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Sample records for early seedling development

  1. Sowing on the emergence and early development of seedlings o baru

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    Alan Mario Zuffo

    2014-09-01

    Full Text Available The objective of this work to evaluate the influence of the position of baru seeds, the emergence and early seedling development. The test was conducted in a greenhouse experiment in randomized blocks, with five treatments (seeding position, with four replications, positions were: A - Hilo up, B - hilo down C - hilum and raphe aside, D - horizontal raphe up, E - horizontal raphe down. It was observed that the seeds deposited at the position B (heel down provided better emergence and seedling development. We evaluated the emergence, speed of emergence index, plant height, stem diameter, root length, dry mass of air, root dry weight, relative AP/DC, FSPA/FSR and Dickson quality index. The emergence and early seedling development baru were influenced by sowing position. The seeds deposited with the hilum down provided better results.

  2. A comparison of growth, photosynthetic capacity and water stress in Eucalyptus globulus coppice regrowth and seedlings during early development.

    Science.gov (United States)

    Drake, Paul L; Mendham, Daniel S; White, Don A; Ogden, Gary N

    2009-05-01

    Eucalyptus globulus Labill., a globally significant plantation species, is grown commercially in a multiple rotation framework. Second and subsequent crops of E. globulus may be established either by allowing the cut stumps to resprout (commonly referred to as coppice) or by replanting a new crop of seedlings. Currently, long-term growth data comparing coppice and seedling productivity in second or later rotations in southern Australia is limited. The capacity to predict productivity using these tools is dependent on an understanding of the physiology of seedlings and coppice in response to light, water and nutrient supply. In this study, we compared the intrinsic (independent of the immediate environment) and native (dependent on the immediate environment) physiology of E. globulus coppice and second-generation seedlings during their early development in the field. Coppice not only grew more rapidly, but also used more water and drew on stored soil water to a depth of at least 4.5 m during the first 2 years of growth, whereas the seedlings only accessed the top 0.9 m of the soil profile. During the same period, there was no significant difference between coppice and seedlings in either their stomatal response to leaf-to-air vapour pressure difference (D) or intrinsic water-use efficiency; CO(2)- and light-saturated rates of photosynthesis were greater in seedlings than that in coppice as were the quantum yield of photosynthesis and total leaf chlorophyll content. Thus, at a leaf scale, seedlings are potentially more productive per unit leaf area than coppice during early development, but this is not realised under ambient conditions. The underlying cause of this inherent difference is discussed in the context of the allocation of resources to above- and below-ground organs during early development.

  3. Provenances and fertilizer on early growth cedar seedlings

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    Marcio Carlos Navroski

    2016-03-01

    Full Text Available The aim of the study was to evaluate the initial development of different provenances and the influence of base fertilizer and coverage on growth of Cedrela fissilis seedlings. Provenances of seeds were collected in Lapa, PR, Fernandes Pinheiro, PR and Itaara, RS. After germination, the seedlings were transplanted to plastic bags of 500 cm³, filled with commercial substrate. Total height (h, stem diameter (sd, and ratio h/sd seedlings were measured after 150 days of transplanting. Seedlings of Fernandes Pinheiro received basic fertilization after transplantation (0, 2, 4, 6 and 8 g dm-3  Osmocote® and cover (3 and 6 g L-1, respectively, of Peter’s® and urea. The provenance and doses of controlled-release fertilizer influenced early development of Cedrela fissilis seedlings. Itaara provenance showed better seedlings growth. Cedar seedlings showed good growth when incorporated into the substrate 5 g dm-3 Osmocote® and, in addition, applied in topdressing 3 g L-1 of Peter’s®. Urea topdressing is rarely recommended for cedar seedlings.

  4. Arabidopsis WRKY6 Transcription Factor Acts as a Positive Regulator of Abscisic Acid Signaling during Seed Germination and Early Seedling Development.

    Science.gov (United States)

    Huang, Yun; Feng, Cui-Zhu; Ye, Qing; Wu, Wei-Hua; Chen, Yi-Fang

    2016-02-01

    The phytohormone abscisic acid (ABA) plays important roles during seed germination and early seedling development. Here, we characterized the function of the Arabidopsis WRKY6 transcription factor in ABA signaling. The transcript of WRKY6 was repressed during seed germination and early seedling development, and induced by exogenous ABA. The wrky6-1 and wrky6-2 mutants were ABA insensitive, whereas WRKY6-overexpressing lines showed ABA-hypersensitive phenotypes during seed germination and early seedling development. The expression of RAV1 was suppressed in the WRKY6-overexpressing lines and elevated in the wrky6 mutants, and the expression of ABI3, ABI4, and ABI5, which was directly down-regulated by RAV1, was enhanced in the WRKY6-overexpressing lines and repressed in the wrky6 mutants. Electrophoretic mobility shift and chromatin immunoprecipitation assays showed that WRKY6 could bind to the RAV1 promoter in vitro and in vivo. Overexpression of RAV1 in WRKY6-overexpressing lines abolished their ABA-hypersensitive phenotypes, and the rav1 wrky6-2 double mutant showed an ABA-hypersensitive phenotype, similar to rav1 mutant. Together, the results demonstrated that the Arabidopsis WRKY6 transcription factor played important roles in ABA signaling by directly down-regulating RAV1 expression.

  5. Sugar signalling during germination and early seedling establishment in Arabidopsis

    NARCIS (Netherlands)

    Dekkers, S.J.W.

    2006-01-01

    Sugars have pronounced effects on many plant processes like gene expression, germination and early seedling development. Several screens for sugar insensitive mutants were performed to identify genes involved in sugar response pathways using the model plant Arabidopsis. These include sun, gin and si

  6. Nutrient partitioning and seedling development in the genus Leucaena

    Energy Technology Data Exchange (ETDEWEB)

    Dovel, R.L.

    1987-01-01

    Slow establishment of the genus Leucaena from seed has been attributed to law seedling vigor and late nodulation. Observation of early seedling growth indicated that partitioning of a large proportion of resources to the root of young Leucaena seedlings could account, in part, for the slow initial shoot growth observed in this genus. Therefore, a series of experiments were conducted to examine the partitioning of stored seed reserves, photosynthate, and nitrogen in developing Leucaena seedlings. The effects of nodulation and nitrogen fertilization on partitioning of nutrients in the seedling were also examined. Seed reserves were initially used for radicle growth in dark grown seedlings; however, partitioning soon shifted to the hypocotyl. By four days after imbibition, hypocotyl weight exceeded radicle weight in both species tested (L. leucocephala and L. retusa), at all temperatures above 20/sup 0/C. Two experiments were conducted examining the carbon partitioning of L. leucocephala cultivar K-8 using /sup 14/CO/sub 2/ pulse labeling techniques.

  7. Voltage-Dependent Anion Channel 2 of Arabidopsis thaliana (AtVDAC2 Is Involved in ABA-Mediated Early Seedling Development

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    Xufeng Li

    2009-05-01

    Full Text Available The voltage-dependent anion channel (VDAC is the major transport protein in the outer membrane of mitochondria and plays crucial roles in energy metabolism, apoptosis, and metabolites transport. In plants, the expression of VDACs can be affected by different stresses, including drought, salinity and pathogen defense. In this study, we investigated the expression pattern of AtVDAC2 in A. thaliana and found ABA suppressed the accumulation of AtVDAC2 transcripts. Further, phenotype analysis of this VDAC deregulated-expression transgenic Arabidopsis plants indicated that AtVDAC2 anti-sense line showed an ABA-insensitivity phenotype during the early seedling development under ABA treatment. The results suggested that AtVDAC2 might be involved in ABA signaling in A. thaliana.

  8. Identification and characterization of a matrix metalloproteinase (Pta1-MMP) expressed during Loblolly pine (Pinus taeda) seed development, germination completion, and early seedling establishment.

    Science.gov (United States)

    Ratnaparkhe, Supriya M; Egertsdotter, E M Ulrika; Flinn, Barry S

    2009-07-01

    Extracellular matrix (ECM) modifications occur during plant growth, development, and in response to environmental stimuli. Key modulators of ECM modification in vertebrates, the extracellular matrix metalloproteinases (MMPs), have also been described in a few plants. Here, we report the identification of Loblolly pine (Pinus taeda) Pta1-MMP and its characterization during seed development and germination. Pta1-MMP protein has the structural characteristics of other plant MMPs, the recombinant protein exhibits Zn(2+)-dependent protease activity, and is inhibited by EDTA and the active site-binding hydroxamate inhibitor GM6001. The Pta1-MMP gene is expressed in both embryo and megagametophyte, with transcript levels increasing in both during the period from proembryo to early cotyledonary stage, then declining during late embryogenesis and maturation drying. Protein extracts exhibited similar developmental-stage MMP-like activity. Seed germination was stimulated by GA(3) and inhibited by ABA, and the timing of germination completion was mirrored by the presence of MMP-like protease activity in both water- and GA(3)-imbibed embryos. Pta1-MMP gene transcript levels increased in association with radicle protrusion for both GA(3)- and water-treated embryos, in agreement with MMP-like activity. In contrast, by 11 days after imbibition, Pta1-MMP gene transcripts in ABA-treated embryos were at levels similar to the other treatments, although MMP-like activity was not observed. The application of GM6001 during Loblolly pine seed germination inhibited radicle protrusion. Our results suggest that MMP activity may be involved in ECM modification, facilitating the cell division and expansion required during seed development, germination completion, and subsequent seedling establishment.

  9. Germinação de sementes e desenvolvimento inicial de plântulas de achachairu Seeds germination and seedlings early development of achachairu

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    Wilson Barbosa

    2008-03-01

    Full Text Available O achachairu (Garcinia sp, fruta largamente produzida na Bolívia, vem sendo comercializado no Brasil há vários anos. O fruto é globoso-oblongo, de polpa branca, suculenta e textura mucilaginosa e de sabor doce-acidulado equilibrado (ºBrix 15 e pH 4,1. Devido ao crescente interesse em seu cultivo no Brasil, pesquisaram-se a germinação das sementes e o desenvolvimento das plântulas durante os primeiros 12 meses após sua emergência. As sementes, extraídas de frutos bem maduros, foram postas a germinar em duas situações: 1 ambiente controlado em estufa tipo B.O.D., sob as temperaturas de 25 e 30 ºC, fotoperíodo de 16 horas e irradiância de 32 µmol.m-1.s-1, e 2 ambiente de temperatura não-controlada: 3 B.O.D, cuja temperatura oscilava entre 20 e 30 ºC, e 4 sob temperatura ambiente de laboratório (25± 2 ºC. O melhor resultado foi obtido na temperatura constante de 30 ºC, com germinação de 92% e índice de velocidade de germinação (IVG de 0,255. Quando germinada em ambiente de laboratório, a germinação das sementes mostrou-se baixa (30%, com IVG de 0,015. O desenvolvimento das plântulas em casa de vegetação ocorreu de forma bastante lenta, principalmente nas primeiras semanas após a emergência. O primeiro par de folhas surgiu após três semanas da emergência das plântulas, quando essas mediam 8 cm em média. A partir do oitavo mês de desenvolvimento, as plântulas emitiram várias ramificações laterais a partir da porção mediana para a região apical.The achachairu (Garcinia sp, a fruit widely grown in Bolivia, has been commercialized in Brazil for many years. The fruit is globular-oblong shaped, with a white succulent pulp, mucilaginous texture and a well balanced sweet-acid flavor (ºBrix 15; pH 4.1. Due to the increasing interest in its cultivation in Brazil, this work was carried out aiming to study the seeds germination and seedling development throughout the first 12 months after seed emergence. The

  10. Effect of saline water irrigation on seed germination and early seedling growth of the halophyte quinoa

    DEFF Research Database (Denmark)

    Panuccio, M.R.; Jacobsen, Sven-Erik; Saleem Akhtar, Saqib;

    2014-01-01

    been carried out to investigate the mechanisms used by quinoa, a facultative halophytic species, in order to cope with high salt levels at various stages of its develop- ment. Quinoa is regarded as one of the crops that might sustain food security in this century, grown primarily for its edible seeds...... of SW and different salts on seed germination, seedling emergence and the antioxidative pathway of quinoa. Seeds were germi- nated in Petri dishes and seedlings grown in pots with SW solutions (25, 50, 75 and 100 %) and NaCl, CaCl2, KCl and MgCl2 individually, at the concentrations in which...... parameters affected were root and shoot length, root morphology, fresh and dry weight, and water content. An efficient antioxidant mechanism was present in quinoa, activated by salts during germination and early seedling growth, as shown by the activities of antioxidant enzymes. Total antioxidant capacity...

  11. Longleaf pine bud development: influence of seedling nutrition

    Science.gov (United States)

    J. P. Barnett; D. P. Jackson; R. K. Dumroese

    2010-01-01

    A subset of seedlings from a larger study (Jackson and others 2006, 2007) were selected and evaluated for two growing seasons to relate bud development, and root-collar diameter (RCD), and height growth with three nursery fertilization rates. We chose seedlings in the 0.5 (lowest), 2.0 (mid-range), and 4.0 (highest) mg of nitrogen per seedling treatments. Buds moved...

  12. Production and development of eucalyptus seedlings in function of doses of phosphorus

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    José Henrique Tertulino Rocha

    2013-12-01

    Full Text Available This study evaluated the effect of phosphorus (P on the survival in the nursery and early development in the field of clonal Eucalyptus urophylla x Eucalyptus grandis seedlings. The experimental design was completely randomized with four treatments and five replicates of 30 plants per replicate. At the end of the cycle (90 days, 15 seedlings were used for determining the dry matter accumulation and nutrient concentration in the shoot. The rest was planted in the field to determine the percentage of survival and early development. The treatments consisted of four doses of P fertilization (0.0, 1.3, 2.6 and 5.2 mg plant-1. To obtain high quality seedlings in conditions similar to this experiment it is required doses of P in the range from 3.6 to 3.8 mg plant-1. Doses greater than 4 mg plant-1 affect the development and quality of eucalyptus seedlings. An adequate phosphorus fertilization of eucalyptus seedlings increase, by about 30%, the percentage of surviving seedlings in the field.

  13. Germination and initial development of aroeira (Myracrodruon urundeuva seedlings

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    Silvana de Paula Quintão Scalon

    2012-12-01

    Full Text Available Aroeira has great economic importance due to its wood useful, tannins extraction and use in the pharmacology. The aim of this work was to evaluate the germination aspects and initial seedlings development of aroeira, under gibberellins, substrata and shading effects, and for that two experiments were led out. In the first one, seeds were previously soaked for 24 hours in water and in 100 mg.L-1 gibberellin solution and were sowed directly in cells trays in the following substrata: land and sand (1:1 and 1:2 and Plantmax . In the second experiment, 15 cm length seedlings were transplanted to polyethylene sacks filled out land+sand+poultry manure (1:1:1 partly decomposed and they were maintained at greenhouse for 15 days. Soon after, seedlings were transferred for the following conditions: shading (50% and full sun and they were 50 mg.L-1 and 150 mg.L-1 gibberellins solutions pulverized, as control seedlings water pulverized. Aroeira seeds should not be previously water or gibberellins imbibed before being sowed. The best substrata for aroeira seeds germination was Plantmax without germinative treatments to reach higher than 80% of seedlings survival. The seedlings developed better at full sun light and the gibberellin. It was observed increment in height, diameter, foliar area and fresh and dry mass from aerial and root part when compared to shading situation. The gibberellins applications did not influence the aroeira seedlings initial growth characteristics.

  14. Desenvolvimento inicial de mudas de copaíba sob diferentes níveis de sombreamento e substratos Early development of seedlings of copaiba under different shade levels and substrates

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    Tiago Reis Dutra

    2012-06-01

    CA+15VC; four levels of shading (full sunlight (0%, 30, 50 and 70% and three replications. We evaluated the following variables: absolute growth rate in height and diameter, survival, dry mass of leaves, stem and root, total dry mass, dry mass ratio of shoot and root dry weight, and leaf weight. The results show that the seedlings need shade Copaiba in its early stage of development, and the level of 50% shading a viable alternative for production of its seedlings. The seedlings grown in Copaiba 70V+30CA produced more total dry mass, while in Bioplant® inferior characteristics observed for dry weight of leaves, total dry weight and leaf weight.

