt loam Haplic Luvisol. The climatic conditions in chosen experimental years were different in quantities and distribution of precipitation at main growth period of sunflower plants (June to August and allows evaluating the yield stability between used hybrids and foliar treatments. The results showed that the application of selected PGR has contributed to an increase of sunflower seed yield, mainly through increase the weight of thousand seeds (rp = 0.761; P < 0.001. Similarly, oil content in seeds was significantly higher in treatments with PGR, especially with preparation Terra-Sorb® Foliar containing free amino acids. The study describes the relationship between quality (oil content in seeds and quantity (seed yield of sunflower production (rp = ‒0.41; P < 0.01. Results showed that PGR can be an important rationalization tool of the sunflower cultivation technology.
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Ungaro, Maria Regina Goncalves [Instituto Agronomico de Campinas, SP (Brazil). Secao de Oleaginosas; Toledo, Nilva Maria Prestes de [Instituto Agronomico de Campinas, SP (Brazil). Secao Tecnica Experimental e Calculo; Teixeira, Joao Paulo Feijao [Instituto Agronomico de Campinas, SP (Brazil). Secao de Fitoquimica; Suassuna Filho, Jose [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Dept.de Fisica
1993-12-31
Individual and group of seeds of some sunflower populations were utilized in order to evaluate the feasibility of oil content evaluations by the Nuclear Magnetic Resonance method (NMR). Correlation analysis with the extractive method (Soxhlet) was performed. The results showed that: the oil in the seeds behaved like a liquid in the NMR analysis; there was a high and positive correlation (r = 0,93) between NMR and Soxhlet; there was no correlation between seed weight and oil content; the observed variability in oil content among seeds of a plant were higher than between plants of a population; these values indicate the importance of making individual analysis of oil content by the NMR method for the sunflower breeding for oil content. (author) 7 refs., 2 figs., 4 tabs.
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Nelma de Mello Silva Oliveira
Full Text Available The objective of this research was to investigate the genotoxic potential of the oil of H. annuus L. (sunflower seeds via the Ames test as well as its oxidative properties and lipid composition. The pre-incubation method, system metabolic activation (S9 fraction and five S. typhimurium strains (TA97, TA98, TA100, TA1535 and TA102 were employed for the Ames test. The oxidative stability and fatty acid composition were analyzed by standard methods and gas chromatography. A revertant analysis showed no significant differences between the treatment doses (10–200 μl/plate and the negative controls, regardless of S9+ and S9−, and included all of the S. typhimurium strains. Chromatographic analysis showed high levels of polyunsaturated fatty acids, followed by monounsaturated, saturated and total trans-isomers. Among the polyunsaturated, monounsaturated and saturated fatty acids, linoleic, oleic and palmitic acids predominated. The results suggest that the sunflower oil is not genotoxic as indicated by frameshift mutations and base pair substitutions regardless of the treatment dose, but shows dose-dependent toxicity. The oxidative properties of the sunflower oil were consistent with the requirements of national and international standards. However, its composition could also indicate phytotherapeutic properties. Keywords: Helianthus annuus L., Sunflower oil, Genetic toxicity, Gas chromatography
Zhang, Rui; Baskin, J M; Baskin, C C; Mo, Qing; Chen, Lijun; Hu, Xiaowen; Wang, Yanrong
2017-10-24
Knowledge of the germination behavior of different populations of a species can be useful in the selection of appropriate seed sources for restoration. The aim of this study was to test the effect of seed population, collection year, after-ripening and incubation conditions on seed dormancy and germination of Stipa bungeana, a perennial grass used for revegetation of degraded grasslands on the Loess Plateau, China. Fresh S. bungeana seeds were collected from eight locally-adapted populations in 2015 and 2016. Dormancy and germination characteristics of fresh and 6-month-old dry-stored seeds were determined by incubating them over a range of alternating temperature regimes in light. Effect of water stress on germination was tested for fresh and 6-month-old dry-stored seeds. Seed dormancy and germination of S. bungeana differed with population and collection year. Six months of dry storage broke seed dormancy, broadened the temperature range for germination and increased among-population differences in germination percentage. The rank order of germination was not consistent in all germination tests, and it varied among populations. Thus, studies on comparing seed dormancy and germination among populations must consider year of collection, seed dormancy states and germination test conditions when selecting seeds for grassland restoration and management.
Cultivation of sunflower and its utilization in livestock
International Nuclear Information System (INIS)
Imran, M.; Hussain, A.; Khan, S.
2008-01-01
The sunflower is valuable from economic, as well as ornamental point of view. Every part of the plant may be utilized for some economic purpose. The leaves form a cattle-food and the stems contain a fibre, which may be used successfully in making paper. (Khan and Rana, 1966). The leaves form a cattle-food and the stems contain a fibre, which may be used successfully in making paper. (Khan and Rana, 1966). The seed is rich in oil, which is said to be more near to olive oil, than any other vegetable oil known, and to be largely used as a substitute. In prewar days, sunflower seed was sometimes grown in this country, especially on sewage farms, as an economical crop for pheasants, as well as poultry. The flowers contain a yellow dye. The oil extracted from the seeds is of citron yellow colour and sweet in taste. Sunflower seeds have a high feedings value the analysis in round figures in 16 per cent albumen and 21 per cent fat. Being so rich in oil, they are too stimulating to use alone and should only be used in combination with other feeding stuffs. Mixed with oats in equal quantities, they make a perfectly balanced ration. (author)
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International Nuclear Information System (INIS)
Shah, Mazloom; Tariq, Muhammad; Ali, Saqib; Guo, Qing-Xiang; Fu, Yao
2014-01-01
The methanolysis of jojoba oil has been studied in the presence of tin powder, dibutyltin diacetate (C 4 H 9 ) 2 Sn(OOCCH 3 ) 2 , dioctyltin diacetate (C 8 H 17 ) 2 Sn(OOCCH 3 ) 2 , dibutyltin oxide (C 4 H 9 ) 2 SnO, dioctyltin oxide (C 8 H 17 ) 2 SnO, diphenyltin oxide (C 6 H 5 ) 2 SnO, dibutyltin chloride dihydroxide (C 4 H 9 ) 2 Sn(OH) 2 Cl, butyltinhydroxide hydrate (C 4 H 9 )Sn(=O)OH.xH 2 O, Ni nanoparticles and Pd nanoparticles act as catalysts. Among these, 1 weight % of dibutyltin diacetate shows the maximum conversion. Then, methanolysis of sunflower oil, neem oil, rocket seed oil and linseed oil into methyl esters studied in the presence of 1% dibutyltin diacetate as a catalyst and was compared their percentage conversions. The experimental yield for the conversion of jojoba oil, sunflower oil, neem oil, rocket seed oil and linseed oil into biodiesel was found to be 71%, 51%, 50.78%, 40.90% and 39.66%, respectively. The experimental yield of the conversion of jojoba oil into methyl esters was found to be increased up to 96% by increasing reaction time, without emulsion formation. The synthesis of jojoba seed oil biodiesel (JSOB), soybean oil biodiesel (SOB), neem oil biodiesel (NOB), rocket seed oil biodiesel (RSOB) and linseed oil biodiesel (LSOB) was confirmed by NMR ( 1 H and 13 C) and FT-IR analyses of biodiesel. - Highlights: • Transesterification of jojoba oil into biodiesel by tin and nano catalysts. • 1 weight % dibutyltin diacetate showed highest yield at 60 °C. • Catalytic conversion comparison of five oils using dibutyltin diacetate • The experimental yield of the conversion of jojoba oil increased with time. • FT-IR and NMR ( 1 H and 13 C) characterization
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Directory of Open Access Journals (Sweden)
T. A. Morsy
2015-08-01
Full Text Available This study aimed to investigate the effect of sunflower seeds, either as whole or as oil, on rumen fermentation, milk production, milk composition and fatty acids profile in dairy goats. Fifteen lactating Damascus goats were divided randomly into three groups (n = 5 fed a basal diet of concentrate feed mixture and fresh Trifolium alexandrinum at 50:50 on dry matter basis (Control in addition to 50 g/head/d sunflower seeds whole (SS or 20 mL/head/d sunflower seeds oil (SO in a complete randomized design. Milk was sampled every two weeks during 90 days of experimental period for chemical analysis and rumen was sampled at 30, 60, and 90 days of the experiment for ruminal pH, volatile fatty acids (tVFA, and ammonia-N determination. Addition of SO decreased (p = 0.017 ruminal pH, whereas SO and SS increased tVFA (p<0.001 and acetate (p = 0.034 concentrations. Serum glucose increased (p = 0.013 in SO and SS goats vs Control. The SO and SS treated goats had improved milk yield (p = 0.007 and milk fat content (p = 0.002. Moreover, SO increased milk lactose content (p = 0.048 and feed efficiency (p = 0.046 compared to Control. Both of SS and SO increased (p<0.05 milk unsaturated fatty acids content specially conjugated linolenic acid (CLA vs Control. Addition of SS and SO increased (p = 0. 021 C18:3N3 fatty acid compared to Control diet. Data suggested that addition of either SS or SO to lactating goats ration had beneficial effects on milk yield and milk composition with enhancing milk content of healthy fatty acids (CLA and omega 3, without detrimental effects on animal performance.
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Finch-Savage, W.E.; Cadman, C.S.C.; Toorop, P.E.; Lynn, J.R.; Hilhorst, H.W.M.
2007-01-01
The depth of seed dormancy can be influenced by a number of different environmental signals, but whether a common mechanism underlies this apparently similar response has yet to be investigated. Full-genome microarrays were used for a global transcript analysis of Arabidopsis thaliana Cape Verde
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Directory of Open Access Journals (Sweden)
Yulianti Bramasto
2016-12-01
Full Text Available The procurement of good quality seeds for the development of mindi (Melia azedarach L. in the community forest is absolutely necessary. The purpose of this research is to investigate the diversity of the viability and seedling vigor of mindi from different populations with various treatments of dormancy breaking. The sample materials were mindi seeds that were collected from 6 locations (6 seed lots or seed sources which were located in the community forest of West Java. There are 10 treatments of dormancy breaking that were applied in this study. The experiment design was Randomized Complete Design (RAL. The breaking dormancy was focused to the delignification of hard seed coat. Results showed that the most effective dormancy breaking for mindi seed was soaking in consentrated Sulfuric Acid (H2SO4 as long as 30 to 45 minutes. The first count for germination of mindi was on the 16 day and the final count was on the 31 day.The average value of germination percentage (DB for all seed sources was 40 %, while the highest which is 60% was mindi from Sumedang seed source. The highest value of germination rate that is 6,543%/etmal was seed from Sumedangand seed from Gambung was the lowest (1,400 %/etmal. Keywords : community forest, Melia azedarach L., variation, viability, vigor.
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Banded sunflower moth, Cochylis hospes Walsingham, is one of the most destructive seed-feeding insect pests of sunflowers, causing significant economic yield losses in the northern Great Plains. In an attempt to understand host-plant resistance mechanisms for this pest, we field tested over several ...
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Response and utilization of phosphorus by sunflower
International Nuclear Information System (INIS)
Venkata Reddy, P.; Sreenivasa Raju, A.; Prasad Rao, A.; Sultana, Fatima
1997-01-01
A field experiment was carried out to find the response and utilization of applied P by sunflower at different levels of N, in the light soils of Andhra Pradesh using 32 P labelled fertilizer. The results of the experiment clearly brought out the significant effects of N and P application on the dry matter yield, per cent Pdff and P utilization of sunflower at flowering and seed yield at harvest
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Energy Technology Data Exchange (ETDEWEB)
Harder, Marcia N.C.; Nogueira, Neusa L.; Arthur, Valter; Rossi, Monica L.; Rodriguez, Adriana P.M. [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)]. E-mails: mnharder@cena.usp.br; nogueira@cena.usp.br; arthur@cena.usp.br; mnicalr@cena.usp.br; riana@cena.usp.br
2007-07-01
The annatto (Bixa orellana) is the only species of the Bixaceae family. From the seeds an important food colorant is obtained, bixin, for the industry and domestic use. More recently studies have focused more extensively in medicinal purpose of the species. Due to structural and physiologic characteristics, the seeds have low germination rate, around 30 %. The irradiation of seeds with gamma radiation can promote the increase and/or acceleration of germination, better plant development and productivity, among other aspects. The radiation doses used for this purpose should not cause genetic modifications in the organism, hence experimentation is needed to define the appropriate doses. Absence of research done annatto related to the use of the irradiation aiming at the increase of germination rates lead to the structural characterization of the annatto seeds submitted to gamma radiation through transmission (TEM) and scanning electron microscopy (SEM). The objective of this study was to verify the effect of radiation on the seeds structures during the process of dormancy break. Dry seeds and seeds immersed in distilled water for 24 hours were submitted to gamma radiation from source of Co{sup 60} type Gammacell-220 at CENA/USP, at doses 100 Gy. After irradiation the seeds were processed for TEM and SEM. Preliminary results, showed structural modifications in the seeds. (author)
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Understanding Lolium rigidum Seeds: The Key to Managing a Problem Weed?
Directory of Open Access Journals (Sweden)
Kathryn J. Steadman
2012-09-01
Full Text Available The 40 million hectare southern Australian winter cropping region suffers from widespread infestation by Lolium rigidum (commonly known as annual or rigid ryegrass, a Mediterranean species initially introduced as a pasture plant. Along with its high competitiveness within crops, rapid adaptability and widespread resistance to herbicides, the dormancy of its seeds means that L. rigidum is the primary weed in southern Australian agriculture. With the individuals within a L. rigidum population exhibiting varying levels of seed dormancy, germination can be staggered across the crop-growing season, making complete weed removal virtually impossible, and ensuring that the weed seed bank is constantly replenished. By understanding the processes involved in induction and release of dormancy in L. rigidum seeds, it may be possible to develop strategies to more effectively manage this pest without further stretching herbicide resources. This review examines L. rigidum seed dormancy and germination from a weed-management perspective and explains how the seed bank can be depleted by control strategies encompassing all stages in the lifecycle of a seed, from development to germination.
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Directory of Open Access Journals (Sweden)
JAVIER A. FIGUEROA
2004-03-01
un modelo estructural y funcional del banco de semillas para el matorral de Chile central, que debería ser enriquecido con futuras investigacionesSeed banks on Mediterranean regions display characteristics that distinguish them from the seed banks of other regions. A seed bank is the concentration of viable propagules buried in the soil for variable periods of time. Seed banks in the Chilean matorral are chiefly transient and functionally similar to seed banks in other Mediterranean ecosystems not disturbed by fire, except for those of Australia. A transient seed bank is that composed of seeds that cannot survive in the upper levels of the soil for more than 1 year. The density of herb seeds in the Chilean matorral soil is one of the highest among Mediterranean ecosystems anywhere in the world, and a large proportion of these seeds is made up of seeds without dormancy that germinate easily, particularly annual grasses. With respect to the dormancy mechanisms that may be responsible for the behavior of these seeds stored in the transient bank, our analysis revealed the following germination syndromes: (1 species whose seeds must be stratified in cold due to the presence of physiological dormancy (particularly introduced herbs, (2 species whose seeds must be scarified with acids or mechanical means due to the presence of physical dormancy (mainly native woody species and, (3 species that present physiological dormancy and need heat stratification to activate germination (both native and introduced species. These syndromes determine that the timing of germination in central Chile has an autumn and an early spring phase. Besides, there is absence of sporadic germination syndromes for the components of a persistent seed bank. We propose a structural and functional model of the seed bank for the matorral of central Chile that should be enriched with future research
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Banaś, Walentyna; Sanchez Garcia, Alicia; Banaś, Antoni; Stymne, Sten
2013-06-01
The last step in triacylglycerols (TAG) biosynthesis in oil seeds, the acylation of diacylglycerols (DAG), is catalysed by two types of enzymes: the acyl-CoA:diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). The relative contribution of these enzymes in the synthesis of TAG has not yet been defined in any plant tissue. In the presented work, microsomal preparations were obtained from sunflower and safflower seeds at different stages of development and used in DGAT and PDAT enzyme assays. The ratio between PDAT and DGAT activity differed dramatically between the two different species. DGAT activities were measured with two different acyl acceptors and assay methods using two different acyl-CoAs, and in all cases the ratio of PDAT to DGAT activity was significantly higher in safflower than sunflower. The sunflower DGAT, measured by both methods, showed significant higher activity with 18:2-CoA than with 18:1-CoA, whereas the opposite specificity was seen with the safflower enzyme. The specificities of PDAT on the other hand, were similar in both species with 18:2-phosphatidylcholine being a better acyl donor than 18:1-PC and with acyl groups at the sn-2 position utilised about fourfold the rate of the sn-1 position. No DAG:DAG transacylase activity could be detected in the microsomal preparations.
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International Nuclear Information System (INIS)
Akram, M.; Aftab, F.
2016-01-01
In the present study, fruits (drupes) were collected from Changa Manga Forest Plus Trees (CMF-PT), Changa Manga Forest Teak Stand (CMF-TS) and Punjab University Botanical Gardens (PUBG) and categorized into very large (= 17 mm dia.), large (12-16 mm dia.), medium (9-11 mm dia.) or small (6-8 mm dia.) fruit size grades. Fresh water as well as mechanical scarification and stratification were tested for breaking seed dormancy. Viability status of seeds was estimated by cutting test, X-rays and In vitro seed germination. Out of 2595 fruits from CMF-PT, 500 fruits were of very large grade. This fruit category also had highest individual fruit weight (0.58 g) with more number of 4-seeded fruits (5.29 percent) and fair germination potential (35.32 percent). Generally, most of the fruits were 1-seeded irrespective of size grades and sampling sites. Fresh water scarification had strong effect on germination (44.30 percent) as compared to mechanical scarification and cold stratification after 40 days of sowing. Similarly, sampling sites and fruit size grades also had significant influence on germination. Highest germination (82.33 percent) was obtained on MS (Murashige and Skoog) agar-solidified medium as compared to Woody Plant Medium (WPM) (69.22 percent). Seedlings from all the media were transferred to ex vitro conditions in the greenhouse and achieved highest survival (28.6 percent) from seedlings previously raised on MS agar-solidified medium after 40 days. There was an association between the studied parameters of teak seeds and the sampling sites and fruit size. (author)
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Arana, María V; Gonzalez-Polo, Marina; Martinez-Meier, Alejandro; Gallo, Leonardo A; Benech-Arnold, Roberto L; Sánchez, Rodolfo A; Batlla, Diego
2016-01-01
Seeds integrate environmental cues that modulate their dormancy and germination. Although many mechanisms have been identified in laboratory experiments, their contribution to germination dynamics in existing communities and their involvement in defining species habitats remain elusive. By coupling mathematical models with ecological data we investigated the contribution of seed temperature responses to the dynamics of germination of three Nothofagus species that are sharply distributed across different altitudes in the Patagonian Andes. Seed responsiveness to temperature of the three Nothofagus species was linked to the thermal characteristics of their preferred ecological niche. In their natural distribution range, there was overlap in the timing of germination of the species, which was restricted to mid-spring. By contrast, outside their species distribution range, germination was temporally uncoupled with altitude. This phenomenon was described mathematically by the interplay between interspecific differences in seed population thermal parameters and the range in soil thermic environments across different altitudes. The observed interspecific variations in seed responsiveness to temperature and its environmental regulation, constitute a major determinant of the dynamics of Nothofagus germination across elevations. This phenomenon likely contributes to the maintenance of patterns of species abundance across altitude by placing germinated seeds in a favorable environment for plant growth. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
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How seed orchard culture affects seed quality: experience with the southern pines
James P. Barnett
1996-01-01
Tree improvement programs have influenced significantly the quality of southern pine seeds produced when compared to collections from native stands. Seed orchard management practices such as fertilization can increase seed size and reduce seed dormancy. These result in the need for less complex pregermination treatments. Repeated cone collections from the same clones...
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Directory of Open Access Journals (Sweden)
Elane Grazielle Borba de Sousa Ferreira
2012-05-01
Full Text Available O presente trabalho teve como objetivo avaliar o efeito de diferentes tratamentos pré-germinativos na superação da dormência de sementes de Celosia cristata L., que foram submetidas aos seguintes tratamentos: choque térmico - exposição em estufa a 80°C por 5 minutos, escarificação química com ácido sulfúrico por um minuto, 30 segundos e 5 minutos, imersão das sementes intactas em água a 80°C até resfriamento, imersão das sementes intactas em água à temperatura ambiente por 24 horas e a testemunha - sem tratamento. Na avaliação do efeito dos tratamentos, foram determinados a porcentagem final, primeira contagem e índice de velocidade de germinação, como também o comprimento da raiz e do hipocótilo. As sementes de C. cristata L. quando oriundas de frutos maduros não necessitam da utilização de tratamentos para superação da dormência.This study had the objective of evaluating the effect of different pre-germination treatments for overcome of dormancy of Celosia cristata seeds, subjected to the following treatments: heat shock - exhibition in an oven at 80°C for 5 minutes, chemical scarification with sulfuric acid for 1 minute, 30 seconds and 5 minutes, immersion of intact seeds in water the 80°C at cooling and immersion of intact seeds in water for 24 hours, and the control - no treatment. We evaluated the following final percentage, first count and germination speed index, but also the length of the primary root and hypocotyl. The seeds of C. cristata when coming from ripe fruits do not require the use of treatments to overcoming dormancy.
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Gamma radiation induced mutant for improved yield components in sunflower
International Nuclear Information System (INIS)
Elangovan, M.
2001-01-01
Sunflower has become an important oilseed in the Indian vegetable oil pool following its introduction from Russia in 1969. It can be used for all quality products useful to humans. The need for genetic variability and new useful gene sources has necessitated that sunflower breeders and geneticists utilize a wide range of germplasm in their breeding programmes. The induction of mutations in sunflower by physical and chemical mutagens has been practiced quite intensively in the last two decades. The results recorded to date suggest that utilization of mutagenesis could be a great advantage in improving the sunflower crop. An induced mutation programme was undertaken to generate variability in the variety 'Morden' using gamma rays. The certified and genetically pure seeds were irradiated with 50, 100, and 150 Gy gamma rays and used for further studies. Selection in M 2 generations, raised from different treatments, revealed the presence of an erectophylly leaf mutant from 50 Gy treatment. The isolated mutant showed improved yield components like head diameter, 100- seed weight and yield per plant. The mutant was a plant with short petiole length and erect leaves. This type of leaf get sunlight throughout the day. From morning to afternoon, the first half of the leaf gets sunlight, and from afternoon to evening the second half of the leaf gets sunlight. As a result of getting sunlight the whole day, the plant had more photosynthetic products and grew vigorously. Plant height, head diameter and 100-seed weight had direct effect on seed yield, and the number of leaves and stem diameter influenced the seed yield indirectly. In the M 3 generation, the mutant showed an almost two-fold increase over the parent variety for all investigated characters, except that of the yield per plant where there was a three-fold increase. The present investigation has shown that there are remarkable possibilities of increasing the yield components in sunflower by induced mutations
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Sunflower disease and insect pests in Pakistan: A review | Mukhtar ...
African Journals Online (AJOL)
Sun flower (Helianthus annuus L.) is one of the important oil seed crops and potentially fit in agricultural system and oil production sector of Pakistan. Various diseases, insects and nematodes attack damage the sunflower crop, results a wide range of loss in production and yield. Sunflower is susceptible to diseases of ...
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Mutagenic effectiveness and efficiency in varieties of sunflower ...
African Journals Online (AJOL)
GREGORY
2010-09-27
Sep 27, 2010 ... The effect of single treatment with gamma-rays, sodium azide and combination treatments of gamma- rays and sodium azide on seed germination, seedling survival, pollen fertility and seed set in sunflower. (Helianthus annuus L.) M2 generation was studied in the varieties of USH-430 and SHSF-333.
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Directory of Open Access Journals (Sweden)
Yolanda González
2009-12-01
Full Text Available Se desarrolló un experimento con semillas de accesiones de Leucaena spp. cosechadas en suelo ácido y almacenadas bajo condiciones ambientales, para determinar el período e intensidad de la dormancia y su ruptura. Para ello se empleó un diseño de clasificación simple y cuatro réplicas, con los siguientes tratamientos: 1 semilla sin tratar (control; 2 corte de cubierta; y 3 agua a 80°C durante 2 minutos. En cada una de las accesiones hubo diferencias significativas entre los tratamientos aplicados y los mayores valores de germinación se encontraron con el corte de cubierta. Todas las accesiones mostraron estado dormático (entre 10 y 98%, el cual se apreció en la germinación del control y en la viabilidad con el corte de cubierta. Los mayores valores de dormancia en las semillas cosechadas en el 2006 se detectaron en L. macrophylla CIAT 17233, L. macrophylla CIAT 17231, L. diversifolia CIAT 17270 y L. leucocephala IH-1140, cuya dureza fue de 98,0; 97,0; 80,0 y 74,7%, respectivamente; en las cosechadas en el 2003 y 2004, los porcentajes de dureza fueron de 89,0; 69,0 y 60,0% para L. lanceolata CIAT 17252, L. macrophylla CIAT 17238 y L. leucocephala cv. K-67, respectivamente. Se concluye que las semillas de las accesiones presentaron dormancia poscosecha, que varió entre 10 y 98%. Además la escarificación térmica provocó su ruptura, por lo que se recomienda aplicar este procedimiento antes de la siembra a las semillas de Leucaena spp. que se cosechen en suelo ácido de Cascajal.A trial was conducted with seeds of Leucaena spp accessions harvested on acid soil and stored under ambient conditions, in order to determine the period and intensity of dormancy and its breaking. For that purpose a simple classification design and four replications were used, with the following treatments: 1 untreated seed (control; 2 coat cut; and 3 water at 80ºC for 2 minutes. In each one of the accessions there were significant differences among the
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Zhang, Keliang; Baskin, Jerry M; Baskin, Carol C; Yang, Xuejun; Huang, Zhenying
2015-06-01
Many congeneric species are disjunct between eastern Asia and eastern North America. No previous study has compared the seed biology of closely related disjunct taxa of legumes or of a diaspore-heteromorphic species. Our objective was to compare seed dormancy in two such sister species in the genus Amphicarpaea (Fabaceae). We investigated the ecology and ecophysiology of aerial and subterranean seeds of the amphicarpic species Amphicarpaea edgeworthii from China and compared the results to those published for its sister species A. bracteata from eastern North America. The seed coat of aerial seeds of A. edgeworthii is well developed, whereas the seed coat of subterranean seeds is not. Aerial seeds have combinational dormancy (physical dormancy [PY] + physiological dormancy [PD]) broken by scarification followed by cold stratification or by after-ripening and scarification; whereas subterranean seeds have PD broken by cold stratification. Aerial seeds formed a persistent soil seed bank, and subterranean seeds a transient soil seed bank. Aerial seeds of A. bracteata also have PY+PD and subterranean seeds PD. Subterranean seeds of both species are desiccation intolerant. Dormancy in neither aerial nor subterranean seeds of both species has diverged over geological time. Compared to subterranean seeds, aerial seeds of both species dispersed over longer distances. Seed dispersal ability and degree of dormancy of neither species fits the high-risk/low-risk (H-H/L-L) strategy found in many diaspore-dimorphic species. Rather, both species have an H-L/L-H strategy for these two life history traits. © 2015 Botanical Society of America, Inc.
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Liquid sorting and film coating : techniques for improving tree seed performance
Derkx, M.P.M.
2006-01-01
Tree seed performance has benefited considerably from the development of controlled methods to overcome dormancy. Traditionally tree seeds have often been stratified outdoors. Depending on the types of dormancy, stratification starts before or during summer and continues during winter, or it starts
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Gene transfer from wild Helianthus to sunflower: topicalities and limits
Directory of Open Access Journals (Sweden)
Breton Catherine
2010-03-01
Full Text Available Sunflower (2n=17 belongs to the Helianthus genus (Asteraceae. Wild Helianthus species display morphological variation for branching and stem number, for architecture and seed size, and for resistance to abiotic and biotic stresses due to which they thrive in different environments in North America. The genus is divided into botanical sections, two for annual as sunflower, and two for perennial species as Jerusalem artichoke that produces rhizomes (tubers. We explain the difficulties and successes obtained by crossing sunflower with these species to improve the agronomic traits of the sunflower crop. It is easier to cross the annual species than the perennials’ with sunflower. Several traits such as Cytoplasmic male sterility and restorer Rf-PET1 genes, Downy mildew resistance, Phomopsis resistance, Sclerotinia resistance, Rust resistance, and Orobanche resistance have already been introduced from annual species into sunflower crop, but the complex genomic organization of these species compared to sunflower limits their important potential. Perennial species are much more diverse, and their genomes display 2n, 4n, or 6n chromosomes for n 17. The realities of inter-specific hybridization are relatively disappointing due to the introgression lines that have low oil and low seed yield. We report here several attempts to introgress agronomic traits from these species to sunflower, and we present as a case study, an introgressed progenies from H. mollis, a diploid species with sessile small leaves. We constructed a preliminary genetic map with AFLP markers in 21 BC1 plants, and we then showed that some progenies display 6 to 44% of introgression from H. mollis. Although this study is promising due to the novel compact architecture of the progenies, we cannot estimate the transferability from H. mollis to other perennial Helianthus to improve sunflower.
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[Study on physiological and germination characteristics of Tulipa edulis seed].
Wu, Zhengjun; Zhu, Zaibiao; Guo, Qiaosheng; Ma, Hongliang; Xu, Hongjian; Miao, Yuanyuan
2012-03-01
Current study was conducted to investigate the seed physiological characteristics of Tulipa edulis and improve germination rate. Anatomical characteristics was observed. Seed water absorption curve was tested by soaking method. Dynamic of embryo development and germination rate as well as germination index under different conditions were recorded. And the biological test of cabbage seed was used for detecting the germination inhibitors. The embryo rate of newly matured seeds was about 10%, and there was no obstacle of water absorption on testa of T. edulis. The optimum method for embryo development was exposure to 300 mg x L(-1) gibberellin solution for 24 hours, and stratification at 25 degrees C for 70 days followed by stratification at 5 degrees C for 40 days. The germintion rate and germination index of dormancy-broken seeds under the dark environment at 10 degrees C and 15 degrees C were significantly higher than those under other conditions. Additionally, there were some germination inhibitory substances in dry seeds. The seed of T. edulis can be classified as having complex morphophysiological dormancy, and the morphological embryo dormancy played a leading role. Warm and cold stratification resulted in a fast dormancy breaking effect, and a high germination rate more than 90% could be obtained under the optimum conditions.
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EPR spin probe investigation of irradiated wheat, rice and sunflower seeds
Energy Technology Data Exchange (ETDEWEB)
Paktas, Dilek Dadayl [Department of Physics, Faculty of Art and Science, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey)]. E-mail: dadayli@karaelmas.edu.tr; Suennetcioglu, M. Maral [Department of Physics Engineering, Hacettepe University, 06532 Beytepe, Ankara (Turkey)
2007-01-15
TEMPO and 4-nitro-TEMPO spin probes were used to monitor dose-dependent changes in the EPR spectra of irradiated wheat and rice embryos and sunflower embryo parts. Rice embryos were studied in the 233-293 K temperature range using 4-nitro-TEMPO. TEMPAMINE, TEMPYO and DTBN spin probes were also studied for their applicability in the determination of irradiated seeds. All the recorded spectra were simulated, and spectral parameters and partition of the probes among various domains were determined. Despite the contribution of the signal from extracellular regions, it was possible to detect the changes in the water/lipid ratios with dose. The hydrophilic character of the probe alone was not sufficient to distinguish the different doses of irradiation. Line widths and rotational correlation times of various domains within embryo also play an important role. Partition after dehydration was another measure in the selection of the suitable probes for irradiation studies. Better results were obtained in dehydrated embryos for the probes preferring lipid bodies.
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Directory of Open Access Journals (Sweden)
Aguirre Marta R.
2014-11-01
Full Text Available In this study we evaluate the chemical composition of sunflower oils obtained separately by pressing and subsequent solvent extraction from a new seeds rich in phytosterols (IASP-18 and conventional seeds (HA-89. Results have shown that the total content of oil was much lower in the IASP-18 (18.1% than in the conventional (37.5% seeds. The extraction yield obtained by pressing was as low as 3% in the IASP-18 seeds and 37.5% in HA-89, while in the solvent extraction it was of the same order (~18 wt% on seeds extracted by pressing for the two types of seeds. No significant changes in the fatty acid composition were found between the oils extracted by the two procedures, but the pressed oils presented significantly lower acidity and larger content of the unsaponifiable fraction. Expressed as free sterols, the total sterols were 37–38% more concentrated in the oils extracted with solvent, reaching amounts of 13 700 and 6500 mg/kg in the IASP-18 and HA-89 oils, respectively. No substantial differences were found in the composition of total sterols analysed as free sterols between the oils extracted with the two procedures, but the contents of free sterols and sterol glycosides were much higher in the oils extracted with solvent.
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Ismuhajaroh, Bakti Nur
2014-01-01
The purpose of the study was to find out the dormancy breaking and the seed germination of Asam kuranji (Dialium indum L.) mechanically by sandpapering the seeds and chemically by immersing them in sulfuric acid (H2SO4). The experiment was conducted at the Plant Physiology Laboratory of Agricultural Faculty of Lambung Mangkurat University from June - August 2013 using Completely Randomized Design (CRD) with 2 x 4 factorial. The first factor was the mechanical treatment (s0 = without sandpape...
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Seed cryopreservation of Fraxinus angustifolia Vahl
African Journals Online (AJOL)
Università
2013-04-17
control) and liquid nitrogen-treated seeds were .... 76.0 ± 4.0 (NT in GA3), with an intermediary value of 70.0. ± 5.0% (Cryo seeds in water .... in November, suggesting a loss of dormancy during seed maturation. Furthermore, seed ...
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Wang, Lei; Huang, Zhenying; Baskin, Carol C; Baskin, Jerry M; Dong, Ming
2008-11-01
Suaeda aralocaspica is a C4 summer annual halophyte without Kranz anatomy that is restricted to the deserts of central Asia. It produces two distinct types of seeds that differ in colour, shape and size. The primary aims of the present study were to compare the dormancy and germination characteristics of dimorphic seeds of S. aralocaspica and to develop a conceptual model of their dynamics. Temperatures simulating those in the natural habitat of S. aralocaspica were used to test for primary dormancy and germination behaviour of fresh brown and black seeds. The effects of cold stratification, gibberellic acid, seed coat scarification, seed coat removal and dry storage on dormancy breaking were tested in black seeds. Germination percentage and recovery responses of brown seeds, non-treated black seeds and 8-week cold-stratified black seeds to salt stress were tested. Brown seeds were non-dormant, whereas black seeds had non-deep Type 2 physiological dormancy (PD). Germination percentage and rate of germination of brown seeds and of variously pretreated black seeds were significantly higher than those of non-pretreated black seeds. Exposure of seeds to various salinities had significant effects on germination, germination recovery and induction into secondary dormancy. A conceptual model is presented that ties these results together and puts them into an ecological context. The two seed morphs of S. aralocaspica exhibit distinct differences in dormancy and germination characteristics. Suaeda aralocaspica is the first cold desert halophyte for which non-deep Type 2 PD has been documented.