  15. Identification of QTLs for Drought Resistance of Maize Germination and Seedling Development

    Institute of Scientific and Technical Information of China (English)

    H.W. Zhang; Y.J. Liu; Z.B. Tan

    2007-01-01

    @@ In most maize-growing areas yield reductions due to drought have been observed (Frova et al., 1999; Li et al., 2003; Ribaut et al., 1997; Sari-Gorla et al., 1999). Seed germination and early seedling growth is the primary stage for maize development.

  16. Within-population variability influences early seedling establishment in four Mediterranean oaks

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    González-Rodríguez, Victoria; Barrio, Isabel C.; Villar, Rafael

    2012-05-01

    Regeneration of Mediterranean forests is severely limited. Multiple abiotic factors are known to constrain the establishment of woody seedlings at its first phases, such as summer drought or excessive incident radiation, but less attention has been paid to the role of intra-specific variation in seedling performance. In this study we investigate the relative influence of environment (light availability, soil moisture and summer irrigation) and intrinsic factors (seed mass and maternal origin) as determinants of within-population variability in the early establishment of four coexisting Mediterranean oaks (Quercus ilex, Quercus suber, Quercus faginea and Quercus pyrenaica), from emergence and early growth to second-year survival in a field experiment. Seed size was a poor predictor of seed and seedling success. Instead, mother identity showed a stronger effect on seedling performance. Time and percentage of emergence, establishment success and morphological traits varied among seedlings from different maternal trees but main drivers for each variable were different for each species. In addition to a direct effect, in many cases mother-related intrinsic traits and seed mass influenced the effects of environmental conditions on seedling performance. The role of intrinsic factors was masked under ameliorated conditions (i.e. summer irrigation), indicating the relevant role of within-population variability to cope with highly heterogeneous and unpredictable Mediterranean environments.

  17. A Mutation in Arabidopsis SEEDLING PLASTID DEVELOPMENT1 Affects Plastid Differentiation in Embryo-Derived Tissues during Seedling Growth1[W][OA

    Science.gov (United States)

    Ruppel, Nicholas J.; Logsdon, Charles A.; Whippo, Craig W.; Inoue, Kentaro; Hangarter, Roger P.

    2011-01-01

    Oilseed plants like Arabidopsis (Arabidopsis thaliana) develop green photosynthetically active embryos. Upon seed maturation, the embryonic chloroplasts degenerate into a highly reduced plastid type called the eoplast. Upon germination, eoplasts redifferentiate into chloroplasts and other plastid types. Here, we describe seedling plastid development1 (spd1), an Arabidopsis seedling albino mutant capable of producing normal green vegetative tissues. Mutant seedlings also display defects in etioplast and amyloplast development. Precocious germination of spd1 embryos showed that the albino seedling phenotype of spd1 was dependent on the passage of developing embryos through the degreening and dehydration stages of seed maturation, suggesting that SPD1 is critical during eoplast development or early stages of eoplast redifferentiation. The SPD1 gene was found to encode a protein containing a putative chloroplast-targeting sequence in its amino terminus and also domains common to P-loop ATPases. Chloroplast localization of the SPD1 protein was confirmed by targeting assays in vivo and in vitro. Although the exact function of SPD1 remains to be defined, our findings reveal aspects of plastid development unique to embryo-derived cells. PMID:21045120

  18. Early summer drought stress during the first growing year stimulates extra shoot growth in oak seedlings (Quercus petraea

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    Arion eTurcsán

    2016-02-01

    Full Text Available More severe summer droughts are predicted for mid-latitudes in Europe. To evaluate the impact on forest ecosystems and more specifically on forest regeneration, we studied the response to summer drought in oak seedlings (Quercus petraea. Acorns were collected from different mother trees in three stands in Belgium, sown in pots and grown in non-heated greenhouse conditions. We imposed severe drought on the seedlings in early summer by first watering the pots to saturation and then stopping any watering. Weight of the pots and stomatal conductance were regularly measured. Re-watering followed this drought period of five weeks. Height of the seedlings and apical bud development were observed. Stomatal resistance increased towards the end of the experiment in the drought-treated group and was restored after re-watering. The seedlings from the drought treatment displayed a higher probability to produce additional shoot growth after re-watering (p ≤ 0.05. A higher competition for resources (two plants per pot increased this chance. Although this chance was also higher for smaller seedlings, the actual length of the extra growth after re-watering was higher for larger seedlings (p ≤ 0.01. Both in the drought-treated and in the control group the autochthonous provenance growing on a xeric site produced less extra shoots compared to the two other provenances. Finally, stressed plants showed less developed apical buds compared to the control group after re-watering, suggesting a phenological effect on the growth cycle of oaks (p ≤ 0.0001. The higher chance for an extra shoot growth after the drought period can be considered as a compensation for the induced growth arrest during the drought period.

  19. Early seedling development of Medicago truncatula genotypes ...

    African Journals Online (AJOL)

    adel

    2014-01-08

    Jan 8, 2014 ... germinated on filter papers imbibed in distilled water or in sodium .... Wards minimum variance method as a clustering algorithm. ... Mean values of plumule: radicle ratio of M. truncatula genotypes under different salt stress ...

  20. Seedling Lethal1, a Pentatricopeptide Repeat Protein Lacking an E/E+ or DYW Domain in Arabidopsis, Is Involved in Plastid Gene Expression and Early Chloroplast Development1[C][W

    Science.gov (United States)

    Pyo, Young Jae; Kwon, Kwang-Chul; Kim, Anna; Cho, Myeon Haeng

    2013-01-01

    Chloroplasts are the site of photosynthesis and the biosynthesis of essential metabolites, including amino acids, fatty acids, and secondary metabolites. It is known that many seedling-lethal mutants are impaired in chloroplast function or development, indicating the development of functional chloroplast is essential for plant growth and development. Here, we isolated a novel transfer DNA insertion mutant, dubbed sel1 (for seedling lethal1), that exhibited a pigment-defective and seedling-lethal phenotype with a disrupted pentatricopeptide repeat (PPR) gene. Sequence analysis revealed that SEL1 is a member of the PLS subgroup, which is lacking known E/E+ or DYW domains at the C terminus, in the PLS subfamily of the PPR protein family containing a putative N-terminal transit peptide and 14 putative PPR or PPR-like motifs. Confocal microscopic analysis showed that the SEL1-green fluorescent protein fusion protein is localized in chloroplasts. Transmission electron microscopic analysis revealed that the sel1 mutant is impaired in the etioplast, as well as in chloroplast development. In sel1 mutants, plastid-encoded proteins involved in photosynthesis were rarely detected due to the lack of the corresponding transcripts. Furthermore, transcript profiles of plastid genes revealed that, in sel1 mutants, the transcript levels of plastid-encoded RNA polymerase-dependent genes were greatly reduced, but those of nuclear-encoded RNA polymerase-dependent genes were increased or not changed. Additionally, the RNA editing of two editing sites of the acetyl-CoA carboxylase beta subunit gene transcripts in the sel1 mutant was compromised, though it is not directly connected with the sel1 mutant phenotype. Our results demonstrate that SEL1 is involved in the regulation of plastid gene expression required for normal chloroplast development. PMID:24144791

  1. Feasibility of Using the Optical Sensing Techniques for Early Detection of Huanglongbing in Citrus Seedlings

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    Alireza Pourreza

    2017-04-01

    Full Text Available A vision sensor was introduced and tested for early detection of citrus Huanglongbing (HLB. This disease is caused by the bacterium Candidatus Liberibacter asiaticus (CLas and is transmitted by the Asian citrus psyllid. HLB is a devastating disease that has exerted a significant impact on citrus yield and quality in Florida. Unfortunately, no cure has been reported for HLB. Starch accumulates in HLB infected leaf chloroplasts, which causes the mottled blotchy green pattern. Starch rotates the polarization plane of light. A polarized imaging technique was used to detect the polarization-rotation caused by the hyper-accumulation of starch as a pre-symptomatic indication of HLB in young seedlings. Citrus seedlings were grown in a room with controlled conditions and exposed to intensive feeding by CLas-positive psyllids for eight weeks. A quantitative polymerase chain reaction was employed to confirm the HLB status of samples. Two datasets were acquired; the first created one month after the exposer to psyllids and the second two months later. The results showed that, with relatively unsophisticated imaging equipment, four levels of HLB infections could be detected with accuracies of 72%–81%. As expected, increasing the time interval between psyllid exposure and imaging increased the development of symptoms and, accordingly, improved the detection accuracy.

  2. Xylem development and cell wall changes of soybean seedlings grown in space.

    Science.gov (United States)

    de Micco, Veronica; Aronne, Giovanna; Joseleau, Jean-Paul; Ruel, Katia

    2008-04-01

    Plants growing in altered gravity conditions encounter changes in vascular development and cell wall deposition. The aim of this study was to investigate xylem anatomy and arrangement of cellulose microfibrils in vessel walls of different organs of soybean seedlings grown in Space. Seeds germinated and seedlings grew for 5 d in Space during the Foton-M2 mission. The environmental conditions, other than gravity, of the ground control repeated those experienced in orbit. The seedlings developed in space were compared with those of the control test on the basis of numerous anatomical and ultrastructural parameters such as number of veins, size and shape of vessel lumens, thickness of cell walls and deposition of cellulose microfibrils. Observations made with light, fluorescence and transmission electron microscopy, together with the quantification of the structural features through digital image analysis, showed that the alterations due to microgravity do not occur at the same level in the various organs of soybean seedlings. The modifications induced by microgravity or by the indirect effect of space-flight conditions, became conspicuous only in developing vessels at the ultrastructural level. The results suggested that the orientation of microfibrils and their assembly in developing vessels are perturbed by microgravity at the beginning of wall deposition, while they are still able to orient and arrange in thicker and ordered structures at later stages of secondary wall deposition. The process of proper cell-wall building, although not prevented, is perturbed in Space at the early stage of development. This would explain the almost unaltered anatomy of mature structures, accompanied by a slower growth observed in seedlings grown in Space than on Earth.

  3. GERMINATION AND DEVELOPMENT OF BRACHIARIA SEEDLING IN TEXTURES OF SOIL AND SOWING DEPTH

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    J. H. Castaldo

    2016-09-01

    Full Text Available The agriculture expansion at Brazil is turning to lower clay index soils and consequently, less organic matter content and cation exchange capacity. To overcome those deficiencies, an intense organic matter addition in these soils may be a solution, and this solution is positive when using a crop-livestock integration with corn-pasture dual crop planted on winter. However, to establish this dual-crop system, there is a need to study the behavior of seeds and seedlings of Brachiaria ruziziensis sown in greater depths than normally recommended. Thus, this work aimed to determine the best depth of sowing B. ruziziensis in sandy and loamy soils of Umuarama region, studying the germination and early development of seedlings. The work was held in pots of 12 cm diameter x 12 cm deep, filled with 2 types of soil, a sandy and clay ones with 30 B. ruziziensis seeds sown each pot in five sowing depths: 0, 2, 4, 6 and 8 cm. After 16 days, the number of emerged seedlings was evaluated to set up the germination rate of each treatment, after that, the plants where leveled to 4 each pot, those were cultivated for another 45 days to evaluate the fresh and dried masses of plants and roots, the height of the plants and average length of roots. The sowing depth with higher percentage of germination estimated was 2.65 cm to sandy and 3.02 cm to clay soil. At seedlings development, there was a standard, with better development seedling at lower sowing depths on clay soil and better developments at higher sowing depths in sandy soil.

  4. Early development of grateloupia turuturu (Halymeniaceae, Rhodophyta)

    Science.gov (United States)

    Wang, Gaoge; Jiang, Chunmei; Wang, Shasha; Wei, Xiaojiao; Zhao, Fengjuan

    2012-03-01

    Grateloupia turuturu is a commercial red alga with potential value in nutraceuticals and pharmaceuticals. To supplement information on its life history and verify whether carpospores can be used for seedling culture, early development of G. turuturu was investigated under culture conditions (27°C, 10-13 μol/(m2·s) in irradiance, photoperiod 10:14 h L:D). Three physiological stages were recognized by continuous microscopic observation: division stage, discoid crust stage, and juvenile seedling stage. At the beginning of the division stage, the carpospores developed germ tubes into which the carpospore protoplasm was evacuated, and then the carpospore protoplasm in the germ tubes began to divide continuously until discoid crusts formed. Finally, upright thalli appeared on the discoid crusts and developed into juvenile seedlings. It took about 60 days for carpospores to develop into juvenile seedlings. The growth parameters, including germination rate for carpospores and discoid crust diameter, were recorded. These results contribute more information on the life cycle, and at the same time are of great significance in the scaling-up of artificial seedling cultures of G. turuturu.

  5. Effects of genetics, management intensity, and seedling density on early stocking in loblolly pine

    Science.gov (United States)

    Scott D. Roberts; Randall J. Rousseau; B. Landis Herrin

    2015-01-01

    Rapid establishment and early tree growth can be key factors in successful plantation management. This generally entails planting good quality planting stock at a seedling density appropriate for the management objectives and then managing at an appropriate intensity with a goal of fully occupying the site as quickly as possible within the context of those objectives....

  6. Accelerating Seed Germination and seedling development of Sorghum (Sorghum bicolor L. Moench) through hydro-priming

    Science.gov (United States)

    Dembele, S., Jr.

    2015-12-01

    Mali, a West Africa Sahelian country, is characterized by a strong dependence on rain-fed agriculture and a low adaptive capacity, making it one of the most vulnerable regions to climate change worldwide. Moreover, although with high uncertainties, most climate models used for the region recognize a growing uncertainty in the onset of the rainy season, which demands urgent adaptation measures. Early-season drought limits crops germination, and hence growth, and yield during rainfed depending production as is common now in Mali, West Africa. Crops germination and establishment could be improved by using seed priming, a process that dry seeds take up water to initiate the primary stages of germination, but the amount of water added is not enough for completing germination. The effects of hydro-priming (distilled, tap, rain, river and well water) were evaluated for three priming durations (4, 8 and 12 hour) in 2014 and 2015. Monitored were seed germination and seedling development of nine sorghum genotypes. Preliminary results showed that hydro-priming significantly improved germination rate, germination speed, number of seminal root, rate of survival and seedling vigour index, compared to non-primed seed treatments. However, seedling length, root length, shoot length and seedling dry weight did not differ significantly. Four out of the nine genotypes evaluated were attributed good seed quality and good response to hydro-priming. The priming with different sources of water resulted in higher seed germination (90%) and seedling development with well and river water, compared to the others. Seed germination rate, uniformity and speed were also enhanced by hydro-priming. It is argued that hydro-priming is a simple but effective method for improving seed germination and seedling development of sorghum. In addition hydro-priming is a safe, simple and inexpensive method to enhance germination. The most promising genotypes have consequently been included in consequent pot

  7. Gravimorphogenesis of Cucurbitaceae plants: development of peg cells and graviperception mechanism in cucumber seedlings.

    Science.gov (United States)

    Takahashi, H; Fujii, N; Kamada, M; Higashitani, A; Yamazaki, Y; Kobayashi, A; Takano, M; Yamasaki, S; Sakata, T; Mizuno, H; Kaneko, Y; Murata, T; Kamigaichi, S; Aizawa, S; Yoshizaki, I; Shimazu, T; Fukui, K

    2000-06-01

    We examined the effect of microgravity on the peg formation of cucumber seedlings for clarifying the mechanism of gravimorphogenesis in cucurbitaceous plants. The spaceflight experiments verified that gravity controls the formation of peg, hypocotyl hook and growth orientation of cucumber seedlings. Space-grown cucumber developed a peg on each side of the transition zone of the hypocotyl and root, indicating that on the ground peg formation is regulated negatively by gravity (Takahashi et al. 2000). It was found that the auxin-regulated gene, CS-IAA1, was strongly expressed in the transition zone where peg develops (Fujii et al. 2000). In the seedlings grown horizontally on the ground, CS-IAA1 transcripts were much abundant on the lower side of the transition zone, but no such differential expression of CS-IAA1 was observed in the space-grown cucumber (Kamada et al. 2000). These results imply that gravity plays a role in peg formation through auxin redistribution. By the negative control, peg formation on the upper side of the transition zone in the horizontally growing seedlings might be suppressed due to a reduction in auxin concentration. The threshold theory of auxin concentration accounted for the new concept, negative control of morphogenesis by gravity (Kamada et al. 2000). Anatomical studies have shown that there exists the target cells destined to be a peg and distinguishable at the early stage of the growth. Ultra-structural analysis suggested that endoplasmic reticulum develops well in the cells of the future peg. Furthermore, it was found that reorganization of cortical microtubules is required for the change in cell growth polarity in the process of peg formation. The spaceflight experiment with cucumber seedlings also suggested that in microgravity positive hydrotropic response of roots occurred without interference by gravitropic response (Takahashi et al. 1999b). Thus, this spaceflight experiment together with the ground-based studies has shown that

  8. [Effects of coat and sowing depth on seed germination and early seedling growth of Quercus wutaishanica].

    Science.gov (United States)

    Yan, Xing-Fui; Qiu, Zhi-Hu; Zhang, Qiang; Zhang, Kao-Wen; Zhou, Yun-Feng

    2014-01-01

    Under shade environment in glasshouse, the effects of seed coat and sowing depth (0, 2, 5, 10 or 15 cm) on seed germination and early seedling growth of Quercus wutaishanica were studied. Seed coat had obvious inhibiting effects on the germination of Q. wutaishanica seeds. The germination percentage of uncoated seeds increased significantly, averagely by 19.4% at different sowing depths. The germination index and vigor index were increased significantly and the germination was speeded in the peeling treatment. The germination percentages of uncoated and coated seeds were the highest at the sowing depth of 2 cm with 78.9% and 62.2%, respectively. The germination index and vigor index were the highest at the sowing depth of 2 cm, while the coefficient of rate of germination were the highest at the sowing depth of 5 cm. Leaf area per seedling and dry mass of seedlings increased significantly in the peeling treatment compared with those in the unpeeling treatment, but specific root length decreased significantly. The shoot height in the peeling and unpeeling treatments were the highest at the sowing depth of 5 cm with 13.8 and 14.2 cm, respectively. With the increasing of sowing depth, the basal stem diameter of seedlings increased, but tap-root length, number of lateral root and maximum of lateral root all decreased. Sowing depth had little influence on dry mass of seedlings.

  9. Development of cork oak (Quercus suber L.) seedlings in response to tree shelters and mulching in northwestern Tunisia

    Institute of Scientific and Technical Information of China (English)

    Taher Mechergui; Marta Pardos; Naceur Boussaidi; Brahim Hasnaoui; Douglass F.Jacobs

    2013-01-01

    The need for reforestation in cork oak (Quercus suber L.)areas is challenged by difficulties.Principal among these is herbivory of young plants,vegetative competition,and slow growth rates of cork oak seedlings.We evaluated the early development of cork oak seedlings treated using tree shelters and mulching in northwestern Tunisia.We tested three tree shelter treatments (non-vented,vented,and control) to shield seedlings from animal damage and five mulch types to control competing vegetation (Italian Stone Pine,Lentisk,combination of Italian Stone Pine and Lentisk (organic mulches),gravel (inorganic mulch) and no mulch).At the end of the two-year experiment,sheltered seedlings were 89-99% taller than unsheltered seedlings and had higher numbers and lengths of shoot growth flushes.In contrast,both stem diameter growth and dry weight biomass (from samples extracted after two years)were significantly reduced inside tree shelters.Root-to-shoot ratio was not significantly different in sheltered vs.unsheltered seedlings,suggesting that tree shelters do not adversely affect this parameter.Mulching alone did not favour growth,but could be beneficial when combined with tree shelters.The combination of vented tree shelters and gravel mulch was the most effective treatment for promoting diameter,height and stem volume growth.

  10. Early development of Chondrus ocellatus Holm (Gigartinaceae,Rhodophyta)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Chondrus is an economically important red algae widely used for food and biochemical purpose. It early development is crucial for the culture and seedling propagation. We chose tetraspores and carpospores of Chondrus ocellatus as examples for experiment of the culture, induction and release in laboratory condition, aiming to understand early development of C. ocellatus and to apply in seedling production. Mature C. ocellatus were collected in Qingdao, China, from Nov. to Dec. 2004. After the gametophyte and tetrasporophyte were brushed and washed with sterilized seawater, the algal materials were treated in 1.5% KI for 20 min, then were dried for 1 h to stimulate the releasing of spores. After the spores released overnight, it and recording under microscope were carried out. Continuous observation of the early development showed that both tetraspore and carpospore are similar to each other. In general, three stages of the early development were shown being division, discoid crust and seedling stages. To the division stage, the most obvious feature was the increasing of cell number; during the discoid crust stage, the discoid crust had a three-dimensional axis, and it began to differentiate into two types of cells: the basal cells and the apical cells; and to the seedling stage, several protuberances-like appeared on the discoid crusts and formed juvenile seedlings. Carpospores and tetraspores exhibited a similar development process that included division stage, discoid crust stage and seedling stage.

  11. Effect of Transplantation in Different Seedling Age on Growth and Yield of Spring Maize in Shanxi Early Mature Area

    Institute of Scientific and Technical Information of China (English)

    Cong ZHAO; Wei ZHANG; Yanlong HAN; Chunxia JIANG; Huatao LIU; Dongmei ZHANG; Mingjing HUANG; Xuefang HUANG; Enke LIU

    2016-01-01

    In order to explore a new mulch-free maize planting mode and the best seedling age for maize transplantation in Shanxi early mature area,a field experiment was carried out using completely randomized block design. Taking mulch based direct sowing as the control group,effects of transplantation in different seedling age on maize growing process,plant height,yield and composition factors of maize were analyzed.Results indicate that growing process of maize seedlings transplanted in different seedling age is slightly slower than the control group. Transplantation has the effect of reducing plant height. Although the yield of transplanted maize in different seedling age is lower than the control group. Besides,with the growth of seedling age of transplantation,the gap is widening. However,it is expected to realize mulch-free maize planting by transplantation in Shanxi early mature area. The yield of maize transplanted in two-leaf seedling age is not significantly different from the control group,and the yield is only 9% lower than the mulch-based direct sowing( CK). In conclusion,two-leaf period is the best seedling transplantation age for maize in Shanxi early mature area in this experiment condition.

  12. Research and Development of Statistical Analysis Software System of Maize Seedling Experiment

    Directory of Open Access Journals (Sweden)

    Hui Cao

    2014-03-01

    Full Text Available In this study, software engineer measures were used to develop a set of software system for maize seedling experiments statistics and analysis works. During development works, B/S structure software design method was used and a set of statistics indicators for maize seedling evaluation were established. The experiments results indicated that this set of software system could finish quality statistics and analysis for maize seedling very well. The development of this software system explored a new method for screening of maize seedlings.

  13. Influence of biostimulators on germination parameters and early growth of sunflower seedling

    Directory of Open Access Journals (Sweden)

    Miladinov Zlatica J.

    2015-01-01

    Full Text Available The aim of this paper was to examine the influence of biostimulators, with or without the use of fungicides, on seed quality parameters and early growth of sunflower seedling. Testing was conducted at the Institute of Field and Vegetable Crops in Novi Sad on cytoplasmic male sterile sunflower line HA-26-PR. The experiment included six treatments: Slavol S (25%, Slavol S (25% + fungicide (a.m. metalaxyl-M, Bioplant Flora (2%, Bioplant Flora (2% + fungicide (a.m. metalaxyl-M, Slavol S (25% + Bioplant Flora (2%, Slavol S (25% + Bioplant Flora (2% + fungicide (a. m. metalaxyl-M and control. Results of the research showed that treating the seed with biostimulators prior to sowing has a significant influence on seed germination parameters and early growth of sunflower seedling. The individual application of fertilizers, with or without the use of fungicide, gave a positive effect, while their combination led to a negative effect. The individual application of fertilizers, with or without combination with fungicide, may increase germination energy by 5%, germinability by 6%, but may also reduce the time of seed germination. Likewise, their use has a positive effect on early growth of sunflower seedling. [Projekat Ministarstva nauke Republike Srbije, br. TR 31025: Razvoj novih sorti i poboljšanja novih tehnologija proizvodnje uljanih biljnih vrsta za različite namene

  14. Development of an automatic visual grading system for grafting seedlings

    Directory of Open Access Journals (Sweden)

    Subo Tian

    2017-01-01

    Full Text Available In this study, a visual grading system of vegetable grafting machine was developed. The study described key technology of visual grading system of vegetable grafting machine. First, the contrasting experiment was conducted between acquired images under blue background light and natural light conditions, with the blue background light chosen as lighting source. The Visual C++ platform with open-source computer vision library (Open CV was used for the image processing. Subsequently, maximum frequency of total number of 0-valued pixels was predicted and used to extract the measurements of scion and rootstock stem diameters. Finally, the developed integrated visual grading system was experimented with 100 scions and rootstock seedlings. The results showed that success rate of grading reached up to 98%. This shows that selection and grading of scion and rootstock could be fully automated with this developed visual grading system. Hence, this technology would be greatly helpful for improving the grading accuracy and efficiency.

  15. Organ-coordinated response of early post-germination mahogany seedlings to drought.

    Science.gov (United States)

    Horta, Lívia P; Braga, Márcia R; Lemos-Filho, José P; Modolo, Luzia V

    2014-04-01

    Water deficit tolerance during post-germination stages is critical for seedling recruitment. In this work, we studied the effect of water deficit on morphological and biochemical responses in different organs of newly germinated mahogany (Swietenia macrophylla King) seedlings, a woody species that occurs in the Amazon rainforest. The root : shoot ratio increased under water deficit. The leaf number and water potential were not altered, although reductions in leaf area and stomatal conductance were observed. Osmotic potential became more negative in leaves of seedlings under severe stress. Water deficit increased fructose, glucose, sucrose and myo-inositol levels in leaves. Stems accumulated fructose, glucose and l-proline. Nitric oxide (NO) levels increased in the vascular cylinder of roots under severe stress while superoxide anion levels decreased due to augmented superoxide dismutase activity in this organ. Water deficit induced glutathione reductase activity in both roots and stems. Upon moderate or severe stress, catalase activity decreased in leaves and remained unaffected in the other seedling organs, allowing for an increase of hydrogen peroxide (H2O2) levels in leaves. Overall, the increase of signaling molecules in distinct organs-NO in roots, l-proline in stems and H2O2 and myo-inositol in leaves-contributed to the response of mahogany seedlings to water deficit by triggering biochemical processes that resulted in the attenuation of oxidative stress and the establishment of osmotic adjustment. Therefore, this body of evidence reveals that the development of newly germinated mahogany seedlings may occur in both natural habitats and crop fields even when water availability is greatly limited.

  16. Seed quality characteristics of Pinus halepensis – seed germination strategy and early seedling growth

    Directory of Open Access Journals (Sweden)

    T. K. Tsitsoni

    2009-12-01

    Full Text Available Pinus halepensis is a Mediterranean tree species occupying areas of high tourist interest, where it forms aesthetic and recreational forests. However, intense human pressure, adverse climatic conditions and overgrazing degrade Aleppo pine forest ecosystems and render the natural regeneration of this species difficult. The ecological, landscape, recreational and soil conservation uses of P. halepensis along with its aesthetic value, make this species important for landscape planning and multi-purpose forestry. For these reasons, artificial regeneration may be required in order to render ecosystem restoration faster. Although P. halepensis is characterized by a high germination capacity and a constant temperature of 20 °C is considered optimal for germination, no research has dealt with the germination behaviour and early growth of seedlings under alternative temperature conditions similar to those dominating outdoors. Moreover, little research was conducted on seed quality characteristics of this species. Thus, in this study seed quality of P. halepensis was estimated by measuring purity, number of seeds per kg, weight of 1000 seeds, average seed weight, seed moisture content and percentage of empty seeds. Also, seed germination capacity, germination rate, percentage of infected and not germinated viable seeds, abnormal seedlings as well as the total seedling length were studied under laboratory (alternative temperature and chamber (constant temperature conditions with the same photoperiod. Results showed that the percentage of empty seeds and abnormal seedlings was extremely low and the total germination percentage was very high (87–90% in both environments. Germination capacity, germination rate and the total length of seedlings did not show any differences among the two growth environments.

  17. Seed priming improves early seedling vigor, growth and productivity of spring maize

    Institute of Scientific and Technical Information of China (English)

    Hafeez ur Rehman; Hassan Iqbal; Shahzad M A Basra; Irfan Afzal; Muhammad Farooq; Abdul Wakeel; WANG Ning

    2015-01-01

    Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water (hydropriming), CaCl2 (2.2%, osmopriming), moringa leaf extracts (MLE 3.3%, osmopriming) and salicylic acid (SA, 50 mg L–1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in early planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyl contents fol owed by osmopriming with CaCl2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed priming;however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.

  18. Calcium Addition Affects Germination and Early Seedling Growth of Sweet Sorghum under Saline Conditions

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to determine the interactive effects of supple- mental Ca amendment and salinity on germination of sweet sorghum seeds in saline solution culture medium, and investigate the effects of different combinations of Na/Ca ratio in saline soils on the early growth of sweet sorghum plants. [Method] A germi- nation test and a greenhouse pot experiment were conducted to assess the interac- tive effects of calcium addition to culture medium on the germination and seedling growth of sweet sorghum (Sorghum saccharatum Moench) in saline soils with a range of NaYCa ratios. In the germination test, seeds were treated with different combinations of five calcium levels [0, 5, 10, 15, and 20 mmol/L Ca(NO3)2] and five salinity levels (0, 50, 100, 150, and 200 mmol/L NaCI). In the greenhouse experi- ment, seeds were sown in potting soils containing 3 salinity levels (2.3, 4.7 and 7.0 dS/m) and three Na:Ca ratios (10:0, 10:1, and 5:1). [Result] In the germination test, Ca addition at 5 mmol/L promoted germination by 5.5%, 9.9%, and 17.0% at the 3.4, 6.7 and 10.1 dS/m salinity levels. The higher Ca level (10 mmol/L) also in- creased germination by 9.1% and 7.8% at the 3.4 and 6.7 dS/m salinity levels. Then even higher Ca addition at 15 and 20 mmol/L appeared to promote germina- tion when culture media had high salinity (10.1 and 13.4 dS/m). In the greenhouse pot experiment, saline soil amended with supplemental Ca at the 2.3 and 4.7 dS/m salinity levels significantly promoted early seedling growth, with an increase of 6.8% to 28.2% in plant height and 14.3% to 67.9% in whole plant weight. From 28 to 42 d after seeding, the relative growth of seedling was increased by Ca addition, with a reduction of 49.5% to 66.0% in plant height and 4.8% to 61.9% in whole plant weight. From 42 to 56 d after seeding, however, the relative growth of seedling was significantly inhibited by Ca amendment. [Conclusion] Results of this study indicate that appropriate supplemental

  19. Magnetic treatment of irrigation water and snow pea and chickpea seeds enhances early growth and nutrient contents of seedlings.

    Science.gov (United States)

    Grewal, Harsharn S; Maheshwari, Basant L

    2011-01-01

    The effects of magnetic treatment of irrigation water and snow pea (Pisum sativum L var. macrocarpon) and Kabuli chickpea (Cicer arietinum L) seeds on the emergence, early growth and nutrient contents of seedlings were investigated under glasshouse conditions. The treatments included (i) magnetic treatment of irrigation water (MTW), (ii) magnetic treatment of seeds (MTS), (iii) magnetic treatment of irrigation water and seeds (MTWS) and (iv) no magnetic treatment of irrigation water or seeds as control treatment. A magnetic treatment device with two permanent magnets (magnetic induction: 3.5-136 mT) was used for the above treatments. Seeds were sown in washed sand and seedlings were harvested at 20 days. The results showed that MTW led to a significant (P < 0.05) increase in emergence rate index (ERI; 42% for snow pea and 51% for chickpea), shoot dry weight (25% for snow pea and 20% for chickpea) and contents of N, K, Ca, Mg, S, Na, Zn, Fe and Mn in both seedling varieties compared to control seedlings. Likewise, there were significant increases in ERI (33% for snow peas and 37% for chickpea), shoot dry weight (11% for snow pea and 4% for chickpea) and some nutrients of snow pea and chickpea seedlings with MTS in comparison with the controls. The results of this study suggest that both MTW and MTS have the potential to improve the early seedling growth and nutrient contents of seedlings.