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Lillesand, T.; Seeley, M.
1983-01-01
Stress in sunflowers was assessed in western and northwestern Minnesota. Weekly ground observations (acquired in 1980 and 1981) were analyzed in concert with large scale aerial photography and concurrent LANDSAT data. Using multidate supervised and unsupervised classification procedures, it was found that all crops grown in association with sunflowers in the study area are spectrally separable from one another. Under conditions of extreme drought, severely stressed plants were differentiable from those not severely stressed, but between-crop separation was not possible. Initial regression analyses to estimate sunflower seed yield showed a sensitivity to environmental stress during the flowering and seed development stages. One of the most important biological factors related to sunflower production in the Red River Valley area was found to be the extent and severity of insect infestations.
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Directory of Open Access Journals (Sweden)
Vijaya R Chitnis
Full Text Available Maintenance and release of seed dormancy is regulated by plant hormones; their levels and seed sensitivity being the critical factors. This study reports transcriptional regulation of brassinosteroids (BR, ethylene (ET, cytokinin (CK and salicylic acid (SA related wheat genes by after-ripening, a period of dry storage that decays dormancy. Changes in the expression of hormonal genes due to seed after-ripening did not occur in the anhydrobiotic state but rather in the hydrated state. After-ripening induced dormancy decay appears to be associated with imbibition mediated increase in the synthesis and signalling of BR, via transcriptional activation of de-etiolated2, dwarf4 and brassinosteroid signaling kinase, and repression of brassinosteroid insensitive 2. Our analysis is also suggestive of the significance of increased ET production, as reflected by enhanced transcription of 1-aminocyclopropane-1-carboxylic acid oxidase in after-ripened seeds, and tight regulation of seed response to ET in regulating dormancy decay. Differential transcriptions of lonely guy, zeatin O-glucosyltransferases and cytokinin oxidases, and pseudo-response regulator between dormant and after-ripened seeds implicate CK in the regulation of seed dormancy in wheat. Our analysis also reflects the association of dormancy decay in wheat with seed SA level and NPR independent SA signaling that appear to be regulated transcriptionally by phenylalanine ammonia lyase, and whirly and suppressor of npr1 inducible1 genes, respectively. Co-expression clustering of the hormonal genes implies the significance of synergistic and antagonistic interaction between the different plant hormones in regulating wheat seed dormancy. These results contribute to further our understanding of the molecular features controlling seed dormancy in wheat.
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Directory of Open Access Journals (Sweden)
Saminathan Subburaj
Full Text Available The rice gene seed dormancy 4 (OsSdr4 functions in seed dormancy and is a major factor associated with pre-harvest sprouting (PHS. Although previous studies of this protein family were reported for rice and other species, knowledge of the evolution of genes homologous to OsSdr4 in plants remains inadequate. Fifty four Sdr4-like (hereafter designated Sdr4L genes were identified in nine plant lineages including 36 species. Phylogenetic analysis placed these genes in eight subfamilies (I-VIII. Genes from the same lineage clustered together, supported by analysis of conserved motifs and exon-intron patterns. Segmental duplications were present in both dicot and monocot clusters, while tandemly duplicated genes occurred only in monocot clusters indicating that both tandem and segmental duplications contributed to expansion of the grass I and II subfamilies. Estimation of the approximate ages of the duplication events indicated that ancestral Sdr4 genes evolved from a common angiosperm ancestor, about 160 million years ago (MYA. Moreover, diversification of Sdr4L genes in mono and dicot plants was mainly associated with genome-wide duplication and speciation events. Functional divergence was observed in all subfamily pairs, except IV/VIIIa. Further analysis indicated that functional constraints between subfamily pairs I/II, I/VIIIb, II/VI, II/VIIIb, II/IV, and VI/VIIIb were statistically significant. Site and branch-site model analyses of positive selection suggested that these genes were under strong adaptive selection pressure. Critical amino acids detected for both functional divergence and positive selection were mostly located in the loops, pointing to functional importance of these regions in this protein family. In addition, differential expression studies by transcriptome atlas of 11 Sdr4L genes showed that the duplicated genes may have undergone divergence in expression between plant species. Our findings showed that Sdr4L genes are
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The sunflower downy mildew pathogen Plasmopara halstedii.
Gascuel, Quentin; Martinez, Yves; Boniface, Marie-Claude; Vear, Felicity; Pichon, Magalie; Godiard, Laurence
2015-02-01
Downy mildew of sunflower is caused by Plasmopara halstedii (Farlow) Berlese & de Toni. Plasmopara halstedii is an obligate biotrophic oomycete pathogen that attacks annual Helianthus species and cultivated sunflower, Helianthus annuus. Depending on the sunflower developmental stage at which infection occurs, the characteristic symptoms range from young seedling death, plant dwarfing, leaf bleaching and sporulation to the production of infertile flowers. Downy mildew attacks can have a great economic impact on sunflower crops, and several Pl resistance genes are present in cultivars to protect them against the disease. Nevertheless, some of these resistances have been overcome by the occurrence of novel isolates of the pathogen showing increased virulence. A better characterization of P. halstedii infection and dissemination mechanisms, and the identification of the molecular basis of the interaction with sunflower, is a prerequisite to efficiently fight this pathogen. This review summarizes what is currently known about P. halstedii, provides new insights into its infection cycle on resistant and susceptible sunflower lines using scanning electron and light microscopy imaging, and sheds light on the pathogenicity factors of P. halstedii obtained from recent molecular data. Kingdom Stramenopila; Phylum Oomycota; Class Oomycetes; Order Peronosporales; Family Peronosporaceae; Genus Plasmopara; Species Plasmopara halstedii. Sunflower seedling damping off, dwarfing of the plant, bleaching of leaves, starting from veins, and visible white sporulation, initially on the lower side of cotyledons and leaves. Plasmopara halstedii infection may severely impact sunflower seed yield. In spring, germination of overwintered sexual oospores leads to sunflower root infection. Intercellular hyphae are responsible for systemic plant colonization and the induction of disease symptoms. Under humid and fresh conditions, dissemination structures are produced by the pathogen on all
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Response of sunflower to different planting dates in cotton based cropping system
International Nuclear Information System (INIS)
Yousaf, M.; Shakoor, A.; Rana, M.A.
2007-01-01
A field study on sunflower (Helianthus annuus L) was conducted for three. years (1991-1993) on different planting dates. Two hybrids (Hysun-33 and PI-6480) were sown on five different dates with 15 days interval from January 15 to March 15 at Cotton Research Station, Multan. Significant higher seed yield of 1880 and 2097 kg ha-1 was obtained when the crop was planted on February 1 and 15 than other treatments. The yield significantly decreased when sunflower was planted on January 15 (1264 kg ha-l), March 1 (1382 kg ha-l) and March 15 (927 kg hall. Maturity period was longest (128 days) of early sown (January 15) and shortest of late sown (March 15) sunflower hybrids. Therefore, it can be concluded that sunflower planted on February 1 to 15 gave higher seed yield as well as allowed enough time for land preparation and thereby, planting of cotton crop in the same field during its regular planting time. (author)
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Shah, Faheem Afzal; Ni, Jun; Chen, Jing; Wang, Qiaojian; Liu, Wenbo; Chen, Xue; Tang, Caiguo; Fu, Songling; Wu, Lifang
2018-01-01
Sapium sebiferum , an ornamental and bio-energetic plant, is propagated by seed. Its seed coat contains germination inhibitors and takes a long time to stratify for germination. In this study, we discovered that the S. sebiferum seed coat (especially the tegmen) and endospermic cap (ESC) contained high levels of proanthocyanidins (PAs). Seed coat and ESC removal induced seed germination, whereas exogenous application with seed coat extract (SCE) or PAs significantly inhibited this process, suggesting that PAs in the seed coat played a major role in regulating seed germination in S. sebiferum . We further investigated how SCE affected the expression of the seed-germination-related genes. The results showed that treatment with SCE upregulated the transcription level of the dormancy-related gene, gibberellins (GAs) suppressing genes, abscisic acid (ABA) biosynthesis and signalling genes. SCE decreased the transcript levels of ABA catabolic genes, GAs biosynthesis genes, reactive oxygen species genes and nitrates-signalling genes. Exogenous application of nordihydroguaiaretic acid, gibberellic acid, hydrogen peroxide and potassium nitrate recovered seed germination in seed-coat-extract supplemented medium. In this study, we highlighted the role of PAs, and their interactions with the other germination regulators, in the regulation of seed dormancy in S. sebiferum .
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Directory of Open Access Journals (Sweden)
Michele Fernanda Bortolini
2011-05-01
Full Text Available O trabalho teve como objetivo avaliar métodos para a superação da dormência de sementes de sucará. As sementes receberam os seguintes tratamentos: 1 testemunha; 2 escarificação mecânica; 3 escarificação mecânica + água/24h; 4 escarificação mecânica + água quente/24h; 5 água quente/24h; 6 ácido sulfúrico (H2SO4/1h; 7 H2SO4/2h; 8 H2SO4/1h + água/24h; 9 H2SO4/30min + água corrente/4h; 10 escarificação mecânica + água corrente/4h. O teste de germinação foi conduzido em rolos de papel Germitest acondicionados em câmara de germinação, à 25°C, com fotoperíodo de 12h por 26 dias. Avaliou-se também o tempo e a velocidade média de germinação. O delineamento experimental foi inteiramente casualizado, com quatro repetições de 25 sementes. O melhor desempenho germinativo foi registrado para as sementes submetidas à escarificação mecânica e química, com médias entre 76 e 98% de germinação, respectivamente, 2,17 a 2,88 dias para tempo médio de germinação e 0,46 a 0,47 sementes/dia para velocidade média de germinação, demonstrando serem estes os melhores métodos para superação da dormência de sementes dessa espécie.The objective of this research was to evaluate methods to overcome dormancy of seeds of Gleditschia amorphoides. For dormancy's overcoming the seeds received the following treatments: 1 control; 2 mechanical scarfication 3 mechanical scarfication + water/24h; 4 mechanical scarfication + hot water/24h; 5 hot water/24h; 6 sulfuric acid (H2SO4/1h; 7 H2SO4/2h; 8 H2SO4/1h + water/24h; 9 H2SO4/30min + flowing water/4h; 10 mechanical scarfication + flowing water/4h. Germination was done in rolls of Germitest conditioned in a germination chamber under 25°C, during 12h for 26 days. Percentage, time and average speed of germination were evaluated. The experimental design was completely casual with 10 treatments, 4 repetitions and 25 seeds. The best results were recorded for treatments with mechanical
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Directory of Open Access Journals (Sweden)
Yana Kazachkova
2016-08-01
Full Text Available The salinization of land is a major factor limiting crop production worldwide. Halophytes adapted to high levels of salinity are likely to possess useful genes for improving crop tolerance to salt stress, as well as providing a food source on marginal lands. However, despite being salt-tolerant plants, the seeds of many halophytes will not germinate on saline soils, yet little is understood regarding biochemical and gene expression changes underlying salt-mediated inhibition of halophyte seed germination. We have used the halophytic Arabidopsis relative model system, Eutrema (Thellungiella salsugineum to explore salt-mediated inhibition of germination. We show that E. salsugineum seed germination is inhibited by salt to a far greater extent than in Arabidopsis, and that this inhibition is in response to the osmotic component of salt exposure. E. salsugineum seeds remain viable even when germination is completely inhibited, and germination resumes once seeds are transferred to non-saline conditions. Moreover, removal of the seed coat from salt-treated seeds allows embryos to germinate on salt-containing medium. Mobilization of seed storage reserves is restricted in salt-treated seeds, while many germination-associated metabolic changes are arrested or progress to a lower extent. Salt-exposed seeds are further characterized by a reduced GA/ABA ratio and increased expression of the germination repressor genes, RGL2, ABI5 and DOG1. Furthermore, a salt-mediated increase in expression of a LATE EMBRYOGENESIS ABUNDANT gene and accretion of metabolites involved in osmoprotection indicates induction of processes associated with stress tolerance, and accumulation of easily mobilized carbon reserves. Overall, our results suggest that salt inhibits E. salsugineum seed germination by inducing a seed state with molecular features of dormancy while a physical constraint to radicle emergence is provided by the seed coat layers. This seed state could facilitate
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Seed yield and oil content of some sunflower ( Helianthus annuus L ...
African Journals Online (AJOL)
This research was carried out to determine the effects of irrigation applied at different growth stages on yield, yield components and oil content of sunflower during 2002 and 2003. Sunflower cultivars Sanbro, Tarsan-1018 and Ozdemirbey were used as materials in the experiment which was designed in a split plot of ...
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DEFF Research Database (Denmark)
Nielsen, Nina Skall; Pedersen, A.; Sandstrøm, B.
2002-01-01
oxidation of fasting and postprandial lipoproteins eighteen males consumed diets enriched with rapeseed oil (RO), olive oil (OO), or sunflower-seed oil (SO) in randomised order for periods of 3 weeks followed by a RO test meal. In the postprandial state the concentrations of cholesterol and triacylglycerol...
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Germination ecophysiology of Annona crassiflora Mart. seeds
Silva, da E.A.A.; Melo, de D.L.B.; Davide, A.C.; Bode, N.; Abreu, G.B.; Faria, J.M.R.; Hilhorst, H.W.M.
2007-01-01
Background and Aims Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species
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Raupp, Frank M; Spring, Otmar
2013-11-06
Orobanche cumana is a serious threat for cultivation of sunflower in Europe and Asia. Germination of the parasite is induced by metabolites released from the host root system. The first germination stimulant from sunflower root exudate was recently identified as dehydrocostus lactone, a sesquiterpene lactone. Bioassay-guided fractionation of root exudates now showed the release of additional sesquiterpene lactones. Besides dehydrocostus lactone, costunolide, tomentosin, and 8-epixanthatin were purified and identified spectroscopically. All four compounds induced germination of O. cumana at nano- to micromolar concentrations. Costunolide and dehydrocostus lactone concentrations above 1 μM reduced the activity, and application of 100 μM inhibited germination irreversibly. Seeds of Phelipanche ramosa could not be induced with costunolide. O. cumana seeds also germinated with GR24, a synthetic strigolactone. No bioactive fraction of sunflower contained compounds of this type. This supports previous findings that sesquiterpene lactones instead of strigolactones trigger the sunflower/O. cumana interaction.
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International Nuclear Information System (INIS)
Ali, H.G.M.
2003-01-01
The present study has been undertaken to evaluated sesame, sunflower and safflower seeds induced by gamma rays, as plant breeding unit, plant research department, radioisotope application division, nuclear research center, atomic energy authority Inshas. the obtained results indicate the following : chemical composition of mutant seeds: the radiation mutation caused a significant increase in both oil and ash content total carbohydrates showed a significant decreased in sesame seeds. radiation mutation induced significant increase in oil and protein content of sunflower and safflower seeds. while the total carbohydrate showed a significant decrease. physiochemical properties of oils extracted mutant seeds: the radiation mutation had no real effect on the refractive index and A.V of oils extracted from control and mutant sesame, sunflower and safflower seeds. while it caused a slight increase in red color and P.V. of sesame oil, the thiobarbituric acid (TBA) value of mutant sesame oil was not alter upon radiation mutation, but it induced a slight decrease in TBA of mutant sunflower and safflower oils. the unsaponifiable matter percentage of oils extracted from mutant sesame, sunflower and safflower seeds were slightly increased by radiation mutation .radiation mutation of seeds had no real effect on the total SFA and USFA of sesame oil. however, radiation mutation induced a remarkable changes in fatty acid profiles of sunflower and safflower oil as total SFA decreased, while USFA increased. Uric acid was only detected in oil extracted from mutant sunflower seeds
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International Nuclear Information System (INIS)
Sizova, L.I.
1976-01-01
The paper comprises the results of the investigation of the storage effect in irradiated seeds on the frequency and the spectrum of structural mutations of chromosomes in normal green plants and in spontaneous chlorophyll mutants of sunflower. The seeds of chlorophyll mutants lutescens and xantha and those of green plants stored for 3 years have been 60 Co gamma-irradiated with doses of 0.5; 1.0; 2.0; 3.0; 5.0 and 10 kr. After the irradiation the seeds have been stored for a year under conventional laboratory conditions. As a result of the post-irradiation storage of seeds for a year the decrease in the proportion of aberrant cells by 3 to 6% at the expense of cells with paired fragments has been observed in green plants. In chlorophyll mutants the storage of seeds after the irradiation results in the 9 to 37% increase of the proportion of aberrant cells at the expense of cells with single and paired bridges and with paired fragments. This gives evidence in favour of the assumption that in spontaneous chlorophyll mutants the processes of the post-irradiation recovery either fail altogether, or proceed at a very low level
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Regulation of abscisic acid metabolism in relation to the dormancy and germination of cereal grains
Directory of Open Access Journals (Sweden)
Justyna Fidler
2015-03-01
Full Text Available Seed dormancy is of particular importance in the cultivation of cereals, as it directly affects the quality of crop yield. If the dormancy period is too short, this may lead to pre-harvest sprouting, whereas a dormancy period that is too long may cause uneven germination; both of these scenarios are associated with economic losses. Most enzymes engaged in the metabolism of abscisic acid (ABA have been identified, and significant progress has been made in understanding the role of this phytohormone in the induction and maintenance of dormancy, mainly as a result of research conducted in Arabidopsis. Much less is known about the metabolism and function of ABA in cereal grains, especially in relation to dormancy and germination. This review focuses on the regulation of ABA metabolism in dormant and non-dormant cereal grains, in both the dry state and upon imbibition. Moreover, this review describes the influence of factors such as after-ripening, light, temperature, nitric oxide, and reactive oxygen species (ROS on the dormancy and germination of cereal grains. These factors, with the exception of ROS, appear to affect the level of dormancy and germination of grains through regulation of ABA metabolism.
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Directory of Open Access Journals (Sweden)
Antenor P. Barbosa
2004-01-01
Full Text Available Este trabalho, teve como objetivo estudar a germinação das sementes de pau-de-balsa (Ochroma lagopus Sw., Bombacaceae em diferentes estágios de maturação aparente dos frutos; a germinação das sementes provenientes de árvores com diferentes diâmetros a altura do peito (DAP e a germinação das sementes tratadas para quebra de dormência. No primeiro experimento, avaliou-se a germinação das sementes dos frutos verdes, verdosos (verde amarelado, negros (fruto fechado e negros deiscentes (fruto aberto com painas expostas. No segundo, a germinação das sementes de árvores da mesma idade e com diferentes DAP's: pequeno (5,4 cm, médio (9,1 cm e grande (13,2 cm. No terceiro, a germinação das sementes com diferentes quebra de dormência: testemunha; água por 24 e 48 horas; água a 80ºC até esfriar; H2SO4 por ½ e 1 minuto com e sem paina; queima da paina em peneira metálica; e semeio de sementes com a paina. As sementes germinaram em gerbox sobre papel de filtro, em câmara de germinação, nas temperaturas de 20ºC, 30ºC e 25ºC, no primeiro, segundo e terceiro experimentos, respectivamente. As sementes de pau-de-balsa germinaram melhor e mais rápido quando coletadas de frutos negros a negros deiscentes, ou quando coletadas de árvores com menor e médio diâmetros, ou quando tratadas com água quente a 80ºC até esfriar, ou com ácido sulfúrico por ½ ou 1 minuto com ou sem paina. Os tratamentos com ácido tem a vantagem de quebrar a dormência da semente e dissolver a paina. As sementes recém colhidas e germinadas não apresentaram dormência tegumentar.The objective of this study was to evaluate the germination of "pau-de-balsa" (Ochroma lagopus Sw., Bombacaceae seed as a function of maturation stages of fruits, the germination of seeds harvested from trees with different diameters at height breast (DBH, and the germination of seed with different treatments to break dormancy. In the first experiment, the germination of seeds
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Medeiros, Maria J; Oliveira, Marciel T; Willadino, Lilia; Santos, Mauro G
2015-12-01
Syagrus coronata, a native palm tree of the Brazilian semi-arid region, exhibits low germinability due to seed dormancy. This study aimed to increase the germinability, analyze the morphology of seedlings and evaluate the performance of young plants under a water deficit. We used immersion in water and gibberellic acid (GA3) as pyrene (seed with endocarp) pre-germination treatments, and we analyzed the water relations, gas exchange, chlorophyll fluorescence and carbon balance components of young plants under drought and rehydration conditions. The immersion of pyrenes in 0.3 mM GA3 solution for 24 h enhanced the emergence and survival of plants and the emergence rate index. The germination of S. coronata is of the remote tubular type, and seedling growth originates with the protrusion of the cotyledon petiole, followed by the subsequent emergence of the root, leaf sheaths and eophyll. The plants exhibited high tolerance to no irrigation for 37 days, which was attributed to strong stomatal control, a higher proportion of energy dissipation and a higher content of photoprotective pigments. Despite the reduced stomatal conductance (regardless of soil water availability), the photosynthetic rate remained high throughout the day, which indicated a low correlation between these two parameters. After rehydration, we observed that both the leaf water content and photosynthesis recovered, which showed an absence of irreversible damage of the photosynthetic apparatus. The use of 0.3 mM GA3 is recommended as a treatment for overcoming seed dormancy in this species. Young S. coronata plants showed high tolerance during drought and resilience after rehydration by adjusting their leaf metabolism, which could explain the endemism of this species in semi-arid regions and its ability to remain evergreen throughout the year. Furthermore, with high photosynthetic rate in the most favorable time of day, even under drought stress. Copyright © 2015 Elsevier Masson SAS. All rights
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Davis, Adam S; Fu, Xianhui; Schutte, Brian J; Berhow, Mark A; Dalling, James W
2016-10-01
Soil seedbanks drive infestations of annual weeds, yet weed management focuses largely on seedling mortality. As weed seedbanks increasingly become reservoirs of herbicide resistance, species-specific seedbank management approaches will be essential to weed control. However, the development of seedbank management strategies can only develop from an understanding of how seed traits affect persistence.We quantified interspecific trade-offs among physiological, chemical, and physical traits of weed seeds and their persistence in the soil seedbank in a common garden study. Seeds of 11 annual weed species were buried in Savoy, IL, from 2007 through 2012. Seedling recruitment was measured weekly and seed viability measured annually. Seed physiological (dormancy), chemical (phenolic compound diversity and concentration; invertebrate toxicity), and physical traits (seed coat mass, thickness, and rupture resistance) were measured.Seed half-life in the soil ( t 0.5 ) showed strong interspecific variation ( F 10,30 = 15, p central role of seed dormancy in controlling seed persistence.A quantitative comparison between our results and other published work indicated that weed seed dormancy and seedbank persistence are linked across diverse environments and agroecosystems. Moreover, among seedbank-forming early successional plant species, relative investment in chemical and physical seed defense varies with seedbank persistence. Synthesis and applications . Strong covariance among weed seed traits and persistence in the soil seedbank indicates potential for seedbank management practices tailored to specific weed species. In particular, species with high t 0.5 values tend to invest less in chemical defenses. This makes them highly vulnerable to physical harvest weed seed control strategies, with small amounts of damage resulting in their full decay.
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Directory of Open Access Journals (Sweden)
Faheem Afzal Shah
2018-04-01
Full Text Available Sapium sebiferum, an ornamental and bio-energetic plant, is propagated by seed. Its seed coat contains germination inhibitors and takes a long time to stratify for germination. In this study, we discovered that the S. sebiferum seed coat (especially the tegmen and endospermic cap (ESC contained high levels of proanthocyanidins (PAs. Seed coat and ESC removal induced seed germination, whereas exogenous application with seed coat extract (SCE or PAs significantly inhibited this process, suggesting that PAs in the seed coat played a major role in regulating seed germination in S. sebiferum. We further investigated how SCE affected the expression of the seed-germination-related genes. The results showed that treatment with SCE upregulated the transcription level of the dormancy-related gene, gibberellins (GAs suppressing genes, abscisic acid (ABA biosynthesis and signalling genes. SCE decreased the transcript levels of ABA catabolic genes, GAs biosynthesis genes, reactive oxygen species genes and nitrates-signalling genes. Exogenous application of nordihydroguaiaretic acid, gibberellic acid, hydrogen peroxide and potassium nitrate recovered seed germination in seed-coat-extract supplemented medium. In this study, we highlighted the role of PAs, and their interactions with the other germination regulators, in the regulation of seed dormancy in S. sebiferum.
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TIME REDUCTION FOR SURINAM GRASS SEED GERMINATION TEST
Directory of Open Access Journals (Sweden)
Camila de Aquino Tomaz
2015-10-01
Full Text Available ABSTRACTThe period for the germination test of Surinam grass seeds established by the Rules for Seeds Testing is 28 days, considered too lengthy by producers, venders, and seed analysis laboratories. So, the objective of this research was to evaluate the possibility of reducing the time for the germination test of Surinam grass seeds and to establish a method for dormancy breaking and the ideal temperature. Ten seed lots were submitted to the following treatments to overcome seed dormancy: control; substrate moistening with 0.2% KNO3; and scarification with sulfuric acid (98% 36 N for 15 minutes. After the treatments, the lots were submitted to seed water content, germination and tetrazolium tests. During the germination test, conducted with four replicates of 100 seeds per treatment for 28 days, two conditions of alternating temperatures (20-35 °C and 15-35 °C with 8 hours of light were tested. Attempting to determine the test end date, daily counts of the number of normal seedlings were made and for each lot, treatment, and temperature, a growth curve for the evaluation of germination was adjusted. The segmented regression model parameter estimations were calculated for each treatment. The germination test of Braquiaria decumbensseeds may be evaluated in 12 days after sowing using alternating temperatures of 20-35 °C and without any treatment to overcome dormancy.
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Effect of ethanol and plant growth regulators on termination of potato microtuber dormancy
Directory of Open Access Journals (Sweden)
Wróbel Sławomir
2015-12-01
Full Text Available The duration of dormancy varies significantly among cultivars, but even short dormancy can limit usage of potato microtubers for seed production. The aim of the research was to test efficacy of dormancy breaking by treatment with an aqueous solution of ethyl alcohol, saccharose, gibberellic acid and kinetin (ethanol treatment in comparison to treatment with aqueous solution of thiourea, daminozide and gibberellic acid (standard treatment. Prolonging the period of microtuber production at the in vitro stage significantly favored the short-ening of the dormancy and facilitated its breaking. While the standard treatment had the strongest effect, the ethanol treatment was slightly less efficient. The statistically significant differences were only observed during the first 13 days after the microtuber treatment. After that time, efficacy of ethanol and standard treatments was similar to control treatment with water. The investigated treatments had no effect on the natural decrease of ABA level in microtubers.
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Cousens, Roger D; Young, Kenneth R; Tadayyon, Ali
2010-01-01
Dry fruits remain around the seeds at dispersal in a number of species, especially the Brassicaceae. Explanations for this vary, but usually involve mechanisms of innate dormancy. We speculate that, instead, a persistent fruit may give additional protection through control of dehydration, to species growing in arid or Mediterranean environments where water is sporadic. X-rays and weight measurements were used to determine the extent to which Raphanus raphanistrum seeds within mature fruits imbibe water, and germination tests determined the roles of the fruit and seed coat in seed dormancy. Rates of water uptake and desiccation, and seedling emergence were compared with and without the fruit. Finally, germinability of seeds extracted from fruits was determined after various periods of moist conditions followed by a range of dry conditions. Most seeds rapidly take up water within the fruit, but they do not fully imbibe when compared with naked seeds. The seed coat is more important than the dry fruit wall in maintaining seed dormancy. The presence of a dry fruit slows emergence from the soil by up to 6-8 weeks. The fruit slows the rate of desiccation of the seed to a limited extent. The presence of the fruit for a few days during imbibition somehow primes more seeds to germinate than if the fruit is absent; longer moist periods within the pod appear to induce dormancy. The fruit certainly modifies the seed environment as external conditions change between wet and dry, but not to a great extent. The major role seems to be: (a) the physical restriction of imbibition and germination; and (b) the release and then re-imposition of dormancy within the seed. The ecological significance of the results requires more research under field conditions.
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NUTRIENT CONTENT IN SUNFLOWERS IRRIGATED WITH OIL EXPLORATION WATER
Directory of Open Access Journals (Sweden)
ADERVAN FERNANDES SOUSA
2016-01-01
Full Text Available Irrigation using produced water, which is generated during crude oil and gas recovery and treated by the exploration industry, could be an option for irrigated agriculture in semiarid regions. To determine the viability of this option, the effects of this treated water on the nutritional status of plants should be assessed. For this purpose, we examined the nutritional changes in sunflowers after they were irrigated with oil - produced water and the effects of this water on plant biomass and seed production. The sunflower cultivar BRS 321 was grown for three crop cycles in areas irrigated with filtered produced water (FPW, reverse osmosis - treated produced water (OPW, or ground water (GW. At the end of each cycle, roots, shoots, and seeds were collected to examine their nutrient concentrations. Produced water irrigation affected nutrient accumulation in the sunflower plants. OPW irrigation promoted the accumulation of Ca, Na, N, P, and Mg. FPW irrigation favored the accumulation of Na in both roots and shoots, and biomass and seed production were negatively affected. The Na in the shoots of plants irrigated with FPW increased throughout the three crop cycles. Under controlled conditions, it is possible to reuse reverse osmosis - treated produced water in agriculture. However, more long - term research is needed to understand its cumulative effects on the chemical and biological properties of the soil and crop production.
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Effect of pre-germination treatments on the dormancy breaking and ...
African Journals Online (AJOL)
The demand for bitter kola (Garcinia kola) is high in Nigeria market but the population of the species is low both in the wild and home gardens. Rapid deforestation, heavy exploitation in the natural forest and difficulties associated with its germination occasioned by seed dormancy have been blamed. The study on ...
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Yazdanpanah, Farzaneh; Hanson, Johannes; Hilhorst, Henk W.M.; Bentsink, Leónie
2017-01-01
Background: Seed dormancy, defined as the incapability of a viable seed to germinate under favourable conditions, is an important trait in nature and agriculture. Despite extensive research on dormancy and germination, many questions about the molecular mechanisms controlling these traits remain
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Improving germination of Chionanthus virginicus L. seed by using gibberellic acid (GAZ
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Grbić Mihailo
2005-01-01
Full Text Available The aim of this experiment was to explore effects of gibberellic acid on Chionanthus virginicus L. seed germination. The species has great horticultural values but due to problem in propagation it is rarely used. The seed possesses double dormancy: egzo and endo dormancy. Gibberellin has shown helpful in overcoming endo dormancy which is confirmed with this species. Different concentrations of GA3 had different influence. The lower one has shown stimulative effects while the higher one has shown the inhibitor effects. It is also confirmed that endocarp prevents germination.
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Sunflower (Helianthus annuus L.).
Radonic, Laura M; Lewi, Dalia M; López, Nilda E; Hopp, H Esteban; Escandón, Alejandro S; Bilbao, Marisa López
2015-01-01
Sunflower (Helianthus annuus L.) is still considered as a recalcitrant species to in vitro culture and transformation in spite of the publication of different protocols. Here we describe a routine transformation system of this crop which requires mature HA89 genotype seeds and Agrobacterium tumefaciens EHA105 strain for gene delivery, being both easily available. Selection of transformed shoots depends on root development in kanamycin-selective media, instead of shoot color, avoiding selection of escapes. The establishment of this protocol proved successful for the incorporation of both reporter and agronomic important genes and also for the evaluation of the specific expression patterns of different promoters in transgenic sunflower plants. Stable expression of the incorporated transgenes was confirmed by RT-PCR and GUS reporter gene visualization. Stable inheritance of transgenes was successfully followed until T2 generation in several independent lines.
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Gascuel, Quentin; Buendia, Luis; Pecrix, Yann; Blanchet, Nicolas; Muños, Stéphane; Vear, Felicity; Godiard, Laurence
2016-01-01
Plasmopara halstedii is an obligate biotrophic oomycete causing downy mildew disease on sunflower, Helianthus annuus, an economically important oil crop. Severe symptoms of the disease (e.g., plant dwarfism, leaf bleaching, sporulation and production of infertile flower) strongly impair seed yield. Pl resistance genes conferring resistance to specific P. halstedii pathotypes were located on sunflower genetic map but yet not cloned. They are present in cultivated lines to protect them against downy mildew disease. Among the 16 different P. halstedii pathotypes recorded in France, pathotype 710 is frequently found, and therefore continuously controlled in sunflower by different Pl genes. High-throughput sequencing of cDNA from P. halstedii led us to identify potential effectors with the characteristic RXLR or CRN motifs described in other oomycetes. Expression of six P. halstedii putative effectors, five RXLR and one CRN, was analyzed by qRT-PCR in pathogen spores and in the pathogen infecting sunflower leaves and selected for functional analyses. We developed a new method for transient expression in sunflower plant leaves and showed for the first time subcellular localization of P. halstedii effectors fused to a fluorescent protein in sunflower leaf cells. Overexpression of the CRN and of 3 RXLR effectors induced hypersensitive-like cell death reactions in some sunflower near-isogenic lines resistant to pathotype 710 and not in susceptible corresponding lines, suggesting they could be involved in Pl loci-mediated resistances. PMID:28066456
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Quentin Gascuel
2016-12-01
Full Text Available Plasmopara halstedii is an obligate biotrophic oomycete causing downy mildew disease on sunflower, Helianthus annuus, an economically important oil crop. Severe symptoms of the disease (e.g. plant dwarfism, leaf bleaching, sporulation and production of infertile flower strongly impair seed yield. Pl resistance genes conferring resistance to specific P. halstedii pathotypes were located on sunflower genetic map but yet not cloned. They are present in cultivated lines to protect them against downy mildew disease. Among the 16 different P. halstedii pathotypes recorded in France, pathotype 710 is frequently found, and therefore continuously controlled in sunflower by different Pl genes. High-throughput sequencing of cDNA from P. halstedii led us to identify potential effectors with the characteristic RXLR or CRN motifs described in other oomycetes. Expression of six P. halstedii putative effectors, five RXLR and one CRN, was analysed by qRT-PCR in pathogen spores and in the pathogen infecting sunflower leaves and these six effectors were selected for functional analyses. We developed a new method for transient expression in sunflower plant leaves and showed for the first time subcellular localization of P. halstedii effectors fused to a fluorescent protein in sunflower leaf cells. Overexpression of the CRN and of 3 RXLR effectors induced hypersensitive-like cell death reactions in some sunflower near-isogenic lines resistant to pathotype 710 and not in susceptible corresponding lines, suggesting they could be involved in Pl loci-mediated resistances.