  20. Seed priming improves early seedling vigor, growth and productivity of spring maize

    Institute of Scientific and Technical Information of China (English)

    Hafeez ur Rehman[1; Hassan lqbal[1; Shahzad M A Basra[1; Irfan Afzal[1; Muhammad Farooq[2; Abdul Wakeel[3; WANG Ning[4

    2015-01-01

    Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water (hydropriming), CaCI2 (2.2%, osmopriming), moringa leaf extracts (MLE 3.3%, osmopriming) and salicylic acid (SA, 50 mg L-1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in eady planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyll contents followed by osmopriming with CaCI2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed pdming; however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.

  1. Effect of apical meristem clipping on carbon allocation and morphological development of white oak seedlings

    Science.gov (United States)

    Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; Stanley J. Zarnoch

    1994-01-01

    Seedlings from three open-pollinated half-sib white oak seedlots were clipped in mid-July and their development was compared to nonclipped controls after one growing season.In general when data were analyzed by family, clipped seedlings were significantly less desirable in three to six of the eight variables tested.Numerically, in all families seedlots, the clipped...

  2. Optimum light transmittance for seed germination and early seedling recruitment of Pinus koraiensis: implications for natural regeneration

    Directory of Open Access Journals (Sweden)

    Zhang M

    2015-12-01

    Full Text Available Light transmittance regulated by canopy openness influences the microsite conditions for natural regeneration. The successful transition from seed germination to subsequent seedling recruitment (i.e., early seedling survival and growth determines the natural regeneration potential. However, there is little information on the effect of varying light transmittance on seed germination and seedling recruitment of Pinus koraiensis Siebold & Zucc. (Korean pine. We aimed to determine the optimum light requirements for this transition process in P. koraiensis to propose practical measures for improving its natural regeneration. The transition process was studied under five light transmittance regimes (100%, 60%, 30%, 15% and 5% of full light over two consecutive years (2010 and 2011. The highest germination percentage in both years occurred at 30% light transmittance. Generally, mean germination time (MGT declined with increased light transmittance. Seedling survival exhibited no significant differences between treatments for 1-year-old seedlings, but was higher at 30% than at 5% light transmittance for the 2-year-old seedlings. In contrast, seedling height, root collar diameter and total biomass were highest at 60%-100% light transmittance for both 1- and 2-year-old seedlings. Furthermore, the light transmittance also influenced the growth characteristics of P. koraiensis seedlings through regulating MGT. These results suggest that growth of P. koraiensis seedling requires a higher light transmittance (60%-100% than that required for seed germination, even though 30% light transmittance was favorable to the earlier emergence with larger specific leaf area. Silvicultural measures such as thinning are recommended to increase light irradiance in the forest understorey with the aim of improving the natural regeneration of P. koraiensis.

  3. Light Regulation of Gibberellins Metabolism in Seedling Development

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ying Zhao; Xu-Hong Yu; Xuan-Ming Liu; Chen-Tao Lin

    2007-01-01

    Light affects many aspects of plant development, including seed germination, stem elongation, and floral initiation. How photoreceptors control photomorphogenic processes is not yet fully understood. Because phytohormones are chemical regulators of plant development, it may not be surprising that light affects,directly or indirectly, cellular levels and signaling processes of various phytohormones, such as auxin,gibberellins (GA), cytokinin, ethylene, abscisic acid (ABA), and brassinosteroids (BR). Among those phytohormones, light regulation of GA metabolism has probably attracted more attention among photobiologists and it is arguably the most extensively studied plant hormone at present with respect to its role in photomorphogenesis. It has become increasingly clear that phytochromes and cryptochromes are the major photoreceptors mediating light regulation of GA homeostasis. This short article attempts to examine some recent developments in our understanding of how light and photoreceptors regulate GA biosynthesis and catabolism during seedling development. It is not our intention to carry out a comprehensive review of the field, and readers are referred to recent review articles for a more complete view of this area of study (Kamiya and Garcia-Martinez 1999; Hedden and Phillips 2000; Garcia-Martinez and Gil 2001; Olszewski et al. 2002; Halliday and Fankhauser 2003; Sun and Gubler 2004).

  4. Effects of imidacloprid and thiamethoxam as seed treatments on the early seedling characteristics and aphid-resistance of oilseed rape

    Institute of Scientific and Technical Information of China (English)

    HUANG Liang; ZHAO Chun-lin; HUANG Fang; BAI Run-e; L Yao-bin; YAN Feng-ming; HAO Zhong-ping

    2015-01-01

    Seed treatments with the neonicotinoid insecticides imidacloprid and thiamethoxam were evaluated to determine whether the chemicals at effective concentrations for aphid control would inlfuence the germination and early growth of oilseed rape,Brassica napus. Treatment with imidacloprid or thiamethoxam did not affect the cumulative germination rate, but signiifcantly inhibited establishment potential by suppressing root system development in the cotyledon stage. However, these alterations in seedling development in the thiamethoxam-treated seeds appeared not to be detrimental as leaves developed; in contrast, for the seedlings with imidacloprid as seed treatment agent, a signiifcantly decreased shoot/root ratio was stil evident at the late two-leaf stage. After two leaves developed, chlorophyl content per leaf in the thiamethoxam treatment was signiifcantly higher than that of the control, while chlorophyl content per leaf in the imidacloprid treatment remained close to that in the control. Most other parameters, i.e., height, leaf area, weight of stem, leaf or root, and other growth indexes, between the treatments and the control showed no signiifcant difference. Additionaly, it was found that storage time of the treated seeds had a signiifcant effect on cumulative germination rate. Treatment 30 d before planting signiifcantly reduced germination relative to that of the control. Al of the plants treated with neonicotinoids were shown to have signiifcant anti-aphid characteristics that persisted until the end of the trial.

  5. Early field performance of Acacia koa seedlings grown under subirrigation and overhead irrigation

    Science.gov (United States)

    Anthony S. Davis; Jeremiah R. Pinto; Douglass F. Jacobs

    2011-01-01

    Koa (Acacia koa A. Gray [Fabaceae]) seedlings were grown with subirrigation and overhead irrigation systems in an effort to characterize post-nursery field performance. One year following outplanting, we found no differences in seedling height or survival, but root-collar diameter was significantly larger for subirrigated seedlings. This indicates that koa seedlings,...

  6. Effect of Fertilization on the Morphological Development of European Hophormbeam (Ostrya carpinifolia Scop. Seedlings

    Directory of Open Access Journals (Sweden)

    Şemsettin Kulaç

    2016-10-01

    Full Text Available In this study, in order to help the mass production of seedlings, the effect of fertilization on the morphological development of hornbeam leafy European hophornbeam (Ostry carpinifolia Scop seedlings were investigated. For this, seedlings, which were obtained from the seeds coming from different European hophornbeam populations (Düzce-Yığılca, Antalya-Finike, Antalya-Akseki, Kastamonu-Şehdağ ve Adana-Saimbeyli from various parts of Turkey, were used. European hophornbeam seedlings were treated with different fertilizers, including urea, ammonium sulphate, compound fertilizer 15-15-15 and 20-20-0, and 6-9 months Osmocote release fertilizer, and effects of these fertilizers on the morphological characters were investigated. Fertilization contained the same amount of nitrogen, and was made in three different ways; (1 mixing with habitat, (2 topical application and (3 liquid application. The development of germinated European hophornbeam seeds, which were spring-sowed in the same medium were monitored during the vegetation period. At the end of vegetation period, seedlings were removed from the soil and morphological characteristics of root (seedling length, root collar diameter, root length, fresh root and stem weight of the seedlings, dried root and stem weight of the seedlings and bud number were measured. As a result, it was observed that fertilization positively affects the development of seedlings and depending on the fertilization type the seedlings of European hophornbeam populations were found to exhibit different improvements/growing. In addition, 6-9 months Osmocote release fertilizers were determined to be the best fertilizers affecting the morphological (diameter and height development of European hophornbeam populations effectively, and among the populations, Düzce and Kastamonu populations showed the best improvement/growing.

  7. Influence of lead on the development of lupin seedlings and ultrastructural localization of this metal in the roots

    Directory of Open Access Journals (Sweden)

    Adam Woźny

    2014-02-01

    Full Text Available The effect of lead on the early phases of development of yellow lupin seedlings was investigated. In the presence of this metal the number of germinating seeds was found to diminish distinctly, the hypocotyls and roots were shorter and the fresh weight and anthocyanin content in the cotyledones were markedly decreased. In the root cap cells lead was present in the vacuoles, ER, dictyosomes, the nuclear envelope and cell walls.

  8. Development of seedlings of watermelon cv. Crimson Sweet irrigated with biosaline water

    Directory of Open Access Journals (Sweden)

    José E. S. B. da Silva

    2015-09-01

    Full Text Available ABSTRACTThe limited access and the scarcity of good quality water for agriculture are some of the major problems faced in agricultural areas, particularly in arid and semiarid regions. The aim of this study was to evaluate the quality of watermelon seedlings (cv. Crimson Sweet, irrigated with different concentrations of biosaline water of fish culture. The experimental design was completely randomized with five treatments, corresponding to biosaline water at different concentrations (0, 33, 50, 67 and 100%, and four replicates of 108 seedlings. Watermelon seeds were sown in plastic trays filled with commercial substrate and irrigated with different solutions of biosaline water. Seedlings were harvested for biometric analysis at 14, 21 and 28 days after sowing. The use of biosaline water did not affect emergence and establishment of seedlings until 14 days after sowing, the period recommended for transplantation. However, the use of biosaline water affected the development of seedlings with longer exposure time.

  9. Development of a doorframe-typed swinging seedling pick-up device for automatic field transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Han, H.; Mao, H.; Hu, J.; Tian, K.

    2015-07-01

    A doorframe-typed swing seedling pick-up device for automatic field transplanters was developed and evaluated in a laboratory. The device, consisting of a path manipulator and two grippers, can move the pins slowly to extract seedlings from the tray cells and return quickly to the pick-up point for the next extraction. The path manipulator was constructed with the creative design of type-Ⅱ mechanism combination in series. It consists of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism. The gripper is a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction. The dynamic analysis of the designed seedling pick-up device was simulated with ADAMS software. Being the first prototype, various performance tests under local production conditions were conducted to find out the optimal machine operation parameters and transplant production conditions. As the gripper with multiple fine pins was moved by the swing pick-up device, it can effectively complete the transplanting work cycle of extracting, transferring, and discharging a seedling. The laboratory evaluation showed that the pick-up device equipped with two grippers can extract 80 seedlings/min with a 90% success and a 3% failure in discharging seedlings, using 42-day-old tomato plantlets. The quality of extracting seedlings was satisfactory. (Author)

  10. Development of a doorframe-typed swinging seedling pick-up device for automatic field transplantation

    Directory of Open Access Journals (Sweden)

    Han Luhua

    2015-06-01

    Full Text Available A doorframe-typed swing seedling pick-up device for automatic field transplanters was developed and evaluated in a laboratory. The device, consisting of a path manipulator and two grippers, can move the pins slowly to extract seedlings from the tray cells and return quickly to the pick-up point for the next extraction. The path manipulator was constructed with the creative design of type-II mechanism combination in series. It consists of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism. The gripper is a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction. The dynamic analysis of the designed seedling pick-up device was simulated with ADAMS software. Being the first prototype, various performance tests under local production conditions were conducted to find out the optimal machine operation parameters and transplant production conditions. As the gripper with multiple fine pins was moved by the swing pick-up device, it can effectively complete the transplanting work cycle of extracting, transferring, and discharging a seedling. The laboratory evaluation showed that the pick-up device equipped with two grippers can extract 80 seedlings/min with a 90% success and a 3% failure in discharging seedlings, using 42-day-old tomato plantlets. The quality of extracting seedlings was satisfactory.

  11. The window of desiccation tolerance shown by early-stage germinating seedlings remains open in the resurrection plant, Xerophyta viscosa.

    Directory of Open Access Journals (Sweden)

    Rafe Lyall

    Full Text Available Resurrection plants are renowned for their vegetative desiccation tolerance (DT. While DT in vegetative tissues is rare in angiosperms, it is ubiquitous in mature orthodox seeds. During germination, seedlings gradually lose DT until they pass a point of no return, after which they can no longer survive dehydration. Here we investigate whether seedlings of the resurrection plant Xerophyta viscosa ever lose the capacity to establish DT. Seedlings from different stages of germination were dehydrated for 48 hours and assessed for their ability to recover upon rehydration. While a transient decline in the ability of X. viscosa seedlings to survive dehydration was observed, at no point during germination was the ability to re-establish DT completely lost in all seedlings. Pre-treatment of seedlings with PEG or sucrose reduced this transient decline, and improved the survival rate at all stages of germination. Additionally, we observed that the trait of poikilochlorophylly (or loss of chlorophyll observed in adult X. viscosa leaves can be induced throughout seedling development. These results suggest that the window of DT seen in germinating orthodox seeds remains open in X. viscosa seedlings and that vegetative DT in Xerophyta species may have evolved from the ability to retain this program through to adulthood.

  12. The window of desiccation tolerance shown by early-stage germinating seedlings remains open in the resurrection plant, Xerophyta viscosa.

    Science.gov (United States)

    Lyall, Rafe; Ingle, Robert A; Illing, Nicola

    2014-01-01

    Resurrection plants are renowned for their vegetative desiccation tolerance (DT). While DT in vegetative tissues is rare in angiosperms, it is ubiquitous in mature orthodox seeds. During germination, seedlings gradually lose DT until they pass a point of no return, after which they can no longer survive dehydration. Here we investigate whether seedlings of the resurrection plant Xerophyta viscosa ever lose the capacity to establish DT. Seedlings from different stages of germination were dehydrated for 48 hours and assessed for their ability to recover upon rehydration. While a transient decline in the ability of X. viscosa seedlings to survive dehydration was observed, at no point during germination was the ability to re-establish DT completely lost in all seedlings. Pre-treatment of seedlings with PEG or sucrose reduced this transient decline, and improved the survival rate at all stages of germination. Additionally, we observed that the trait of poikilochlorophylly (or loss of chlorophyll) observed in adult X. viscosa leaves can be induced throughout seedling development. These results suggest that the window of DT seen in germinating orthodox seeds remains open in X. viscosa seedlings and that vegetative DT in Xerophyta species may have evolved from the ability to retain this program through to adulthood.

  13. Allelopathic Effects of Johnsongrass on Germination and Early Seedling Growth of Basil, Black Cumin, Cummin, Fennel, Isabgol and Psyllium

    Directory of Open Access Journals (Sweden)

    M Asgharipoor

    2012-12-01

    Full Text Available The allelopathic effect of weeds frequently inhibited the germination and seedling growth of crops. Johnsongrass (Sorghum halepens is known to contain water-soluble substances that are allelopathic. To identify the allelopathic effect of Johnsongrass, the effect of different aqueous extracts (0, 5, 10, 20, 30, 40 and 50 g L-1 obtained from roots and leaves of Johnsongrass on the seed germination and early seedling growth of some popular medicinal plants of Iran [basil (Ocimum basilicum, black cumin (Nigella sativa, cumin (Cuminum cyminum, fennel (Foeniculum vulgare, isabgol (Plantago ovate and psyllium (Plantago psyllium] were studied by bioassay. Both the root and leaf extracts of Johnsongrass in most cases inhibited the seed germination and early seedling growth of isabgol, psyllium, fennel and basil, while the seed germination and the early seedling growth of black cumin and cummin was simulated by both extracts at lower concentrations. However, this advantage was not found in higher concentrations, at which the extracts mostly had a negative effect on Nigella sativa and cumin. Leaf extracts was more effective to germination and early seedling growth than the root extract. The effectiveness of these extracts on the root growth was greater than that of the shoot growth of the test plants. The degree of sensitivity can be classified averaged across all extract concentrations in order of decreasing inhibition as follow: psyllium, isabgol, fennel, basil, black cumin and Cummin.