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Epicotyl dormancy of tree peony as an oil plant broken by cyanamide
Xu, Jiajie; Gong, Mingfu; Liu, Fang; Wu, Sanlin; Liu, Xiaojie; Zhang, Ya; Xu, Gaoyu
2018-04-01
This test materials is `feng Dan', an oil peony, or tree peony as an oil plant, growing in Yangtze river basin. Impact of cyanamide on oil peony epicotyl dormancy was represented with germination rate of peony feeds, a-amylase activity, soluble sugar content, soluble protein content and peroxidase (POD) activity. Results showed that hypocotyls' dormancy of peony seeds was significant breaken by 0.3% cyanamide concentration. Alpha-amylase activity, soluble sugar content, soluble protein content and POD activity in 0.3% cyanamide concentration treatment was significantly higher than other treatments. There was no significant difference between the rest treatments.
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Tahaei, Amirreza; Soleymani, Ali; Shams, Majid
2016-09-01
Reduced seed germination is among the most important factors adversely affecting crop stand and subsequent plant growth. Fennel (Foeniculum vulgare Mill) is an important medicinal plant with poor seed germination rate, occasionally. It is accordingly pertinent to find methods which can enhance fennel seed germination and remove the barriers of dormancy breaking. The present experiments studied the effects of two different priming (cold moist stratification and osmopriming) and 14 dormancy breaking techniques (hormonal, osmopriming, biopriming, chemical priming, and hydropriming) on the seed germination and seedling growth of two different fennel genotypes under growth chamber conditions. In the first and second experiment, the priming techniques including the time lengths of cold moist stratification (0, 15, 30, and 45 days) and the concentrations of polyethylene glycol 6000 (PEG6000, osmopriming at -0.99, -1.35, and -2.33 MPa) were used as the main plots. However, in both experiments, the dormancy breaking techniques and fennel genotypes were factorially combined and used as the subplots. Different seed- and seedling-related parameters including germination (%), plumule, radicle and seedling length, average germination time, rate and homogeneity of germination, and seed vigor index were determined. Both priming techniques were efficient on the enhancement of seed germination and seedling growth. Among the dormancy breaking techniques, Aminol Forte (biopriming), kadostim (biopriming), benzyl adenine + kinetin (biopriming), distilled water (hydropriming), gibberellin + kinetin (hormonal priming), and benzyl adenine + kinetin + gibberellin (biopriming) were the most effective ones. The related concentrations were equal to 100 mg/l, 10(-5) M, and 0.4 %. The fennel genotypes reacted significantly different under priming conditions. It is possible to enhance seed germination and seedling growth of fennel using priming and dormancy breaking
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Ronaldo Oliveira Sales
2013-01-01
Full Text Available The objective of the study is to evaluate meat quality from Ile de France lamb fed diets supplemented with sunflower seeds and vitamin E. Thirty-two lamb weighing initially 15kg were housed in individual stalls and slaughtered when body weight reached 32kg. The treatments consisted of four experimental diets: D1 sugarcane + concentrate without sunflower seeds; D2 sugarcane + concentrate with sunflower seeds; D3 sugarcane + concentrate without sunflower seeds plus 1000mg vitamin E kg-1 diet dry matter (DM; and D4 sugarcane + concentrate with sunflower seeds and 1000mg vitamin E kg-1 diet DM. The parameters temperature, pH, color, cooking loss, shear force and water holding capacity were determined at maturation times of 0, 7 and 14 days on the Longissimus dorsi muscle. Qualitative characteristics of the meat were not affected by the sunflower seed combined with vitamin E diet; however, pH 24 hours was affected (P0.05 by diet or maturation times. On the other hand, shear force and water holding capacity were significantly affected (PO objetivo deste estudo foi avaliar a qualidade da carne de cordeiros Ile de France alimentados com dietas contendo grãos de girassol e vitamina E. Trinta e dois cordeiros pesando inicialmente 15kg foram alojados em baias individuais e abatidos ao atingir 32kg de peso corporal. Os tratamentos consistiram de quatro dietas experimentais: D1 cana-de-açúcar + concentrado sem grãos de girassol; D2 cana-de-açúcar + concentrado com grãos de girassol; D3 cana-de-açúcar + concentrado grãos de girassol, mais 1000mg de vitamina E kg-1 de matéria seca (MS da dieta; e D4 cana-de-açúcar + concentrado com grãos de girassol e 1000mg de vitamina E dieta kg-1 de MS. Os parâmetros temperatura, pH, cor, perda de peso ao cozimento, força de cisalhamento e capacidade de retenção de água foram determinados nos tempos de maturação de 0, 7 e 14 dias no músculo Longissimus dorsi. As características qualitativas da carne n
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Gene regulation in seeds : insights into translational dynamics
Bai, B.
2016-01-01
Seeds are unique structures in the plant life cycle. The variation in the timing of seed maturation, dispersion, and the establishment of seed dormancy and longevity, increases the chances of plant survival and enlarge the distance that plants could disperse in the natural habitat. Seeds contain
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Trichoderma harzianum elicits induced resistance in sunflower challenged by Rhizoctonia solani.
Singh, B N; Singh, A; Singh, B R; Singh, H B
2014-03-01
To investigate the efficacy of Trichoderma harzianum NBRI-1055 (denoted as 'T-1055') in suppression of seedling blight of sunflower caused by Rhizoctonia solani Kühn and their impact on host defence responses. T-1055 was applied as seed treatment, soil application and combined application (seed treatment + soil application). Higher protection afforded by combined application of T-1055 was associated with the marked induction of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), peroxidase (PO) and cinnamyl alcohol dehydrogenase (CAD) activities. The activities of PAL and PPO reached maximum at 10 days after sowing (DAS), while PO and CAD levels reached maximum at 12 DAS. This was further supported by the accumulation of total phenolic content that showed an increase up to threefold at 14 DAS. In addition, HPLC analysis revealed that the contents of ferulic and p-coumaric acids increased by 6·3 and 4·6 times, respectively, at 14 DAS. Amount of gallic acid was also little more than double. Lignin deposition in sunflower root increased by 2·7, 3·4 and 3·7 times through combined application of T-1055 at 16, 18 and 20 DAS, respectively. Combined application also increased the accumulation of PR-2 and PR-3 proteins by 3·3 and 3·9 times, respectively, at 12 DAS in followed by seed treatment alone. The combined application of T-1055 triggered defence responses in an enhanced level in sunflower than the soil and seed alone and provided better protection against Rhizoctonia seedling blight. Rhizospheric fungal bioagent 'T-1055' can enhance protection in sunflower against the R. solani pathogen through augmented elicitation of host defence responses. © 2013 The Society for Applied Microbiology.
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Manoel Xavier de Oliveira Júnior
2010-06-01
Full Text Available Com o objetivo de avaliar métodos de superação de dormência em sementes de maracujá-do-mato (P. cincinnata Mast., foi conduzido o experimento em casa de vegetação, na Universidade Estadual do Sudoeste do Estado da Bahia - UESB, Câmpus de Vitória da Conquista - BA, Brasil. O delineamento experimental foi o inteiramente casualizado, com sete tratamentos e três repetições, sendo 50 sementes por parcela: T1= sementes secas à sombra (Testemunha; T2= sementes secas ao sol (35 ±1ºC; T3= sementes secas à sombra com escarificação em lixa; T4= sementes secas à sombra tratadas com captana (0,2%; T5= sementes secas ao sol (35 ±1ºC com escarificação em lixa; T6= sementes secas à sombra aquecidas em banho-maria por 5 minutos, a 50ºC; T7= sementes secas à sombra aquecidas em banho-maria por 5 minutos, a 80ºC. As características avaliadas foram: porcentagem de germinação; porcentagem de emergência; índice de velocidade de emergência; altura das plântulas; diâmetro do caule; número de folhas; comprimento da raiz pivotante; massa da matéria seca total. Os resultados obtidos e analisados permitiram concluir que os melhores tratamentos para superação de dormência são o T3 (sementes secas à sombra com escarificação em lixa e T6 (sementes secas à sombra aquecidas em banho-maria por 5 minutos, a 50ºC.With the objective of evaluating the effect of different methods of dormancy break down on P.cincinnata Mast. seeds, a research was carried out in greenhouse at Bahia State University, Campus of Vitória da Conquista county, Bahia State, Brazil. The experimental design was a interely randomized blocks, composed of seven treatments and three replications, (T1-seeds dried in shade; T2-seeds dried in the sun; T3-seeds dried in shade followed by scarification; T4-seeds dried in shade and treated with captana (0,2%; T5-seeds dried in the sun followed by scarification; T6-seeds dried in shade and treated with hot water at 50ºC; T7
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International Nuclear Information System (INIS)
Baraich, A.A.K.; Gandahi, A.W.
2016-01-01
The sunflower (Helianthus annuus L.) has been recognized as a crop with high potentials that can successfully meet future oil requirements of the country. Formulation of micronutrients (MN) based fertilizer, in terms of application rate and method, and uptake of MN by sunflower has the ability not only to ensure nutrients availability to plants particularly in MN-limiting environments but also can manipulate the environmental hazards associated with over inorganic fertilization. To support this view, clear experimental evidence is still lacking. In addition, the current experiments aimed to evaluate the influence of MN and its method of application on yield and yield components of sunflower cultivars/hybrids. Three sunflower cultivars (HO-1, Hysun-39 and Ausigold-62) along with three MN (Z, B and Fe) and two application methods (soil and foliar) were used in the experiment. Three Zn application rate (3, 5 and 8 kg ha-1) along with 0.75 kg ha-1 B and 0.30 kg Fe ha-1 were used in four combinations such as 0-0-0, 0-0.75-0.30, 0-0.75-0.30, 3-0.75-0.30, 5-0.75-0.30, 8-0.75-0.30 kg Z, B and Fe ha-1, respectively. A control (no MN) treatment was also included for comparison. Two year averaged study exhibited that foliar application of Zn, B and Fe at rate of 8-0.30-0.75 kg ha-1 increased stem girth, head diameter, number of seeds head-1, seed weight head-1, seed index, oil content and seed yield by 21%, 27%, 13%, 34%, 19%, 24 and 31%, respectively over control. Among cultivars/hybrids, the hybrids HO-1 and Hysun-39 had taller plants, seed weight head-1, seeds head-1 and earlier in flowering and maturity. Flowering and maturity was delayed in Ausi Gold-62 with higher seed index and oil content. It is concluded that foliar application of micronutrients at the rate of 8+0.75+0.30 Zn, B and Fe kg ha-1 had substantially improved yield and yield related traits of sunflower cultivars HO-1, Hysun-39 and Ausi gold-62. (author)
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Leff, Jonathan W; Lynch, Ryan C; Kane, Nolan C; Fierer, Noah
2017-04-01
Root and rhizosphere microbial communities can affect plant health, but it remains undetermined how plant domestication may influence these bacterial and fungal communities. We grew 33 sunflower (Helianthus annuus) strains (n = 5) that varied in their extent of domestication and assessed rhizosphere and root endosphere bacterial and fungal communities. We also assessed fungal communities in the sunflower seeds to investigate the degree to which root and rhizosphere communities were influenced by vertical transmission of the microbiome through seeds. Neither root nor rhizosphere bacterial communities were affected by the extent of sunflower domestication, but domestication did affect the composition of rhizosphere fungal communities. In particular, more modern sunflower strains had lower relative abundances of putative fungal pathogens. Seed-associated fungal communities strongly differed across strains, but several lines of evidence suggest that there is minimal vertical transmission of fungi from seeds to the adult plants. Our results indicate that plant-associated fungal communities are more strongly influenced by host genetic factors and plant breeding than bacterial communities, a finding that could influence strategies for optimizing microbial communities to improve crop yields. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
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Seed dormancy and germination : light and nitrate
Hilhorst, H.W.M.
1990-01-01
One of the most important aspects of the life cycle of seed plants is the formation and development of seeds on the motherplant and the subsequent dispersal. An equally important element of the survival strategy is the ability of seeds to prevent germination in unfavorable
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Directory of Open Access Journals (Sweden)
Ana Claudia da Silva
2013-03-01
Full Text Available The coral tree (Erythrina velutina Willd. is an arboreal species that occurs in northeast Brazil and is used in popular medicine to fight cough, asthma, oral diseases, nervous breakdowns, muscle aches and fevers. The process of formation of seedlings of the species is difficult because of the occurrence of seed dormancy. The aim of this study was to evaluate the effect of different methods for overcoming dormancy in seeds of the coral tree stored in different conditions and periods. The experimental design was completely randomized in factorial scheme 5 x 2 (methods for overcoming dormancy and storage types, in four replicates of 25 seeds. The methods used were (S1 control, (S2 scarification opposite the micropyle; (S3 by the scarification micropyle; (S4 seeds immersed in water at 80 °C for five minutes and (S5 seeds immersed in water at 100 °C for two minutes. The storage types were for 25 months at cold chamber and for a month at the laboratory environment. The characteristics evaluated were emergence percentage (PE, time of emergence (TM, shoot length (CPA and root (CR, diameter (D, leaf number (NF, dry biomass of roots (MSPA and of shoots (MSR of seedlings. The emergence percentage was low in treatments S1, S4 and S5 and the seeds stored for one month were more affected when immersed in hot water. The highest values of CPA, CR, MSPA and NF treatments were observed in S2 and S3, which occurred in the lowest average time of emergence. The tegument dormancy of seeds of Erythrina velutina is overcome by scarification with sandpaper on the end opposite the micropyle or next to it. The seed dormancy is not affected by the types of storage and is not overcome by immersion in hot water. O mulungu (Erythrina velutina Willd. é uma espécie arbórea que ocorre no Nordeste brasileiro utilizada na medicina popular no combate a tosse, asma, afecções bucais, crises nervosas, dores musculares e febres. O processo de formação de mudas da espécie
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Auld, Tony D.; Keith, David A.; Hui, Francis K. C.; Ooi, Mark K. J.
2016-01-01
Dormancy and germination requirements determine the timing and magnitude of seedling emergence, with important consequences for seedling survival and growth. Physiological dormancy is the most widespread form of dormancy in flowering plants, yet the seed ecology of species with this dormancy type is poorly understood in fire-prone vegetation. The role of seasonal temperatures as germination cues in these habitats is often overlooked due to a focus on direct fire cues such as heat shock and smoke, and little is known about the combined effects of multiple fire-related cues and environmental cues as these are seldom assessed in combination. We aimed to improve understanding of the germination requirements of species with physiological dormancy in fire-prone floras by investigating germination responses across members of the Rutaceae from south eastern Australia. We used a fully factorial experimental design to quantify the individual and combined effects of heat shock, smoke and seasonal ambient temperatures on germination of freshly dispersed seeds of seven species of Boronia, a large and difficult-to-germinate genus. Germination syndromes were highly variable but correlated with broad patterns in seed morphology and phylogenetic relationships between species. Seasonal temperatures influenced the rate and/or magnitude of germination responses in six species, and interacted with fire cues in complex ways. The combined effects of heat shock and smoke ranged from neutral to additive, synergistic, unitive or negative and varied with species, seasonal temperatures and duration of incubation. These responses could not be reliably predicted from the effect of the application of single cues. Based on these findings, fire season and fire intensity are predicted to affect both the magnitude and timing of seedling emergence in wild populations of species with physiological dormancy, with important implications for current fire management practices and for population
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H.T.R. Amaro
2012-01-01
Full Text Available O objetivo do trabalho foi avaliar a eficiência de tratamentos pré-germinativos na superação da dormência de sementes de manjericão, produzidas no Horto de Plantas Medicinais da Unimontes, em fevereiro de 2011. Foram realizadas as seguintes determinações para avaliação da qualidade fisiológica das sementes: teor de água, germinação, primeira contagem de germinação, emergência de plântulas e índice de velocidade de emergência. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições de 50 sementes por tratamento, sendo T1- testemunha; T2 - pré esfriamento das sementes em câmara tipo BOD sob temperatura de 10ºC por 4 dias; T3 - embebição das sementes em água destilada por 24 horas; T4 - embebição das sementes em solução contendo KNO3 a 0,2 % por 5 minutos e T5 - sementes submetidas em água destilada a temperatura de 70ºC por 5 minutos. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste Scott - Knott a 5% de probabilidade. O tratamento pré esfriamento em câmara tipo BOD a 10ºC por 4 dias reduz a dormência e promove incrementos na qualidade fisiológica das sementes do manjericão.Aiming in order to assess the effectiveness of treatments to overcome dormancy in seeds of basil, an experiment was conducted at the Laboratory of Seed Analysis of Unimontes. Following determinations were performed to evaluate the physiological quality of seeds, water content, germination, first count germination, seedling emergence and emergence speed index. The experimental design was completely randomized design with four replications of 50 seeds per treatment, which consisted of: T1 - control, T2 - pre-cooling of the seed chamber BOD at a temperature of 10ºC for 4 days, T3 - soaking the seeds in water distilled for 24 hours, T4 - soaking the seeds in a solution containing 0,2% for 5 minutes and T5 - submitted seeds in distilled water at 70ºC for 5 minutes. Data
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Dormancy cycling in seeds: mechanisms and regulation
Claessens, S.M.C.
2012-01-01
The life cycle of most plants starts, and ends, at the seed stage. In most species mature seeds are shed and dispersed on the ground. At this stage of its life cycle the seed may be dormant and will, by definition, not germinate under favourable conditions (Bewley, 1997).
Seasonal
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S. E. Meyer; M. Masi; S. Clement; T. L. Davis; J. Beckstead
2015-01-01
Pyrenophora semeniperda, an important pathogen in Bromus tectorum seed banks in semi-arid western North America, exhibits >4-fold variation in mycelial growth rate. Host seeds exhibit seasonal changes in dormancy that affect the risk of pathogen-caused mortality. The hypothesis tested is that contrasting seed dormancy phenotypes select for contrasting strategies...
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Kanti, Varvara; Günther, Malise; Stroux, Andrea; Sawatzky, Sabine; Henrich, Wolfgang; Abou-Dakn, Michael; Blume-Peytavi, Ulrike; Garcia Bartels, Natalie
2017-12-01
Skin care influences skin barrier function during the first postnatal weeks. Although the use of natural oils in preterms has been investigated, there are currently no data comparing the effect of sunflower oil to an emollient on barrier development in healthy term newborns. In a prospective, randomized clinical study, 50 healthy full-term newborns aged ≤72 h were randomly assigned to two groups: group baby lotion (L, n=22) and sunflower seed oil (SSO, n=24). The skin barrier function was evaluated in three anatomical areas (front, abdomen, and thigh) by noninvasive assessment of transepidermal water loss (TEWL), stratum corneum hydration (SCH), sebum, and skin pH at inclusion and after five weeks. In both groups, skin pH decreased and SCH increased statistically significantly in all measured areas at W5 compared to baseline. TEWL decreased statistically significantly on the forearm in both groups, on the upper leg in group L, and on the abdomen in group SSO. Both skin care regimes did not harm skin barrier function adaptation in healthy term neonates during the first five weeks of life. © 2017 Wiley Periodicals, Inc.
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Main aspects of sunflower production in Brazil
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Castro Cesar
2018-01-01
Full Text Available Sunflower is one of the most important oilseed crops in the world, since its grains have high oil content (38% to 50%, primarily used for the production of high quality oil. The production of sunflower increases the supply of protein meal for animal feeding, which enables the increase of protein production, more specifically meat, eggs and milk. Grain production systems in Brazil have peculiarities, since two to three different crops are grown in a special arrangement, in the same area and year. Notwithstanding the small cultivated area in Brazil of 62.3 thousand hectares, sunflower is used in succession or rotation with other grain crops such as soybean or maize, showing an enormous potential for expansion and can be cultivated from latitudes 33°S to 5°N, especially in the Brazilian Cerrado biome. Sunflower cultivation in succession to soybean as a second summer crop can also reduce environmental impacts because of the more efficient usage of production factors, such as land and sharing of agricultural inputs, machinery, infrastructure and workforce. The success of establishing the sunflower is associated with the adequate management of soil fertility, use of cultivars adapted to different environments, plant arrangement, seed quality and adequate phytosanitary management, among other factors. It also needs strategic actions, planning and, long-term research and technology diffusion.
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Cibele Chalita Martins
2008-07-01
Full Text Available O objetivo do trabalho foi identificar métodos para superar a dormência e promover a germinação de sementes de Stryphnodendron adstringens e Stryphnodendron polyphyllum. Sementes de ambas as espécies foram submetidas aos seguintes tratamentos desuperação de dormência: testemunha, escarificação mecânica (lixa número 220, H2O quente (temperatura inicial de 87oC por 5 e por 15 minutos, escarificação química com H2SO4 (95% por 30, 45, 60, 75, 90 e 105 minutos, choque térmico 1 (0oC e 50% UR por 1h e após imersão em água por 10 min. Ti=85oC Tf=57oC, choque térmico 2 (40oC e 40%UR por 6 h e após imersão em água por 10 min. Ti=0oC Tf=3oC, choque térmico 3 (40oC e 40% UR por 6h e após imersão em água por 10 min Ti=25oC Tf=25oC. Conclui-se que sementes pertencentes ao mesmo gênero, mas de espécies diferentes, respondem de forma diversa a alguns tratamentos de superação de dormência. Para ambas as espécies, a escarificação das sementes com H2SO4 (45 minutos ou lixa são métodos que podem ser utilizados com máxima eficiência para a superação da dormência e promoção da germinação.The aim of this research was to identify methods for breaking dormancy and promoting germination of Stryphnodendron adstringens and S. polyphyllum seeds. Seeds of both species were submitted to the following treatments for breaking dormancy: control; mechanical scarification (sandpaper number 220; hot water (initial temperature of 87°C for 5 and 15 minutes; chemical scarification with H2SO4 (95% for 30, 45, 60, 75, 90 and 105 minutes; thermalshock 1 (0°C and 50% RH for 1 h and thereafter 10 minutes into water Ti=85°C, Tf=57°C; thermic shock 2 (40°C and 40% RH for 6 h and thereafter 10 minutes into water, Ti=0°C, Tf=3°C; thermal shock 3 (40°C and 40% RH for 6h and thereafter 10 minutes into water, Ti=25°C, Tf=25°C. We concluded that seeds belonging to samegenus but from different species answered differently to some treatments
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Mariana-Atena Poiana
2012-07-01
Full Text Available This study was performed to investigate the effectiveness of grape seed extract (GSE compared to butylated hydroxytoluene (BHT on retarding lipid oxidation of sunflower oil subjected to convection and microwave heating up to 240 min under simulated frying conditions. The progress of lipid oxidation was assessed in terms of peroxide value (PV, p-anisidine value (p-AV, conjugated dienes and trienes (CD, CT, inhibition of oil oxidation (IO and TOTOX value. In addition, total phenolic content (TP was evaluated in samples before and after heating in order to assess the changes in these compounds relative to the extent of lipid oxidation. The results of this study highlight that GSE showed a significantly inhibitory effect on lipid oxidation during both treatments, although to a different extent. This ability was dose-dependent; therefore, the extent of lipid oxidation was inversely related to GSE level. Convective heating, respective microwave exposure for 240 min of samples supplemented by GSE to a level of 1000 ppm, resulted in significant decreases of investigated indices relative to the control values as follows: PV (48%; 30%, p-AV (29%; 40%, CD (45%; 30%, CT (41%; 36%, TOTOX (35%; 37%. GSE to a level of 600–800 ppm inhibited the lipid oxidation in a similar manner to BHT. These results suggested that GSE can be used as a potential natural extract for improving oxidative stability of sunflower oil during thermal applications.
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The condensed mutation in sunflower
International Nuclear Information System (INIS)
Leclercq, P.
1978-01-01
Three inbred lines of sunflower were treated with gamma rays. In the progeny of one of these lines, the desired dwarf mutation appeared with a high frequency (23%). The dwarfing was accompanied by various undesirable characteristics (lateness, poor seed production, etc.), for which correction through genetic diversification and selection is in progress. The ratio capitulum diameter/stem height has increased from 1/8 up to 1/3 [fr
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Tocopherols and phytosterols in sunflower seeds for the human food market
Directory of Open Access Journals (Sweden)
Fernández-Cuesta, A.
2012-09-01
Full Text Available Sunflower seeds for the human food market are derived from both oilseed-type cultivars, with black achenes and low hull proportion, and confectionery-type cultivars, with striped achenes and high hull proportion. The objective of this research was to evaluate tocopherol and phytosterol contents in the seeds of both types of cultivars. Five oilseed-type and seven confectionery-type cultivars were evaluated in replicated field trials in two locations of Morocco and Spain. Large variations were found in hundred-kernel weight (2.6 to 5.5 g, kernel oil content (42.7 to 67.5%, tocopherol content (203 to 397 mg kg–1 kernel, and phytosterol content (2179 to 3555 mg kg–1 kernel. Both types of cultivars did not differ for kernel weight, kernel oil content, or tocopherol and phytosterol profiles. However, oilseed-type cultivars had significantly greater average tocopherol and phytosterol contents, though confectionery-type cultivars with levels of tocopherols and phytosterols similar to the best oilseed-type cultivars were identified. The large variations in kernel tocopherol and phytosterol contents found in this research suggest that there is room for breeding for increased levels of these compounds in order to develop healthier sunflower cultivars for the human food market.
Las semillas de girasol para consumo directo proceden tanto de cultivares oleaginosos, con aquenios negros y baja proporción de cáscara, como de cultivares de consumo directo, con aquenios de colores claros o rayados y elevada proporción de cáscara. El objetivo de este trabajo fue evaluar el contenido en tocoferoles y fitoesteroles en semillas de ambos tipos de cultivares. Se evaluaron cinco cultivares oleaginosos y siete cultivares de consumo directo en ensayos de campo replicados en dos localidades de Marruecos y España. Se identificó gran variación para peso de 100 semillas (aquenios descascarillados; 2.6 a 5.5 g, contenido en aceite en la -
International Nuclear Information System (INIS)
Jambhulkar, S.J.; Shitre, A.S.
2009-01-01
Mutation breeding programme in Indian mustard and sunflower at BARC has resulted into the development of wide spectrum of mutations for seed coat colour, chlorophyll, plant height, maturity, flower morphology, seed weight and oil content. In Indian mustard, TM1 and TM50 are high yielding yellow seed coat mutants, which were exploited in hybridisation to develop bold, yellow seed coat and high yielding genotypes. Light green leaf and variegated leaf are novel mutation in mustard. Putative mutants for drought tolerance have been isolated. Variability for zero erucic acid and zero glucosinolates genotypes have been developed in B. napus and B. juncea. In sunflower, high yielding black seed coat mutant were isolated. Extreme dwarf measuring only 11 cm is novel. Three high yielding varieties namely TM2, TM4, and TPM1 in mustard and one i.e.TAS82 in sunflower have been released for cultivation in collaboration with state agricultural universities. (author)
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Thakur, Anita; Bhatla, Satish C
2015-01-01
A noteworthy metabolic signature accompanying oil body (OB) biogenesis during oilseed development is associated with the modulation of the oil body membranes proteins. Present work focuses on 2-dimensional polyacrylamide gel electrophoresis (2-D PAGE)-based analysis of the temporal changes in the OB membrane proteins analyzed by LC-MS/MS accompanying the onset of desiccation (20–30 d after anthesis; DAA) in the developing seeds of sunflower (Helianthus annuus L.). Protein spots unique to 20–30 DAA stages were picked up from 2-D gels for identification and the identified proteins were categorized into 7 functional classes. These include proteins involved in energy metabolism, reactive oxygen scavenging, proteolysis and protein turnover, signaling, oleosin and oil body biogenesis-associated proteins, desiccation and cytoskeleton. At 30 DAA stage, exclusive expressions of enzymes belonging to energy metabolism, desiccation and cytoskeleton were evident which indicated an increase in the metabolic and enzymatic activity in the cells at this stage of seed development (seed filling). Increased expression of cruciferina-like protein and dehydrin at 30 DAA stage marks the onset of desiccation. The data has been analyzed and discussed to highlight desiccation stage-associated metabolic events during oilseed development. PMID:26786011
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Energy Technology Data Exchange (ETDEWEB)
Anwar, F.; Abdul Qayyum, H. M.; Hussein, A. I.; Iqbal, S.
2010-07-01
The antioxidant potential of 100% and 80% methanol extracts from the seeds of three barley varieties (Jou 83, Jou 87 and Haider 93) was assessed. The extract yields from barley seeds ranged from 3.23% (Haider 93,100% methanol) to 5.31% (Jou 83, 80% methanol). The total phenolic contents, DPPH radical scavenging activity (IC50 values) and inhibition of linoleic acid oxidation of barley seed extracts (BSE) were determined to be 88.1-145.7 mg/100g, 90.8-168.6 {mu}g/mL and 62.6-74.6%, respectively. The antioxidant effectiveness of BSE was also assessed by stabilizing sunflower oil (SFO) with BSE at a concentration of 600 ppm (oil weight basis). The stabilized (treated with extract) and the control (without extract addition) SFO samples were subjected to accelerated (oven heating at 60 degree centigrade for 30 days, 8 h heating cycle/day) storage. These were analyzed at regular intervals for the extent of oxidative changes according to the measurements of their contents of peroxide value, para-anisidine value, conjugated dienes and conjugated trienes. Generally, the 80% methanol extract of barely seeds demonstrated better antioxidant action than the 100% methanol extract. The antioxidant activity of BSE was also found to be considerably varied among the varieties tested. The present results suggest that antioxidant extracts from barely seeds might be used to protect vegetable oils from oxidation. (Author) 32 refs.
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Javanmard, T.; Zamani, Z.; Keshavarz Afshar, R.; Hashemi, M.; Struik, P.C.
2014-01-01
Seed germination in sweet cherry (Prunus avium L.) is a slow and lengthy process which has delayed breeding efforts. In this study, seed from ripe fruit of the sweet cherry cultivar ‘Lambert’ were collected and, after removing the endocarp, various dormancy-breaking treatments such as seed washing,
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Troncoso-Ponce, M A; Rivoal, J; Venegas-Calerón, M; Dorion, S; Sánchez, R; Cejudo, F J; Garcés, R; Martínez-Force, E
2012-07-01
Three cDNAs encoding different phosphoglycerate kinase (PGK, EC 2.7.2.3) isoforms, two cytosolic (HacPGK1 and HacPGK2) and one plastidic (HapPGK), were cloned and characterized from developing sunflower (Helianthus annuus L.) seeds. The expression profiles of these genes showed differences in heterotrophic tissues, such as developing seeds and roots, where HacPGK1 was predominant, while HapPGK was highly expressed in photosynthetic tissues. The cDNAs were expressed in Escherichia coli, and the corresponding proteins purified to electrophoretic homogeneity, using immobilized metal ion affinity chromatography, and biochemically characterized. Despite the high level of identity between sequences, the HacPGK1 isoform showed strong differences in terms of specific activity, temperature stability and pH sensitivity in comparison to HacPGK2 and HapPGK. A polyclonal immune serum was raised against the purified HacPGK1 isoform, which showed cross-immunoreactivity with the other PGK isoforms. This serum allowed the localization of high expression levels of PGK isozymes in embryo tissues. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
Maria Roseli Nicoli Spera
2001-12-01
Full Text Available Os objetivos deste trabalho foram avaliar a viabilidade de embriões de buriti (Mauritia flexuosa L. pelo teste de tetrazólio e cultivo in vitro, o tratamento térmico na quebra de dormência das sementes, e o efeito do armazenamento em duas temperaturas na conservação das sementes. A viabilidade de embriões de sementes recém-colhidas foi condizente com os resultados de germinação de embriões in vitro, com valores superiores a 90%. O estudo da quebra de dormência foi feito com tratamento das sementes em temperaturas de 30, 35 e 40ºC por períodos de 15, 30 e 45 dias. Até 15 e 30 dias, os resultados obtidos foram maiores que os do controle. Sementes armazenadas em saco de plástico por um período de quatro meses e meio, sob temperatura de 20ºC, apresentaram resultados de germinação de embrião superiores a 90%, e sob temperatura de 30ºC houve perda total da viabilidade.The present work was conducted to evaluate the viability of embryos of Mauritia flexuosa L. by tetrazolium test and in vitro culture, high temperature treatment on dormancy breaking, and the effect of storage at different temperatures on seed conservation. The viability of newly harvested embryos presented a high correlation with the rate of embryo germination in vitro. The rate of viability was higher than 90% either when evaluated by the tetrazolium method or by in vitro embryo culture. Dormancy breaking of seeds was tested by treating the seeds under temperatures of 30, 35 and 40ºC for 15, 30, and 45 days. Great variation was observed among treatments, but, at least on day 15 and on day 30, the germination was higher than in the control. Seeds stored in plastic bags for four and a half months and temperature of 20ºC presented a germination rate higher than 90% while in the seeds stored at 30ºC the viability was zero.
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Directory of Open Access Journals (Sweden)
Xi Ling Fu
Full Text Available Dormancy mechanisms in seeds and buds arrest growth until environmental conditions are optimal for development. A genotype-specific period of chilling is usually required to release dormancy, but the underlying molecular mechanisms are still not fully understood. To discover transcriptional pathways associated with dormancy release common to seed stratification and bud endodormancy, we explored the chilling-dependent expression of 11 genes involved in endoplasmic reticulum stress and the unfolded protein response signal pathways. We propose that endoplasmic reticulum stress and the unfolded protein response impact on seed as well as bud germination and development by chilling-dependent mechanisms. The emerging discovery of similarities between seed stratification and bud endodormancy status indicate that these two processes are probably regulated by common endoplasmic reticulum stress and unfolded protein response signalling pathways. Clarification of regulatory pathways common to both seed and bud dormancy may enhance understanding of the mechanisms underlying dormancy and breeding programs may benefit from earlier prediction of chilling requirements for uniform blooming of novel genotypes of deciduous fruit tree species.
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Development of sunflower germplasm with high delta-tocopherol content
Velasco L.; Pérez-Vich B.; Fernández-Martínez J.M.
2004-01-01
Tocopherols are the main compounds with antioxidant activity in oilseeds Sunflower seeds contain predominantly alpha-tocopherol, which accounts for more than 90% of the total tocopherols in the seeds. This tocopherol derivative possesses a maximum vitamin E or in vivo antioxidant activity, but it exerts a minimum in vitro protective action in oils and food containing them. Other tocopherol derivatives such as beta-, gamma-, and delta-tocopherol are more powerful antioxidants than alpha-tocoph...
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Strategies for Seed Propagation of Native Forbs
Susan E. Meyer
2006-01-01
Native forbs are an increasingly important component of container production for many public and private nurseries. Propagators are often called upon to grow species with unknown requirements. A systematic approach is required to obtain plants from seeds of these species, beginning with determining what is a propagule and evaluating seed quality. Next, seed dormancy...