  14. HSPRO controls early Nicotiana attenuata seedling growth during interaction with the fungus Piriformospora indica.

    Science.gov (United States)

    Schuck, Stefan; Camehl, Iris; Gilardoni, Paola A; Oelmueller, Ralf; Baldwin, Ian T; Bonaventure, Gustavo

    2012-10-01

    In a previous study aimed at identifying regulators of Nicotiana attenuata responses against chewing insects, a 26-nucleotide tag matching the HSPRO (ORTHOLOG OF SUGAR BEET Hs1(pro)(-)(1)) gene was found to be strongly induced after simulated herbivory (Gilardoni et al., 2010). Here we characterized the function of HSPRO during biotic interactions in transgenic N. attenuata plants silenced in its expression (ir-hspro). In wild-type plants, HSPRO expression was not only induced during simulated herbivory but also when leaves were inoculated with Pseudomonas syringae pv tomato DC3000 and roots with the growth-promoting fungus Piriformospora indica. Reduced HSPRO expression did not affect the regulation of direct defenses against Manduca sexta herbivory or P. syringae pv tomato DC3000 infection rates. However, reduced HSPRO expression positively influenced early seedling growth during interaction with P. indica; fungus-colonized ir-hspro seedlings increased their fresh biomass by 30% compared with the wild type. Grafting experiments demonstrated that reduced HSPRO expression in roots was sufficient to induce differential growth promotion in both roots and shoots. This effect was accompanied by changes in the expression of 417 genes in colonized roots, most of which were metabolic genes. The lack of major differences in the metabolic profiles of ir-hspro and wild-type colonized roots (as analyzed by liquid chromatography time-of-flight mass spectrometry) suggested that accelerated metabolic rates were involved. We conclude that HSPRO participates in a whole-plant change in growth physiology when seedlings interact with P. indica.

  15. Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest

    Science.gov (United States)

    Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

    2016-11-01

    Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities.

  16. Reduced Triacylglycerol Mobilization during Seed Germination and Early Seedling Growth in Arabidopsis Containing Nutritionally Important Polyunsaturated Fatty Acids

    Science.gov (United States)

    Shrestha, Pushkar; Callahan, Damien L.; Singh, Surinder P.; Petrie, James R.; Zhou, Xue-Rong

    2016-01-01

    There are now several examples of plant species engineered to synthesize and accumulate nutritionally important polyunsaturated fatty acids in their seed triacylglycerols (TAG). The utilization of TAG in germinating seeds of such transgenic plants was unknown. In this study, we examined the TAG utilization efficiency during seed germination in transgenic Arabidopsis seeds containing several examples of these fatty acids. Seed TAG species with native fatty acids had higher utilization rate than the TAG species containing transgenically produced polyunsaturated fatty acids. Conversely, quantification of the fatty acid components remaining in the total TAG after early stages of seed germination revealed that the undigested TAGs tended to contain elevated levels of the engineered polyunsaturated fatty acids (PUFA). LC-MS analysis further revealed asymmetrical mobilization rates for the individual TAG species. TAGs which contained multiple PUFA fatty acids were mobilized slower than the species containing single PUFA. The mobilized engineered fatty acids were used in de novo membrane lipid synthesis during seedling development.

  17. Agroforestry wastes used for germination and development of sweet angelim seedlings

    Directory of Open Access Journals (Sweden)

    João Ricardo Avelino Leão

    2013-03-01

    Full Text Available This paper aimed to define the ideal type of agroforestry substrate and the adequate depth of sweet angelim sowing, providing information on the development of seedlings, as well as on low-cost substrates which are easy to be obtained. An experiment in a greenhouse was carried out, in a completely randomized design with treatments distributed in a factorial scheme (5x3, with the factors agroforestry substrates and depths being replicated seven times with a seed in each container. The following parameters were analyzed: germination percentage, germination speed index, total dry weight, number of leaves, seedlings height and coll diameter, and Dickson’s seedling quality index. The results showed that the most suitable substrate for germination and development of this native species was that containing Brazil nut shell, peanut hull, or açai seed, and the ideal depth for sowing and managing seedlings was on the surface.

  18. In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

    Directory of Open Access Journals (Sweden)

    Stojičić Dragana

    2012-01-01

    Full Text Available This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.

  19. Early Developments, 2002.

    Science.gov (United States)

    Winton, Pam, Ed.; Buysse, Virginia, Ed.

    2002-01-01

    This document consists of the three 2002 issues of a journal reporting new research in early child development conducted by the Frank Porter Graham Child Development Center (FPG) at the University of North Carolina at Chapel Hill. Articles in the Winter 2002 issue highlight some current work at FPG on factors that enhance or inhibit social and…

  20. Arbuscular Mycorrhizal Fungi and Biochar Improved Early Growth of Neem (Melia azedarach Linn. Seedling Under Greenhouse Conditions

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    Sri Wilarso Budi

    2013-08-01

    Full Text Available The objective of this research was to determine the effect of biochar on the seedling quality index and growth of neem tree seedlings and arbuscular mycorrhizal fungi (AMF development  grown on ultisol  soil medium.  Two factors in completely randomised experimental design was conducted under green house conditions and Duncan Multiple Range Test was used to analyse the data. The results showed that neem seedling quality index was improved by interaction of AMF fungi and biochar amandment. The growth of neem seedling was significantly increased by interactions of arbuscular mycorrhizal fungi and biochar.  The combination  treatment of Glomus etunicatum and biochar 10% gave best results of height and diameter, and significantly increased by 712% and 303% respectively, as compared to control plant, while the combination treatment of Gigaspora margarita and biochar 10% gave the best result of shoot dry weight, and root dry weight and significantly increase by 4,547% and 6,957% as compared to control plant.  The mycorrhizal root colonization was increased with increasing biochar added, but decreases when 15% of biochar was applied.  N, P, and K uptake of 12 weeks neem seedling old was higher and significantly increased as compared to control plant.Keywords: AMF development, nutrient uptake , plant growth , seedling quality index, biochar  DOI: 10.7226/jtfm.19.2.103

  1. Effect and Mechanism of Cold Tolerant Seed-Coating Agents on the Cold Tolerance of Early Indica Rice Seedlings

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hai-qing; ZOU Ying-bin; XIAO Guo-chao; XIONG Yuan-fu

    2007-01-01

    To better understand the effect and mechanism of cold tolerant seed-coating agents on the cold tolerance of rice seedlings,the physiological and biochemical effects of four cold tolerant seed-coating agents (HET, YKJ, YKZYJ, and the ABA seed coating agents) on two early indica rice varieties were studied under chilling stress. The results showed that the rice seedlings treated with cold tolerant seed-coating agents under chilling stress maintained dramatically higher root vigor,POD, CAT and SOD activities, and chlorophyll content, had lower MDA content and electrolyte leakage, and accumulated more soluble sugar and free proline, when compared with the control without the treatment, and finally showed lower plant injury rate. It was indicated that the cold tolerant seed coating agent improved the ability of rice seedlings in resisting to chilling stress. YKZYJ was ranked the first in terms of the efficiency in cold tolerance among the four cold tolerant seed-coating agents tested.

  2. Ammonia Volatilization from Urea-Application Influenced Germination and Early Seedling Growth of Dry Direct-Seeded Rice

    Directory of Open Access Journals (Sweden)

    Xiaoli Qi

    2012-01-01

    Full Text Available Poor seed germination and early seedling growth associated with urea-induced soil ammonia volatilization are major constraints in the adoption of dry direct-seeded rice. To directly examine soil ammonia volatilization and its damage to seed germination and early seedling growth of dry direct-seeded rice when urea is applied at seeding, two Petri-dish incubation experiments and a field experiment were conducted. Ammonia volatilization due to urea application significantly reduced seed germination and early seedling growth of dry direct-seedling rice. NBPT significantly reduced ammonia volatilization following urea application. The application of ammonium sulfate, instead of urea at seeding, may mitigate poor crop establishment of dry direct-seeded rice. Root growth of dry direct-seeded rice was more seriously inhibited by soil ammonia volatilization than that of shoot. Results suggest that roots are more sensitive to soil ammonia toxicity than shoots in dry direct-seeded rice system when N is applied as urea at seeding.

  3. Effects of aluminum on growth, development, and nutrient composition of honeylocust (Gleditsia triacanthos L.) seedlings.

    Science.gov (United States)

    Thornton, F. C.; Schaedle, M.; Raynal, D. J.

    1986-12-01

    Hydroponic experiments were conducted to determine the effects of aluminum (Al) on root development, shoot morphology and the nutrient composition of honeylocust seedlings (Gleditsia triacanthos L.). Seedlings were grown at pH 4 in a nutrient solution containing 0, 50, 150, 600 or 1500 microM Al. Within seven days, there were significant differences in root growth and root nutrient composition between control seedlings and seedlings grown in the presence of 150 or 600 microM Al. By day 14, significant reductions in leaf production and plant height were observed in seedlings treated with 1500 microM Al. At the lowest Al concentration, 50 microM, leaf size and expansion rates were significantly lower than in the controls. By the third week of the experiment, Ca and Mg concentrations in young leaves of the Al-treated seedlings were significantly lower than in leaves of control plants. Analysis of old leaf tissue, however, revealed no consistent pattern of nutrient concentration with Al treatment.

  4. Changes in low-molecular-weight thiol-disulphide redox couples are part of bread wheat seed germination and early seedling growth.

    Science.gov (United States)

    Gerna, Davide; Roach, Thomas; Stöggl, Wolfgang; Wagner, Johanna; Vaccino, Patrizia; Limonta, Margherita; Kranner, Ilse

    2017-06-01

    The tripeptide antioxidant glutathione (γ-l-glutamyl-l-cysteinyl-glycine; GSH) essentially contributes to thiol-disulphide conversions, which are involved in the control of seed development, germination, and seedling establishment. However, the relative contribution of GSH metabolism in different seed structures is not fully understood. We studied the GSH/glutathione disulphide (GSSG) redox couple and associated low-molecular-weight (LMW) thiols and disulphides related to GSH metabolism in bread wheat (Triticum aestivum L.) seeds, focussing on redox changes in the embryo and endosperm during germination. In dry seeds, GSH was the predominant LMW thiol and, 15 h after the onset of imbibition, embryos of non-germinated seeds contained 12 times more LMW thiols than the endosperm. In germinated seeds, the embryo contained 17 and 11 times more LMW thiols than the endosperm after 15 and 48 h, respectively. This resulted in the embryo having significantly more reducing half-cell reduction potentials of GSH/GSSG and cysteine (Cys)/cystine (CySS) redox couples (EGSSG/2GSH and ECySS/2Cys, respectively). Upon seed germination and early seedling growth, Cys and CySS concentrations significantly increased in both embryo and endosperm, progressively contributing to the cellular LMW thiol-disulphide redox environment (Ethiol-disulphide). The changes in ECySS/2Cys could be related to the mobilisation of storage proteins in the endosperm during early seedling growth. We suggest that EGSSG/2GSH and ECySS/2Cys can be used as markers of the physiological and developmental stage of embryo and endosperm. We also present a model of interaction between LMW thiols and disulphides with hydrogen peroxide (H2O2) in redox regulation of bread wheat germination and early seedling growth.

  5. Water availability influences morphology, mycorrhizal associations, PSII efficiency and polyamine metabolism at early growth phase of Scots pine seedlings.

    Science.gov (United States)

    Muilu-Mäkelä, Riina; Vuosku, Jaana; Läärä, Esa; Saarinen, Markku; Heiskanen, Juha; Häggman, Hely; Sarjala, Tytti

    2015-03-01

    Scots pine (Pinus sylvestris L.) is adapted to various soil types with diverse water availabilities. However, Scots pine seedlings are vulnerable to abiotic stress during the early growth, when they may be exposed to both dry and wet conditions. Here, we focused on the above and below ground coping strategies of Scots pine seedlings under controlled wet, optimal and dry soil conditions by investigating morphological traits including seedling biomass, number of root tips, proportion of mycorrhizal root tips and brown needles. In addition, we studied metabolic and physiological responses including gene expression involved in biosynthesis and catabolism of polyamines (PA), PSII efficiency and the expression of the catalase (CAT) late-embryogenesis abundant protein (LEA), pyruvate decarboxylase (PDC), glutamate-cysteine ligase (GCL) and glutathione synthetase (GS) genes. We found that seedlings invested in shoots by maintaining stable shoot water content and high PSII efficiency under drought stress. Free and soluble conjugated putrescine (Put) accumulated in needles under drought stress, suggesting the role of Put in protection of photosynthesizing tissues. However, the expression of the PA biosynthesis genes, arginine decarboxylase (ADC), spermidine synthase (SPDS) and thermospermine synthase (ACL5) was not affected under drought stress whereas catabolizing genes diamino oxidase (DAO) and polyamine oxidase (PAO) were down-regulated in shoots. The morphology of the roots was affected by peat water content. Furthermore, both drought stress and water excess restricted the seedling ability to sustain a symbiotic relationship. The consistent pattern of endogenous PAs seems to be advantageous to the Scots pine seedlings also under stress conditions.

  6. Gibberellin mediates the development of gelatinous fibres in the tension wood of inclined Acacia mangium seedlings.

    Science.gov (United States)

    Nugroho, Widyanto Dwi; Nakaba, Satoshi; Yamagishi, Yusuke; Begum, Shahanara; Marsoem, Sri Nugroho; Ko, Jae-Heung; Jin, Hyun-O; Funada, Ryo

    2013-11-01

    Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus. Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems. Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells. The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism.

  7. Reassessment of an Arabidopsis cell wall invertase inhibitor AtCIF1 reveals its role in seed germination and early seedling growth.

    Science.gov (United States)

    Su, Tao; Wolf, Sebastian; Han, Mei; Zhao, Hongbo; Wei, Hongbin; Greiner, Steffen; Rausch, Thomas

    2016-01-01

    In higher plants, cell wall invertase (CWI) and vacuolar invertase (VI) are recognized as essential players in sugar metabolism and sugar signaling, thereby affecting source-sink interactions, plant development and responses to environmental cues. CWI and VI expression levels are transcriptionally controlled; however, both enzymes are also subject to posttranslational control by invertase inhibitor proteins. The physiological significances of inhibitor proteins during seed germination and early seedling development are not yet fully understood. Here, we demonstrate that the inhibitor isoform AtCIF1 impacted on seed germination and early seedling growth in Arabidopsis. The primary target of AtCIF1 was shown to be localized to the apoplast after expressing an AtCIF1 YFP-fusion construct in tobacco epidermis and transgenic Arabidopsis root. The analysis of expression patterns showed that AtCWI1 was co-expressed spatiotemporally with AtCIF1 within the early germinating seeds. Seed germination was observed to be accelerated independently of exogenous abscisic acid (ABA) in the AtCIF1 loss-of-function mutant cif1-1. This effect coincided with a drastic increase of CWI activity in cif1-1 mutant seeds by 24 h after the onset of germination, both in vitro and in planta. Accordingly, quantification of sugar content showed that hexose levels were significantly boosted in germinating seeds of the cif1-1 mutant. Further investigation of AtCIF1 overexpressors in Arabidopsis revealed a markedly suppressed CWI activity as well as delayed seed germination. Thus, we conclude that the posttranslational modulation of CWI activity by AtCIF1 helps to orchestrate seed germination and early seedling growth via fine-tuning sucrose hydrolysis and, possibly, sugar signaling.

  8. Mucilage extraction and substrates in the seedling development of yellow passion fruit plants

    Directory of Open Access Journals (Sweden)

    Ricardo Sfeir Aguiar

    2014-02-01

    Full Text Available The object of this work was to evaluate different methods of mucilage extraction and substrates on passion fruit seedling emergence and development , in a mist chamber. Five methods of mucilage extraction were used: water, water + sand, water + virgin whitewash; blender with protected blades and fermentation in water, and three different types of substrates: rice hull, vermiculite and coconut fiber. The experiment had a completely randomized design with five replications in a factorial 5 x 3 scheme (5 extraction methods of seed mucilage and 3 substrates being each parcel composed of 25 seeds. The parameters evaluated were: seedling emergence, speed of emergence index, leaf number, stem length, longest root length, weight of dry matter of roots and shoots. Water and fermentation in water are the best method for mucilage extraction and rice hull and coconut fiber are the best substrate for passionfruit seedling emergence and development.