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Dormancy overcome and seedling quality of pecan in nursery
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Tales Poletto
Full Text Available ABSTRACT: This study evaluated the efficiency of methods to overcome seed dormancy in different storage periods in the production of pecan seedlings. Seeds were submitted to the following treatments: T1, T4 and T7 - control treatments (seeds with no treatment, stored at room temperature for 30, 60 and 90 days, respectively, T2, T5 and T8 - stratification (seeds were distributed in boxes with wet sand maintained at a temperature of 4°C for 30, 60 and 90 days, respectively, T3, T6 and T9 - scarification + stratification (seeds scarified with sandpaper n.80 and stratified by 30, 60 and 90 days, respectively, in completely random experimental design. Plant height, stem diameter, number of leaves, full emergence and emergence speed index (ESI were evaluated after 14 weeks of sowing. The best development of pecan 'plants, their emergence, and ESI were observed in the stratification treatment for 90 day as well as in the scarification + stratification treatment for 90 day. Storing seeds in uncontrolled environment reduced their viability.
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Basal stalk rot (BSR) caused by Sclerotinia sclerotiorum (Lib.) de Bary is a devastating disease that causes a significant damage to worldwide sunflower (Helianthus annuus L.) production by reducing seed yield and quality. The objective of this research was to develop highly BSR tolerant sunflower g...
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Phytoremediation of Lead and Cadmium Contaminated Soils using Sunflower Plant
Directory of Open Access Journals (Sweden)
Nasser Sewalem
2014-03-01
Full Text Available Phytremediation has emerged as a practical approach to clean up metal-polluted soils. In this study the role of sunflower (Helianthus annuus L. plants as a potential phytoremediator to soils contaminated with cadmium (Cd and lead (Pb was investigated. Our results showed that the effect of Cd was stronger on the growth of the roots, while the effect of Pb was stronger on the shoots of sunflower seedlings. At the physiological level, Cd treatment was found to induce low levels of lipid peroxidation and membrane leakage with less affected photosynthesis in the leaves of the treated sunflower seedlings compared to the effects of Pb. The results presented here showed that a high amount of the total absorbed Cd (88.84% was accumulated in roots, while a high amount of the total absorbed Pb (71.39 was tranlocated to shoots of sunflower seedlings. Similar trends of Cd and Pb allocation between roots and shoots at the yield stage were recorded. We suggest here that sunflower plants may remediate Cd contaminated soils through phytostabilization, while may remediate Pb contaminated soils through phytoextraction. Finaly, the trace amounts of Cd and Pb that were accumulated in seeds recommends sunflower plants to be used safely and economically for cleaning up soils contaminated with Cd and/or Pb.
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Analysis and modelling of the factors controlling seed oil concentration in sunflower: a review
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Andrianasolo Fety Nambinina
2016-03-01
Full Text Available Sunflower appears as a potentially highly competitive crop, thanks to the diversification of its market and the richness of its oil. However, seed oil concentration (OC – a commercial criterion for crushing industry – is subjected to genotypic and environmental effects that make it sometimes hardly predictable. It is assumed that more understanding of oil physiology combined with the use of crop models should permit to improve prediction and management of grain quality for various end-users. Main effects of temperature, water, nitrogen, plant density and fungal diseases were reviewed in this paper. Current generic and specific crop models which simulate oil concentration were found to be empirical and to lack of proper evaluation processes. Recently two modeling approaches integrating ecophysiological knowledge were developed by Andrianasolo (2014, Statistical and dynamic modelling of sunflower (Helianthus annuus L. grain composition as a function of agronomic and environmental factors, Ph.D. Thesis, INP Toulouse: (i a statistical approach relating OC to a range of explanatory variables (potential OC, temperature, water and nitrogen stress indices, intercepted radiation, plant density which resulted in prediction quality from 1.9 to 2.5 oil points depending on the nature of the models; (ii a dynamic approach, based on “source-sink” relationships involving leaves, stems, receptacles (as sources and hulls, proteins and oil (as sinks and using priority rules for carbon and nitrogen allocation. The latter model reproduced dynamic patterns of all source and sink components faithfully, but tended to overestimate OC. A better description of photosynthesis and nitrogen uptake, as well as genotypic parameters is expected to improve its performance.
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Productivity analysis of sunflower production in Turkey
International Nuclear Information System (INIS)
Semerci, A.
2012-01-01
In Turkey, which ranks the tenth country worldwide in the sunflower (Helianthus annuus L.) production, 55% of the production is carried out in Thrace Region. Therefore, agricultural enterprises in Thrace Region, situated in the European part of Turkey have specialized in producing sunflower, and have become the centre of vegetable oil industry in the region in terms of produced raw material. This research was conducted in 182 agricultural enterprises in 3 provinces of Thrace Region in Turkey and its objective was to determine input/output relations in sunflower production. The study indicates that the determination coefficient (r/sup 2/) derived from Cobb-Douglas production function was significant at 0.01 level and the elasticity coefficients of the variables (except chemical fertilizer) were found beta i positive in derived equation. It was determined that the variable of herbicide cost had the highest value of the marginal effectiveness coefficients and none of the variables was used at economically optimal level in the study area. When the Marginal Technical Substitution and the Price Rates were taken into consideration, it was noted that only the seed cost/hoeing cost was closest to economically optimum level (1.10). According to stepwise analysis the Land Renting Value was determined as the most important variable in sunflower production. (author)
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Directory of Open Access Journals (Sweden)
Marco Antônio Curado
2007-09-01
dormancy and reduce time for seedling production na experiment was carried out with seeds collected at the Alternative Medical Hospital in Goiânia, Brazil, at October 2000 and subject to the following treatments: a peeled seeds, b peelled seeds washed in running water for five minutes, c peelled seeds washed in running water for five minutes and soaked in a 50% detergent solution and then washed in running water for two minutes, d peelled seeds washed in running water for five minutes, then soaked in hypochloeite solution then washed for two minutes, e control. Four replications were used in a completely randomized design. After 21 days it was observed no germination in the control treatment. Pelling increased germination to 56%. The peeled and water washed seed treatments, and those with washed and then hypochlorite soaked seeds caused germination rate increase, but did not differ significantly from those which just the seed peel was removed (58 and 56% germination rate, respectively. The higher germination rate (73% was observed with peeled and washed seeds that were soaked in detergent solution, however no significant differences were found as compared to the water washed and hypochlorite soaked seed treatments.
KEY-WORDS: Seeds; dormancy; black pepper.
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Directory of Open Access Journals (Sweden)
Stanković Vesna
2003-01-01
Full Text Available In the Agricultural & Technological Research Centar in Zajecar the work on improvement of sunflower were initiated in 1980s. Besides improvement, in relation to the main components of yield and high genetic potential for yield in improvement programmes of consuming genotypes of sunflower, there are some specific aims, such as: increasing the of 1000 seeds, reducing the portion of a shell, uniformity of the seed color and size. The latest achievements of the sunflower improvement carried out in the Centre in Zajecar are: obtaining the consuming-type hybrid PROTEINAC 94 (released in 1998, the hybrid JUNIOR (released in 2001, and the synthetic protein cultivar ZENIT (released in 2003. At the start of the 1990s, it was initiated the work on researching the agronomic characteristics of the existing assortment of oil-flax, as well as on preparation for plant improvement is to obtain high-yielding cultivars of brown and yellow seed color that can be used both for oil extraction and for consummation. During the research, a certain number of lines of oil-flax with positive characteristics were created. In 2003 the flax cultivar with the yellow color of seed, ZLATKO, was released. .
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Effects of gamma radiation in annatto seeds
Energy Technology Data Exchange (ETDEWEB)
Franco, Camilo F. de Oliveira, E-mail: camilo.urucum@hotmail.com [Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA/EMEPA), Joao Pessoa, PB (Brazil); Arthur, Valter; Arthur, Paula B., E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Harder, Marcia N.C., E-mail: marcia.harder@fatec.sp.gov.br [Centro Paula Souza, Curso Superior de Tecnologia em Bicombustiveis (FATEC), Piracicaba, SP (Brazil); Filho, Jose C.; Neto, Miguel B., E-mail: jorgecazefilho@yahoo.com.br [Empresa Estadual de Pesquisa Agropecuaria da Paraiba (EMEPA), Joao Pessoa, PB (Brazil)
2015-07-01
The annatto bixin has emerged as a major source of natural dyes used in the world notably by the substitution of synthetics harmful to human health and ecologic tendency in obtaining industrial products free of additives with applications in industries textiles; cosmetics; pharmaceutical and food mainly. The aim of this research was to obtain increased of germination rate and dormancy breaking on annatto seeds by gamma radiation. Annatto dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.456 kGy/hour dose rate. In order to study stimulation effects of radiation on germination rate and dormancy breaking in the seeds. Five treatments with gamma radiation doses were applied as follows: 0 (control); 100; 125; 150 and 175 Gy. After irradiation the annatto seeds were planted as for usual seed production. According to the results obtained in this experiment we can conclude that the low doses of gamma radiation utilized on the annatto seeds did not presented significantly effect on the germination of plants. But the best dose to increase the germination of seeds was 150 Gy. (author)
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Effects of gamma radiation in annatto seeds
International Nuclear Information System (INIS)
Franco, Camilo F. de Oliveira; Arthur, Valter; Arthur, Paula B.; Harder, Marcia N.C.; Filho, Jose C.; Neto, Miguel B.
2015-01-01
The annatto bixin has emerged as a major source of natural dyes used in the world notably by the substitution of synthetics harmful to human health and ecologic tendency in obtaining industrial products free of additives with applications in industries textiles; cosmetics; pharmaceutical and food mainly. The aim of this research was to obtain increased of germination rate and dormancy breaking on annatto seeds by gamma radiation. Annatto dry seeds were exposed to low doses of gamma radiation from source of Cobalt-60, type Gammecell-220, at 0.456 kGy/hour dose rate. In order to study stimulation effects of radiation on germination rate and dormancy breaking in the seeds. Five treatments with gamma radiation doses were applied as follows: 0 (control); 100; 125; 150 and 175 Gy. After irradiation the annatto seeds were planted as for usual seed production. According to the results obtained in this experiment we can conclude that the low doses of gamma radiation utilized on the annatto seeds did not presented significantly effect on the germination of plants. But the best dose to increase the germination of seeds was 150 Gy. (author)
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Directory of Open Access Journals (Sweden)
Valquíria Nogueira Camargos
2008-12-01
Full Text Available A avaliação da qualidade fisiológica de lotes de sementes de Sesbania virgata é dificultada pela dormência inerente à espécie, bem como pela inadequação metodológica de testes disponíveis. Para desenvolver procedimentos adequados à avaliação da qualidade das sementes de S. virgata, foram avaliados métodos tanto para quebra de dormência como para realização do teste de tetrazólio. Em uma primeira fase, as sementes de cinco lotes foram submetidas a tratamentos para quebra de dormência: lixa, ácido e corte do tegumento, previamente ao teste de germinação. Para caracterização dos lotes e adequação da metodologia do teste de tetrazólio, na segunda fase, as sementes foram lixadas na região oposta ao eixo embrionário, e submetidas aos seguintes testes: tetrazólio, germinação, velocidade de emergência, peso de matéria fresca e de matéria seca de plântulas. Foram utilizados dois métodos de pré-condicionamento: embebição em papel por 18 h a 30 ºC e imersão em água por 12 h a 30 ºC e três períodos (uma, duas e três horas de imersão em solução de tetrazólio 0,5%. Na análise do perfil dos lotes de S. virgata foram detectadas variações na qualidade fisiológica pelos resultados dos testes de vigor e germinação. O método de escarificação com lixa possibilitou a quebra de dormência das sementes de S. virgata,e o pré-condicionamento das sementes em papel com embebição em solução de tetrazólio 0,5% por duas horas é um procedimento adequado para avaliação da viabilidade das sementes.The evaluation of Sesbania virgata seed physiological quality is hampered by its intrinsic seed dormancy and inadequate methodologies among available tests. To develop an adequate procedure to evaluate S. virgata seed quality, methods for dormancy breaking and tetrazolium test accomplishment were evaluated. In a first stage, seeds from five lots were submitted to dormancy breaking methods: sandpaper, acid and
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de Waal, Caroli; Anderson, Bruce; Ellis, Allan G
2016-04-01
Dispersal and dormancy are important risk-reducing strategies in unpredictable environments. Negative covariation between these strategies is theoretically expected, but empirical evidence is limited and inconsistent. Moreover, covariation may be affected by other life-history traits and may vary across levels of biological organization. We assessed dispersal (vertical fall time of fruits, a proxy for wind dispersal ability) and dormancy (germination fractions measured during germination trials) in populations of 15 annual and 12 perennial wind-dispersed species in six Asteraceae genera from South Africa. Dormancy was higher in annuals than in perennials, whereas fall time was largely determined by evolutionary history. Controlling for phylogeny, dispersal and dormancy was negatively associated across species and life-history categories. Negative covariation between dispersal and dormancy was not evident at either the individual level (except for seed heteromorphic species) or the population level. Our study provides rare empirical support for the theoretical expectation of tradeoffs between dormancy and the alternative risk-reducing strategies, perenniality and dispersal, but refutes the expectation of increased dispersability in perennials. Although negative covariation between dispersal and dormancy at the species level appears not to be a simple consequence of upscaling individual-level mechanistic tradeoffs, our findings suggest that selection for one strategy may constrain evolution of the other. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
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Seed ecology of Bromus sterilis L.
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Žďárková, Veronika
2014-02-01
Full Text Available Bromus sterilis L. (barren brome has become a troublesome weed of winter cereals in reduced tillage systems, mainly in South and North America, middle and Western Europe. In the Czech Republic, its importance has increased dramatically over the past 10 years. Barren brome is reported as a problem weed in other winter crops such as oil seed rape, in vineyards and in other cultivated places. In this study, the dormancy and germination under different temperatures, water and light regimes were investigated. Emergence from different depths and persistence in the soil profile were investigated under field conditions. The seeds of Bromus sterilis showed broad ecological valence to hydrothermal factors germinating in the wide range of 5 to 35 °C. Similarly, no strong effect on the germination in an environment with low water potential was observed. The response to light at various temperatures showed that seeds germinated better in darkness. The emergence declined significantly with burial depth (under 40 mm. The loss of primary dormancy was rapid in time and only 50% of the seeds germinated within 8 weeks after collecting from maternal plants. The seeds were not able to survive in the soil seed bank for a longer time and fall seeds lost viability 1 year after burial in a soil profile.
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Sunflower proteins : overview of their physicochemical, structural and functional properties
González-Pérez, S.; Vereijken, J.M.
2007-01-01
There is increasing worldwide demand for proteins of both animal and plant origin. However, animal proteins are expensive in terms of both market price and environmental impact. Among alternative plant proteins, sunflower seeds are particularly interesting in view of their widespread availability in
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Whole plant senescence of sunflower following seedhead removal
International Nuclear Information System (INIS)
Ho, InSun; Below, F.E.
1989-01-01
This study was undertaken to further clarify the relationship between seed development and monocarpic senescence of sunflower (Helianthus annuus L.). Field-grown plants with and without seedheads were evaluated for rate and duration of accumulation of dry weight, reduced N, and P by whole shoots, and for partitioning of these constituents within the individual plant parts. Concurrent with seedhead removal, [ 15 N]nitrate was applied to the plants in a selected are of the experimental plot. Whole plants (above ground portions) were harvested seven times during the seed-filling period and analyzed from dry weight, reduced N, and P. Although seedhead removal depressed the rates of dry weight, reduced N, and P accumulation by whole shoots, it extended the duration of accumulation of these constituents, relative to headed control plants. As a result, the final whole shoot dry weight and N and P contents at seed maturity were similar for deheaded and headed plants. Seedhead removal also affected the partitioning of dry matter, reduced N, and P but the relative proportions varied as a function of constituent and growth stage. Analysis of 15 N present in whole shoots at physiological maturity showed that similar amounts of nitrate were absorbed during the postflowering period by headed and deheaded plants. These data indicate that the absence of seeds does not affect the total accumulation of dry matter, reduced N, or P, by sunflower plants, but does alter the rates of accumulation and partitioning of these constituents
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Proceedings of the second Australian workshop on native seed biology for revegetation
Energy Technology Data Exchange (ETDEWEB)
Bellairs, S.M.; Osborne, J.M. [eds.
1997-06-01
This conference on the use of native seed for revegetation in Australia focused on four areas; seed provenance areas; soil seed banks; seed dormancy and germinability; and seed testing; Four papers on revegetation of coal mining areas have been abstracted separately on the IEA Coal Research CD-ROM.
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Directory of Open Access Journals (Sweden)
Nolasco, S.M.
2007-06-01
Full Text Available The effect of night temperature during short periods in seed filling on oil tocopherol content and tocopherol/linoleic acid ratio was investigated in a traditional sunflower hybrid. Seeds were sown in the field at Balcarce on the 3rd and 22nd of November. In each experiment, treatments in which night temperature was increased at three consecutive periods of 200 °C day (base temperature: 6 °C were applied.Tocopherol concentration was reduced when night temperature was increased early in seed filling. Such an increase could be attributed to a correlative increase in the daily average temperature, as no differences in tocopherol concentration were found when plants were cultivated in growth chambers under different day/night temperature but at the same daily average temperature. Temperature affected tocopherol concentration mainly by affecting the oil weight per seed.The tocopherol/linoleic acid ratio was not affected by temperature.Se investigó el efecto de la temperatura durante períodos cortos en el llenado de las semillas sobre la concentración de tocoferoles y la relación tocoferoles/ácido linoleico en un híbrido tradicional de girasol. Se realizó una siembra en campo en Balcarce el 3 y el 22 de noviembre. En cada experimento, se aplicaron tratamientos donde se incrementó la temperatura de la noche en tres períodos consecutivos de 200 °C día (temperatura base: 6 °C. La concentración de tocoferoles disminuyó cuando se incrementó la temperatura de la noche temprano durante el llenado de las semillas. Dicho aumento puede ser atribuido a aumentos en la temperatura media diaria ya que no se observaron diferencias en la concentración de tocoferoles cuando se cultivaron plantas en cámaras de crecimiento con distinta temperatura nocturna y la misma temperatura media diaria. La temperatura afectó la concentración de tocoferoles principalmente al afectar el peso de aceite por semilla. La relación tocoferoles/
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Directory of Open Access Journals (Sweden)
Jennifer B Landesmann
Full Text Available Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb. We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.
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Landesmann, Jennifer B; Gundel, Pedro E; Martínez-Ghersa, M Alejandra; Ghersa, Claudio M
2013-01-01
Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb). We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.
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Directory of Open Access Journals (Sweden)
S. Gómez-González
2018-01-01
Full Text Available In fire-prone ecosystems, many plant species have specialized mechanisms of seed dormancy that ensure a successful recruitment after fire. A well-documented mechanism is the germination stimulated by fire-related cues, such as heat shock and smoke. However, less is known about the role of inhibitory germination signals (e.g. allelopathy in regulating post-fire recruitment. Plant leachates derived from the unburned vegetation can enforce dormancy by means of allelopathic compounds, acting as a signal of unfavourable (highly competitive niche for germination in pyrophyte species. Here, we assessed the separate effects of heat shock and plant leachates on seed germination of Drosophyllum lusitanicum, an endangered carnivorous plant endemic to Mediterranean fire-prone heathlands. We performed a germination experiment in which seeds were subjected to three treatments: (1 5 min at 100 °C, (2 watering with plant leachate, and (3 control. Germination rate and seed viability was determined after 63 days. Heat shock stimulated seed germination in D. lusitanicum while plant leachates had inhibitory germination effects without reducing seed viability. Thus, both positive and negative signals could be involved in its successful post-fire recruitment. Fire would break seed dormancy and stimulate seed germination of D. lusitanicum through high temperatures, but also by eliminating allelochemical compounds from the soil. These results help to understand the population dynamics patterns found for D. lusitanicum in natural populations, and highlight the role of fire in the ecology and conservation of this endangered species. Seed dormancy imposed by plant-derived leachates as an adaptive mechanism should be considered more in fire ecology theory.
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Some results of applied interspecific hybridization in sunflower breeding
International Nuclear Information System (INIS)
Tsvetkova, F.
1976-01-01
Investigations on the interspecific hybridization in sunflower, aimed at developing a diversified initial selection material, were carried out Wild species of the diploid, tetraploid and hexaploid groups, varieties, hybrids, and selfed-lines of cultivated sunflower were used for crossings. To overcome incrossability between the species and sterility in the hybrids the method of f;cilitating of crossability by mutual gra'fting and gamma-rays treatment of seeds and pollen were applied. Results showed that: 1. By the method of interspecific hybridization forms might be produced resistant to more important diseases. 2. Interspecific hybridization in combination with other methods of selection might produce varieties and hybrids with a complex of valuable qualities. 3. Crossings between wild species and cultivated sunflower gave progenies with gene rale sterility. 4. The species H.tuberosus, H.scaberimus, H.arωphylus and H.lenticularis possess genes of full fertility restoration. (author)
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Valorization of sunflower meal through the production of ethanol from the hemicellulosic fraction
Directory of Open Access Journals (Sweden)
Bruna Tavares
Full Text Available ABSTRACT Sunflower is among the major oil seeds crop grown in the world and the by-products generated during the seeds processing represent an attractive source of lignocellulosic biomass for bioprocesses. The conversion of lignocellulosic fibers into fermentable sugars has been considered as a promising alternative to increase the demand for ethanol. The present study aimed to establish the fermentation conditions for ethanol production by Scheffersomyces stipitis ATCC 58376 in sunflower meal hemicellulosic hydrolysate, through a 23 CCRD (Central Composite Rotational Design factorial design. Under the selected conditions (pH 5.25, 29 ºC and 198 rpm the final ethanol concentration was 13.92 g L-1 and the ethanol yield was 0.49 g g-1.
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Viability of Macrotyloma axillare cv. Guatá seeds under chemical scarification
Directory of Open Access Journals (Sweden)
Suleize Rocha Terra
2012-12-01
Full Text Available The use of the associacion of grasses and legumes results in a good forage yield as well as a good animal performance due to maintenance of adequate levels of crude protein (CP in the animal diet, both the direct effect of the ingestion of legumes, or even through indirect effect of the introduction of nitrogen by legumes in the pasture, thereby increasing the production of forage mass. However, the seeds of legumines have the so-called hardness seeds or dormant according to their coats impermeable to water. The hardness of the seed prevents the germination of the same since these seeds have a hard shell impervious to water and gas exchange, not allowing the imbibition of water by the seed, or embryo oxygenation. This dormancy may be broken by various known methods such as scarification, promoting cracks in the seed coat allowing the entry of water therein. In the case of Macrotyloma axillare exposure of seeds to scarification method has proven to be an efficient way to break dormancy and promoting seed germination. The aim of the present work was to evaluate the viability of seeds after suffering dormancy by immersion seeds in sulfuric acid. The experiment to break dormancy Macrotyloma axillares cv. Guatá was conducted in the laboratory of Plant Physiology at the Intituto de Zootecnia in Nova Odessa, São Paulo State, using the seeds that were stored in a cold room with temperatures between 10-12 ºC, relative humidity (RH 30-33% and no light. The treatments studied were: control, chemical scarification with sulfuric acid for 5, 10, 15, 20, 30 and 40 minutes. We used a completely randomized design with two replications, being 100 seeds each repetition. After treatment the seeds were under to tetrazolium test resulting in viable seeds and seed viability. So the result of the tetrazolium test was obtained by average percentage of viable seeds, found in the repeats tested, respecting the maximum tolerances set out in Brazilian Rules for Seed
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Germination of red alder (Alnus rubra) seed from several locations in its natural range
Energy Technology Data Exchange (ETDEWEB)
Elliott, D.M.; Taylor, I.E.P.
1981-01-01
Tests were carried out on stratified, pre-soaked or untreated seeds. Germination of all provenances and treatments was more than 90%, except for one provenance showing physiological dormancy in which germination was low, but increased significantly with stratification and presoaking; dormancy could be broken completely by chilling at 0 degrees C for 5 days. Significant interactions were found between provenances and treatments for both germination % and seed vigour (as measured by germination value).
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Research on resistance to sunflower broomrape: an integrated vision
Directory of Open Access Journals (Sweden)
Velasco Leonardo
2016-03-01
Full Text Available Sunflower broomrape (Orobanche cumana Wallr. parasitization on sunflower was first observed at the end of the 19th century and has continued since then jeopardizing sunflower cultivation in many areas of Europe and Asia. A distinctive characteristic of the O. cumana-sunflower parasitic system is that it is mainly governed by a gene-for-gene interaction. This determines complete resistance in the host controlled by dominant alleles at a single locus, which facilitates the management of the resistance for hybrid seed production. But on the other hand avirulence in the parasite is also controlled by dominant alleles at a single gene. Monogenic, dominant resistance exerts a strong selection pressure on the parasite that maximizes the probability of overcoming resistance mechanisms in a short period of time. This has in fact resulted in a number of physiological races that periodically surpass all the available resistance sources. The spread of populations to new areas and the subsequent hybridization between populations is another mechanism creating genetic diversity in sunflower broomrape and allegedly recombination of avirulences genes. After more than one century of coexistence, genetic resistance to broomrape in sunflower has to be focused under an integrated approach that considers not only the characterization of resistance mechanisms in the host, but also the genetic and physiological bases of avirulence in the parasite. From the perspective of genetic resistance in sunflower, most important is not relying only on single dominant genes, but following instead pyramiding strategies. These should give priority to combining complementary mechanisms of resistance under both qualitative (vertical and quantitative (horizontal genetic control. These aspects are discussed in the paper.
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Seed ecology and regeneration in dry Afromontane forests of Ethiopia
Energy Technology Data Exchange (ETDEWEB)
Teketay, D. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Vegetation Ecology
1996-12-31
Various aspects of seed and regeneration ecology: germination requirements of seeds, seed longevity in the soil, soil seed banks in forests, gaps and arable land as well as density, survival and growth of seedlings were investigated within the dry Afromontane region in Ethiopia. In laboratory germination tests, 60% of the species studied exhibited some degree of initial dormancy and the optimum constant temperature for germination was between 20 and 25 deg C in the majority of the species. A few species showed a requirement for fluctuating temperatures and germination was suppressed or completely inhibited in several, mainly small-seeded, species when they were incubated in darkness or in light filtered through green leaves. Hard-seeded species required scarification treatments to improve germination, indicating seed-coat imposed dormancy. Dry storage reduced the germinability of seeds in a few species, suggesting a recalcitrant behaviour, while seeds of many species remained unaffected. During four years of storage in forest soils, seeds of 2 out of 8 species germinated in the soil almost completely within a year, 2 of the species maintained nearly full viability, while 4 were intermediate. The generally high levels of dormancy and somewhat extended viability of seeds in the soil may have been selected for under a climate of seasonal drought and unreliable rainfall that characterizes the dry Afromontane region. Dry Afromontane forests have a potential to recover in relatively short time after natural and man-made disturbances, e.g. after carefully managed selective cutting. However, the common practice of clearing forests and converting them into permanent arable land destroys the sources of regrowth thereby preventing regeneration of the forest vegetation. Therefore, the fate of dry Afromontane forests depends on the protection, careful management and conservation of the remaining patches. 102 refs, 4 figs, 1 tab
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Directory of Open Access Journals (Sweden)
k Hajmohammadnia Ghalibaf
2011-02-01
Full Text Available Abstract In order to study the effects of four chickpea cultivar (Cicer arietinum L. on vegetative growth of sunflower (Helianthus annus and corn (Zea mays, two separate experiments was conducted at Research Greenhouse of Ferdowsi University of Mashhad in 2005. Experiments were done in a factorial arrangement of treatments with two factors based on completely randomized design with 4 replications. Factors included chickpea cultivars (Karag12-60-31, Filip 84-482, Gam, ILC 482, and no residue control and planting date of corn and sunflowers within root residues of chick pea (seeds planted simultaneously, 2 weeks, and 4 weeks after harvesting of chickpea shoots. Seeds of corn and sunflower were planted within root residues of chickpea. Results showed that root residues of chickpea cultivars influenced height and shoot weight of sunflower significantly. The lowest sunflower height was obtained when they were planted within root residues of Flip and ILC cultivars, which decreased 13.7 and 11.1% relative to control, respectively. Planting date of sunflower within root residues of chick pea cultivars had a significant effect on sunflower leaf area, shoot weight, and its root/shoot ratio. So that, lowest leaf area, shoot weight, and also highest root/shoot ratio was obtained in third planting date. Results showed that lowest plant height, leaf area, root weight, shoot weight, and also highest root/shoot ratio of corn (6 weeks after planting was obtained after planting within chickpea cultivars, Gam and ILC. Also the effect of corn planting date was significant. The lowest root and shoot weight, and root/shoot ratio of corn was obtained in the earliest corn planting date. Therefore, corn plants showed more sensitive than sunflower after planting within chickpea cultivars, and the highest inhibitory effects resulted in the earliest corn planting date. Keywords: Pea cultivars, Integrated management, Crop rotation
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Genetics of alternative splicing evolution during sunflower domestication.
Smith, Chris C R; Tittes, Silas; Mendieta, J Paul; Collier-Zans, Erin; Rowe, Heather C; Rieseberg, Loren H; Kane, Nolan C
2018-06-11
Alternative splicing enables organisms to produce the diversity of proteins necessary for multicellular life by using relatively few protein-coding genes. Although differences in splicing have been identified among divergent taxa, the shorter-term evolution of splicing is understudied. The origins of novel splice forms, and the contributions of alternative splicing to major evolutionary transitions, are largely unknown. This study used transcriptomes of wild and domesticated sunflowers to examine splice differentiation and regulation during domestication. We identified substantial splicing divergence between wild and domesticated sunflowers, mainly in the form of intron retention. Transcripts with divergent splicing were enriched for seed-development functions, suggesting that artificial selection impacted splicing patterns. Mapping of quantitative trait loci (QTLs) associated with 144 differential splicing cases revealed primarily trans -acting variation affecting splicing patterns. A large proportion of identified QTLs contain known spliceosome proteins and are associated with splicing variation in multiple genes. Examining a broader set of wild and domesticated sunflower genotypes revealed that most differential splicing patterns in domesticated sunflowers likely arose from standing variation in wild Helianthus annuus and gained frequency during the domestication process. However, several domesticate-associated splicing patterns appear to be introgressed from other Helianthus species. These results suggest that sunflower domestication involved selection on pleiotropic regulatory alleles. More generally, our findings indicate that substantial differences in isoform abundances arose rapidly during a recent evolutionary transition and appear to contribute to adaptation and population divergence.
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Primary dispersal of Cytisus multiflorus seeds
Directory of Open Access Journals (Sweden)
Moreno Marcos, G.
1992-12-01
Full Text Available Current work relates to the primary dispersal of Cytisus multiflorus seeds: seed production, dispersal mechanisms, distribution of seed after dissemination and dormancy were investigated. The distribution of seed was recorded before collection; seed viabilaty and dormancy were assessed. The results indicate that the dispersion is assisted by an explosive dehiscence of the seed pod in that only 35% of the seed drop directly beneath the plant, the remainder falling further away, some reaching distances greater than 3 m. Dormancy index was found to be 98.9%.
[es] En el presente trabajo se estudia la dispersión primaria de las semillas de Cytisus multiflorus: cuantificación de la producción, mecanismos de dispersión, distribución de las semillas tras la diseminación, y su estado de latencia. Para ello se colocaron dispositivos de recogida de las semillas debajo y alrededor de las plantas, anotando la cantidad y distancia de la calda; posteriormente eran sembradas para comprobarla viabilidad y dormición de las semillas. Los resultados indican la existencia de una dispersión por dehiscencia explosiva; solamente el 35% de las semillas caen bajo la planta, haciéndolo el resto en sus alrededores; algunas alcanzaron distancias superiores a los 3 m. El índice de dormición es de 98.9%.
[fr] Dans le présent travail on étudie la dispersion primaire des graines de Cytisus multiflorus: quantification de la production, mécanismes de dispersion, distribution des graines après la dissémination et leur état de latence. Pour ce faire on a placé des dispositifs de récolte des graines au dessous et autour des plantes, enregistrant la quantité et la distance de la chute; après elles étaient semées pour tester la viabilité et dormance des graines. Les résultats indiquent l'existence d'une dispersion par déhiscence explosive; seulement 35% des graines tombent au-dessous de la plante, et le reste dans les -
Seed anatomy, moisture content and scarification influence on ...
African Journals Online (AJOL)
Low and erratic germination in wild banana seed is caused by dormancy due to physical, anatomical or physiological reasons. Imbibition activates germination process and the rate of water uptake during imbibition is influenced by seed molecular composition and internal and external morphological structures. The present ...
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Energy Technology Data Exchange (ETDEWEB)
Wu, Jian; Seng, Shanshan [Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University, Beijing 100193 (China); Carianopol, Carina [Department of Biological Sciences, University of Toronto, Toronto, Ontario (Canada); Sui, Juanjuan [College of Biology, Fuyang Normal College, Fuyang, Anhui (China); Yang, Qiuyan; Zhang, Fengqin; Jiang, Huiru [Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University, Beijing 100193 (China); He, Junna, E-mail: hejunna@cau.edu.cn [Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University, Beijing 100193 (China); Yi, Mingfang, E-mail: ymfang@cau.edu.cn [Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University, Beijing 100193 (China)
2016-02-26
Abscisic acid (ABA) is an important phytohormone controlling seed dormancy. AFPs (ABA INSENSITIVE FIVE BINDING PROTEINS) are reported to be negative regulators of the ABA signaling pathway. The involvement of AFPs in dormant vegetative organs remains poorly understood. Here, we isolated and characterized a novel AFP family member from Gladiolus dormant cormels, GhAFP-like, containing three conserved domains of the AFP family. Quantitative PCR analysis revealed that GhAFP-like was expressed in dormant organs and its expression was down-regulated along with corm storage. GhAFP-like was verified to be a nuclear-localized protein. Overexpressing GhAFP-like in Arabidopsis thaliana not only showed weaker seed dormancy with insensitivity to ABA, but also changed the expression of some ABA related genes. In addition, a primary root elongation assay showed GhAFP-like may involve in auxin signaling response. The results in this study indicate that GhAFP-like acts as a negative regulator in ABA signaling and is related to dormancy. - Highlights: • GhAFP-like is expessed in dormant corm. • Overexpressing GhAFP-like showed early germination and insensitivity to ABA. • Overexpressing GhAFP-like changed ABI5 downstream genes expression.
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International Nuclear Information System (INIS)
Wu, Jian; Seng, Shanshan; Carianopol, Carina; Sui, Juanjuan; Yang, Qiuyan; Zhang, Fengqin; Jiang, Huiru; He, Junna; Yi, Mingfang
2016-01-01
Abscisic acid (ABA) is an important phytohormone controlling seed dormancy. AFPs (ABA INSENSITIVE FIVE BINDING PROTEINS) are reported to be negative regulators of the ABA signaling pathway. The involvement of AFPs in dormant vegetative organs remains poorly understood. Here, we isolated and characterized a novel AFP family member from Gladiolus dormant cormels, GhAFP-like, containing three conserved domains of the AFP family. Quantitative PCR analysis revealed that GhAFP-like was expressed in dormant organs and its expression was down-regulated along with corm storage. GhAFP-like was verified to be a nuclear-localized protein. Overexpressing GhAFP-like in Arabidopsis thaliana not only showed weaker seed dormancy with insensitivity to ABA, but also changed the expression of some ABA related genes. In addition, a primary root elongation assay showed GhAFP-like may involve in auxin signaling response. The results in this study indicate that GhAFP-like acts as a negative regulator in ABA signaling and is related to dormancy. - Highlights: • GhAFP-like is expessed in dormant corm. • Overexpressing GhAFP-like showed early germination and insensitivity to ABA. • Overexpressing GhAFP-like changed ABI5 downstream genes expression.
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Seed germination of Phillyrea angustifolia L., a species of difficult propagation
Energy Technology Data Exchange (ETDEWEB)
Mira, Sara; Arnal, Alberto; Pérez-García, Félix
2017-11-01
Aim of study: The purpose was to determine the type of dormancy and the optimal germination conditions of Phillyrea angustifolia (Oleaceae) seeds. Area of study: Germination requirements of P. angustifolia seeds collected from wild plants growing in the province of Ávila (Central Spain) were studied. Materials and methods: Seed water uptake was measured. Seeds with and without an endocarp were germinated at different temperatures, and several treatments were tested. Main results: The lignified endocarp interferes mechanically with the emergence of the radicle, and the treatments that achieved the highest germination percentages were the total removal of the endocarp with pliers (84%) or the immersion in liquid nitrogen for 1 min (97%). Scarification with concentrated sulphuric acid did not significantly increase germination compared to the control seeds, and treatments with dry heat or wet heat were detrimental to seed germination. The optimum temperature for germination was 15 ºC. A pre-sowing treatment of soaking in distilled water for 24 h slightly increased germination speed. Neither cold stratification at 5 ºC nor soaking in a gibberellic acid solution improved seed germination. Research highlights: Phillyrea angustifolia seeds have physiological dormancy – that is, the embryo does not have enough growth potential to overcome the mechanical restriction of the lignified endocarp. The seeds do not exhibit physical dormancy, given their water-permeable lignified endocarp. Our results suggest that the optimum germination protocol for P. angustifolia would be the total removal of the endocarp or immersion in liquid nitrogen for 1 min, followed by immersion in distilled water for 24 h and then seed incubation at 15 ºC in light or darkness.
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Sunflower disease compendium: Sunflower botany
The number one challenge for global sunflower production is diseases. Sunflower is the fifth largest oilseed crop grown in temperate and subtropical areas in 72 countries and on every continent, except Antarctica. This has facilitated the spread of diseases globally. Disease control can be by chemic...
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Ordoñez-Salanueva, C A; Orozco-Segovia, A; Canales-Martínez, M; Seal, C E; Pritchard, H W; Flores-Ortiz, C M
2017-11-01
Soil seed banks are essential elements of plant population dynamics, enabling species to maintain genetic variability, withstand periods of adversity and persist over time, including for cactus species. However knowledge of the soil seed bank in cacti is scanty. In this study, over a 5-year period we studied the seed bank dynamics, seedling emergence and nurse plant facilitation of Polaskia chende, an endemic columnar cactus of central Mexico. P. chende seeds were collected for a wild population in Puebla, Mexico. Freshly collected seeds were sown at 25 °C and 12-h photoperiod under white light, far-red light and darkness. The collected seeds were divided in two lots, the first was stored in the laboratory and the second was use to bury seeds in open areas and beneath a shrub canopy. Seeds were exhumed periodically over 5 years. At the same time seeds were sown in open areas and beneath shrub canopies; seedling emergence and survival were recorded over different periods of time for 5 years. The species forms long-term persistent soil seed banks. The timing of seedling emergence via germination in the field was regulated by interaction between light, temperature and soil moisture. Seeds entered secondary dormancy at specific times according to the expression of environmental factors, demonstrating irregular dormancy cycling. Seedling survival of P. chende was improved under Acacia constricta nurse plants. Finally, plant facilitation affected the soil seed bank dynamics as it promoted the formation of a soil seed bank, but not its persistence. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.
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Use a microwave oven to determine the moisture content of sunflower
International Nuclear Information System (INIS)
Backer, L.F.; Walz, A.W.
1987-01-01
Much of the sunflower crop in the major producing areas of the United States requires artificial drying because of late crop maturity. Plant growth regulators permit earlier harvest by accelerating the maturation rate of the plant; research indicates that use of the growth regulator would result in approximately 10-14 days earlier maturation. Effectiveness of the chemical is dependent on timely application at relatively high moisture contents (50 to 55 percent). A rapid means of determining seed moisture content is required so the chemical can be applied at the proper growth stage . Additionally, sunflower is often harvested at moisture contents of more than 17 percent. Most electronic moisture meters are not calibrated for moisture contents this high and the accuracy of most moisture meters decreases with increasing moisture content. A recent study has shown that a conventional microwave oven can successfully be used to very rapidly determine the moisture content of high moisture sunflower seeds to indicate proper growth stage for the application of plant growth regulators. The microwave oven could also be used with reasonable accuracy to check harvest moisture content down to about 15 percent. At lower moisture contents, it would be advisable to use a calibrated electronic moisture meter
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Effects of environmental variation during seed production on seed dormancy and germination.
Penfield, Steven; MacGregor, Dana R
2017-02-01
The environment during seed production has major impacts on the behaviour of progeny seeds. It can be shown that for annual plants temperature perception over the whole life history of the mother can affect the germination rate of progeny, and instances have been documented where these affects cross whole generations. Here we discuss the current state of knowledge of signal transduction pathways controlling environmental responses during seed production, focusing both on events that take place in the mother plant and those that occur directly as a result of environmental responses in the developing zygote. We show that seed production environment effects are complex, involving overlapping gene networks active independently in fruit, seed coat, and zygotic tissues that can be deconstructed using careful physiology alongside molecular and genetic experiments. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
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Effect of seed collection times and pretreatment methods on ...
African Journals Online (AJOL)
STORAGESEVER
2008-08-18
Aug 18, 2008 ... Several basic methods are used to overcome seed- coat dormancy in ... The experiment on seed pretreatment were conducted at Forestry. Research ..... applicability to rural areas where these trees are planted may be limited. .... Forestry. Research News: Indicators and Tools for Restoration & Sustainable.
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Genetic analysis of sunflower chlorophyll mutants
International Nuclear Information System (INIS)
Mashkina, E.V.; Guskov, E.P.
2001-01-01
The method of getting the chlorophyll mutations in sunflower was developed by Y.D. Beletskii in 1969 with the use of N-nitroso-N-methylurea (NMH). Certain concentrations of NMH are known to induce plastid mutations in growing seeds, and their yield depends on the duration of the exposure. The given work presented studies on the influence of rifampicin (R) and 2,4-dinitrophenol (DNP) on the genetic activity NMH, as an inductor of plastid and nuclear mutations
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Effect of pre-treatments on seed germination of Parkia biglobosa ...
African Journals Online (AJOL)
Effect of pre-treatments on seed germination of Parkia biglobosa (Benth) ... There has been emphasis on the use of indigenous tree species to check land ... out to investigate the most effective pre-sowing treatments to break seed dormancy and to ... Matured seeds of P. biglobosa were collected from farmers at Mbalagh ...
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Seed dormancy and resistance to seed decay organisms are fundamental ecological strategies for weed seed persistence in the weed seed-bank. Seeds have well-established physical, chemical, and biological defense mechanisms that protect their food reserves from decay-inducing organisms and herbivores....
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Directory of Open Access Journals (Sweden)
Diego Fernando Escobar Escobar
2013-06-01
Full Text Available Alibertia patinoi (Rubiaceae. Alibertia patinoi (Rubiaceae is of economic and cultural importance for communities in the Colombian Pacific and Amazon regions, where it is cultivated and mature fruits are highly appreciated and consumed. Since there is a lack of knowledge of the seed physiology of this species, we describe here the germination behavior and morphometry of seeds of Alibertia patinoi, and relate them to its habitat. Fruits were collected from a mixed food crop and a commercial plantation in Guaimía village, Buenaventura, Colombia, a tropical rain forest area. We measured length, width, thickness, mass (n=1 400, and moisture content of seeds (n=252. Primary dormancy tests were conducted (n=200, followed by imbibition (n=252 and germination dynamics, under different conditions of light and temperature specific to understory and forest clearings (n=300 seeds. Finally, seed storage behavior was established (n=100 seeds. We observed that size and mass of seeds had a narrow range of values that did not differ within or among fruits and that the species did not exhibit primary dormancy. The seeds are recalcitrant, and recently harvested seeds exhibited higher seed moisture content (ca. 44% and continuous metabolism. The seed germination percentage was observed to be higher under the specific dense canopy forest light and temperature conditions; furthermore, neither enriched far-red light nor darkness conditions inhibited germination. We concluded that rapid germination could be the establishment strategy of this species. Also, the physiological traits (i.e., rapid germination rate, low germination requirements, absence of primary dormancy, and recalcitrant behavior and seed size and mass, suggest that A. patinoi is adapted to conditions of mature tropical rain forests.
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Characterization of the Bulgarian sunflower hybrid Valin
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G. Georgiev
2016-09-01
Full Text Available Abstract. A male sterile two-linear sunflower hybrid was developed at Dobrudzha Agricultural Institute – General Toshevo using the method of inter-linear hybridization. The mother component is line 10517 which possesses cytoplasmic male sterility, and the father component is line 10595R, a fertility restorer of branched type. Both parental forms have very good general and specific combining ability. Hybrid Valin is medium early, with vegetation period of 110 – 115 days, plant height 165 – 175 cm and head diameter 17 – 18 cm. The percent of kernel in seed is within the range of 65 – 73%. Seeds have absolute weight 50 – 55 g, and oil content in seed is 46 – 50%. The hybrid is resistant to lodging and moderately resistant to phoma and phomopsis. The resistance to downy mildew is as high as 95 % up to race 700, and the resistance to the parasite Orobanche is 100% (races A-F. In the breeding fields of DAI the hybrid went through threeyear testing according to a scheme and growing technology approved for this crop. During the first two years of the control testing it exceeded the mean standard by seed yield with 11.0% and 14.4%, respectively. During the third year, hybrid Valin was above the mean standard with 10.9% by seed yield and with 6.6% by oil yield in a unified competitive varietal testing. The maximum yield obtained at DAI was 4483 kg/ha, and the maximum oil content was 50.1%. In 2007 and 2008 hybrid Valin went through official testing within the structure of the Executive Agency of Variety Testing, Field Inspection and Seed Control of Bulgaria. By the index seed yield, the exceeding of the mean standard was 23.6 % in the first year, and in the second the yield was with 1.4 % below the standard. Oil content was a little below the standard in both years. The aim of this investigation was to make as full as possible a characterization of the new registered sunflower hybrid Valin on the base of biological, phytopatological and
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Directory of Open Access Journals (Sweden)
Maryam GOLABADI
2015-11-01
Full Text Available The main objective underlying sunflower breeding programs is to develop high-yielding productive F1 hybrid cultivars. This study was conducted to investigate the genetic control of some agro-morphological traits of new sunflower F1 hybrids. For this purpose, fourteen inbred lines of sunflower were crossed with three male sterile inbred lines. Their hybrids (14 hybrids were then evaluated against three control cultivars. The data thus obtained were analyzed using the nested model (North Carolina Design І as a completely randomized block design (CRBD with four replications. Analysis of variance showed that the hybrids were significantly different in all the traits studied, except for head and stem diameters. From among the hybrids evaluated, Cms19 × Rn1-81 was found to have the highest seed yield and oil content. Cluster analysis classified the hybrids into four different groups. Genetic analysis showed that days to maturity, seed weight, and oil content (% were under the additive gene action. Breeding strategies based on selection could be suggested for the improvement of these traits. Head angle, head diameter, seed yield, and oil yield were under the dominance gene action; breeding based on hybridization methods is, therefore, proposed for these traits. Finally, both additive and dominance gene actions were observed to play important roles in the genetic control of plant height and stem diameter.
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Kasmynin G. G.
2014-01-01
The basic amount of oilseeds in the Russian Federation, including the Stavropol region is produced by sunflowers. Using the best ways and methods of soil cultivation and improving the technology of sunflower cultivation in relation to specific growing conditions - the main way to increase the yield and gross yield of seeds of this valuable crop
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Correlation and path-cofficient analysis of seed yield and yield ...
African Journals Online (AJOL)
This study was undertaken in order to determine the association among yield components and their direct and indirect effects on the seed yield of confectionery sunflower. 36 confectionery sunflower populations originated from different regions of Northwest Iran were characterized using 11 agromorphological traits ...
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Optimizing conditions for enzymatic extraction of sunflower oil
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Badr, F. H.
1992-10-01
Full Text Available Sunflower seed oil was extracted with an enzymatic processes using different hydrolytic enzymes: cellulase, hemicellulase, animal proteinase, acid proteinase, pectinase and pectinex, as compared to enzyme - free aqueous extraction. All the hydrolytic enzymes enhanced oil extraction from sunflower seeds. The most optimal conditions for oil extraction from sunflower seeds were: 2% enzyme concentration, 30% substrate concentration and 3 hrs period. Using Boganov and Buchkov equation showed that time must be prolonged to get higher yields. The maximum yield during 3 hrs extraction with enzymatic process ranged between 44,5%-57,1% of the soxhlet extractable oil. The potency of the investigated enzymes in extracting oil was in the following order: acid proteinase > cellulase > hemicellulase > animal proteinase > pectinex > pectinase when compared at the previous optimal conditions.
Aceite de semilla de girasol fue extraído mediante un proceso enzimático usando diferentes enzimas hidrolíticos: celulasa, hemicelulasa, proteinasa animal, proteinasa acida, pectinasa y pectinex, comparando con la extracción acuosa libre de enzima. Todos los enzimas hidrolíticos incrementan la extracción de aceites de semilla de girasol. Las condiciones óptimas para la extracción de aceite a partir de semillas de girasol fueron: 2% de concentración de enzima, 30% de concentración de sustrato y un período de 3 horas. La ecuación de Boganov y Buchkov mostró que el tiempo debe ser prolongado para alcanzar altos rendimientos. El máximo rendimiento durante tres horas de extracción con proceso enzimático osciló entre el 44,5%-57,1% del aceite extraído con soxhlet. La potencia de los enzimas investigados en la extracción de aceite siguió el orden: proteinasa acida > celulasa > hemicelulasa > proteinasa animal > pectinex > pectinasa cuando fue previamente comparado con las condiciones óptimas. -
Ueno, Kotomi; Furumoto, Toshio; Umeda, Shuhei; Mizutani, Masaharu; Takikawa, Hirosato; Batchvarova, Rossitza; Sugimoto, Yukihiro
2014-12-01
Root exudates of sunflower (Helianthus annuus L.) line 2607A induced germination of seeds of root parasitic weeds Striga hermonthica, Orobanche cumana, Orobanche minor, Orobanche crenata, and Phelipanche aegyptiaca. Bioassay-guided purification led to the isolation of a germination stimulant designated as heliolactone. FT-MS analysis indicated a molecular formula of C20H24O6. Detailed NMR spectroscopic studies established a methylfuranone group, a common structural component of strigolactones connected to a methyl ester of a C14 carboxylic acid via an enol ether bridge. The cyclohexenone ring is identical to that of 3-oxo-α-ionol and the other part of the molecule corresponds to an oxidized carlactone at C-19. It is a carlactone-type molecule and functions as a germination stimulant for seeds of root parasitic weeds. Heliolactone induced seed germination of the above mentioned root parasitic weeds, while dehydrocostus lactone and costunolide, sesquiterpene lactones isolated from sunflower root exudates, were effective only on O. cumana and O. minor. Heliolactone production in aquacultures increased when sunflower seedlings were grown hydroponically in tap water and decreased on supplementation of the culture with either phosphorus or nitrogen. Costunolide, on the other hand, was detected at a higher concentration in well-nourished medium as opposed to nutrient-deficient media, thus suggesting a contrasting contribution of heliolactone and the sesquiterpene lactone to the germination of O. cumana under different soil fertility levels. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Chemical composition of open pollinated and hybrid population of sunflower (helianthus annuus l.)
International Nuclear Information System (INIS)
Nisar, M.; Hussain, S.; Nausheen, A.; Siddique, F.
2011-01-01
Sunflower is the world fourth most important sources of edible oil. A lot of work has been done for varietal improvement through conventional breeding in Pakistan. Sunflower is the cash crop and is easily adapted to many region of Pakistan, genetic and agronomical improvement was needed so that economically valuable crop could be harvested. In the present work, 16 cultivars (open pollinated population 'OPP' and hybrid population 'HP' eight each) of sunflower was evaluated. The study was aimed at evaluating the mineral composition, estimation of moisture contents, measuring electrical conductivity and 100 seeds weight. The mineral composition was fractionated though Atomic Absorption Spectrometer, which indicate that Zn +2 was 8.54 and 9.35%; Cu/sup +2/ 0.5 and 0.02%; Mn/sup +2/ 3.48 and 9.72%; Co/sup +2/ 18.67 and 16.81%; Mg/sup +2/ 68.27 and 83.53%; Fe/sup +3/ 4.32 and 4.35% were estimated in HP and OPP respectively. Similarly, moisture contents 6.26 and 6.78%, and 1000-seeds weight 510.8 and 598 g were calculated in the HP and OPP respectively. In comparative picture the mineral concentration, moisture contents and 100 seeds weight in open pollinated population were high as compared to hybrid. A total of 11.7 % genetic diversity was observed in mineral composition of both the populations. The EC was high in HP ranging from 70. 85-137.8, while comparatively low in OPP ranged 46.81 - 120.18. (author)
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Directory of Open Access Journals (Sweden)
F. Dohme-Meier
2012-01-01
Full Text Available An experiment was conducted to compare the effect of the same amount of 18:2 offered either as 18:2n-6 or as a mixture of unprotected 18:2c9t11 and 18:2t10c12 on feed intake, milk components as well as plasma and milk fatty acid profile. Fifteen cows were blocked by milk yield and milk fat percentage and within block assigned randomly to 1 of 3 treatments (n = 5. Each cow passed a 12-d adjustment period (AP on a basal diet. After the AP cows received 1 of 3 supplements during an 18-d experimental period (EP. The supplements contained either 1.0 kg ground sunflower seeds (S, 0.5 kg conjugated linoleic acid (CLA-oil (C or 0.75 kg of a mixture of ground sunflower seeds and CLA-oil (2:1; SC. All 3 supplements contained the same amount of 18:2 either as CLA (∑18:2c9t11+18:2t10c12, 1:1 or as 18:2c9c12. During the last 2 d of AP and the last 4 d of EP feed intake and milk yield were recorded daily and milk samples were collected at each milking. Blood samples were collected from the jugular vein on d 11 of AP and d 15 and 18 of EP. The 18:2 intake increased in all treatments from AP to EP. Regardless of the amount of supplemented CLA, the milk fat percentage decreased by 2.35 and 2.10%-units in treatment C and SC, respectively, whereas in the treatment S the decrease was with 0.99%-unit less pronounced. Thus, C and SC cows excreted daily a lower amount of milk fat than S cows. The concentration of trans 18:1 in the plasma and the milk increased from AP to EP and increased with increasing dietary CLA supply. While the concentration of 18:2c9t11 and 18:2t10c12 in the plasma and that of 18:2t10c12 in the milk paralleled dietary supply, the level of 18:2c9t11 in the milk was similar in C and CS but still lower in S. Although the dietary concentration of CLA was highest in treatment C, the partial replacement of CLA by sunflower seeds had a similar inhibitory effect on milk fat synthesis. Comparable 18:2c9t11 levels in the milk in both CLA treatments
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THE BIOLOGICAL CYCLE OF SUNFLOWER BROOMRAPE
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DUCA Maria
2013-12-01
Full Text Available Orobanchaceae is a dicot family, which consists of annual and perennial plants distributing from tropical to subarctic regions, predominately in temperate regions. Broomrape (Orobanche cumana Wallr. = Orobanche cernua Loefl. is a parasitic angiosperm that has been causing a great deal of damage to sunflower production in many countries, including Republic of Moldova. This parasitic angiosperm depends entirely on the host for its supply of water and nutrients. A thorough understanding of its biology, including detailed knowledge of the specific mechanisms of parasitism, is needed in order to develop novel control methods. Some main developmental steps are described for the root parasites: seed conditioning and germination, haustorium formation, penetration into host tissues, maturation of the parasite plant, and seed production. All these stages were studied in artificial and natural conditions.
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da Costa Marques, Mônica Regina; de Souza, Paulo Sérgio Alves; Rigo, Michelle Machado; Cerqueira, Alexandre Andrade; de Paiva, Julieta L; Merçon, Fábio; Perez, Daniel Vidal
2015-10-01
This study aims to evaluate possible toxic effects of oil and other contaminants from oilfield-produced water from oil exploration and production, on seed germination, and seedling development of sunflower (Helianthus annuus L.). In comparison, as treated by electroflocculation, oilfield-produced water, with lower oil and organic matter content, was also used. Electroflocculation treatment of oilfield-produced water achieved significant removals of chemical oxygen demand (COD) (94 %), oil and grease (O&G) (96 %), color (97 %), and turbidity (99 %). Different O&G, COD, and salt levels of untreated and treated oilfield-produced water did not influence germination process and seedling biomass production. Normal seedlings percentage and vigor tended to decrease more intensely in O&G and COD levels, higher than 337.5 mg L(-1) and 1321 mg O2 L(-1), respectively, using untreated oilfield-produced water. These results indicate that this industrial effluent must be treated, in order to not affect adversely seedling development. This way, electroflocculation treatment appears as an interesting alternative to removing oil and soluble organic matter in excess from oilfield-produced water improving sunflower's seedling development and providing a friendly environmental destination for this wastewater, reducing its potential to harm water resources, soil, and biota.
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International Nuclear Information System (INIS)
Massas, I.; Skarlou, C.; Anoussis, J.; Haidouti, C.; Arapis, G.
1999-01-01
The effect of soil pH on 134 Cs TFs as well as the fate of 134 Cs in the extracted oil was studied in a greenhouse experiment with soybean and sunflower plants. A soil with pH 4.2 was used as a basis and its pH value has increased to 5.7, 6.5 and 7.6 (by the addition of different amounts of Ca(OH) 2 ). The lowest TF value was observed in the calcareous soil (pH 7.6), while the highest in the lowest pH (4.2) for the vegetative part and in the pH 6.5 for the edible part for both studied plants. TFs were practically the same for soya plants grown on the three lowest soil pH and reduced significantly only at pH 7.6 for either pods or other plant material. However, the lowest/highest TF was ∼ 4 for pods and ∼ 6 for the other plant material. For the sunflower plants while TFs for other plant material reduced from lowest to highest soil pH by only a factor of 2, for the seeds TFs remained rather constant. The difference in TF between the two studied species in each soil pH was in some cases higher than the difference due to pH effect. When an oil fraction (∼ 20 %) was extracted from seeds of both plants, no 134 Cs was detected. Refs. 4 (author)
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Franke, Bastian; James, Amy M; Mobli, Mehdi; Colgrave, Michelle L; Mylne, Joshua S; Rosengren, K Johan
2017-07-28
Seed storage proteins are both an important source of nutrition for humans and essential for seedling establishment. Interestingly, unusual napin-type 2S seed storage albumin precursors in sunflowers contain a sequence that is released as a macrocyclic peptide during post-translational processing. The mechanism by which such peptides emerge from linear precursor proteins has received increased attention; however, the structural characterization of intact precursor proteins has been limited. Here, we report the 3D NMR structure of the Helianthus annuus PawS1 ( p repro a lbumin w ith s unflower trypsin inhibitor- 1 ) and provide new insights into the processing of this remarkable dual-destiny protein. In seeds, PawS1 is matured by asparaginyl endopeptidases (AEPs) into the cyclic peptide SFTI-1 ( s un f lower t rypsin i nhibitor- 1 ) and a heterodimeric 2S albumin. The structure of PawS1 revealed that SFTI-1 and the albumin are independently folded into well-defined domains separated by a flexible linker. PawS1 was cleaved in vitro with recombinant sunflower HaAEP1 and in situ using a sunflower seed extract in a way that resembled the expected in vivo cleavages. Recombinant HaAEP1 cleaved PawS1 at multiple positions, and in situ , its flexible linker was removed, yielding fully mature heterodimeric albumin. Liberation and cyclization of SFTI-1, however, was inefficient, suggesting that specific seed conditions or components may be required for in vivo biosynthesis of SFTI-1. In summary, this study has revealed the 3D structure of a macrocyclic precursor protein and provided important mechanistic insights into the maturation of sunflower proalbumins into an albumin and a macrocyclic peptide. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
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Study of homeopathic drugs on seed germination and fungal growth
International Nuclear Information System (INIS)
Hanif, A.; Dawar, S.
2016-01-01
In vitro, seeds of mungbean, sunflower, okra and mashbean were treated with homeopathic drugs namely Arnica montana and Thuja occidentalis (30C) were evaluated against root rot fungi. Different concentrations like 100, 75 and 50% v/v were tested to investigate seeds germination and inhibition of root rot fungi such as Fusarium oxysporum, Rhizoctonia solani and Macrophomina phaseolina. Results indicated that treated seeds of mungbean, sunflower, okra and mashbean with pure homeopathic drugs (100% v/v) by A. montana and T. occidentalis (30C) showed complete germination (100%), greater root length and excellent inhibition of root infecting pathogens. However, tested seeds treated with 75 and 50% v/v concentrations (prepared from 30C) by homeopathic drugs, respectively recorded significant increase in germination, root length and maximum zone of inhibition. (author)
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Regularities of filtration of sunflower oil with the use of vibroacoustic exposure
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S. A. Bredikhin
2017-01-01
Full Text Available The residue in sunflower oil is a dispersed phase consisting of particulate products grinding sunflower seeds in the form of particles of the pulp, oil cake, meal, residual quantities of metals, pesticides. In the recycling process they are in the oil in suspension and negatively affect its quality. For research an experimental setup was developed allowing to change the angle of inclination of the filter element. The regularities of filtration were determined without preliminary purification of sunflower oil by centrifugation and after centrifugation. It is established, the contamination of centrifuged oil in the initial period is 14.6 times lower. After 10 minutes of treatment, it decreases by 62%, after 20 minutes – by 79.4%. With a 30-minute treatment, particles of 0.005-0.1 mm in size are removed to 90%, which is approximated to the refined oil in terms of contamination. The influence of vibration-acoustic action on sunflower oil during its filtration is shown. At the last stage of production, the peroxide index is reduced to 2-3 moles of active oxygen, and after 3 months of storage – from 11.8 to 7.7, which according to GOST corresponds to the highest-grade oil. The regularities of the filtration without pre-treatment of sunflower oil by centrifugation and after centrifugation. Shows the effect of vibroacoustic exposure on sunflower oil when filtering. The obtained data on the change of qualitative parameters of sunflower oil during its filtration in the field of vibroacoustic impact.
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Andrea Pavoni
2015-06-01
Full Text Available Ai Weiwei’s art installation Kui Hua Zi [Sunflower Seeds] took place between 2010 and 2011 in the gigantic Turbine Hall of the Tate Modern Gallery, in London. It consisted of 100 millions hand-crafted porcelain seeds made in Jingdezhen, China.1 An uneven surface to dive into, a haptic space of undulating vision, rustling steps, unusual horizontality, a meaningless quicksand where the separation between artwork and spectator is engulfed, the immunity of distant contemplation denied.
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Effect of water stress on yield and yield components of sunflower ...
African Journals Online (AJOL)
A field experiment during year 2009 was conducted in the research station of the University of Tehran, College of Abouraihan in Pakdasht region, Iran. The study was aimed to investigate the effect of water stress on seed yield, yield component and some quantitative traits of four sunflower hybrids namely Azargol, Alstar, ...
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7 CFR 361.6 - Noxious weed seeds.
2010-01-01
... aciculatus (Retzius) Trinius Commelina benghalensis L. Crupina vulgaris Cassini Cuscuta spp. Digitaria...), nightshade (Solanaceae), and sunflower (Asteraceae). (5) Dodder (Cuscuta spp.) seeds devoid of embryos and...
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Hossein NAZARLI
2010-12-01
Full Text Available In many part of Iran, the reproductive growth stages of sunflower (Helianthus annuus L. are exposed to water deficit stress. Therefore, the investigation of irrigation management in the farm conditions is a necessary element for increasing irrigation efficiency and decreasing water losses. The objective of present study was to investigate the effect of different rates of super absorbent polymer and levels of water stress on water use efficiency (WUE, yield and some morphological traits of sunflower (cultivar Master. Factorial experiment was carried out in completely randomized design with 3 replications. Factors were water stress in three levels (irrigation in 0.75; 0.50 and 0.25% of field capacity and super absorbent polymer in five levels (0; 0.75; 0.150; 2.25; 3 g/kg of soil. Super absorbent polymer was added in eight leaves stage of sunflower to pots in deepness of roots development. Water stress treatment was also applied in this growth stage of sunflower. For stress application, pots were weighted every day and irrigated when soil water received to 0.75; 0.50 and 0.25 of field capacity, respectively. The results of ANOVA indicated that the effect of different rates of super absorbent polymer and different rates of consumed water in all traits were significant. ANOVA also revealed that the interactive effects of two mentioned factors were significant except for seed yield trait. Polynomial model based on the ANOVA results was fitted for each trait. The results indicated that water stress significantly convert in decreasing the number of leaves per plant, chlorophyll content, 100 weight of seeds, seed yield and WUE in sunflower, whereas the application of super absorbent polymer moderated the negative effect of deficit irrigation, especially in high rates of polymer (2.25 and 3 g/kg of soil. The above mentioned rates of polymer have the best effect to all characteristics of sunflower in all levels of water stress treatment. The findings
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Alleviate Seed Ageing Effects in Silybum marianum by Application of Hormone Seed Priming
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Seyed Ata SIADAT
2015-09-01
Full Text Available Most of the medicinal plants have seed dormancy or poor seed germination. This is due to their natural compounds or their morphological structure. Existence of such mechanisms makes the seeds able to endure harsh environments, stressful conditions or natural ageing. Different seed enhancement treatments were proposed in order to improve seed germination. In this study, it was examined Silybum marianum seed longevity (0, 48 and 72 hour of ageing and the response to seed priming when using different concentrations of cytokinin (50, 200, 350 and 500 ppm and different duration of treatment (8, 12 and 24 hour. Results revealed that ageing could be successfully alleviated using seed priming. Seed ageing significantly affected seed germination and vigour. Application of cytokinin considerably improved seed vigour in aged and non aged seeds. The most effective seed priming treatment was with 500 ppm cytokine, with the duration of 24 hours. In conclusion, it can be recommend the used of plant growth regulators like cytokine, as a good priming agent, to recover losses of seed quality and improve germination characteristics.
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Silvia Rahe Pereira
2013-02-01
Full Text Available O objetivo deste trabalho foi avaliar a influência de tratamentos de superação da dormência de sementes sobre a taxa e o tempo de emergência de espécies arbóreas de Fabaceae, e sobre seu estabelecimento, quando reintroduzidas em pastagem, no Cerrado. Foram realizados experimentos em casa de vegetação e em campo (pastagem de Urochloa brizantha, com as espécies Mimosa caesalpiniifolia, Peltophorum dubium, Pterogyne nitens, Dimorphandra mollis, Copaifera langsdorffii e Hymenaea stigonocarpa, submetidas ou não aos seguintes tratamentos de superação de dormência: D. mollis e H. stigonocarpa, escarificação mecânica; C. langsdorffii e M. caesalpiniifolia, escarificação química com H2SO4; P. nitens, punção do tegumento; e P. dubium, imersão em água a 80ºC. O estabelecimento em campo foi monitorado por 21 meses. A superação de dormência promoveu, em casa de vegetação, maior emergência de quatro das seis espécies avaliadas, e, no campo, de cinco espécies. Além disso, reduziu o tempo de emergência das espécies e aumentou o recrutamento de M. caesalpiniifolia, P. nitens, D. mollis e H. stigonocarpa, aos 127 dias, e de H. stigonocarpa aos 659 dias. Os tratamentos de superação de dormência podem aumentar a eficiência da semeadura direta, em projetos de restauração de áreas degradadas no Cerrado, ao promover maior emergência das sementes e o estabelecimento das plantas.The objective of this work was to evaluate the influence of seed dormancy overcoming treatments on the rate and time of emergence of Fabaceae tree species, and on their recruitment when reintroduced in a tropical pasture, in the Brazilian Cerrado. Experiments were carried out in greenhouse and field (Urochloa brizantha pasture, with the species Mimosa caesalpiniifolia, Peltophorum dubium, Pterogyne nitens, Dimorphandra mollis, Copaifera langsdorffii and Hymenaea stigonocarpa, subjected or not to the following treatments of dormancy break: D. mollis and
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van Zanten, Martijn; Koini, Maria A; Geyer, Regina; Liu, Yongxiu; Brambilla, Vittoria; Bartels, Dorothea; Koornneef, Maarten; Fransz, Paul; Soppe, Wim J J
2011-12-13
Most plant species rely on seeds for their dispersal and survival under unfavorable environmental conditions. Seeds are characterized by their low moisture content and significantly reduced metabolic activities. During the maturation phase, seeds accumulate storage reserves and become desiccation-tolerant and dormant. Growth is resumed after release of dormancy and the occurrence of favorable environmental conditions. Here we show that embryonic cotyledon nuclei of Arabidopsis thaliana seeds have a significantly reduced nuclear size, which is established at the beginning of seed maturation. In addition, the chromatin of embryonic cotyledon nuclei from mature seeds is highly condensed. Nuclei regain their size and chromatin condensation level during germination. The reduction in nuclear size is controlled by the seed maturation regulator ABSCISIC ACID-INSENSITIVE 3, and the increase during germination requires two predicted nuclear matrix proteins, LITTLE NUCLEI 1 and LITTLE NUCLEI 2. Our results suggest that the specific properties of nuclei in ripe seeds are an adaptation to desiccation, independent of dormancy. We conclude that the changes in nuclear size and chromatin condensation in seeds are independent, developmentally controlled processes.