  9. Germination and Seedling Development of Seeds from Different Parkia biglobosa (Jacq G. Don Trees

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    Christiana O. ADEYEMI

    2013-02-01

    Full Text Available The effect of daylight, continuous illumination and acid scarification on the seed germination and seedling vegetative growth (epicotyl and hypocotyl lengths, and number of secondary roots of different Parkia biglobosawere investigated in the Plant Physiology Laboratory University of Ilorin, Ilorin Kwara State Nigeria. Seeds from two out of the twenty six Parkia tree samples (trees B and T germinated within 24 hours of planting in the daylight germination study while seeds from another tree (Q did not germinate until the third week after planting (3WAP. Some seeds have higher germination percentage both in the daylight (preliminary germination study and in the continuous light (illuminated study. The treatment with concentrated Sulphric acid (conc. H2SO4was effective in breaking the seed dormancy as seeds from eight (8 trees produced one hundred percent (100% germination. At p= 0.05 the length of epicotyl and hypocoty1 lengths were significantly different as seedling vegetative growth were long in the seedlings from the daylight experiment than the continuous light experiment. The vegetative growths of the seedlings from the scarified seed were longer at 15min of scarification in all except in trees F and Z. It was observed that the time of scarification affect the both seed germination and seedling development.

  10. Seedling development and evaluation of genetic stability of cryopreserved Dendrobium hybrid mature seeds.

    Science.gov (United States)

    Galdiano, Renato Fernandes; de Macedo Lemos, Eliana Gertrudes; de Faria, Ricardo Tadeu; Vendrame, Wagner Aparecido

    2014-03-01

    Vitrification, a simple, fast, and recommended cryopreservation method for orchid germplasm conservation, was evaluated for Dendrobium hybrid "Dong Yai" mature seeds. The genetic stability of regenerated seedlings was also evaluated using flow cytometry. Mature seeds from this hybrid were submitted to plant vitrification solution (PVS2) for 0, 0.5, 1, 2, 3, 4, 5, or 6 h at 0 °C. Subsequently, they were plunged into liquid nitrogen (LN) at -196 °C for 1 h and recovered in half-strength Murashige and Skoog culture medium (1/2 MS), and seed germination was evaluated after 30 days. Seeds directly submitted to LN did not germinate after cryopreservation. Seeds treated with PVS2 between 1 and 3 h presented the best germination (between 51 and 58%), although longer exposure to PVS2 returned moderated germination (39%). Germinated seeds were further subcultured in P-723 culture medium and developed whole seedlings in vitro after 180 days, with no abnormal characteristics, diseases, or nutritional deficiencies. Seedlings were successfully acclimatized under greenhouse conditions with over 80% survival. Flow cytometry analysis revealed no chromosomal changes on vitrified seedlings, as well as seedlings germinated from the control treatment (direct exposure to LN). These findings indicate that vitrification is a feasible and safe germplasm cryopreservation method for commercial Dendrobium orchid hybrid conservation.

  11. Plant species differ in early seedling growth and tissue nutrient responses to arbuscular and ectomycorrhizal fungi.

    Science.gov (United States)

    Holste, Ellen K; Kobe, Richard K; Gehring, Catherine A

    2017-04-01

    Experiments with plant species that can host both arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) are important to separating the roles of fungal type and plant species and understanding the influence of the types of symbioses on plant growth and nutrient acquisition. We examined the effects of mycorrhizal fungal type on the growth and tissue nutrient content of two tree species (Eucalyptus grandis and Quercus costaricensis) grown under four nutrient treatments (combinations of low versus high nitrogen (N) and phosphorus (P) with different N:P ratios) in the greenhouse. Trees were inoculated with unidentified field mixtures of AMF or EMF species cultivated on root fragments of AMF- or EMF-specific bait plants. In E. grandis, inoculation with both AMF and EMF positively affected belowground plant dry weight and negatively affected aboveground dry weight, while only inoculation with AMF increased tissue nutrient content. Conversely, Q. costaricensis dry weight and nutrient content did not differ significantly among inoculation treatments, potentially due to its dependence on cotyledon reserves for growth. Mineral nutrition of both tree species differed with the ratio of N to P applied while growth did not. Our results demonstrate that both tree species' characteristics and the soil nutrient environment can affect how AMF and EMF interact with their host plants. This research highlights the importance of mycorrhizal fungal-tree-soil interactions during early seedling growth and suggests that differences between AMF and EMF associations may be crucial to understanding forest ecosystem functioning.

  12. Asymbiotic germination, seedling development and plantlet propagation of Encyclia aff. oncidioides - an endangered orchid

    Directory of Open Access Journals (Sweden)

    Ewa Łojkowska

    2011-01-01

    Full Text Available In order to estimate the best germination conditions of Encyclia aff. oncidioides seeds, five different media (Fast, Knudson C modified by Vajrabhaya, Murashige and Skoog, PB2 and modified Vacin and Went with different concentrations of plant growth regulators such as benzyladenine (BA, naphthaleneacetic acid (NAA and gibberellic acid (GA3 were tested. No beneficial effect was observed when BA and NAA were applied to the germination medium and GA3 inhibited germination. The effect of light, activated charcoal, coconut water and casein hydrolysate on seed germination was also studied. The growth rate of seedlings on three different media supplemented with activated charcoal and plant growth regulators was checked. The applied plant growth regulators had no beneficial effect on the further growth of seedlings. Fast and PB2 media with 0.2% activated charcoal proved to be the best for E. aff. oncidioides seed germination, seedling development and plantlet propagation.

  13. Mapping of quantitative trait locus (QTLs that contribute to germination and early seedling drought tolerance in the interspecific cross Setaria italica×Setaria viridis.

    Directory of Open Access Journals (Sweden)

    Lufeng Qie

    Full Text Available Drought tolerance is an important breeding target for enhancing the yields of grain crop species in arid and semi-arid regions of the world. Two species of Setaria, domesticated foxtail millet (S. italica and its wild ancestor green foxtail (S. viridis are becoming widely adopted as models for functional genomics studies in the Panicoid grasses. In this study, the genomic regions controlling germination and early seedling drought tolerance in Setaria were identified using 190 F7 lines derived from a cross between Yugu1, a S. italica cultivar developed in China, and a wild S. viridis genotype collected from Uzbekistan. Quantitative trait loci were identified which contribute to a number of traits including promptness index, radical root length, coleoptile length and lateral root number at germinating stage and seedling survival rate was characterized by the ability of desiccated seedlings to revive after rehydration. A genetic map with 128 SSR markers which spans 1293.9 cM with an average of 14 markers per linkage group of the 9 linkage groups was constructed. A total of eighteen QTLs were detected which included nine that explained over 10% of the phenotypic variance for a given trait. Both the wild green foxtail genotype and the foxtail millet cultivar contributed the favorite alleles for traits detected in this trial, indicating that wild Setaria viridis populations may serve as a reservoir for novel stress tolerance alleles which could be employed in foxtail millet breeding.

  14. Comparative seed germination and seedling development of the ghost orchid, Dendrophylax lindenii (Orchidaceae), and molecular identification of its mycorrhizal fungus from South Florida

    Science.gov (United States)

    Hoang, Nguyen H.; Kane, Michael E.; Radcliffe, Ellen N.; Zettler, Lawrence W.; Richardson, Larry W.

    2017-01-01

    Background and Aims The endangered leafless ghost orchid, Dendrophylax lindenii, one of the most renowned orchids in the world, is difficult to grow under artificial conditions. Published information on asymbiotic and symbiotic (co-culture with a mycobiont) seed germination, seedling anatomy and developmental morphology of this leafless orchid is completely lacking. This information is critical for the development of efficient procedures for ghost orchid production for successful reintroduction. Methods Ghost orchid seedling early development stages were morphologically and anatomically defined to compare germination, embryo and protocorm maturation and seedling development during asymbiotic and symbiotic culture with one of two mycorrhizal strains (Dlin-379 and Dlin-394) isolated from ghost orchid roots in situ. Key Results Seeds symbiotically germinated at higher rates when cultured with fungal strain Dlin-394 than with strain Dlin-379 or asymbiotically on P723 medium during a 10-week culture period. Fungal pelotons were observed in protocorm cells co-cultured with strain Dlin-394 but not Dlin-379. Some 2-year-old seedlings produced multinode inflorescences in vitro. Production of keikis from inflorescence nodes indicated the capacity for clonal production in the ghost orchid. Conclusions Ghost orchid embryo and seedling development were characterized into seven stages. Fungal strain Dlin-394 was confirmed as a possible ghost orchid germination mycobiont, which significantly promoted seed germination and seedling development. Internal transcribed spacer sequencing data confirmed that Dlin-394 belongs within the genus Ceratobasidium. These results offer the opportunity to examine the benefits of using a mycobiont to enhance in vitro germination and possibly ex vitro acclimatization and sustainability following outplanting. PMID:28025292

  15. Effect of acorn size on development of northern red oak 1-0 seedlings

    Science.gov (United States)

    Paul P. Kormanik; Shi-Jean S. Sung; T.L. Kormanik; S.E. Schlarbaum; Stanley J. Zarnoch

    1998-01-01

    The effect of acorn size on seedling development was determined for 20 northern red oak (Quercus rubra L.) mother tree selections from the USDA Forest Service's Eastern Tennessee Watauga seed orchard. Acorns from each mother tree were visually separated into three size groups, weighed, and sown separately in forest nurseries located in Georgia,...

  16. Trichloroacetate, an inhibitor of wax biosynthesis, prevents the development of hyperhydricity in Arabidopsis seedlings

    NARCIS (Netherlands)

    Klerk, de Geert Jan; Pramanik, Dewi

    2017-01-01

    Arabidopsis seedlings developed severe hyperhydricity (HH) when 0.2% Gelrite was used to solidify the medium instead of 0.7% agar. One mM trichloroacetate (TCA, an inhibitor of wax synthesis) strongly reduced the amount of wax. TCA also strongly increased the permeability of leaves for water as show

  17. The role of population origin and microenvironment in seedling emergence and early survival in Mediterranean maritime pine (Pinus pinaster Aiton.

    Directory of Open Access Journals (Sweden)

    Natalia Vizcaíno-Palomar

    Full Text Available Understanding tree recruitment is needed to forecast future forest distribution. Many studies have reported the relevant ecological factors that affect recruitment success in trees, but the potential for genetic-based differences in recruitment has often been neglected. In this study, we established a semi-natural reciprocal sowing experiment to test for local adaptation and microenvironment effects (evaluated here by canopy cover in the emergence and early survival of maritime pine (Pinus pinaster Aiton, an emblematic Mediterranean forest tree. A novel application of molecular markers was also developed to test for family selection and, thus, for potential genetic change over generations. Overall, we did not find evidence to support local adaptation at the recruitment stage in our semi-natural experiment. Moreover, only weak family selection (if any was found, suggesting that in stressful environments with low survival, stochastic processes and among-year climate variability may drive recruitment. Nevertheless, our study revealed that, at early stages of recruitment, microenvironments may favor the population with the best adapted life strategy, irrespectively of its (local or non-local origin. We also found that emergence time is a key factor for seedling survival in stressful Mediterranean environments. Our study highlights the complexity of the factors influencing the early stages of establishment of maritime pine and provides insights into possible management actions aimed at environmental change impact mitigation. In particular, we found that the high stochasticity of the recruitment process in stressful environments and the differences in population-specific adaptive strategies may difficult assisted migration schemes.

  18. Impact of climate change, seedling type and provenance on the risk of damage to Norway spruce (Picea abies (L.) Karst.) seedlings in Sweden due to early summer frosts

    Energy Technology Data Exchange (ETDEWEB)

    Langvall, Ola (Swedish Univ. of Agricultural Sciences, Unit for Field-based Forest Research, Asa Forest Research Station, Lammhult (Sweden))

    2011-04-15

    A model including site-specific microclimate-affecting properties of a forest regeneration area together with seedling characteristics was used to evaluate the accumulated risk of frost damage to Norway spruce (Picea abies (L.) Karst.) seedlings. Climate change in Sweden was simulated on the basis of the regional climate model RCA3. The daily average temperature, the driving factor for bud burst in the model, was adjusted using the difference between the mean of the climate model data for the years 1961-1990 and 2036-2065. The model was run for a highly frost prone, clear-cut site in which bare-rooted Norway spruce seedlings of mid-Swedish provenance were planted. Alternate runs were conducted with data for containerized seedlings and seedlings of Belarusian origin. The study showed that bud burst will occur at earlier dates throughout Sweden in the period 2036-2065 if the climate changes according to either of the climate scenarios examined, compared to the reference period 1961-1990. Furthermore, the risk of damage to Norway spruce seedlings as a result of frost events during summer will increase in southern Sweden and be unaffected or decrease in northern Sweden. The risk of frost damage was exacerbated in containerized seedlings, while the risk was lower for the seedlings of Belarusian provenance when compared with bare-rooted seedlings or seedlings of mid-Swedish origin

  19. EVALUATION FOR THE EFFICIENCY OF EARLY SELECTION IN Acacia mangium SEEDLING SEED ORCHARDS BASED ON AGE TRENDS IN GENETIC PARAMETER

    Directory of Open Access Journals (Sweden)

    Arif Nirsatmanto

    2012-07-01

    Full Text Available The efficiency of early selection was evaluated based on age trend in genetic parameters using tree height data that was measured periodically repeatedly up to age 3 years of age in four seedling seed orchards of Acacia mangium at South Kalimantan, Indonesia. The four orchards were grouped into two populations based upon their provenances, namely: Papua New Guinea (PNG and Far North Queensland-Australia (FNQ. A model for time trend of genetic parameters was developed by fitting regression equation to the estimates of variances and correlations using tree height data as an independent variable. In both populations, genetic variances and total phenotypic variances increased along with the mean height. Trend of individual heritability along the rotation ages were almost stable at around 0.19 for PNG, and gradually increased from 0.36 to 0.40 for FNQ. Trend of genetic correlations between selection age and rotation age increased rapidly starting at around 0.5 for PNG and 0.6 for FNQ, then exceeding 0.9 at age four years in both populations. Genetic gains due to indirect selection increased with age, in which the gains in FNQ were generally larger than those in PNG. Selection efficiency based on gain per year as a ratio of the gains from indirect selection to direct selection may conclude resulted the optimum age for selection at age two years old in both of PNG and FNQ population.

  20. Reduced triacylglycerol mobilization during seed germination and early seedling growth in Arabidopsis containing nutritionally important polyunsaturated fatty acids

    Directory of Open Access Journals (Sweden)

    Pushkar Shrestha

    2016-09-01

    Full Text Available There are now several examples of plant species engineered to synthesise and accumulate nutritionally important polyunsaturated fatty acids in their seed triacylglycerols (TAG. The utilization of such TAG in germinating seeds of such transgenic plants was unknown. In this study, we examined the TAG utilization efficiency during seed germination in transgenic Arabidopsis seeds containing several examples of these fatty acids. Seed TAG species with native fatty acids had higher utilization rate than the TAG species containing transgenically produced polyunsaturated fatty acids. Conversely, quantification of the fatty acid components remaining in the total TAG after early stages of seed germination revealed that the undigested TAGs tended to contain an elevated level of the engineered polyunsaturated fatty acids (PUFA. LC-MS analysis further revealed asymmetrical mobilization rates for the individual TAG species. TAGs which contained multiple PUFA fatty acids were mobilized slower than the species containing single PUFA. The mobilised engineered fatty acids were used in de novo membrane lipid synthesis during seedling development.

  1. Germination success and seedling development of Argania spinosa under different climatic conditions and browsing intensity.

    Science.gov (United States)

    Zunzunegui, María; Jáuregui, Juan; Ain-Lhout, Fatima; Boutaled, Said; Alvarez-Cansino, Leonor; Esquivias, Maripaz

    2013-01-01

    The present study assesses whether the germination and establishment success of Argania spinosa seeds are affected by the environmental conditions under which the mother plant has grown. Seeds from three populations with different climatic conditions and herbivory intensity were collected and sown in the laboratory after different treatments. Our study suggests that the seed germination process and initial stages of seedling growth are adaptive. Seeds from the population of Agadir with the highest herbivory pressure and high air relative humidity in summer (due to the proximity to the sea) were stimulated by acid treatment, and showed a lower root/stem ratio, which allows them to take advantage of the atmospheric water resources. Seeds from the Mountain population, where the most arid environmental conditions were found, produced early-germinating seeds with the highest root/stem ratio that would facilitate seedling establishment when the harshest environmental conditions appear in summer.