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Liu, Yang; Fang, Jun; Xu, Fan; Chu, Jinfang; Yan, Cunyu; Schläppi, Michael R; Wang, Youping; Chu, Chengcai
2014-06-20
Seed dormancy is an important agronomic trait in cereals. Using deep dormant (N22), medium dormant (ZH11), and non-dormant (G46B) rice cultivars, we correlated seed dormancy phenotypes with abscisic acid (ABA) and gibberellin (GA) metabolism gene expression profiles and phytohormone levels during seed development and imbibition. A time course analysis of ABA and GA content during seed development showed that N22 had a high ABA level at early and middle seed developmental stages, while at late developmental stage it declined to the level of ZH11; however, its ABA/GA ratio maintained at a high level throughout seed development. By contrast, G46B had the lowest ABA content during seed development though at early developmental stage its ABA level was close to that of ZH11, and its ABA/GA ratio peaked at late developmental stage that was at the same level of ZH11. Compared with N22 and G46B, ZH11 had an even and medium ABA level during seed development and its ABA/GA ratio peaked at the middle developmental stage. Moreover, the seed development time-point having high ABA/GA ratio also had relatively high transcript levels for key genes in ABA and GA metabolism pathways across three cultivars. These indicated that the embryo-imposed dormancy has been induced before the late developmental stage and is determined by ABA/GA ratio. A similar analysis during seed imbibition showed that ABA was synthesized in different degrees for the three cultivars. In addition, water uptake assay for intact mature seeds suggested that water could permeate through husk barrier into seed embryo for all three cultivars; however, all three cultivars showed distinct colors by vanillin-staining indicative of the existence of flavans in their husks, which are dormancy inhibition compounds responsible for the husk-imposed dormancy. Copyright © 2014. Published by Elsevier Ltd.
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DETERMINATION OF INHIBITORS, DORMANCY BREAKING AND SEED HEALTH IN CUTIEIRA
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José Maria Gomes Neves2
2013-12-01
was completely randomized, factorial 2 x 5, with two types of seed from freshly harvested fruits and remnants and five pre-germination treatments. The seed coat removal promotes increased germination and seed vigor derived from harvested fruits. Fungi identified in the cutieira seeds were Aspergillus niger, Aspergillus flavus, Penicillium sp. and Rhizopus sp.
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mohamad taghi naseri poor yazdi
2009-06-01
Full Text Available Allelopathic effects of barley straw and root on germination and growth of maize, sugar beet, and sunflower were investigated under glasshouse and laboratory experiments in Faculty of Agriculture, Ferdowsi University of Mashhad in 2006. The glasshouse experiment was designed based on randomized complete block design with three replications, treatments included: 0, 200, 400, 600 g/m² of grounded barley straw and also 0 and 50 g/m2 barley root. A laboratory experiment was carried out in order to study the effect of different concentrations of barley water extracts on germination and seedling characteristics of corn, sugar beet and sunflower. Treatments in laboratory trial included 0, 33, 50 and 100 percent of barley extracts. Results showed that leaf area of corn was significantly affected by barley straw treatments. Shoot dry matter and seed weight per plant in corn , leaf and tuber weight in sugar beet and leaf , stem weights , plant per plant in corn , leaf and tuber weight in sugar beet and leaf, stem weights, plant height, head diameter, head weight and seed weight in sunflower were significantly higher in treatment of 50g/m² barley roots. Crop seed germination decreased with increasing the amount of barley straw. The best germination response to barley extract was observed in corn. Maize radicle weight was significantly decreased with increasing concentration of barley water extract.
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The effects of NaCl priming on salt tolerance in sunflower ...
African Journals Online (AJOL)
This experiment was conducted to evaluate the effects of NaCl priming with KNO3 on the germination traits and seedling growth of four Helianthus annuus L. cultivars under salinity conditions. Seeds of four spring sunflower (Armawireski, Airfloure, Alestar and Ismailli) were primed with KNO3 (-1.0 M Pa) for 24 h in ...
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Transcriptome Analysis of Two Different Developmental Stages of Paeonia lactiflora Seeds
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Yonglei Ma
2017-01-01
Full Text Available Paeonia lactiflora is a herbaceous flower in the family Paeoniaceae with both hypocotyl and epicotyl dormant seeds. We used high-throughput transcriptome sequencing on two different developmental stages of P. lactiflora seeds to identify seed dormancy and germination-related genes. We performed de novo assembly and annotated a total of 123,577 unigenes, which encoded 24,688 putative proteins with 47 GO categories. A total of 10,714 unigenes were annotated in the KEGG database, and 258 pathways were involved in the annotations. A total of 1795 genes were differentially expressed in the functional enrichment analysis. The key genes for seed germination and dormancy, such as GAI1 and ARF, were confirmed by quantitative reverse transcription-polymerase chain reaction analysis. This is the first report of sequencing the P. lactiflora seed transcriptome. Our results provide fundamental frame work and technical support for further selective breeding and cultivation of Paeonia. Our transcriptomic data also serves as the basis for future genetics and genomics research on Paeonia and its closely related species.
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Bouwmeester, H.J.
1990-01-01
Weeds cause considerable losses in horticultural and agricultural crops. Weeds are still predominantly controlled with herbicides. To reduce the use of chemicals, a better understanding of the biology of weeds is required. In this thesis the effect of environmental conditions on dormancy
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Directory of Open Access Journals (Sweden)
Giovanna Cucci
2007-12-01
Full Text Available The agricultural use of olive processing waste is a strategic resource in the integrated management of the agricultural system as it satisfies the two objectives of evacuating the olive-processing residue and using it beneficially for agricultural purposes. For such aims, a research was conducted in Bari (South of Italy to study the effects of the incorporation into the soil of increasing amounts of non-fermented wet pomace (WP (0, 17.5, 35, 70, 105, 140, 175, 210 Mg ha-1 on the oil yield and acid profile of sunflower seeds. The results obtained point out that the seed yield was negatively affected by the application of WP starting from 70 Mg ha-1; an opposite trend was observed for the seed oil yield. The incorporation of WP has also affected the oil fatty acids’ composition. Oleic and linoleic acids, the principal fatty acids (beyond 90% of total fatty acids, showed significant variations: from the control treatment to the one receiving the maximum application of waste, oleic acid decreased (-5.4%, linoleic acid increased (+ 6.6%, and the saturated fatty acids fraction decreased (-7.6%.
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Mani, Dinesh; Sharma, Bechan; Kumar, Chitranjan
2007-07-01
An investigation was conducted to study the interaction between Cd and Ca, Zn and organic matter for Cd-phytoremediation in sunflower on the alluvium soil of the Sheila Dhar Institute (SDI) experimental farm, Allahabad (India). Application of 40 ppm Zn produced 11.18% extra dry matter (DM) content and 5.8% extra seed yield over the control. We recommended 1.0% Ca, 40 ppm Zn and 20 tons/ha of compost to enhance dry matter yield and diminish the Cd accumulation in 15 ppm Cd- ethylenediaminetetraacetic (EDTA)-treated plots up to 1/12 folds in sunflower (phytoremediation of Cd-contaminated soil through soil-plant-rhizospheric processes.
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The Application of Neural Networks in Balancing Production of Crude Sunflower Oil and Meal
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Bojan Ivetic
2014-08-01
Full Text Available The aim of the research is to predict specific output characteristics of half finished goods (crude sunflower oil and meal on the basis of specific input variables (quality and composition of sunflower seeds, with the help of artificial neural networks. This is an attempt to predict the amount much more precisely than is the case with technological calculations commonly used in the oil industry. All input variables are representing the data received by the laboratory, and the output variables except category % of oil which is obtained by measuring the physical quantity of produced crude sunflower oil and sunflower consumed quantity of the processing quality. The correct prediction of the output variables contributes to better sales planning, production of sunflower oil, and better use of storage. Also, the correct prediction of technological results of the quality of crude oil and meal provides timely response and also preventing getting rancid and poor-quality oil, timely categorizing meal, which leads to proper planning and sales to the rational utilization of storage space, allows timely response technologists and prevents the growth of microorganisms in the meal.
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International Nuclear Information System (INIS)
Semerci, A.
2012-01-01
In this study the effects of both premium support application on sunflower cultivation area, production amount and support payments on producer income are investigated. In this study it is concluded that premium supports are inefficient on increasing sunflower cultivation area and production whereas it is concluded that it has an important role on producer income and in the determination of the market price. In fact, from a survey that we have carried out, it emerges that the area-based support (diesel oil, fertilizer etc. support) together with premium support increase the revenue of sunflower up to 27.74% per unit area and the gross profit in the proportion of 98.87%. This study indicates that in order to increase the sunflower production in Turkey the amounts of sunflower premium support, diesel oil and fertilizer should be rearranged in compliance with current market conditions. Moreover, for other agricultural products, the use of certified seed should also be included into agricultural support programmes. Production on well irrigated areas should be widened and the use of oil crops varieties with high oil ratio should be extended. (author)
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Gineo, Wayne M.; Sundquist, W. Burt
1981-01-01
This report is concerned with a discussion of the sunflower production sector. It summarizes and discusses the North American sunflower production sector in terms of area, acreage, total production, yields and prices. In addition, a preliminary evaluation of the potential level of sunflower production is made.
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Borneo: The new NS sunflower confectionary type hybrid
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Hladni Nada
2009-01-01
Full Text Available At the Institute of Field and Vegetable Crops in Novi Sad, beside the basic direction in sunflower breeding, the creation of standard hybrids with high oil content with high seed and oil yield, hybrids are being created for special confectionery purposes directed towards the final kernel products. In this program, apart from breeding in order to improve main seed yield components, special attention is given to the increase of protein content and the quality with the decrease of seed oil content, to the increase of the weight of 1000 seeds and to the decrease of content of the shell. Two-line SC hybrid was created by crossing the cytoplasmatic male sterile line of the mother with a father line with fertility restoration genes. Borneo is a high protein confectionary type hybrid that has been registered in Slovakia (EU in 2009. It contains successfully combined genes responsible for high genetic potential for yield and valuable technical and technological seed traits. The hybrid is adequate for nutrition, dehuling and kernel production. Borneo is a medium early hybrid with the genetic potential for yield of over 4,5t/ha and its seed oil content is under 43%. .
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Covy D. Jones; Mikel R. Stevens; Von D. Jolley; Bryan G. Hopkins; Scott L. Jensen; Dave Turner; Jason M. Stettler
2016-01-01
Seeds of most Great Basin lupine (Lupinus spp. [Fabaceae]) species are physically dormant and thus, difficult to establish in uniform stands in seed production fields. We designed this study to examine 5 seed scarification techniques, each with 11 levels of application (including a non-scarified control), to reduce the physical seed dormancy of longspur lupine...
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Daddino, Michelle
2010-01-01
In this article, the author describes an art project wherein kindergarten students painted sunflowers. These beautiful and colorful sunflowers were inspired by the book "Camille and the Sunflowers" by Laurence Anholt, which does an amazing job of introducing young children to the art and life of Vincent van Gogh.
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Biplot Analysis of Silicon Dioxide on Early Growth of Sunflower
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Sabaghnia Naser
2016-06-01
Full Text Available Research into nanotechnology has advanced in almost all fields of technology and the aim of this study was to evaluate the role of nano-silicon dioxide (nano-SiO2 in germination performance sunflower. Germination and seedling growth are the most important stage of plant development and are critical factors to crop production and are essential to achieve optimum performance. The effects of pre-germination hydration in solutions of nano-SiO2 (0, 0.2, 0.4, 0.6, 0.8, 1 and 1.2 mM for 8 h on germination characteristics of sunflower were investigated. The trait by treatment (TT biplot explained 93% of the total variation of the standardized data (77% and 16% for the first and second principal components, respectively. According to polygon-view of TT biplot, T2 (0.2 mM had the highest values for all of the measured traits except mean germination time and the time to 50% germination. The germination percentage was determined as the best trait and showed the high association with promptness index, energy of germination and germination rate traits. The results of the present study indicated that pre-sowing seed treatments with low concentration of nano-SiO2 had favorable effect sunflower seed germination and seedling early growth. Such a similar outcome could be applied in the future to outline other crops in response to nano-particles as well as to help define tolerance tools for recommendations in stressful conditions in the world.
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Energy Technology Data Exchange (ETDEWEB)
Bastianoni, Simone; Coppola, Fazio; Tiezzi, Enzo [Department of Chemical and Biosystems Sciences, Siena University, via della Diana, 2A, 53100 Siena (Italy); Colacevich, Andrea; Borghini, Francesca; Focardi, Silvano [Department of Environmental Sciences, Siena University, via Mattioli 4, 53100 Siena (Italy)
2008-07-15
The diversification of different types and sources of biofuels has become an important energy issue in recent times. The aim of this work is to evaluate the use of two kinds of renewable feedstocks in order to produce biodiesel. We have analyzed the potential production of oil from two species of macroalgae considered as waste coming out from a lagoon system involved in eutrophication and from sunflower seeds. We have tested oil extraction yields of both feedstock. Furthermore, a comparison has been carried out based on the emergy approach, in order to evaluate the sustainability and environmental performance of both processes. The results show that, under present conditions, considering oil extraction yields, the production of oil from sunflower seeds is feasible, because of the lower value of transformity of the final product with respect to macroalgae. On the other hand, the results demonstrate that with improvements of oil extraction methodology, macroalgae could be considered a good residual biomass usable for biofuel production. (author)
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International Nuclear Information System (INIS)
Abdel-Gawad, H.; Khatab, M.S.; Hegazi, B.
2007-01-01
Ethyl -1- 14 C-chlorpyrifos and some of its degradation products have been prepared for the present investigation. Sunflower plants were treated with 14 C-chlorpyrifos under conditions simulating local agricultural practice. 14 C-residue in seeds were determined at different time intervals. At harvest time about 8 % of 14 C-activity was associated with oil. The methanol soluble 14 C-residues accounted for 0.8 % of the total seed residues, while the cake contained about 80 % of the total residues. About 46 % of the 14 C-activity in the crude oil could be eliminated by simulated commercial processes locally used for oil refining. The refined oil had a 14 C- residue level of about 21 ppm. Chromatographic analysis of crude and refined oil revealed the presence of the parent compound together with three metabolites which were identified as chlorpyrifos oxon, desethyl chlorpyrifos, and desethyl chlorpyrifos oxon in addition to an unknown compound. Methanol extract of the cake revealed the presence of the parent compound and its oxon as free compounds. Acid hydrolysis of the conjugated metabolites in the methanol extract yielded desethyl chlorpyrifos and 3, 5, 6- trichloro-2-hydroxypyridine
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FORTIFICATION OF SUNFLOWER PLANTS (HELIANTHUS ANNUUS FORTIFICATION OF SUNFL
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Petr Škarpa
2013-02-01
Full Text Available Selenium is a trace element which in small amounts is necessary for human and animal nutrition. In the organism it helps a number of antioxidant enzymes to function normally. In many parts of the world, including the Central European region, its content in agricultural products is very low. Attempts are therefore made to increase its content and cover human requirements with biologically valuable products by incorporating selenium into the system of plant nutrition. In a vegetation trial established in 2010 and 2011 we explored the effect of foliar applications of Se (IV on achenes yields and on content of selenium in the seeds and the uptake of selenium by the sunflower stand. Solutions of sodium selenite at 0.16 and 0.5 g Se.he-1 were applied at rates 50 and 150 g Se.ha-1 at the beginning of elongation growth (stage R-1. Sunflower achenes yields were significantly influenced by the weather in the experimental years. In 2011 sunflower production was by 29.4% lower than in 2010. Se fortification in dose 50 g Se.ha-1 increased sunflower achenes yield by 3.1%. The higher dose of selenium (150 g Se.ha-1 reduced yields by 6.8% compared with the no-fertilized treatment. Due to the effect of foliar Se nutrition the content of selenium in sunflower achenes increased highly significantly from 123 µg.kg-1 to 6,004 µg.kg-1 of achenes. The weight of 1000 achenes, oil content and content of palmitic, palmitoleic, oleic, linoleic acids were not significantly affected by selenium application. Fortification of Se increased stearic acid content from 3.16% to 3.47%.
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The effects of different warm stratification periods on the seed ...
African Journals Online (AJOL)
PRECIOUS
2009-09-11
Sep 11, 2009 ... the climate chamber for 10, 11 and 12 weeks, seeds were transferred in plastic bags including pumice medium and left at 5°C. After complete dormancy, seeds were transferred to climate room at 22°C for germination. Statistical analysis. The data were analyzed using two-way (factorial) ANOVA. Signifi-.
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Response of stored potato seed tubers from contrasting cultivars to accumulated day-degrees
Struik, P.C.; Putten, van der P.E.L.; Caldiz, D.O.; Scholte, K.
2006-01-01
In potato (Solanum tuberosum L.), the accumulated day-degrees (temperature sum, calculated by accumulating the daily temperatures) from dormancy break until seed tuber use has been suggested as an indicator of the physiological status of the seed. We tested whether similar temperature sums differing
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Directory of Open Access Journals (Sweden)
Janete Motta da Silva Gonzaga
2012-08-01
Full Text Available Pre-germination treatments such as scarification and the use of growth regulators can provide the dormancy breaking in seeds and enhance the emergence and development of seedlings. The aim of this study was to determine appropriate treatments to overcome seed dormancy and enhance the initial growth of seedlings of Spondias tuberosa. We used a randomized design in factorial 2 x 4, with the following factors: seeds scarified or not scarified and then soaked in water or aqueous solutions of gibberellin, cytokinin and ethylene, with 4 replicates and 15 seeds. There was no significant interaction between scarification treatments and use of growth regulators. Mechanical scarification and soaking seeds in solutions containing umbuzeiro growth regulators does not increase the percentage of seedling emergence, however soaking in a solution of Ethrel at 100 ppm provides higher speed of emergence and root development. Tratamentos pré-germinativos, como a escarificação e o uso de reguladores de crescimento, podem proporcionar a superação de dormência em sementes e incrementar a emergência e o desenvolvimento de plântulas. O objetivo da presente pesquisa foi determinar tratamentos adequados para a superação da dormência de sementes e potencialização do crescimento inicial de plântulas de umbuzeiro. Utilizou-se o delineamento inteiramente casualizado, em fatorial 2 x 4, sendo os fatores: sementes escarificadas ou não escarificadas e, posteriormente, imersas em água ou soluções aquosas de giberelina, citocinina ou etileno, com 4 repetições de 15 sementes. Não houve interação significativa entre os tratamentos escarificação e uso de reguladores de crescimento. A escarificação mecânica e a embebição de sementes de umbuzeiro em soluções contendo reguladores de crescimento não aumenta a percentagem de emergência de plântulas, entretanto a embebição em solução de Ethrel a 100 ppm proporciona maior velocidade de emergência e
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Different purification methods and quality of sunflower biodiesel
Energy Technology Data Exchange (ETDEWEB)
Pighinelli, A.L.M.T.; Park, K.J. [Campinas State Univ., Sao Paulo (Brazil). School of Agricultural Engineering; Ferrari, R.A.; Miguel, A.M.R.O. [Food Technology Inst., Sao Paulo (Brazil)
2010-07-01
Biodiesel is derived from triacylglycerides and is produced primarily through transesterification, a chemical reaction of vegetable oils with alcohol, methanol or ethanol. The cost of raw material should be considered since 85 per cent of production cost is related to vegetable oil. The purpose of this study was to evaluate oil expression of sunflower seed. It also examined the sunflower crude oil as a raw material for biodiesel by transesterification in both laboratory and pilot scale studies. Three different biodiesel purification methods were examined. The best result for oil expelling (68.4 per cent) at the experimental stage was obtained for seeds with a moisture content of 6.9 per cent at 25 degrees C and at a screw speed of 114 rpm. For biodiesel production at the laboratory scale, the best result for oil expelling was 87.5 per cent. It was obtained with an ethanol:oil molar ratio of 4.7:1 and with a 4.42 per cent catalyst concentration related to the quantity of oil that had to be transesterified. The experimental condition was applied at a bigger scale with a batch stirred tank reactor. For purification with washing, the biodiesel yield was 84.2 per cent. Purification with silica resulted in a yield of 84.6 per cent. A better quality biofuel was obtained through distillation of biodiesel.
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Alleviate Seed Ageing Effects in Silybum marianum by Application of Hormone Seed Priming
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Seyed Ata SIADAT
2015-09-01
Full Text Available Most of the medicinal plants have seed dormancy or poor seed germination. This is due to their natural compounds or their morphological structure. Existence of such mechanisms makes the seeds able to endure harsh environments, stressful conditions or natural ageing. Different seed enhancement treatments were proposed in order to improve seed germination. In this study, it was examined Silybum marianum seed longevity (0, 48 and 72 hour of ageing and the response to seed priming when using different concentrations of cytokinin (50, 200, 350 and 500 ppm and different duration of treatment (8, 12 and 24 hour. Results revealed that ageing could be successfully alleviated using seed priming. Seed ageing significantly affected seed germination and vigour. Application of cytokinin considerably improved seed vigour in aged and non aged seeds. The most effective seed priming treatment was with 500 ppm cytokine, with the duration of 24 hours. In conclusion, it can be recommend the used of plant growth regulators like cytokine, as a good priming agent, to recover losses of seed quality and improve germination characteristics.
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Growth regulator induced mobilization of 14C-metabolites into sunflower heads
International Nuclear Information System (INIS)
Prasad, T.G.; Udaykumar, M.; Rama Rao, S.; Krishna Sastry, K.S.
1977-01-01
Effect of exogenous application of mixtures of NAA, Ga and BA to the head in sunflower, after pollination and fertilization, on the mobilization of 14 C-metabolites was studied. Application of such mixtures increased mobilization and altered the pattern of translocation. TIBA applied to the head when the ray florets only had commenced opening also caused an increase in mobilization of 14 C-metabolites. Percent activity in relation to the activity fixed by the leaf increased from 36.8 in control to 63 in TIBA treated head. Field experiments conducted for 2 seasons also confirmed effectiveness of TIBA application in increasing percent seed filling and also 1000 grain weight. In sunflower it was possible to increase the sink capacity by application of growth regulators. (author)
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Directory of Open Access Journals (Sweden)
Michael D. Hare
2018-01-01
Full Text Available The germination performances of fresh seed lots were determined for 5 tropical forage species: Mulato II hybrid brachiaria [Urochloa ruziziensis (syn. Brachiaria ruziziensis x U. decumbens (syn. B. decumbens x U. brizantha (syn. B. brizantha], Mombasa guinea [Megathyrsus maximus (syn. Panicum maximum], Tanzania guinea [M. maximus (syn. P. maximum], Ubon paspalum (Paspalum atratum and Ubon stylo (Stylosanthes guianensis, stored under ambient conditions in Thailand (mean monthly temperatures 23‒34 ºC; mean monthly relative humidity 40‒92% or in a cool room (18‒20 ºC and 50% relative humidity for up to 6 years. The first paper of this study showed all seeds, except unscarified Ubon stylo seed, were dead after a single year of storage in ambient conditions. This second paper shows that cool-room storage extended seed viability, but performance varied considerably between species. Germination percentage under laboratory conditions declined to below 50%, after 3 years storage for Mombasa guinea seed and Tanzania guinea seed, 4 years for Ubon paspalum seed and 4‒5 years for Mulato II seed. Ubon stylo seed maintained high germination for 5 years, in both cool-room storage (96% and ambient-room storage (84%. Apparent embryo dormancy in acid-scarified Mulato II seed steadily increased with time in cool-storage and this seed had to be acid-scarified again each year at the time of germination testing to overcome dormancy. Physical dormancy of Mulato II seeds, imposed by the tightly bound lemma and palea in unscarified seed, was not overcome by length of time in cool-storage and these seeds had to be acid-scarified to induce germination. Hardseeded percentage in Ubon stylo seed remained high throughout the study and could be overcome only by acid-scarification. The difficulties of maintaining acceptable seed germination percentages when storing forage seeds in the humid tropics are discussed.
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Boriollo, Marcelo Fabiano Gomes; Souza, Luiz Silva; Resende, Marielly Reis; Silva, Thaísla Andrielle da; Oliveira, Nelma de Mello Silva; Resck, Maria Cristina Costa; Dias, Carlos Tadeu dos Santos; Fiorini, João Evangelista
2014-04-02
This research evaluated the genotoxicity of oil and tincture of H. annuus L. seeds using the micronucleus assay in bone marrow of mice. The interaction between these preparations and the genotoxic effects of doxorubicin (DXR) was also analysed (antigenotoxicity test). Experimental groups were evaluated at 24-48 h post treatment with N-Nitroso-N-ethylurea (positive control - NEU), DXR (chemotherapeutic), NaCl (negative control), a sunflower tincture (THALS) and two sources of sunflower oils (POHALS and FOHALS). Antigenotoxic assays were carried out using the sunflower tincture and oils separately and in combination with NUE or DXR. For THALS, analysis of the MNPCEs showed no significant differences between treatment doses (250-2,000 mg.Kg-1) and NaCl. A significant reduction in MNPCE was observed when THALS (2,000 mg.Kg-1) was administered in combination with DXR (5 mg.Kg-1). For POHALS or FOHALS, analysis of the MNPCEs also showed no significant differences between treatment doses (250-2,000 mg.Kg-1) and NaCl. However, the combination DXR + POHALS (2,000 mg.Kg-1) or DXR + FOHALS (2,000 mg.Kg-1) not contributed to the MNPCEs reduction. This research suggests absence of genotoxicity of THALS, dose-, time- and sex-independent, and its combination with DXR can reduce the genotoxic effects of DXR. POHALS and FOHALS also showed absence of genotoxicity, but their association with DXR showed no antigenotoxic effects.
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Kolbas, A; Mench, M; Herzig, R; Nehnevajova, E; Bes, C M
2011-01-01
Use of sunflower (Helianthus annuus L.) for Cu phytoextraction and oilseed production on Cu-contaminated topsoils was investigated in afield trial at a former wood preservation site. Six commercial cultivars and two mutant lines were cultivated in plots with and without the addition of compost (5% w/w) and dolomitic limestone (0.2% w/w). Total soil Cu ranged from 163 to 1170 mg kg(-1). In soil solutions, Cu concentration varied between 0.16-0.93 mg L(-1). The amendment increased soil pH, reduced Cu exposure and promoted sunflower growth. Stem length, shoot and capitulum biomasses, seed yield, and shoot and leaf Cu concentrations were measured. At low total soil Cu, shoot Cu mineralomass was higher in commercial cultivars, Le., Salut, Energic, and Countri, whereas competition and shading affected morphological traits of mutants. Based on shoot yield (7 Mg DW ha(-1)) and Cu concentration, the highest removal was 59 g Cu ha(-1). At high total soil Cu, shoot Cu mineralomass peaked for mutants (e.g., 52 g Cu ha(-1) for Mutant 1 line) and cultivars Energic and Countri. Energic seed yield (3.9 Mg air-DW ha(-1)) would be sufficient to produce oil Phenotype traits and shoot Cu removal depended on sunflower types and Cu exposure.
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Manoorkar V B; Mandge S V; B D Gachande
2015-01-01
In present study, aqueous and ethanol extracts of leaf & latex of Calotropis procera (Ait.) was tested for their antifungal activity against dominant storage seed-borne fungi of some oil seeds such as groundnut, soybean, sunflower and mustard. The antifungal effect of ethanol and aqueous extracts of leaf & latex of Calotropis procera (Ait.) against ten seed-borne dominant fungi viz., Cuvularia lunata, Alternaria alternata, Rhizoctonia solani, Fusarium solani, Penicillium chrysogenum, Asperg...
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Cabello, Julieta V; Giacomelli, Jorge I; Piattoni, Claudia V; Iglesias, Alberto A; Chan, Raquel L
2016-03-20
HaHB11 is a member of the sunflower homeodomain-leucine zipper I subfamily of transcription factors. The analysis of a sunflower microarray hybridized with RNA from HaHB11-transformed leaf-disks indicated the regulation of many genes encoding enzymes from glycolisis and fermentative pathways. A 1300bp promoter sequence, fused to the GUS reporter gene, was used to transform Arabidopsis plants showing an induction of expression after flooding treatments, concurrently with HaHB11 regulation by submergence in sunflower. Arabidopsis transgenic plants expressing HaHB11 under the control of the CaMV 35S promoter and its own promoter were obtained and these plants exhibited significant increases in rosette and stem biomass. All the lines produced more seeds than controls and particularly, those of high expression level doubled seeds yield. Transgenic plants also showed tolerance to flooding stress, both to submergence and waterlogging. Carbohydrates contents were higher in the transgenics compared to wild type and decreased less after submergence treatments. Finally, transcript levels of selected genes involved in glycolisis and fermentative pathways as well as the corresponding enzymatic activities were assessed both, in sunflower and transgenic Arabidopsis plants, before and after submergence. Altogether, the present work leads us to propose HaHB11 as a biotechnological tool to improve crops yield, biomass and flooding tolerance. Copyright © 2016 Elsevier B.V. All rights reserved.
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Directory of Open Access Journals (Sweden)
S. Zafarian
2013-06-01
Full Text Available Karafs Kouhi (Kelussia odoratissima M. is one of the important medicinal plants of umbelliferae family and native of Zagros Mountains range, which is endangered due to illegal harvests. In order to accelerate breaking the seed dormancy of this plant, a factorial experiment based on completely randomized design with four replications, was carried in Faculty of Agriculture, Shahrekord University. The seeds of Karafs Kouhi from Saraghaseyed ecotype were treated under three time periods (25, 50, 75 and 100 days after planting, combination of enzylaminopurine (BAP (concentrations of 0, 0.75 and 1.5 mg/L and gibberellic acid (GA3 (concentrations of 0, 250 and 500 mg/L and application methods of these growth regulators (soaking seeds in the growth regulators and use of growth regulators directly on the medium. In this experiment, germination percentage, rootlet length and hypocotyl length were studied. The results indicated that 100 days after planting significantly (P≥0.01 showed the highest rates in the three studied traits. In this treatment, the germination percentage was 86.94%, rootlet length was 9.43 cm and hypocotyl length was 11.64 cm. Moreover, the interaction of the factors was not significant for all the traits. The best combination to increase germination percent, rootlet length and germination rate, was 0.75 mg/L BAP, 500 mg/L GA3 and direct use of growth regulators. To increase hypocotyl length, only 500 mg/L GA3 is recommended.
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New sunflower hybrids tolerant to tribenuron-methyl
Directory of Open Access Journals (Sweden)
Cvejić Sandra
2016-01-01
Full Text Available The creation of sunflower hybrids tolerant to tribenuron-methyl enabled the use of wider palette of herbicides to control effectively weeds during the growing season. Moreover, thanks to this tolerance, chemical control of broad-leaves weeds in sunflower, especially Cirsium arvense, is more efficient. The Institute of Field and Vegetable Crops offers four new hybrids tolerant to tribenuron-methyl: NS SUMO SUN, NS SUMO STAR, NS SUMO SjAj and NS SUMO SOL, released in 2016. Hybrids belong to early and medium-early maturity groups; have high yield potential and high oil content. They are adapted for cultivation in different environmental conditions. All hybrids are resistant to broomrape (Orobanche cumana Wallr races from A-E and have a high level of tolerance to Phomopsis, white rot (Sclerotinia sclorotiorum, rust (Puccinia helianthi and others. The paper presents the results of seed and oil yield from the official trials of the Department of variety registration within the Ministry of Agriculture and Environmental Protection of the Republic of Serbia.
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Changes in sunflower breeding over the last fifty years
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Vear Felicity
2016-03-01
Full Text Available This article discusses changes in sunflower breeding objectives since the introduction of hybrid varieties 50 years ago. After a reminder of the importance of some early programmes, Canadian in particular, the present situation for each breeding objective is compared with those encountered earlier. Breeding for yield has changed from maximum possible yield under intensive agriculture to yield with resistance to abiotic stresses, moderate droughts and shallow soils in particular, helped by collaboration with agronomists to produce crop models. Breeding for oil has changed from quantity to quality and the value of seed meal is again becoming economically important. Necessary disease resistances vary with agronomic practises and selection pressure on pathogens according to varietal genetics. The possibilities of new types of sunflower are also discussed. Advances in genomics will change breeding procedures, but with rapidly changing molecular techniques, international collaboration is particularly important.
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Detection Characteristics of Gamma-Irradiated Seeds by using PSL, TL, ESR and GC/MS
International Nuclear Information System (INIS)
Kim, K.H.; Shon, J.H.; Kang, Y.J.; Jo, T.Y.; Park, H.Y.; Kwak, J.Y.; Lee, J.H.; Park, Y.C.; Kim, J.I.; Lee, H.J.; Lee, S.J.; Han, S.B.
2013-01-01
In this study, we investigated the applicability of the photostimulated luminescence (PSL), thermoluminescence (TL), electron spin resonance (ESR) and gas chromatography/mass spectrometry (GC/MS) methods for 5 seeds which are not allowed to be irradiated in Korea. All 5 seeds including evening primrose seed, safflower seed, rape seed, sunflower seed and flax seed were analyzed. Samples were irradiated at 1~10 kGy using a 60 Co gamma-ray irradiator. In PSL study, the photon counts of all the unirradiated samples showed negative (lower than 700). The photon counts of irradiated (1, 5, 10 kGy) samples showed positive (higher than 5,000). In TL analysis, results showed that it is possible to apply TL method to all foods containing minerals. In ESR measurements, the ESR signal (single-line) intensity of irradiated foods was higher than non-irradiated foods. The hydrocarbons 1,7-hexadecadiene (C 16:2 ) and 8-heptadecene (C 17:1 ) from oleic acid were detected only in the irradiated samples before and after the treatment at doses ≥ 1 kGy, but they were not detected in non-irradiated samples before and after treatment. These two hydrocarbons could be used as markers to identify irradiated safflower seed, rape seed, Sunflower seed and flax seed. And then, the hydrocarbons 1,7,10-hexadecatriene (C 16:3 ) and 6,9-heptadecadiene (C 17:2 ) from linoleic acid were detected in the evening primrose seed, safflower seed and sunflower seed. According to the results, PSL, TL and GC/ MS methods were successfully applied to detect the irradiated foods. It is concluded that PSL, TL and GC/MS methods are suitable for detection of irradiated samples and a combined method is recommendable for enhancing the reliability of detection results. (author)
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Density Distribution Sunflower Plots
Directory of Open Access Journals (Sweden)
William D. Dupont
2003-01-01
Full Text Available Density distribution sunflower plots are used to display high-density bivariate data. They are useful for data where a conventional scatter plot is difficult to read due to overstriking of the plot symbol. The x-y plane is subdivided into a lattice of regular hexagonal bins of width w specified by the user. The user also specifies the values of l, d, and k that affect the plot as follows. Individual observations are plotted when there are less than l observations per bin as in a conventional scatter plot. Each bin with from l to d observations contains a light sunflower. Other bins contain a dark sunflower. In a light sunflower each petal represents one observation. In a dark sunflower, each petal represents k observations. (A dark sunflower with p petals represents between /2-pk k and /2+pk k observations. The user can control the sizes and colors of the sunflowers. By selecting appropriate colors and sizes for the light and dark sunflowers, plots can be obtained that give both the overall sense of the data density distribution as well as the number of data points in any given region. The use of this graphic is illustrated with data from the Framingham Heart Study. A documented Stata program, called sunflower, is available to draw these graphs. It can be downloaded from the Statistical Software Components archive at http://ideas.repec.org/c/boc/bocode/s430201.html . (Journal of Statistical Software 2003; 8 (3: 1-5. Posted at http://www.jstatsoft.org/index.php?vol=8 .
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Directory of Open Access Journals (Sweden)
H. Nazarly
2016-05-01
Full Text Available In order to study the qualitative and quantitative yield and some agronomic characteristics of sunflower (Helianthus annus L. in response to seed inoculation with PGPR under various levels of nitrogen fertilizer, a factorial experiment was conducted based on a randomized complete block design with three replications in field experimental University of Mohaghegh Ardabili during growing season of 2009-2010. Factors were nitrogen fertilizer in three levels (0, 80 and 160 kg N ha-1 as urea and seed inoculation with plant growth promoting rhizobacteria in four levels containing, without inoculation (as control, seed inoculation with Azotobacter chroococcum strain 5, Azospirillum lipoferum strain OF, Psedomunas strain 186. Results indicated that nitrogen levels and seed inoculation with Plant Growth Promoting Rhizobacteria (PGPR had significant effects on all of characteristics studied (except grain 1000 weight and stem diameter. Grain yield, plant height, head diameter, seed number per head, , yield and oil percentage, yield and protein percentage increased with increasing of nitrogen fertilizer and application of seed inoculation with PGPR. Response of grain yield wasn't the same for various levels of nitrogen fertilizer and seed inoculation with PGPR. The highest grain yield belonged to application of 160 kg N ha-1 and seed inoculation with Azotobacter. Means comparison showed that treatment compounds N160 × without inoculation with PGPR and N80 × seed inoculation with PGPR Azotobacter had similar grain yields. Thus, it can be suggested that in order to increasing of grain yield seed should be inoculated with Azotobacter bacteria × 80 kg N/ha in conditions of Ardabil region.
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Directory of Open Access Journals (Sweden)
Banys M
2012-12-01
Full Text Available Malgorzata Banys,1,2 Andreas D Hartkopf,1 Natalia Krawczyk,1 Tatjana Kaiser,1 Franziska Meier-Stiegen,1 Tanja Fehm,1 Hans Neubauer11Department of Obstetrics and Gynecology, University of Tuebingen, Tuebingen, Germany; 2Department of Obstetrics and Gynecology, Marienkrankenhaus Hamburg, Hamburg, GermanyAbstract: Tumor dormancy describes a prolonged quiescent state in which tumor cells are present, but disease progression is not yet clinically apparent. Breast cancer is especially known for long asymptomatic periods, up to 25 years, with no evidence of the disease, followed by a relapse. Factors that determine the cell's decision to enter a dormant state and that control its duration remain unclear. In recent years, considerable progress has been made in understanding how tumor cells circulating in the blood interact and extravasate into secondary sites and which factors might determine whether these cells survive, remain dormant, or become macrometastases. The mechanisms of tumor cell dormancy are still not clear. Two different hypotheses are currently discussed: tumor cells persist either by completely withdrawing from the cell cycle or by continuing to proliferate at a slow rate that is counterbalanced by cell death. Because dormant disseminated tumor cells may be the founders of metastasis, one hypothesis is that dormant tumor cells, or at least a fraction of them, share stem cell-like characteristics that may be responsible for their long half-lives and their suggested resistance to standard chemotherapy. Therefore, knowledge of the biology of tumor cell dormancy may be the basis from which to develop innovative targeted therapies to control or eliminate this tumor cell fraction. In this review, we discuss biological mechanisms and clinical implications of tumor dormancy in breast cancer patients.Keywords: tumor dormancy, disseminated tumor cell, circulating tumor cell, targeted therapy
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Chen, Shun-Ying; Chou, Shih-Han; Tsai, Ching-Chu; Hsu, Wen-Yu; Baskin, Carol C; Baskin, Jerry M; Chien, Ching-Te; Kuo-Huang, Ling-Long
2015-09-01
Breaking of seed dormancy by moist cold stratification involves complex interactions in cells. To assess the effect of moist cold stratification on dormancy break in seeds of Acer morrisonense, we monitored percentages and rates of germination and changes in plant growth regulators, sugars, amino acids and embryo ultrastructure after various periods of cold stratification. Fresh seeds incubated at 25/15 °C for 24 weeks germinated to 61%, while those cold stratified at 5 °C for 12 weeks germinated to 87% in 1 week. Neither exogenous GA3 nor GA4 pretreatment significantly increased final seed germination percentage. Total ABA content of seeds cold stratified for 12 weeks was reduced about 3.3-fold, to a concentration similar to that in germinated seeds (radicle emergence). Endogenous GA3 and GA7 were detected in 8-week and 12-week cold stratified seeds but not in fresh seeds. Numerous protein and lipid bodies were present in the plumule, first true leaves and cotyledons of fresh seeds. Protein and lipid bodies decreased greatly during cold stratification, and concentrations of total soluble sugars and amino acids increased. The major non-polar sugars in fresh seeds were sucrose and fructose, but sucrose increased and fructose decreased significantly during cold stratification. The major free amino acids were proline and tryptophan in fresh seeds, and proline increased and tryptophan decreased during cold stratification. Thus, as dormancy break occurs during cold stratification seeds of A. morrisonense undergo changes in plant growth regulators, proteins, lipids, sugars, amino acids and cell ultrastructure. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
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Optimal treatment increased the seed germination of Salvia verticillata L.
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ALALEH KHAKPOOR
2015-12-01
Full Text Available Most seeds of the medicinal species are variable regarding their ecological compatibility with environmental conditions. Therefore, identifying the ecophysiological factors that affect dormancy and create optimal conditions for seed germination of medicinal plants is necessary for their culture and production. To evaluate the effect of different treatments on seed germination of medicinal species of Salvia verticillata, collected in the summer of 2010 in Eastern Azarbaijan, we have performed completely randomized experimental tests with 4 replications. The experimental design of treatment prior to growth included: scrape the skin with sandpaper, treatment with 500 ppm gibberellic acid for 24 and 48 h, treatment with citric acid for 10, 20 and 30 minutes, chilling for 2 and 4 weeks, treatment with warm water at 70°C and control treatment. Results showed that the effect of different treatments was significant on seed germination percent of the medicinal plant Salvia verticillata. Scrape the skin with sandpaper, citric acid treatment for 10, 20 and 30 minutes, and gibberellic acid treatment for 24 hours, increased the germination percentage compared to the control treatment. The most positive impact was observed on the dormancy breaking and germination of medicinal species Salvia verticillata.
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Effects of diets containing hemp seeds or hemp cake on fatty acid ...
African Journals Online (AJOL)
Esnart Mukumbo
2018-02-23
Feb 23, 2018 ... Council Directive, 2003) for fibre and oil production. ... fractions of hemp seed, soybean and sunflower seed have been determined at 19.7%, 7.8% and 0.5% .... (FAMES) were quantified by gas chromatography using a Varian ...
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Cell lineage patterns in the shoot meristem of the sunflower embryo in the dry seed
International Nuclear Information System (INIS)
Jegla, D.E.; Sussex, I.M.
1989-01-01
We mapped the fate of cells in the shoot meristem of the dry-seed embryo of sunflower, Helianthus annuus L. cv. Peredovic, using irradiation-induced somatic sectors. We analyzed 249 chlorophyll-deficient or glabrous (hairless) sectors generated in 236 plants. Most sectors observed in the inflorescence extended into vegetative nodes. Thus cell lineages that ultimately gave rise to reproductive structures also contributed to vegetative structures. No single sector extended the entire length of the shoot. Thus the shoot is not derived from one or a few apical initials. Rather, the position, vertical extent, and width of the sectors at different levels of the shoot suggest that the shoot is derived from three to four circumferential populations of cells in each of three cell layers of the embryo meristem. Sectors had no common boundaries even in plants with two or three independent sectors, but varied in extent and overlapped along the length of the shoot. Thus individual cells in a single circumferential population behaved independently to contribute lineages of different vertical extents to the growing shoot. The predicted number of circumferential populations of cells as well as the apparent cell number in each population was consistent with the actual number of cells in the embryo meristem observed in histological sections
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Directory of Open Access Journals (Sweden)
Eman Rahamtalla Ahmed Elsheikh
2015-12-01
Full Text Available Two field experiments with Sunflower on deep cracking soil with heavy clay (vertisol were conducted at Gezira Research Station Farm during two executive winter seasons, in WadMedani, Sudan. The crop was sown in the third week of November and in the first week of December for seasons 2012 and 2013 respectively. The experimental design was split plot design with three replicates. The Sunflower hybrid tested in the study was Hysun 33. The objective of this study was to determine the effect of three different irrigation intervals of 10, 15 and 20 days and two intra-row plant spacings of 30 cm and 40 cm on yield and yield components of Sunflower. The seed yields obtained from the different treatments were in the ranges of 1890-3300 kg/ha and 1590-3290 kg/ha for the first and second season respectively. The corresponding computed on average crop water productivity was in the range of 0.31-0.43 kg/m3. The study clearly indicated that the highest seed yield was obtained when the crop was sown at 40 cm plant spacing and irrigated every 10 days. The highest crop water productivity was achieved from irrigation every15 days in both planting spacings
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Directory of Open Access Journals (Sweden)
Vasić Dragana M.
2002-01-01
Full Text Available Five populations of each H. molis, H. maximiliani, H. rigidus and H. tuberosus were screened for resistance to stem form of Sclerotinia. On the basis of the results obtained by screening, nine crosses of resistant populations with either other wild species populations or with cultivated sunflower were made. As in some crosses a small quantity of seed was produced and the seeds germinated poorly, modified tissue culture methods were used to enhance germination and produce clones of interesting plants. These methods were found to be efficient both for seed germination and plant production and multiplication.
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Directory of Open Access Journals (Sweden)
Kai Zhao
2018-02-01
Full Text Available Dormancy Associated MADS-box genes are SVP/MADs-box members and supposed to play crucial roles in plant dormancy of perennial species. In Prunus mume, PmDAM6 has been previously identified to induce plant dormancy. In the current study, six PmDAMs were cloned in P. mume and functionally analyzed in yeast and tobacco to detect the roles of the genes paralogous to PmDAM6. The expression patterns together with sequence similarities indicate that PmDAMs are divided into two sub-clades within SVP group. Moreover, PmDAMs are verified to take part in the development of different plant organs, specifically the flower buds, in some intricate patterns. Furthermore, the PmDAM proteins are found to have special functions by forming corresponding protein complex during the development of flower bud and induction of dormancy. In particular, when PmDAM1 dominating in flower bud in the warm months, the protein complexes are consisted of PmDAM1 itself or with PmDAM2. With the decrease temperatures in the following months, PmDAM6 was found to be highly expressed and gradually changed the complex structure to PmDAM6-protein complex due to strong binding tendencies with PmDAM1 and PmDAM3. Finally, the homodimers of PmDAM6 prevailed to induce the dormancy. The results obtained in the current study highlight the functions of PmDAMs in the tissue development and dormancy, which provide available suggestions for further explorations of protein-complex functions in association with bud growth and dormancy.
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Characterization of enzymatically extracted sunflower seed oil as well as the protein residues
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Sitohy, M. Z.
1993-12-01
Full Text Available Sunflower seed oil was enzymatically extracted with six different enzymes: cellulase, hemicellulase, animal proteinase, acid proteinase, pectinase and pectinex under the following conditions: substrate concentration in phosphate buffer (0.5M, pH 5 30%, enzyme concentration 2% (E/S, temperature 50°C and time 3 hours. The obtained oils were analyzed for physicochemical properties and fatty acid profiles. The protein residues were analyzed for amino acid compositions. The results showed that the enzymatic extraction with cellulase or hemicellulase could maintain good oil quality of the extracted oils as their levels of linoleic and oleic acids recorded similar values to those of the control oil extracted with organic solvents. Also the level of iodine value was in the same level of control. On the other hand, the use of proteases in the enzymatic extraction of sunflower seed oil caused some reductions in the levels of the unsaturated fatty acids as well as the iodine value. The pectinases showed a similar trend to that of the proteinase with the least recovery of linoleic acid among the different oils under study. Similarly, the use of cellulases did not change the amino acid composition of the protein residue as compared to the control, in the contrary to the extraction with the proteinases which caused reduction of some amino acids from the protein residues especially lysine, leucine, iso-leucine, alanine, arginine and aspartic. In that respect the use of pectinases behaved similar to cellulases.
Aceite de semilla de girasol fue extraído enzimáticamente con seis enzimas diferentes: celulasa, hemicelulasa, proteinasa animal, proteinase acida, pectinasa y pectinex bajo las condiciones siguientes: concentración de sustrato en tampón fosfato (0,5M, pH 5 30%, concentración enzimática 2% (E/S, temperatura 50°C y tiempo 3 horas. Los aceites obtenidos fueron analizados por sus propiedades fisicoquímicas y perfiles de ácidos grasos -
Effect of X-rays on germination of some wild papilionaceous seeds
International Nuclear Information System (INIS)
Chaghtai, S.A.; Khan, S.S.; Sultan, Suman
1978-01-01
Dry seeds of Aeschynomene indica Linn., Alysicarpus rugosus, Desmodium gangeticum (Linn.) DC., three species of Indigofera Tephrosia purpurea (Linn.) Pers. and Zorniagibbosa were irradiated with 1500r dose of X-rays for breaking their dormancy. Whereas none of the seeds of Alysicarpus rugosus, Indigo fera enneaphylla, I.linifolia and Zornia gibbosa could germinate. 23%, 10%, 3% and 2% germination was recorded for the seeds of Indigofera hirsuta sansu Baker, Tephrosia purpurea Aeschynomene indica and Desmodium gangeticum respectively. (author)
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Directory of Open Access Journals (Sweden)
Paulo Sérgio Nascimento Lopes
2009-09-01
difficulty of obtaining seedlings mainly depending on the dormancy of its seeds. Thus, the purpose of this study was to evaluate the seeds overcoming dormancy methods of Spondias Tuberosa to promote an increase in the rates of germination, uniformity and vigor of the seedlings. Two experiments were independently conducted. The treatments of the first experiments were: test, immersion of the seeds in water for 24 hours, immersion of the seeds in solution of gibberellic acid 1000 mg / L for 24 hours, scarification of seeds with sulfuric acid PA for 10 minutes and mechanical scarification of seeds. In the second experiment, the treatments consisted of planting the seeds with 0, 30, 60, 90, 120, 150, 180 and 210 days of storage in paper bags under laboratory conditions, at an average temperature of 22.5° C and relative humidity of 65%. In the first study it was found that there was a significant effect of the methods to seeds overcoming dormancy, concluding that the mechanical scarification is the best treatment, with an average germination rate in 60 days after planting 26.6%. In the second experiment, storage positively influenced the germination of seeds and seedlings vigor. The best results for uniformity and germination percentage (83% were obtained between 120 and 210 days of seeds storage, while for the length and fresh weight of root, between 120 and 150 days.
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Joel, Daniel M; Chaudhuri, Swapan K; Plakhine, Dina; Ziadna, Hammam; Steffens, John C
2011-05-01
The germination of the obligate root parasites of the Orobanchaceae depends on the perception of chemical stimuli from host roots. Several compounds, collectively termed strigolactones, stimulate the germination of the various Orobanche species, but do not significantly elicit germination of Orobanche cumana, a specific parasite of sunflower. Phosphate starvation markedly decreased the stimulatory activity of sunflower root exudates toward O. cumana, and fluridone - an inhibitor of the carotenoid biosynthesis pathway - did not inhibit the production of the germination stimulant in both shoots and roots of young sunflower plants, indicating that the stimulant is not a strigolactone. We identified the natural germination stimulant from sunflower root exudates by bioassay-driven purification. Its chemical structure was elucidated as the guaianolide sesquiterpene lactone dehydrocostus lactone (DCL). Low DCL concentrations effectively stimulate the germination of O. cumana seeds but not of Phelipanche aegyptiaca (syn. Orobanche aegyptiaca). DCL and other sesquiterpene lactones were found in various plant organs, but were previously not known to be exuded to the rhizosphere where they can interact with other organisms. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Features of the rheological properties of dough with sunflower and cedar flour
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V. A. Gaysina
2016-01-01
Full Text Available Promising directions of development of assortment of flour confectionery products are currently creating new combinations, more extraordinary and interesting, the reduction in calories, increase the nutritional value, development of formulations of functional products. As enriching additives in the manufacture of pastry products can be used flour sunflower flour and cedar. Sunflower meal – one of the possible sources of increase of food value. The only raw material component of this product are sunflower seeds that have passed the purification from impurities and shell of the particles, with the subsequent removal of oil from them and grinding. In this torment, to the maximum extent maintained all the valuable biological active substances and vitamins. Sunflower flour is a complex product: it is good recommendation system of proteins, fats, carbohydrates, including fiber, vitamins, phospholipids and mineral substances. Cedar flour is characterized by high protein content (up to 48 % is well balanced in amino acids resultant composition contains b vitamins, food fibers, micro - and macroelements, necessary for life of the human body. Cedar flour has a good functional and technological properties In this paper we study the effect of cedar flour and sunflower meal on the rheological characteristics of dough. Effect of formulation components on the rheological properties of the test is evaluated in terms of water absorption of the flour, the duration of doughing, degree of its dilution and stability when mixing. It was found that the addition of 17% sunflower meal increases the viscosity of the dough and has a strengthening effect on the structure of the dough. Adding cedar flour in the amount of 20% caused the decrease in viscosity and getting more flexible dough.
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Directory of Open Access Journals (Sweden)
Vicente de Paulo Macedo
2008-11-01
Full Text Available Avaliaram-se o desempenho e as características quali e quantitativas da carcaça de cordeiros alimentados com ração contendo semente de girassol. Utilizaram-se 16 cordeiros distribuídos aleatoriamente em um delineamento inteiramente casualizado com quatro tratamentos (0,00; 6,60; 13,20 ou 19,80% de semente de girassol na matéria natural, cada um com quatro repetições, totalizando 16 cordeiros. As dietas continham 2,65; 2,78; 2,89 e 2,93 Mcal/kg de energia metabolizável e 18,38; 18,75; 19,98 e 21,18% de proteína bruta, respectivamente, e foi fornecida ad libitum. Os cordeiros foram pesados a cada 14 dias e mantidos com as ovelhas até atingirem 28 kg, quando foram abatidos, após jejum de sólidos por 18 horas, para obtenção do peso vivo ao abate e registro do peso da carcaça quente e do conteúdo gastrintestinal, utilizados no cálculo do peso de corpo vazio. As carcaças foram mantidas por 24 horas em câmara frigorífica em temperatura de 5ºC para obtenção do peso de carcaça fria. Os níveis de semente de girassol na dieta não afetaram as características de desempenho dos cordeiros. No entanto, os pesos de carcaça quente e de carcaça fria; os pesos de pescoço, baixo, paleta, costela descoberta, costela, lombo; e os rendimentos comerciais de carcaça e costela descoberta, costela, lombo, paleta, pescoço e baixo sofreram efeito da adição da semente de girassol. O fornecimento de semente de girassol na dieta não influencia as características qualitativas e morfométricas da carcaça de cordeiros.Performance and quantitative and qualitative carcass traits of lambs fed with diets containing sunflower seed were evaluated. Sixteen lambs were randomly distributed to a completely randomized design with four diets (0.00, 6.60, 13.20 or 19.80% of sunflower seed, % as fed, with 4 replications. The diets contained 2.65, 2.78, 2.89 and 2.93 Mcal / kg of metabolize energy and 18.38, 18.75, 19.98 and 21.18% crude protein
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Genetic variance of sunflower yield components - Heliantus annuus L.
Directory of Open Access Journals (Sweden)
Hladni Nada
2003-01-01
Full Text Available The main goals of sunflower breeding in Yugoslavia and abroad are increased seed yield and oil content per unit area and increased resistance to diseases, insects and stress conditions via an optimization of plant architecture. In order to determine the mode of inheritance, gene effects and correlations of total leaf number per plant, total leaf area and plant height, six genetically divergent inbred lines of sunflower were subjected to half diallel crosses. Significant differences in mean values of all the traits were found in the F1 and F2 generations. Additive gene effects were more important in the inheritance of total leaf number per plant and plant height, while in the case of total leaf area per plant the nonadditive ones were more important looking at all the combinations in the F1 and F2 generations. The average degree of dominance (Hi/D1/2 was lower than one for total leaf number per plant and plant height, so the mode of inheritance was partial dominance, while with total leaf area the value was higher than one, indicating super dominance as the mode of inheritance. Significant positive correlation was found: between total leaf area per plant and total leaf number per plant (0.285* and plant height (0.278*. The results of the study are of importance for further sunflower breeding work.
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Energy Technology Data Exchange (ETDEWEB)
Bischoff, Tabata Zingano; Prado, Naimara Vieira do; Coelho, Silvia Renata Machado; Bischoff, Teodato Zingano [Universidade Estadual do Oeste do Parana (UNIOESTE), PR (Brazil)], emails: tabatazbi@yahoo.com.br, nai_mara@hotmail.com, srmcoelho@unioeste.br, teodato_zb@hotmail.com; Figueiredo, Paulo Roberto Abreu de [Instituto Agronomico do Parana (IAPAR), Londrina, PR (Brazil)
2011-07-01
Sunflower and crambe are viable alternatives to ethanol. Used in food production, the sunflower crop has economic, rustic and does not require specialized machinery. The crambe oil is concentrated enough, it is feasible to farm and is not edible. The extraction efficiencies of these oils gives to the heating and moisture content of grain. The aim of this study was to evaluate temperatures of oil extraction in sunflower and crambe as pies obtained. For oil extraction and acquisition of pies, we used a high pressure extruder press. The sunflower seed and crambe were extruded without heating and at temperatures of 50 and 70 deg C with three replicates for each treatment, estimated to be the pie, the amount of fat, protein and moisture. Increasing the temperature, we observed a reduction of moisture in sunflower cake, but this did not occur in seeds of crambe. For sunflower, the higher levels of lipids occurred for pie without heating, and for crambe, the higher levels of lipids occurred at 50 deg C. As for the protein, was found in both cultures, the highest level at 70 deg C. It is concluded that the extraction temperature alters the composition of oilseed cakes. (author)
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International Nuclear Information System (INIS)
Mosca, G.
1992-01-01
With the aim of assessing commercialization prospects for vegetable oils to be used as diesel fuel alternatives, this paper provides maps indicating regional production quantities for soybean, rape and sunflower seeds in Italy. It then tables and discusses the results of energy input-output analyses carried out for rape and soybean oil production
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Biodiesel from sunflower oil in supercritical methanol with calcium oxide
International Nuclear Information System (INIS)
Demirbas, Ayhan
2007-01-01
In this study, sunflower seed oil was subjected to the transesterification reaction with calcium oxide (CaO) in supercritical methanol for obtaining biodiesel. Methanol is used most frequently as the alcohol in the transesterification process. Calcium oxide (CaO) can considerably improve the transesterification reaction of sunflower seed oil in supercritical methanol. The variables affecting the methyl ester yield during the transesterification reaction, such as the catalyst content, reaction temperature and the molar ratio of soybean oil to alcohol, were investigated and compared with those of non-catalyst runs. The catalytic transesterification ability of CaO is quite weak under ambient temperature. At a temperature of 335 K, the yield of methyl ester is only about 5% in 3 h. When CaO was added from 1.0% to 3.0%, the transesterification speed increased evidently, while when the catalyst content was further enhanced to 5%, the yield of methyl ester slowly reached to a plateau. It was observed that increasing the reaction temperature had a favorable influence on the methyl ester yield. In addition, for molar ratios ranging from 1 to 41, as the higher molar ratios of methanol to oil were charged, the greater transesterification speed was obtained. When the temperature was increased to 525 K, the transesterification reaction was essentially completed within 6 min with 3 wt% CaO and 41:1 methanol/oil molar ratio
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Integrated management of sunflower necrosis disease
Shirshikar S.P.
2008-01-01
Sunflower necrosis disease (SND) is a new threat for sunflower cultivation in India. The disease was observed during 1997 in Karnataka, a major sunflower growing state of India. Later, its occurrence was reported from almost all sunflower growing states of India, posing threat to sunflower cultivation. Presently no reliable resistant sources are available. The disease being viral in nature is very much difficult to combat by single approach. At Oilseeds Research Station, Latur (M.S.), India, ...
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Czech Academy of Sciences Publication Activity Database
Lee, K. P.; Piskurewicz, U.; Turečková, Veronika; Strnad, Miroslav; Lopez-Molina, L.
2010-01-01
Roč. 107, č. 44 (2010), s. 19108-19113 ISSN 0027-8424 R&D Projects: GA ČR GA301/08/1649 Institutional research plan: CEZ:AV0Z50380511 Keywords : gibberellins * seed dormancy * DELLA Subject RIV: EF - Botanics Impact factor: 9.771, year: 2010
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International Nuclear Information System (INIS)
Abou Al Fadil, T.; Dechamp-Guillaume, G.; Poormohammad Kiani, S.; Sarrafi, A.
2004-01-01
Black stem, caused by Phoma macdonaldii, is one of the most important diseases of sunflower in many Countries. In order to study the genetic control of the disease, seeds of the inbred line AS-613 were exposed to 75 Grays of gamma rays and M1 and M2 plants were self-pollinated to obtain the M3 generation. Among M3 mutants, M3-8, a relatively resistant line to black stem, was crossed with AS-613. Seeds from this cross were grown and F1 plants were self-pollinated to produce F2 seeds from which the F3 generation was produced. Eighty-eight F3 families and two parents were used to determine the genetic variability of partial resistance to black stem in sunflower. Twelve-day-old seedlings were inoculated at the junction of the cotyledon petiole and hypocotyl with 20 micronl of pycniospore suspension. Seven days after inoculation, both cotyledon petioles of the seedling were scored according to the percentage of petiole area exhibiting symptoms (necrosis). Significant difference in resistance between the two parents, M3-8 and AS-613, indicates that mutagenesis can be considered as important tool to produce genetic variation for resistance to Phoma in sunflower. Results showed that F3 families included extreme genotypes with a relatively high resistance rate compared with the parents. Ten percent of F3 families showed a resistance rate higher than the one of the best parent, indicating transgressive segregation for resistance to black stem among families. The percentage of heritability was 69.6, which indicates that progeny selection for resistance to the disease is possible [it
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Conventional and in situ transesterification of sunflower seed oil for the production of biodiesel
Energy Technology Data Exchange (ETDEWEB)
Georgogianni, K.G.; Kontominas, M.G.; Pomonis, P.J. [Section of Industrial and Food Chemistry, Department of Chemistry, University of Ioannina 45110-Ioannina (Greece); Avlonitis, D. [Department of Petroleum Technology, TEI of Chalkida, 34600-Kavala (Greece); Gergis, V. [Department of Food Technology, TEI of Athens, 12210-Egaleo (Greece)
2008-05-15
In the present work the alkaline transesterification of sunflower seed oil with methanol and ethanol, for the production of biodiesel fuel was studied. Both conventional and in situ transesterification were investigated using low frequency ultrasonication (24 kHz) and mechanical stirring (600 rpm). Use of ultrasonication in conventional transesterification with methanol gave high yields of methyl esters (95%) after a short reaction time (20 min) similar to those using mechanical stirring. Use of ultrasonication in conventional transesterification with ethanol gave similar yields to those using mechanical stirring but significantly lower than respective yields using methanol. In the in situ transesterification the use of ultrasonication and mechanical stirring led to similar high yields (95%) of methyl esters after approximately 20 min of reaction time. In the presence of ethanol use of ultrasonication led to high ester yields (98%) in only 40 min of reaction time while use of mechanical stirring gave lower yields (88%) even after 4 h of reaction time. In situ transesterification gave similar ester yields to those obtained by conventional transesterification being an alternative, efficient and economical process. In all cases a concentration of 2.0% NaOH gave higher ester yields. Reaction rate constants were calculated, using first order reaction kinetics, to be equal to 3.1 x 10{sup -} {sup 3} s{sup -} {sup 1} for conventional transesterification using methanol and 2.0% NaOH, and 9.5 x 10{sup -} {sup 4} s{sup -} {sup 1} using ethanol. (author)
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Directory of Open Access Journals (Sweden)
M. Bolandi Amoughein
2016-02-01
Full Text Available Introduction: Studies showed that if mixed populations of annual weeds grow with the sunflower, for every 10% increase in weed biomass, seed yield would decrease by 13% (Van Gessel & Renner, 2000. In addition to control weeds using herbicides multi-stage spraying is required. In organic farming systems mulch is used to control weeds, protection, fertility and improve soil quality (Glab & Kulig, 2008; Kuchaki et al., 2001. Surface mulches from cover crops suppress weed growth by reducing light levels at the soil surface, thereby slowing photosynthesis. In return, these conditions reduce seed germination and act as a physical barrier to seedling emergence and growth (Teasdale et al., 2007. Materials and Methods: The experiment was carried out in Ardabil Agricultural Research Station, as a factorial experiment based on randomized complete block design with three replications during 1390-1391. The first factor was considered four types of cover crops including winter rye (Secale cereal, spring barley (Hordeum vulgare, winter wheat (Triticum aestivum and control (no cover crop, no weeding.The second factor was mulch management at two levels (living mulch and dead mulch and the third factor was two planting dates for cover crops (synchronous with sunflower planting and 45 days after sunflower planting. Sunflower seeding performed manually on 23 May on the ridges with 50 cm row distance and spacing between plants was 25 cm in depth of 5 cm. Cover crops seeds, rye, barley and wheat, were planted between rows of sunflower. Due to the low density of weeds in study field, complete weeding and sampling of weeds in one session was performed (60 days after planting date sunflower. Statistical analysis of data performed using SAS software and mean comparison performed using Duncan's test with probability level of 5% and 1%. Diagrams drawn using Excel (Version 8.2. Results and Discussion\t: Density and dry weight of Field bindweed (Convolvulus arvensis L
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Utilization of sunflower crop wild relatives for cultivated sunflower improvement
Sunflower (Helianthus annuus L.) is one of the few crops native to the U.S. The current USDA-ARS-NPGS crop wild relatives sunflower collection is the largest extant collection in the world, containing 2,519 accessions comprised of 53 species; 39 perennial and 14 annual. To fully utilize gene bank co...
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BIOCHEMICAL CHANGES IN THE WOUNDS OF GOATS FOLLOWING TREATMENT OF SUNFLOWER OIL AND OLIVE OIL
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Abhishek Anand
2016-06-01
Full Text Available Experimentally created forty eight wounds of similar size and shape were randomly divided in to three groups, of 16 wounds in each group. Sunflower seed oil impregnated gauze were subjected to the wounds of goats belonging to group I, while Olive oil (Olea europaea impregnated gauze were subjected to the wounds of goats of group II and normal saline solution (control soaked gauze to the wounds of goats of group III. Healing tissues were collected from the junction of wound and intact skin from all the experimental wounds in each of the three groups on 3, 10, 15 and 25 days. Biochemical examinations of healing tissue were done for collagen, elastin, hexosamine and hydroxyproline. The level of collagen, elastin, hexosamine and hydroxyproline were significantly higher in group I followed by group II and then group III. It can be concluded that both sunflower oil and olive oil are effective for acceleration of wound healing and sunflower oil is more effective than olive oil.
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International Nuclear Information System (INIS)
Nasim, W.; Ahmad, A.; Wajid, A.; Muhammad, D.
2011-01-01
The effect of nitrogen (N) on growth, development, yield and yield components of different sunflower (Helianthus annuus L.) hybrids was evaluated under agro-climatic conditions of Multan during spring 2008 and 2009. The experiment was laid out in a randomized complete block design with split plot arrangement having three replications, keeping cultivars in the main plots and N levels in the subplots. The net plot size was 4.2 m x 5 m. The results showed that, with increasing N rates, there was increment in the biomass, yield and yield components while the oil contents were adversely affected. However, there was high seed yield in 2008 as compared to 2009. Among sunflower hybrids, Hysun-38 gave more yield as compared to other sunflower hybrids (Hysun-33, Pioneer 64A93), while in case of N levels, 180 kg ha/sup -1/ provided higher yield than other N rates (0, 60, 120, 240 kg ha/sup -1/) in both years of study especially during 2008. (author)
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North Dakota State University Sunflower Research: A Summary of Selected Research Projects
Jacobsen, Roy M.; Sell, Randall S.; Watt, David L.
1992-01-01
Sunflower research in North Dakota focuses on variety testing. Additional research has been conducted on cost-effective cultural practices, possible use to produce a red dye food colorant, and the estimated economic impact of banning an insecticide. Variety testing has been conducted at most state experiment sites in North Dakota, including, Casselton Agronomy Seed Farm, Carrington Research Extension Center, Langdon, Minot, Williston, Dickinson, and Hettinger Experiment Stations. A comparison...