  2. MYCORRHIZAL FUNGI INCREASED EARLY GROWTH OF TROPICAL TREE SEEDLINGS IN ADVERSE SOIL

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    Maman Turjaman

    2009-06-01

    Full Text Available The rate of reforestation  has increased throughout the countries in Southeast Asia region during the last 20 years.  At the same time, inconvenient situations such as forest destruction, forest exploitation, illegal logging, clear-cut forest areas, old agricultural lands, post-wildfire areas, conversion  of natural  forests into  plantations, resettlement areas, mine  lands,  and amended adverse soils have also been increasing  significantly. Mycorrhizas, hovewer,  play important role  to increase  plant  growth,  enrich  nutrient content  and enhance  survival rates of forest tree species in temperate  and sub-tropical  regions.  Unfortunately, a little information so far is available  regarding  the effect of mycorrhizas on growth  of tree species growing  in tropical  forests. In relevant,  several experiments  were carried  out to determine whether  ectomycorrhizal (ECM fungi and arbuscular  mycorrhizal (AM fungi can enhance mycorrhizal colonization, nutrient content, and plant growth of some tropical rain forest tree species in Indonesia under nursery  and field conditions.   The families of tropical  tree species used in the experiment were  Thymelaeaceae (Aquilaria crassna, Leguminosae  (Sesbania grandifolia, Guttiferae (Ploiarium alternifolium and Calophyllum hosei, Apocynaceae (Dyera polyphylla and Alstonia scholaris, and Dipterocarpaceae (Shorea belangeran. These families are important as they provide timber  and non-timber  forest products (NTFPs.   This paper discusses the role of mycorrhizal fungi in increasing  early  growth  of tropical  tree seedlings in adverse soil.

  3. Effect of temperature and nutrients on the growth and development of seedlings of an invasive plant.

    Science.gov (United States)

    Skálová, Hana; Moravcová, Lenka; Dixon, Anthony F G; Kindlmann, P; Pyšek, Petr

    2015-04-28

    Plant species distributions are determined by the response of populations to regional climates; however, little is known about how alien plants that arrive in central Europe from climatically warmer regions cope with the temperature conditions at the early stage of population development. Ambrosia artemisiifolia (common ragweed) is an invasive annual plant causing considerable health and economic problems in Europe. Although climate-based models predict that the whole of the Czech Republic is climatically suitable for this species, it is confined to the warmest regions. To determine the factors possibly responsible for its restricted occurrence, we investigated the effects of temperature and nutrient availability on its seedlings. The plants were cultivated at one of seven temperature regimes ranging from 10 to 34 °C, combined with three nutrient levels. The data on the rate of leaf development were used to calculate the lower developmental threshold (LDT, the temperature, in °C, below which development ceases), the sum of effective temperatures (SET, the amount of heat needed to complete a developmental stage measured in degree days above LDT) and width of the thermal window. The rate of development decreased with decrease in temperature and nutrient supply. Besides this, the decrease in the availability of nutrients resulted in decreased LDT, increased SET and wider thermal window. The dependence of LDT and SET on the availability of nutrients contradicts the concept that thermal constants do not vary. Our results highlight temperature as the main determinant of common ragweed's distribution and identify nutrient availability as a factor that results in the realized niche being smaller than the fundamental niche; both of these need to be taken into account when predicting the future spread of A. artemisiifolia.

  4. Establishment and development of Tabebuia rosea (Bignoniaceae) seedlings in a semideciduous tropical forest under management, Pacific coast of Mexico

    OpenAIRE

    Mora Santacruz, Antonio; Valdez Hernández, Juan Ignacio; Ángeles Pérez, Gregorio; Musálem Santiago, Miguel Ángel; Vaquera Huerta, Humberto

    2014-01-01

    We evaluated the effect of soil “scarification” and vegetation clearing treatments on the natural regeneration and initial development of Tabebuia rosea (Bertold) DC. seedlings in a moderate sized semideciduous tropical forest subjected to wood harvesting on the coast of Jalisco, Mexico. The treatments were applied under “seed” trees, and the number of germinated seedlings and their development were evaluated for nine months. Soil “scarification” promoted seed germination and initial seedling...

  5. Development of successive cambia, cambial activity, and their relationship to physiological traits in Ipomoea arborescens (Convolvulaceae) seedlings

    National Research Council Canada - National Science Library

    Teresa Terrazas; Silvia Aguilar-Rodríguez; Clara Tinoco Ojanguren

    2011-01-01

    .... We studied the anatomy of Ipomoea arborescens seedlings to define when cambium is differentiated, to determine how many cambia differentiate in one year of growth, and to relate the development...

  6. [Establishment and development of Tabebuia rosea (Bignoniaceae) seedlings in a semideciduous tropical forest under management, Pacific coast of Mexico].

    Science.gov (United States)

    Santacruz, Antonio Mora; Valdez Herández, Juan Ignacio; Angeles Pérez, Gregorio; Musálem Santiago, Miguel Angel; Vaquera Huerta, Humberto

    2006-12-01

    We evaluated the effect of soil "scarification" and vegetation clearing treatments on the natural regeneration and initial development of Tabebuia rosea (Bertold) DC. seedlings in a moderate sized semideciduous tropical forest subjected to wood harvesting on the coast of Jalisco, Mexico. The treatments were applied under "seed" trees, and the number of germinated seedlings and their development were evaluated for nine months. Soil "scarification" promoted seed germination and initial seedling development, while the control of the competing vegetation increased the seedling growth and reduced their mortality. These results should be taken into account for the natural regeneration of this species, after clearing, to improve wood production, and should be incorporated into the silvicultural techniques currently developed in the region.

  7. Early Adolescent Ego Development.

    Science.gov (United States)

    James, Michael A.

    1980-01-01

    Presented are the theoretical characteristics of social identity in early adolescence (ages 10 to 15). It is suggested that no longer is identity thought to begin with adolescence, but may have its beginnings in the preteen years. The article draws heavily on Eriksonian concepts. (Editor/KC)

  8. Effect of different substrates for organic agriculture in seedling development of traditional species of Solanaceae

    Energy Technology Data Exchange (ETDEWEB)

    Olaria, M.; Nebot, J.F.; Molina, H.; Troncho, P.; Lapeña, P.; Llorens, E.

    2016-11-01

    Sowing of seedlings is one of the most critical processes on the establishment of a crop, since the future development of the plant depends largely on its health when is planted on the field. Moreover, organic agriculture has to deal with the low application of fertilizers and pesticides, which hinder the growth of seedlings. In this work, we studied the big influence of different mixtures of substrates suitable for organic agriculture based on peat, coconut husk and vermicompost in traditional varieties of tomato, pepper and eggplant. Our results indicate that the use of coconut husk based substrates in organic agriculture can reduce the growth of seedlings between 20 and 30% compared with peat-based substrates. Moreover, the plants growth in this substrate showed lower levels of chlorophyll and lower weight, but the results are strongly dependent on the species tested. Comparison between traditional plants demonstrates that traditional varieties are strongly influenced by the substrate, whereas the growth of a commercial variety of tomato barely differs when different substrates are used. The election of the substrate in organic agriculture is critical to the correct development of the plant, especially when traditional plant varieties are used. (Author)

  9. Effect of phosphate solubilizing bacteria on the development of coffee seedlings.

    Directory of Open Access Journals (Sweden)

    Carlos Adolfo Cisneros-Rojas

    2016-12-01

    Full Text Available The aim of this study was to evaluate the effect of solubilizing phosphate bacterias (BSF, Kocuria sp. and Bacillus subtilis, on the development of coffee seedlings Castillo variety. The experiment was conducted in a greenhouse condition, in Palmira, Colombia during 2013-2014 years. The experimental design was completely random, with nine treatments and ten repetitions. The treatments were established under three types of substrates for the seedlings: natural soil (Typic Melanudand + decomposed coffee pulp (1:1 lacking or presenting BSF (treatments 1-4, natural soil + decomposed coffee pulp (1:1 + phosphate rock (RF with or without microorganisms (treatments 5-8, and natural soil without BSF subjected to fertilization with diammonium phosphate (DAP (treatment 9. The application of decomposed coffee pulp with and without RF and BSF favored the availability of phosphorus that helped to the development of coffee seedlings, the above was re ected in the chemical analysis of the substrate and the response of variables, root and total dry aerial weight. Length and volume root, foliar P and recovery phosphorus ef ciency (ERF, did not present signi cant differences.

  10. The availability of bone powder as inorganic element source on growth and development in wheat seedlings.

    Science.gov (United States)

    Genisel, Mucip; Erdal, Serkan; Turk, Hulya; Dumlupinar, Rahmi

    2012-06-01

    Bone powder (BP), a by-product of cattle slaughtering plants, consists of fat, protein, amino acids, inorganic elements and vitamins. It is used as bone meal in biomedical and feed industry because of its rich content. In addition, bone contains a large amount of inorganic elements especially calcium (Ca) and phosphorus (P), which the plants need to maintain their physiological and biochemical processes. BP has been used as Ca and P source in agriculture for many years; however, its effects on plant growth and development have not yet been studied in detail. The present study aimed to determine the effects of BP on dry weight and contents of total chlorophyll, soluble protein and sugar as indicators of physiological response in the leaves. For this purpose, bone powder solutions (BPS) were prepared at different concentrations (0.5%, 1%, 1.5% and 2%) and applied to growing media of the 10-day wheat seedlings. Afterward, the 14-day seedlings were harvested, and the effects of BPS on plant response were determined. The results showed that BPS treatments significantly stimulated dry weight and contents of total chlorophyll, protein and sugar compared to control seedlings. The best stimulatory effect of BPS was determined at 1% concentration. According to these results, it is possible to say that BP may be used to meet the inorganic element requirements of plants in poor soils and hydroponic systems.

  11. Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains.

    Science.gov (United States)

    de Melo, Risolandia Bezerra; Franco, Augusto César; Silva, Clovis Oliveira; Piedade, Maria Teresa Fernandez; Ferreira, Cristiane Silva

    2015-04-28

    Successful germination and seedling establishment are crucial steps for maintenance and expansion of plant populations and recovery from perturbations. Every year the Amazon River and its tributaries overflow and flood the adjacent forest, exerting a strong selective pressure on traits related to seedling recruitment. We examined seed characteristics, stored reserves, germination, seedling development and survival under water of eight representative tree species from the lower portions of the flood-level gradient to identify adaptive strategies that contribute to their regeneration in this extreme ecosystem. Submerged seedlings were assessed for longevity and survival until they showed symptoms of injury. At this point, the remaining healthy seedlings were planted in unsaturated soil to monitor recovery after re-exposure to air over 30 days. All small (seed mass ≤0.17 g) seeds had epigeal phanerocotylar-type germination, a trait that would allow plants to acquire light and CO2 in the shortest time. Cell wall storage polysaccharide was a major component of all seeds, suggesting plant investment in structural reserves. Seven of the eight species germinated and formed healthy seedlings under water that endured submersion without any apparent injury for periods of 20-115 days, depending on the species. Seedlings of some species changed the direction of root growth and grew towards the surface of the water, which might have increased the uptake of oxygen to the tissues. Only one of the seven species did not survive re-exposure to air. Species able to germinate and produce seedlings under submersion, which subsequently are able to establish in aerated soils, would have more time available for terrestrial growth. This is critical for colonization of lower portions of the flood-level gradient where establishment is constrained by the short terrestrial phase that precedes the next flood.

  12. Gibberellic acid (GA3) enhance seed water uptake, germination and early seedling growth in sugar beet under salt stress.

    Science.gov (United States)

    Jamil, Muhammad; Rha, Eui Shik

    2007-02-15

    The study was carried out to assess whether water uptake could be improved in sugar beet seeds and salt tolerance at the germination and early seedling stage by soaking the seeds for 10 h in distilled water (control), 100, 150 and 200 mg L(-1) GA3. Electrical Conductivity (EC) values of the NaCl solution were 0.0 (control), 4.7, 9.4 and 14.1 dS n(-1) NaCl. Priming increased the final germination percentage and the germination rate (1/t 50, where t 50 is the time to 50% of germination) under saline condition. Water uptake of primed seeds also increased significantly with increasing concentration of GA3 as compared to control. Priming also alleviated the adverse effect of salt stress on sugar beet in terms of roots and shoots lengths and fresh weights of plants, roots and shoots.

  13. Arabidopsis NITRILASE 1 Contributes to the Regulation of Root Growth and Development through Modulation of Auxin Biosynthesis in Seedlings.

    Science.gov (United States)

    Lehmann, Thomas; Janowitz, Tim; Sánchez-Parra, Beatriz; Alonso, Marta-Marina Pérez; Trompetter, Inga; Piotrowski, Markus; Pollmann, Stephan

    2017-01-01

    Nitrilases consist of a group of enzymes that catalyze the hydrolysis of organic cyanides. They are found ubiquitously distributed in the plant kingdom. Plant nitrilases are mainly involved in the detoxification of ß-cyanoalanine, a side-product of ethylene biosynthesis. In the model plant Arabidopsis thaliana a second group of Brassicaceae-specific nitrilases (NIT1-3) has been found. This so-called NIT1-subfamily has been associated with the conversion of indole-3-acetonitrile (IAN) into the major plant growth hormone, indole-3-acetic acid (IAA). However, apart of reported functions in defense responses to pathogens and in responses to sulfur depletion, conclusive insight into the general physiological function of the NIT-subfamily nitrilases remains elusive. In this report, we test both the contribution of the indole-3-acetaldoxime (IAOx) pathway to general auxin biosynthesis and the influence of altered nitrilase expression on plant development. Apart of a comprehensive transcriptomics approach to explore the role of the IAOx route in auxin formation, we took a genetic approach to disclose the function of NITRILASE 1 (NIT1) of A. thaliana. We show that NIT1 over-expression (NIT1ox) results in seedlings with shorter primary roots, and an increased number of lateral roots. In addition, NIT1ox plants exhibit drastic changes of both free IAA and IAN levels, which are suggested to be the reason for the observed phenotype. On the other hand, NIT2RNAi knockdown lines, capable of suppressing the expression of all members of the NIT1-subfamily, were generated and characterized to substantiate the above-mentioned findings. Our results demonstrate for the first time that Arabidopsis NIT1 has profound effects on root morphogenesis in early seedling development.

  14. Auxin efflux facilitator and auxin dynamism responsible for the gravity-regulated development of peg in cucumber seedlings

    Science.gov (United States)

    Takahashi, Hideyuki; Watanabe, Chiaki; Fujii, Nobuharu; Miyazawa, Yutaka

    Cucumber seedlings develop a protuberance, peg, by which seed coats are pulled out just af-ter germination. The peg is usually formed on the lower side of the transition zone between hypocotyl and root of the seedlings grown in a horizontal position. Our previous spaceflight experiment showed that unilateral positioning of a peg in cucumber seedlings occurred due to its suppression on the upper side of the transition zone because seedlings grown in microgravity developed a peg on each side of the transition zone. We also showed that auxin was a major factor responsible for peg development. There was a redistribution of auxin in the gravistimu-lated transition zone, decreasing IAA level on the upper side, and IAA application induced a peg on both lower and upper sides of the transition zone. In addition, peg was released from its suppression in the seedlings treated with inhibitors of auxin efflux. Namely, two pegs devel-oped in the TIBA-treated seedlings even when they were grown in a horizontal position. These results imply that a reduction of auxin level due to its efflux is required for the suppression of peg development on the upper side of the transition zone in a horizontal position. To under-stand molecular mechanism underlying the negative control of morphogenesis by graviresponse in cucumber seedlings, we isolated cDNAs of auxin efflux facilitators, CsPINs, from cucumber and examined the expressions of their proteins, in relation to the redistribution of endogenous auxin and peg development. We isolated six cDNAs of PIN homologues CsPIN1 to CsPIN6 from cucumber. By immunohistochemical study using some of their anti-bodies, we revealed that CsPIN1 was localized in endodermis, vascular tissue and pith around the transition zone of cucumber seedlings. In cucumber seedlings grown in a vertical position with radicles pointing down, CsPIN1 in endodermal cells was mainly localized on the plasma membrane neighboring vascular bundle but not on the plasma membrane

  15. Rhododendron javanicum (Blume Benn. AND Rhododendron sessilifolium J.J. Sm. GERMINATION AND SEEDLINGS DEVELOPMENT ON DIFFERENT GROWING MEDIA AND FERTILIZERS APPLICATION

    Directory of Open Access Journals (Sweden)

    Wiguna Rahman

    2013-07-01

    Full Text Available Growing medium is one of the most important factor for ex situ conservation of Rhododendron. Study on different growing media available locally were conducted for germinating and developing the seedlings of Rhododendron javanicum and R. sessilifolium. Tree fern roots medium was suitable for germination and developing Rhododendron javanicum and R. sessilifolium seedlings. Growing medium for bigger seedlings using "Cibodas compost" was better than "Cibodas compost and rice husk" for the development of Rhododendron seedlings. Fertilizer application did not showed significant effect on R. sessilifolium seedlings. However, low concentration of fertilizer was recommended rather than high concentration of fertilizer. Some fertilizers at different applications were tested on the development of R. sessilifolium seedlings.