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Bakti Nur Ismuhajaroh
2016-08-01
Full Text Available The purpose of the study was to find out the dormancy breaking and the seed germination of Asam kuranji (Dialium indum L. mechanically by sandpapering the seeds and chemically by immersing them in sulfuric acid (H2SO4. The experiment was conducted at the Plant Physiology Laboratory of Agricultural Faculty of Lambung Mangkurat University from June - August 2013 using Completely Randomized Design (CRD with 2 x 4 factorial. The first factor was the mechanical treatment (s0 = without sandpaper and s1 = with sandpaper, the second factor was the chemical treatment (a0 = without immersion, a1 = 70% of H2SO4, a2 = 80% of H2SO4, and a3 = 90% of H2SO4. The data were analyzed by ANOVA at the level of 95% followed by Tukey's test at the level test of 95%. The results showed that the treatments of sandpapering and immersing the seeds significantly affected the % of germination, the length of radicle and the length of hypocotyl. The interaction between treatments of sandpapering and immersion indicated that the higher the concentration of H2SO4 immersion the higher the % of germination, the length of radicle and the length of hypocotyl. Keywords: germination, Dialium indum L., sandpaper, concentration, H2SO4
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Madelon Rodrigues Sá Braz
2008-10-01
Full Text Available Os testes de vigor têm sido desenvolvidos para diferenciar os lotes de sementes devido às limitações impostas pelo teste de germinação. O objetivo do trabalho foi analisar a eficiência dos testes de envelhecimento acelerado e deterioração controlada na avaliação do vigor de lotes de aquênios de girassol. Para tanto, cinco lotes de aquênios (sementes com o pericarpo de girassol da cultivar "Catissol 01" foram submetidos à determinação do grau de umidade e à avaliação da qualidade fisiológica, empregando os testes de germinação e vigor (primeira contagem, teste de frio, condutividade elétrica, emergência de plântulas, índice de velocidade de emergência, envelhecimento acelerado pelos sistemas tradicional e com solução saturada de NaCl a 42°C por 48, 72, 96 horas e deterioração controlada com teor inicial de água de 15, 20, 25% por 48, 72, 96 horas a 42°C. Os resultados permitiram concluir que o teste de envelhecimento acelerado com solução saturada de NaCl por 96 horas foi eficiente para classificar os lotes de aquênios de girassol. As combinações de 20% de água nos aquênios por 72 horas de exposição e de 25% de água nos aquênios por 48 e 72 horas de exposição permitem classificar os lotes de aquênios de girassol.The vigour tests were developed to detect differences of seeds lots owing to limitations the germination test. This study was conducted to compare different procedures of the accelerated aging and controlled deterioration tests to evaluate sunflowers seed vigour. Five lots of sunflower achenes (seeds with pericarp cv. Catissol 01 were submitted to the water content test and to the evaluation of physiological quality using by germination and vigour test (first count, cold test, electrical conductivity, seedling emergence and speed of emergence index, accelerated aging with tradicional system and satured solution of NaCl, at 42°C for 48, 72, 96 hours and controlled deterioration with 15, 20
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Growth morphology and inheritance of fasciation mutation in sunflower
International Nuclear Information System (INIS)
Jambhulkar, S.J.
2002-01-01
A gamma ray induced fascination mutation was isolated from sunflower variety Surya. Morphological traits and inheritance pattern of the mutant were studied. Fascination mutation was the manifestation of enlarged shoot apex, smaller and more number of leaves with irregular leaf arrangements, significantly higher leaf area and leaf biomass, flattened stem and low seed yield than the parent variety. Inheritance studies indicated that fascination was governed by a single recessive nuclear gene, which may be responsible for the disturbed differentiation of stem and leaves during developmental stages of plant growth [it
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Shuai, Haiwei; Meng, Yongjie; Luo, Xiaofeng; Chen, Feng; Zhou, Wenguan; Dai, Yujia; Qi, Ying; Du, Junbo; Yang, Feng; Liu, Jiang; Yang, Wenyu; Shu, Kai
2017-01-01
Auxin is an important phytohormone which mediates diverse development processes in plants. Published research has demonstrated that auxin induces seed dormancy. However, the precise mechanisms underlying the effect of auxin on seed germination need further investigation, especially the relationship between auxins and both abscisic acid (ABA) and gibberellins (GAs), the latter two phytohormones being the key regulators of seed germination. Here we report that exogenous auxin treatment represse...
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Manipulation of microtubers for direct field utilization in seed production
Pruski, K.; Astatkie, T.; Duplessis, P.; Stewart, L.; Nowak, J.; Struik, P.C.
2003-01-01
A two-year field study was conducted to determine the effects of jasmonic acid (JA), light (during in vitro explant production and in vitro tuberization phases), and dormancy-breaking treatment on performance of microtubers in the production of seed tubers (pre-elite) in five potato cultivars.
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International Nuclear Information System (INIS)
Muhammad, Z.; Mujeed, A.
2014-01-01
Sunflower is a potent allelopathic plant which possesses important allelochemicals with known allelopathic activity on other plants. In this study, allelopathic effects of fresh aqueous extracts (FAE) and air dried aqueous extracts (DAE) of root, shoot and leaves of sunflower (Halianthus annuus L.) were investigated on germination and seedling growth of wheat (Triticum aestivum L.) and maize (Zea mays L.) in seed bioassay experiments carried out at Botany Department of Peshawar University during 2010. Results showed significantly inhibitory effects of aqueous extracts on seed germination, growth and dry biomass of seedlings of wheat and maize. In wheat seedlings, significant germination inhibition (15.21%), increased mean germination time (MGT) (57.76%), reduced plumule and radical growth (21.66 and 28.44%) and lowered seedlings dry biomass (31.05%) were recorded under dry aqueous extracts of leaf when compared to control. Germination percentage of maize was inhibited by dry aqueous extracts of leaf by 7.81%, germination index by 16.51%, increased MGT by 25.53%, decreased plumule and radical lengths by 29.00 and 36.12% respectively, and lowered maize seedling dry biomass by 34.02 %. In both experiments, dry aqueous extracts (DAE) were more phytotoxic than fresh aqueous extracts (FAE). Similarly, inhibitory effects of aqueous extracts of different parts of sunflower were recorded in the order leaf > shoot > root for both tested plants. (author)
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Zhang, Rui; Baskin, J. M.; Baskin, C. C.; Mo, Qing; Chen, Lijun; Hu, Xiaowen; Wang, Yanrong
2017-01-01
Knowledge of the germination behavior of different populations of a species can be useful in the selection of appropriate seed sources for restoration. The aim of this study was to test the effect of seed population, collection year, after-ripening and incubation conditions on seed dormancy and germination of Stipa bungeana, a perennial grass used for revegetation of degraded grasslands on the Loess Plateau, China. Fresh S. bungeana seeds were collected from eight locally-adapted populations ...
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Directory of Open Access Journals (Sweden)
Madelon Rodrigues Sá Braz
2009-10-01
Full Text Available A capacidade do teste de germinação para estimar o potencial de emergência de plântulas no campo diminui à medida que as condições do ambiente são desfavoráveis. No entanto, diferentes testes de vigor têm sido utilizados para identificar os lotes de sementes que apresentam melhor desempenho nessas situações. O objetivo do trabalho foi correlacionar os resultados dos testes conduzidos no laboratório com a emergência das plântulas de girassol em campo. Para isso, cinco lotes de sementes de girassol da cultivar 'Embrapa 122 V2000' foram submetidos aos testes de germinação e vigor (primeira contagem, classificação de plântulas, teste de frio, condutividade elétrica, emergência de plântulas em areia e em campo, índice de velocidade de emergência, envelhecimento acelerado e deterioração controlada. Em condições adversas, a emergência das plântulas de girassol em campo apresentou maior correlação com o vigor, avaliado pelos testes de envelhecimento acelerado, de deterioração controlada e de condutividade elétrica.The germination capacity test to estimate the potential of seedlings emergence in the field decreases when the environmental conditions are unfavorable. However, different vigour tests have been used to identify the seed lots that have better perform in these situations. The objective of this research was to correlate the results of tests conducted in the laboratory with the emergence of sunflower seedlings in the field. For this, five lots of seeds sunflower cultivar 'Embrapa 122 V2000' were submitted to the germination and vigour tests (first count, classification of seedlings, cold test, electrical conductivity, seedling emergence in sand and in the field, emergence speed index, accelerated aging and controlled deterioration. Under adverse conditions, the seed vigour evaluated by accelerated aging, controlled deterioration and electrical conductivity presented higher correlation with sunflower plant
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French environmental communication on sunflower and rapeseed oils based on life cycle assessment
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Badey Laureen
2013-07-01
Full Text Available The French “Grenelle” laws sparked a French national experiment trialling the environmental labelling of fast-moving consumer goods. The data required for this labelling scheme are generated by carrying out a life cycle assessment (LCA. The aim of this study is to provide all necessary information to fit the national experiment for two standard oils: sunflower oil and rapeseed oil. The complete oil life cycle was studied, from oilseed farming through to the end-of-life of the packaging. We focused heavily on the impacts of crushing and refining. The seed processing data was collected from different plants that are representative of the French crushing/refining industry and packaging site practice. The data inventory was used to calculate the identified environmental labelling indicators, i.e. greenhouse gas (GHG emissions and water consumption. The production of 100g of refined bulk sunflower and rapeseed emits 89 and 127 g equivalent CO2 and consumes 1.7 L and 0.8 L of water, respectively. Most impacts on the studied indicators stem from the farming phase. Energy and water consumptions during crushing and refining also weigh on the studied indicators. The results of this study provide a relevant overview of all sunflower and rapeseed oils produced in France, and are usable as standard values for vegetable oil producers and users. Oil supply chain operators can use these values to compare to their own process values and gauge the improvements brought about by their ecodesign strategies. For example, using a biomass boiler, using less packaging, and making different choices on seed suppliers can lead to a lower set of impact values.
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Cochavi, Amnon; Rapaport, Tal; Gendler, Tania; Karnieli, Arnon; Eizenberg, Hanan; Rachmilevitch, Shimon; Ephrath, Jhonathan E
2017-01-01
Broomrape ( Orobanche and Phelipanche spp.) parasitism is a severe problem in many crops worldwide, including in the Mediterranean basin. Most of the damage occurs during the sub-soil developmental stage of the parasite, by the time the parasite emerges from the ground, damage to the crop has already been done. One feasible method for sensing early, below-ground parasitism is through physiological measurements, which provide preliminary indications of slight changes in plant vitality and productivity. However, a complete physiological field survey is slow, costly and requires skilled manpower. In recent decades, visible to-shortwave infrared (VIS-SWIR) hyperspectral tools have exhibited great potential for faster, cheaper, simpler and non-destructive tracking of physiological changes. The advantage of VIS-SWIR is even greater when narrow-band signatures are analyzed with an advanced statistical technique, like a partial least squares regression (PLS-R). The technique can pinpoint the most physiologically sensitive wavebands across an entire spectrum, even in the presence of high levels of noise and collinearity. The current study evaluated a method for early detection of Orobanche cumana parasitism in sunflower that combines plant physiology, hyperspectral readings and PLS-R. Seeds of susceptible and resistant O. cumana sunflower varieties were planted in infested (15 mg kg -1 seeds) and non-infested soil. The plants were examined weekly to detect any physiological or structural changes; the examinations were accompanied by hyperspectral readings. During the early stage of the parasitism, significant differences between infected and non-infected sunflower plants were found in the reflectance of near and shortwave infrared areas. Physiological measurements revealed no differences between treatments until O. cumana inflorescences emerged. However, levels of several macro- and microelements tended to decrease during the early stage of O. cumana parasitism. Analysis of
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Amnon Cochavi
2017-06-01
Full Text Available Broomrape (Orobanche and Phelipanche spp. parasitism is a severe problem in many crops worldwide, including in the Mediterranean basin. Most of the damage occurs during the sub-soil developmental stage of the parasite, by the time the parasite emerges from the ground, damage to the crop has already been done. One feasible method for sensing early, below-ground parasitism is through physiological measurements, which provide preliminary indications of slight changes in plant vitality and productivity. However, a complete physiological field survey is slow, costly and requires skilled manpower. In recent decades, visible to-shortwave infrared (VIS-SWIR hyperspectral tools have exhibited great potential for faster, cheaper, simpler and non-destructive tracking of physiological changes. The advantage of VIS-SWIR is even greater when narrow-band signatures are analyzed with an advanced statistical technique, like a partial least squares regression (PLS-R. The technique can pinpoint the most physiologically sensitive wavebands across an entire spectrum, even in the presence of high levels of noise and collinearity. The current study evaluated a method for early detection of Orobanche cumana parasitism in sunflower that combines plant physiology, hyperspectral readings and PLS-R. Seeds of susceptible and resistant O. cumana sunflower varieties were planted in infested (15 mg kg-1 seeds and non-infested soil. The plants were examined weekly to detect any physiological or structural changes; the examinations were accompanied by hyperspectral readings. During the early stage of the parasitism, significant differences between infected and non-infected sunflower plants were found in the reflectance of near and shortwave infrared areas. Physiological measurements revealed no differences between treatments until O. cumana inflorescences emerged. However, levels of several macro- and microelements tended to decrease during the early stage of O. cumana
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Molecular evolution of candidate genes for crop-related traits in sunflower (Helianthus annuus L.).
Mandel, Jennifer R; McAssey, Edward V; Nambeesan, Savithri; Garcia-Navarro, Elena; Burke, John M
2014-01-01
Evolutionary analyses aimed at detecting the molecular signature of selection during crop domestication and/or improvement can be used to identify genes or genomic regions of likely agronomic importance. Here, we describe the DNA sequence-based characterization of a pool of candidate genes for crop-related traits in sunflower. These genes, which were identified based on homology to genes of known effect in other study systems, were initially sequenced from a panel of improved lines. All genes that exhibited a paucity of sequence diversity, consistent with the possible effects of selection during the evolution of cultivated sunflower, were then sequenced from a panel of wild sunflower accessions an outgroup. These data enabled formal tests for the effects of selection in shaping sequence diversity at these loci. When selection was detected, we further sequenced these genes from a panel of primitive landraces, thereby allowing us to investigate the likely timing of selection (i.e., domestication vs. improvement). We ultimately identified seven genes that exhibited the signature of positive selection during either domestication or improvement. Genetic mapping of a subset of these genes revealed co-localization between candidates for genes involved in the determination of flowering time, seed germination, plant growth/development, and branching and QTL that were previously identified for these traits in cultivated × wild sunflower mapping populations.
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Jiménez, Sergio; Li, Zhigang; Reighard, Gregory L; Bielenberg, Douglas G
2010-02-09
In many tree species the perception of short days (SD) can trigger growth cessation, dormancy entrance, and the establishment of a chilling requirement for bud break. The molecular mechanisms connecting photoperiod perception, growth cessation and dormancy entrance in perennials are not clearly understood. The peach [Prunus persica (L.) Batsch] evergrowing (evg) mutant fails to cease growth and therefore cannot enter dormancy under SD. We used the evg mutant to filter gene expression associated with growth cessation after exposure to SD. Wild-type and evg plants were grown under controlled conditions of long days (16 h/8 h) followed by transfer to SD (8 h/16 h) for eight weeks. Apical tissues were sampled at zero, one, two, four, and eight weeks of SD and suppression subtractive hybridization was performed between genotypes at the same time points. We identified 23 up-regulated genes in the wild-type with respect to the mutant during SD exposure. We used quantitative real-time PCR to verify the expression of the differentially expressed genes in wild-type tissues following the transition to SD treatment. Three general expression patterns were evident: one group of genes decreased at the time of growth cessation (after 2 weeks in SD), another that increased immediately after the SD exposure and then remained steady, and another that increased throughout SD exposure. The use of the dormancy-incapable mutant evg has allowed us to reduce the number of genes typically detected by differential display techniques for SD experiments. These genes are candidates for involvement in the signalling pathway leading from photoperiod perception to growth cessation and dormancy entrance and will be the target of future investigations.
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Cell cycle arrest in plants: what distinguishes quiescence, dormancy and differentiated G1?
Velappan, Yazhini; Signorelli, Santiago; Considine, Michael J
2017-10-17
Quiescence is a fundamental feature of plant life, which enables plasticity, renewal and fidelity of the somatic cell line. Cellular quiescence is defined by arrest in a particular phase of the cell cycle, typically G1 or G2; however, the regulation of quiescence and proliferation can also be considered across wider scales in space and time. As such, quiescence is a defining feature of plant development and phenology, from meristematic stem cell progenitors to terminally differentiated cells, as well as dormant or suppressed seeds and buds. While the physiology of each of these states differs considerably, each is referred to as 'cell cycle arrest' or 'G1 arrest'. Here the physiology and molecular regulation of (1) meristematic quiescence, (2) dormancy and (3) terminal differentiation (cell cycle exit) are considered in order to determine whether and how the molecular decisions guiding these nuclear states are distinct. A brief overview of the canonical cell cycle regulators is provided, and the genetic and genomic, as well as physiological, evidence is considered regarding two primary questions: (1) Are the canonical cell cycle regulators superior or subordinate in the regulation of quiescence? (2) Are these three modes of quiescence governed by distinct molecular controls? Meristematic quiescence, dormancy and terminal differentiation are each predominantly characterized by G1 arrest but regulated distinctly, at a level largely superior to the canonical cell cycle. Meristematic quiescence is intrinsically linked to non-cell-autonomous regulation of meristem cell identity, and particularly through the influence of ubiquitin-dependent proteolysis, in partnership with reactive oxygen species, abscisic acid and auxin. The regulation of terminal differentiation shares analogous features with meristematic quiescence, albeit with specific activators and a greater role for cytokinin signalling. Dormancy meanwhile appears to be regulated at the level of chromatin
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Directory of Open Access Journals (Sweden)
Lihua Zhang
2017-08-01
Full Text Available Genotypic variation at multiple loci for seed dormancy (SD contributes to plant adaptation to diverse ecosystems. Weedy rice (Oryza sativa was used as a model to address the similarity of SD genes between distinct ecotypes. A total of 12 quantitative trait loci (QTL for SD were identified in one primary and two advanced backcross (BC populations derived from a temperate ecotype of weedy rice (34.3°N Lat.. Nine (75% of the 12 loci were mapped to the same positions as those identified from a tropical ecotype of weedy rice (7.1°N Lat.. The high similarity suggested that the majority of SD genes were conserved during the ecotype differentiation. These common loci are largely those collocated/linked with the awn, hull color, pericarp color, or plant height loci. Phenotypic correlations observed in the populations support the notion that indirect selections for the wild-type morphological characteristics, together with direct selections for germination time, were major factors influencing allelic distributions of SD genes across ecotypes. Indirect selections for crop-mimic traits (e.g., plant height and flowering time could also alter allelic frequencies for some SD genes in agroecosystems. In addition, 3 of the 12 loci were collocated with segregation distortion loci, indicating that some gametophyte development genes could also influence the genetic equilibria of SD loci in hybrid populations. The SD genes with a major effect on germination across ecotypes could be used as silencing targets to develop transgene mitigation (TM strategies to reduce the risk of gene flow from genetically modified crops into weed/wild relatives.
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Directory of Open Access Journals (Sweden)
J.M. Vasconcelos
2011-01-01
Full Text Available "Quina" (Strychnos pseudoquina A. St. Hil is a medicinal plant species from the Brazilian Cerrado. As its seeds show dormancy, they were subjected to the treatments pre-cooling at 5ºC during 7 days, pre-heating at 40ºC during 7 days, pre-soaking in sulfuric acid PA during 5 and 15 min, pre-soaking in boiling water during 5 and 15 min, pre-soaking in 100 and 200 ppm gibberellic acid during 48 h, pre-soaking in distilled water during 24 and 48 h, and mechanical scarification to break dormancy. Counts were daily conducted from the 2nd day after the experiment implementation until the germination stabilization at the 65th day. The germination speed index (GSI and the germination percentage were evaluated. Germination rates above 96% were reached in seeds pre-soaked in water during 48 h and substrate moistened with water or KNO3.A quina (Strychnos pseudoquina A. St.-Hil é espécie medicinal do Cerrado Brasileiro. As sementes apresentam dormência e, por isso, foram submetidas aos tratamentos pré-resfriamento a 5ºC durante 7 dias, pré-aquecimento a 40ºC durante 7 dias, pré-embebição em ácido sulfúrico P.A. durante 5 e 15 minutos, pré-embebição em água fervente durante 5 e 15 minutos, pré-embebição em ácido giberélico a 100 e 200 ppm, durante 48 horas, pré-embebição em água destilada durante 24 e 48 horas e escarificação mecânica, visando à superação da dormência. Foram realizadas contagens diárias entre o 2º dia após a implantação do experimento até a estabilização da germinação, que ocorreu no 65º dia. Foram avaliados o índice de velocidade de germinação (IVG e a porcentagem de germinação. Taxas de germinação acima de 96% foram atingidas em sementes pré-embebidas em água durante 48 horas e substrato umedecido com água ou KNO3.
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Breaking of Judas tree seed dormancy by plant hormone treatments
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Grbić Mihailo
2014-01-01
Full Text Available The study deals with the influence of growth regulators on the germination of Judas tree (Cercis siliquastrum L. seed which is double dormant. We simultaneously tested seeds prepared in the conventional procedure: scarification + stratification and scarified seeds treated with phytohormones from the groups of gibberellins, auxin and cytokinins. The results indicate a positive effect of gibberellic acid (GA, as well as some combinations of this phytohormone with others. Recommendations for practice are to combine the conventional procedure with GA. The procedure may shorten the duration of stratification; the application of GA should follow stratification because the temperature of 4°C does not provide growth regulators activity. The study results can serve as the base for easier generative reproduction of this valuable woody ornamental species which could have a wide use in changed climate conditions. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation
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Differential dormancy of co-occurring copepods
Ohman, Mark D.; Drits, Aleksandr V.; Elizabeth Clarke, M.; Plourde, Stéphane
1998-08-01
Four species of planktonic calanoid copepods that co-occur in the California Current System ( Eucalanus californicus Johnson, Rhincalanus nasutus Giesbrecht, Calanus pacificus californicus Brodsky, and Metridia pacifica Brodsky) were investigated for evidence of seasonal dormancy in the San Diego Trough. Indices used to differentiate actively growing from dormant animals included developmental stage structure and vertical distribution; activity of aerobic metabolic enzymes (Citrate Synthase and the Electron Transfer System complex); investment in depot lipids (wax esters and triacylglycerols); in situ grazing activity from gut fluorescence; and egg production rates in simulated in situ conditions. None of the 4 species exhibited a canonical calanoid pattern of winter dormancy - i.e., synchronous developmental arrest as copepodid stage V, descent into deep waters, reduced metabolism, and lack of winter reproduction. Instead, Calanus pacificus californicus has a biphasic life history in this region, with an actively reproducing segment of the population in surface waters overlying a deep dormant segment in winter. Eucalanus californicus is dormant as both adult females and copepodid V's, although winter females respond relatively rapidly to elevated food and temperature conditions; they begin feeding and producing eggs within 2-3 days. Rhincalanus nasutus appears to enter dormancy as adult females, although the evidence is equivocal. Metridia pacifica shows no evidence of dormancy, with sustained active feeding, diel vertical migration behavior, and elevated activity of metabolic enzymes in December as well as in June. The four species also differ markedly in water content, classes of storage lipids, and specific activity of Citrate Synthase. These results suggest that copepod dormancy traits and structural composition reflect diverse adaptations to regional environmental conditions rather than a uniform, canonical series of traits that remain invariant among taxa
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Physico-Chemical Evaluation of Honey Fortified with Oleaginous Seeds
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Ariana Bianca Velciov
2014-11-01
Full Text Available This research followed to achieve some natural-fortified food, based on honey and oleaginous fruits. Honey and oleaginous fruits are extremely valuable for human diet. With their rich nutrient content, new products obtained by mixing honey with seeds may be considered both traditional food with high nutritional value as well as fortified food. The samples were constituted from acacia flowers honey bought directly from the producer, to which were added various quantities of oleaginous fruits (seeds. Thus, we obtained 3 different types of fortified honey, using pumpkin seeds, sunflower seeds and hemp seeds. Samples obtained were stored in appropriate conditions. From these samples, were made analytical tests: ascorbic acid and humidity.
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Bio-Derived Hierarchical 3D Architecture from Seeds for Supercapacitor Application
Intawin, Pratthana; Sayed, Farheen N.; Pengpat, Kamonpan; Joyner, Jarin; Tiwary, Chandra Sekhar; Ajayan, Pulickel M.
2017-09-01
The generation and storage of green energy (energy from abundant and nonfossil) is important for a sustainable and clean future. The electrode material in a supercapacitor is a major component. The properties of these materials depend on its inherent architecture and composition. Here, we have chosen sunflower seeds and pumpkin seeds with a completely different structure to obtain a carbonaceous product. The product obtained from sunflower seed carbon is a three-dimensional hierarchical macroporous carbon (SSC) composed of many granular nanocrystals of potassium magnesium phosphate dispersed in a matrix. Contrary to this, carbon from pumpkin seeds (PSC) is revealed to be a more rigid structure, with no porous or ordered morphology. The electrochemical supercapacitive behavior was assessed by cyclic voltammetry and galvanostatic charge-discharge tests. Electrochemical measurements showed that the SSC shows a high specific capacitance of 24.9 Fg-1 as compared with that obtained (2.46 Fg-1) for PSC with a cycling efficiency of 87% and 89%, respectively. On high-temperature cycling for 500 charge-discharge cycles at 0.1 Ag-1, an improved cycling efficiency of 100% and 98% for SSC and PSC, respectively, is observed.
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Directory of Open Access Journals (Sweden)
Jelena Lević
2012-01-01
Full Text Available A total of 41 species of fungi were isolated from seed samples of barley, maize, soybean,and sunflower collected at different locations in Serbia. The majority of detected speciesoccurred on barley (35 of 41 species or 87.8% comparing to soybean (17 of 41 species or41.5%, sunflower (16 of 41 species or 39.0% and maize (15 of 41 species or 36.9%. Speciesbelonging to genera Alternaria, Chaetomium, Epicoccum, Fusarium, Penicillium and Rhizopuswere present on seeds of all four plant species. Alternaria species were dominant on soybean,barley and sunflower seeds (85.7%, 84.7% and 76.9%. F. verticillioides and Penicilliumspp. were mainly isolated from maize seeds (100 and 92.3% respectively, while other specieswere isolated up to 38.5% (Chaetomium spp. and Rhizopus spp.. F. graminearum, F. proliferatum,F. poae and F. sporotrichioides were the most common Fusarium species isolatedfrom barley (51.1-93.3%, while on the soybean seeds F. oxysporum (71.4%, F. semitectum(57.1% and F. sporotrichioides (57.1% were prevalent. Frequency of Fusarium species onsunflower seeds varied from 7% (F. equiseti, F. graminearum, F. proliferatum and F. subglutinansto 15.4% (F. verticillioides. Statistically significant negative correlation (r = –0.678* wasdetermined for the incidence of F. graminearum and Alternaria spp., as well as, Fusarium spp.and Alternaria spp. (r = –0.614*, on barley seeds. The obtained results revealed that seedbornepathogens were present in most seed samples of important cereals and industrialcrops grown under different agroecological conditions in Serbia. Some of the identifiedfungi are potential producers of mycotoxins, thus their presence is important in termsof reduced food safety for humans and animals. Therefore, an early and accurate diagnosisand pathogen surveillance will provide time for the development and the applicationof disease strategies.
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Chiu, Rex S; Nahal, Hardeep; Provart, Nicholas J; Gazzarrini, Sonia
2012-01-27
Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3) is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP) during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying germination at supraoptimal temperature. Physiologically, this is
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Directory of Open Access Journals (Sweden)
Chiu Rex S
2012-01-01
Full Text Available Abstract Background Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3 is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. Results In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. Conclusion In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying
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Effect of tannery effluents on seed germination and growth of two ...
African Journals Online (AJOL)
Effect of tannery effluents on seed germination and growth of two sunflower cultivars. ... oxygen demand (COD) values along with much higher concentrations of total ... Vegetative growth parameters like plant height and number of leaves per ...
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Dekkers, B.J.W.; Hanson, S.J.|info:eu-repo/dai/nl/304822299; Willems, L.A.J.; Jamar, D.C.L.; Cueff, Gwendal; Raijou, G.; Hilhorst, H.W.M.; Bentsink, L.|info:eu-repo/dai/nl/241338735
2016-01-01
The seed expressed gene DELAY OF GERMINATION (DOG) 1 is absolutely required for the induction of dormancy. Next to a non-dormant phenotype, the dog1-1 mutant is also characterized by a reduced seed longevity suggesting that DOG1 may affect additional seed processes as well. This aspect however, has
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Dekkers, B.J.W.; He, Hanzi; Hanson, Johannes; Willems, L.A.J.; Jamar, D.C.L.; Cueff, Gwendal; Rajjou, Loïc; Hilhorst, H.W.M.; Bentsink, Leónie
2016-01-01
The seed expressed gene DELAY OF GERMINATION (DOG) 1 is absolutely required for the induction of dormancy. Next to a non-dormant phenotype, the dog1-1 mutant is also characterized by a reduced seed longevity suggesting that DOG1 may affect additional seed processes as well. This aspect however,
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de Souza, Paulo S A; Cerqueira, Alexandre A; Rigo, Michelle M; de Paiva, Julieta L; Couto, Rafael S P; Merçon, Fábio; Perez, Daniel V; Marques, Monica R C
2017-05-01
This study aims to evaluate the effects of oilfield water (OW), treated by a hybrid process of electrocoagulation and reverse osmosis (EC-RO), on seed germination and early growth characteristics of sunflower (Heliantus annus L.). In the EC step, tests were conducted with 28.6 A m -2 current density and 4 min. reaction time. In the RO step, the system was operated with 1 L min -1 constant flow and 2 MPa, 2.5 MPa and 3 MPa feed pressures. In all feed pressures, RO polymeric membranes achieved very high removals of chemical oxygen demand (up to 89%) and oils and greases (100%) from EC-treated effluent. In best feed pressure (2.5 MPa), turbidity, total dissolved salts, electrical conductivity, salinity, toxic ions and sodium adsorption ratio values attained internationally recognized standards for irrigation water. Using EC-RO (feed pressure:2.5 MPa) treated OW, germinated sunflower seeds percentage (86 ± 6%), speed of germination (30 ± 2) and biomass production (49 ± 5 mg) were statistically similar to control (distilled water) results. Vigor index average values obtained using OW treated by EC-RO (3871)were higher than that obtained by OW water treated by EC (3300). The results of this study indicate that EC-RO seems to be a promising alternative for treatment of OW aiming sunflower crops irrigation, since the use of this treated effluent did not affect adversely seed germination and seedling development, and improved seedling vigor. Furthermore, OW treatment by EC-RO reduces sodium levels into acceptable standards values avoiding soil degradation.
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Directory of Open Access Journals (Sweden)
Mostafa Heidari
2014-01-01
Full Text Available The role of arbuscular mycorrhizal fungi in alleviating water stress is well documented. In order to study the effects of water stress and two different mycorrhiza species on grain yield, nutrient uptake and oil content of sunflower, a field experiment as split plot design with three replications was conducted in the Research Field Station, Zabol University, Zabol, Iran in 2011. Water stress treatments included control as 90% of field capacity (W1, 70% field capacity (W2 and 50% field capacity (W3 assigned to the main plots and two different mycorrhiza species, consisting of M1 = control (without any inoculation, M2 = Glumus mossea and M3 = Glumus etanicatum as sub plots. Results showed that by increasing water stress from control (W1 to W3 treatment, grain yield was significantly decreased. The reduction in the level of W3 was 15.05%. The content of potassium in seeds significantly decreased due to water stress but water stress upto W2 treatment increased the content of phosphorus, nitrogen and oil content of seeds. In between two species of mycorrhiza in sunflower plants, Glumus etanicatum had the highest effect on grain yield and these elements in seeds and increased both.
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Directory of Open Access Journals (Sweden)
Claudinei Andreoli
2006-12-01
Full Text Available Pre-harvest sprouting (PHS damage leads to occasional massive losses in all wheat producing areas, causing downgrading of grain quality, that severely limits end-use applications and results in substantial financial losses to farmers and food processors. Red grain color is a traditional marker for resistance to sprouting in wheat breeding programs, however red-grained genotype alone does not always guarantee effective resistance. The objective of this work was to find genes for resistance to PHS and investigate its inheritance in Brazilian wheat cultivars. Genetic variation for dormancy was investigated in the parents, F1 and 300 F2 lines derived from the cross Frontana × OR1 and its reciprocal. The germination/dormancy sprouted grains was evaluated on fifty seeds per replication, germinated in paper towel rolls at 20ºC for 5 days. A bimodal distribution for dormancy occurred in the Frontana/OR1 and OR1/Frontana derived F2 populations. The mean ratio of dormant and non-dormant seeds of the cross and its reciprocal was 85:1115, fitting a digenic model of 1:15 (P Germinação precoce na espiga (PHS ocasiona perdas significativas nas regiões produtoras de trigo, causando depreciação na qualidade do produto final, o que resulta em prejuízos para os produtores e os moageiros. A cor vermelha do grão é um marcador tradicional para resistência à germinação nos programas de melhoramento de trigo, todavia, o genótipo de grão vermelho sózinho não garante resistência efetiva. O objetivo desse trabalho foi encontrar gene(s para resistência à PHS e estudar a herança do caráter dormência de semente nos cultivares de trigo brasileiro. A variação genética para dormência foi investigada nos parentais, no F1 e em 300 linhas F2 derivadas do cruzamento de Frontana × OR1, e o cruzamento recíproco. Os grãos brotados (sprouted e os dormentes foram avaliados pelo teste de germinação, em rolo de papel, a 20º C por 5 dias. Observou-se uma
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Redefining reproductive dormancy in Drosophila as a general stress response to cold temperatures.
Lirakis, Manolis; Dolezal, Marlies; Schlötterer, Christian
2018-04-09
Organisms regularly encounter unfavorable conditions and the genetic adaptations facilitating survival have been of long-standing interest to evolutionary biologists. Winter is one particularly stressful condition for insects, during which they encounter low temperatures and scarcity of food. Despite dormancy being a well-studied adaptation to facilitate overwintering, there is still considerable controversy about the distribution of dormancy among natural populations and between species in Drosophila. The current definition of dormancy as developmental arrest of oogenesis at the previtellogenic stage (stage 7) distinguishes dormancy from general stress related block of oogenesis at early vitellogenic stages (stages 8 - 9). In an attempt to resolve this, we scrutinized reproductive dormancy in D. melanogaster and D. simulans. We show that dormancy shows the same hallmarks of arrest of oogenesis at stage 9, as described for other stressors and propose a new classification for dormancy. Applying this modified classification, we show that both species express dormancy in cosmopolitan and African populations, further supporting that dormancy uses an ancestral pathway induced by environmental stress. While we found significant differences between individuals and the two Drosophila species in their sensitivity to cold temperature stress, we also noted that extreme temperature stress (8 °C) resulted in very strong dormancy incidence, which strongly reduced the differences seen at less extreme temperatures. We conclude that dormancy in Drosophila should not be considered a special trait, but is better understood as a generic stress response occurring at low temperatures. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Elucidating hormonal/ROS networks during seed germination: insights and perspectives
DEFF Research Database (Denmark)
Diaz-Vivancos, Pedro; Barba Espin, Gregorio; Hernández, José Antonio
2013-01-01
” technologies together with physiological and biochemical approaches have revealed that seed germination is a very complex process that depends on multiple biochemical and molecular variables. The pivotal role of phytohormones in promoting germination now appears to be interdependent with ROS metabolism......While authors have traditionally emphasized the deleterious effects of reactive oxygen species (ROS) on seed biology, their role as signaling molecules during seed dormancy alleviation and germination is now the focus of many studies around the world. Over the last few years, studies using “-omics......, involving mitogen-activated protein kinase cascade activation, gene expression and post-translational protein modifications. This review is, thus, an attempt to summarize the new discoveries involving ROS and seed germination. The study of these interactions may supply markers of seed quality that might...