  16. Asymbiotic seed germination and in vitro seedling development of Paphiopedilum spicerianum: An orchid with an extremely small population in China

    Directory of Open Access Journals (Sweden)

    Ying Chen

    2015-01-01

    Full Text Available Paphiopedilum spicerianum  is listed as one of the country’s Wild Plants with Extremely Small Populations (PSESP. Procedures were developed for asymbiotic seed germination and seedling development aimed at producing seedlings for reintroduction. The highest germination was achieved in RECW with a 24 h dark cycle after pretreatment with 1% NaOCl for 40 min after 30 days from germination. However, these protocorms remained white and did not develop further. Although germination was lower under the same conditions in MSCW, it resulted in healthier and greener protocorms. Of four suitable media tested to promote seedling formation, Hyponex No 1 medium with 1.0mgl−1α-naphthalene acetic acid, 0.5gl−1 activated charcoal and 10% banana homogenate was the most effective. Advanced seedling development was seen in all six tested media during a 4 month growing period, with the highest leaf growth rate seen in the same media used for seedling formation, supplemented with 1.0mgl−16-benzyladenine added to promote leaf growth. Fluorescein diacetate (FDA tests on seeds showed that higher salt concentrations in the medium and longer duration of exposure to NaOCl reduce germination because of damaging effects on the testa and the embryo cells.

  17. Development of successive cambia, cambial activity, and their relationship to physiological traits in Ipomoea arborescens (Convolvulaceae) seedlings.

    Science.gov (United States)

    Terrazas, Teresa; Aguilar-Rodríguez, Silvia; Ojanguren, Clara Tinoco

    2011-05-01

    The seedling stage is one of the most critical phases in the life history of plants; during this stage, plants must develop efficient conductive and storage systems before the end of the favorable season. Little is known about the origin of successive cambia in seedlings of tree species of Ipomoea or about how many cambia are produced in one growth season. We studied the anatomy of Ipomoea arborescens seedlings to defi ne when cambium is differentiated, to determine how many cambia differentiate in one year of growth, and to relate the development of successive cambia to physiological aspects of growth. Seedlings from 5 to 425 d of age were harvested, and their morphology as well as CO(2) and water exchange, were evaluated at 5 and 60 d after germination. Six stages of development were established to study origin of cambia. Cambium was differentiated 5 d after germination, at a time when seedlings had photosynthetic cotyledons with high specific area, assimilation rate, and stomatal conductance. Differentiation of the fi rst successive cambium occurred inparenchyma cells below the endodermis or starch sheath. Development of reverse cambium and intraxylary phloem cambiumdemonstrated that ontogenetic shifts may occur in different stem regions. In the 10-mo-old plants, all cambia reactivated, and earlywood wide vessels were differentiated. The origin of successive cambia, the occurrence of more than one type of cambium, and parenchyma proliferation are features shared by I. arborescens with its climbing ancestors as a strategy for survival in the harsh environment of tropical deciduous forests.

  18. Pre-sowing Seed Treatments in Direct-seeded Early Rice: Consequences for Emergence, Seedling Growth and Associated Metabolic Events under Chilling Stress.

    Science.gov (United States)

    Wang, Weiqin; Chen, Qian; Hussain, Saddam; Mei, Junhao; Dong, Huanglin; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

    2016-01-19

    Double direct-seeding for double rice cropping is a simplified, labor saving, and efficient cropping system to improve multiple-crop index and total rice production in central China. However, poor crop establishment of direct-seeded early rice due to chilling stress is the main obstacle to wide spread of this system. A series of experiments were conducted to unravel the effects of pre-sowing seed treatments on emergence, seedling growth and associated metabolic events of direct-seeded early rice under chilling stress. Two seed priming treatments and two seed coating treatments were used in all the experiments. A non-treated control treatment was also maintained for comparison. In both the field and growth chamber studies, seed priming with selenium or salicylic acid significantly enhanced the emergence and seedling growth of rice compared with non-treated control. Nevertheless, such positive effects were not apparent for seed coating treatments. Better emergence and vigorous seedling growth of rice after seed priming was associated with enhanced α-amylase activity, higher soluble sugars contents, and greater respiration rate in primed rice seedlings under chilling stress. Taking together, these findings may provide new avenues for understanding and advancing priming-induced chilling tolerance in direct-seeded early rice in double rice cropping system.

  19. Proteome analysis of early-stage soybean seedlings under flooding stress.

    Science.gov (United States)

    Hashiguchi, Akiko; Sakata, Katsumi; Komatsu, Setsuko

    2009-04-01

    Proteomic analyses of soybean seedlings responding to flooding were conducted to identify proteins involved in such response. Soybean was germinated for 48 h and then subjected to flooding stress for 6-48 h. Proteomic analysis of hypocotyl and root was used in a time-dependent manner, and altered proteins were identified using soybean protein data file constructed for this research. Under flooding stress, 35 proteins were up-regulated, whereas 16 proteins were down-regulated at a 24-h time point. Changes in energy generation was recognized because several glycolytic enzymes were up-regulated. General stress response was also shown to occur as various reactive oxygen species scavengers were up-regulated. Other identified proteins with diverse functional categories suggest that flooding stress includes not only hypoxic stress, but also other stresses such as weak light, disease, and water stresses. In addition, proteins with unknown functions were shown to be positioned as hubs which activate other proteins in system response networks by protein-protein interaction analysis, suggesting that this type of interaction analysis is useful for screening of important factors in plant response to environmental stresses.

  20. Evolutionary and ecological correlates of early seedling morphology in East African trees and shrubs.

    Science.gov (United States)

    Zanne, Amy E; Chapman, Colin A; Kitajima, Kaoru

    2005-06-01

    Seed size and cotyledon morphology are two key juvenile traits that have evolved in response to changes in plant species life-history strategies and habitat associations. Correlations of these traits with each other and with other juvenile traits were examined for 70 species of trees and shrubs in Kibale National Park, Uganda. Although species with photosynthetic cotyledons were more abundant than in other tropical floras, both univariate and multivariate analyses supported trait associations expected from the literature. Trait values varied continuously across species, yet mean trait values differed significantly among habitat association types. Species with large seeds, large seedlings, thick storage cotyledons, slow germination, large-stature adults, and dispersal by large animals were common in forest and gap habitats. An opposite suite of traits was common in open habitats (grassland and edge). Analyses incorporating phylogeny (independent contrasts and omnibus tests) confirmed that these suites of traits showed correlated evolution. Cotyledon functional morphology yielded a strong phylogenetic signal, while seed mass was labile. Nevertheless, contingent change tests found that evolutionary change from photosynthetic to reserve cotyledons was more likely when disperser and perhaps seed size of ancestral species were already large, suggesting a strong interdependency among these traits.

  1. Development and properties of a wax ester hydrolase in the cotyledons of jojoba seedlings.

    Science.gov (United States)

    Huang, A H; Moreau, R A; Liu, K D

    1978-03-01

    The activity of a wax ester hydrolase in the cotyledons of jojoba (Simmondsia chinensis) seedlings increased drastically during germination, parallel to the development of the gluconeogenic process. The enzyme at its peak of development was obtained in association with the wax body membrane, and its properties were studied. It had an optimal activity at alkaline pH (8.5-9). The apparent K(m) value for N-methylindoxylmyristate was 93 muM. It was stable at 40 C for 30 min but was inactivated at higher temperature. Various divalent cations and ethylenediaminetetraacetate had little effect on the activity. p-Chloromercuribenzoate was a strong inhibitor of the enzyme activity, and its effect was reversed by subsequent addition of dithiothreitol. It had a broad substrate specificity with highest activities on monoglycerides, wax esters, and the native substrate (jojoba wax).

  2. In-ovulo embryo culture and seedling development of cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Stewart, J M; Hsu, C L

    1977-01-01

    A convenient and reliable method for culturing cotton embryos is needed to obtain interspecific hybrids of this genus. C.A. Beasley and I.P. Ting (Amer. J. Bot. 60, 130, 1973) developed a phytohormone-supplemented medium (BTP) upon which the growth of ovules was similar that of in situ ovules. This medium was examined for in-ovulo embryo culture. Although good ovule growth occurred on BTP no embryos developed to maturity. However, when the medium was supplemented with NH 4 (+) , more than 50% of the ovules produced mature embryos, and many of these germinated precociously after 8-10 weeks of culture. After germination seedlings were established on a separate medium designed to give balanced root and shoot growth. Subsequently young plants could be transferred to pots for greenhouse culture.

  3. Disruption of germination and seedling development in Brassica napus by mutations causing severe seed hormonal imbalance

    Directory of Open Access Journals (Sweden)

    Tung eNguyen

    2016-03-01

    Full Text Available The Brassica napus (oilseed rape accession 1012-98 shows a disturbed germination phenotype that was thought to be associated with its lack of testa pigmentation and thin seed coat. Here we demonstrate that the disturbed germination and seedling development are actually due to independent mutations that disrupt the balance of hormone metabolites and their regulators in the seeds. High-throughput UPLC-MS/MS hormone profiling of seeds and seedlings before and after germination revealed that 1012-98 has a severely disturbed hormone balance with extremely atypical, excessive quantities of auxin and ABA metabolites. The resulting hypersensitivity to abscisic acid (ABA and a corresponding increase in dormancy often results in death of the embryo after imbibition or high frequencies of disturbed, often lethal developmental phenotypes, resembling Arabidopsis mutants for the auxin regulatory factor gene ARF10 or the auxin-overproducing transgenic line iaaM-OX. Molecular cloning of Brassica ARF10 orthologues revealed four loci in normal B. napus, two derived from the Brassica A genome and two from the C genome. On the other hand, the phenotypic mutant 1012-98 exhibited amplification of C-genome BnaC.ARF10 copy number along with a chimeric allele originating from recombination between homoeologous A and C genome loci which lead to minor increase of Bna.ARF10 transcription on the critical timepoint for seed germination, the indirect regulator of ABI3, the germinative inhibitor. Bna.GH3.5 expression was upregulated to conjugate free auxin to IAA-asp between 2-6 DAS. Functional amino acid changes were also found in important DNA binding domains of one BnaC.ARF10 locus, suggesting that regulatory changes in Bna.ARF10 are collectively responsible for the observed phenotpyes in 1012-98. To our knowledge, this study is the first to report disruption of germination and seedling development in Brassica napus caused by the crosstalk of auxin-ABA and the

  4. Gravity-regulated formation of the peg in developing cucumber seedlings

    Science.gov (United States)

    Takahashi, H.; Scott, T. K.

    1994-01-01

    It has been proposed that peg formation in the vascular transition region (TR zone) between the hypocotyl and the root in Cucurbitaceae seedlings is a gravimorphogenetic phenomenon. Initiation of the peg became visible 36 h after imbibition when cucumber (Cucumis sativus L. cv. Burpee Hybrid II) seeds were germinated in a horizontal position at 24 degrees C in the dark. Simultaneously, sedimented amyloplasts (putative statoliths) were apparent in the sheath cells surrounding the vascular strands, and in the cortical cells immediately adjacent to them, in the TR zone. In contrast, the other cortical cells, some of which were destined to develop into the peg, contained amyloplasts which were not sedimented. These results suggest that the graviperception mechanism for peg formation may be like that of statoliths in shoot gravitropism. By 48 h following imbibition, the cells of the TR zone still had sedimented amyloplasts but had lost their sensitivity to gravity, possibly because of their maturation.

  5. THE EFFECT OF INDUSTRIAL WATER ON THE GERMINATION OF SEEDS AND THE DEVELOPMENT OF SEEDLINGS OF PISUM SATIVUM L.

    Directory of Open Access Journals (Sweden)

    Liliana Cristina SOARE

    2011-01-01

    Full Text Available The aim of the research was to highlight the influence of industrial water on the germination of seeds and the development of seedlings of Pisum sativum L., so that the impact of these water on the plants may be assessed, in case of accidental spills. The analysis of polluted industrial water indicates the presence of Cr, Fe, Ni, Pb, Cd, Cu, and Zn concentrations higher than CMA, except Cd, which was below the detection limit, and Cu. On leaving the neutralization station, metal concentration was below the CMA, except Pb. The early ontogenetic stages of root development were much more sensitive to water pollution. For the experimental variants where the seeds were immersed in water treated and discharged from the neutralization station, there were no significant differences between the experimental variants, which also confirms the results of the chemical analysis. The metals absorbed by the roots were translocated into the stem, which affected its growth processes. Along with the increased dilution in the polluted water, the average stem length also increased, which was also true of the root growth. Root and stem growth can represent biomarkers of environmental pollution by metals.

  6. Development and plasticity of endangered shrub Lindera melissifolia (Lauraceae) seedlings under contrasting light regimes

    Science.gov (United States)

    Brian R Lockhart; Emile S Gardiner; Theran Stautz; Theodor D. Leininger

    2012-01-01

    Lindera melissifolia (Walt.) Blume seedlings were raised in a growth chamber to determine the effects of light availability on shoot growth pattern, and basic leaf and stem growth. Lindera melissifolia seedlings exhibited a sympodial shoot growth pattern for 3 months following emergence from the soil medium, but this pattern was characterized by a reduction in leaf...

  7. Improved recruitment and early growth of Scots pine (Pinus sylvestris L.) seedlings after fire and soil scarification.

    NARCIS (Netherlands)

    Hille, M.G.; Ouden, den J.

    2004-01-01

    The success of seedling recruitment of Scots pine (Pinus sylvestris L.) is strongly dependent on soil surface properties, such as humus depth and moisture content. In an undisturbed forest floor, seedlings are seldom able to become established due to the high incidence of desiccation in the organic

  8. Emergence and early development of cupuassu seedlings grown on different substrates and under different conditions of shade =Emergência e desenvolvimento inicial de plântulas de cupuaçu cultivadas sob diferentes substratos e condições de sombreamento

    Directory of Open Access Journals (Sweden)

    Elias Ariel Moura

    2016-02-01

    Full Text Available O The cupuassu can be propagated either sexually or asexually, with seeds being the process most widely employed. Suitable environments for the production of seedlings can therefore provide better conditions for initial growth in the field, and contribute to an increase in the homogeneity and health, and to a reduction in the mortality of plants when planting, with factors such as light and type of substrate being important for germination and initial emergence. To this effect, the aim of the present study was to evaluate the effect of different substrates, and the influence of shading on emergence and initial growth in cupuassu seedlings. The experiment was carried out at Embrapa Roraima, using a completely randomised design in a 3 x 7 factorial scheme, comprising different environments (a plot with no covering, a plot with sombrite covering, giving 50% shade, and a plot with a clear-plastic, 100-micron covering combined with different substrates (sand, soil, vivatto®, sawdust, sand+soil, sand+soil+vivatto® and sand+soil+sawdust. Percentage emergence and emergence speed index (ESI were evaluated at five days after seeding, and shoot length, number of leaves, leaf area, root-system length, stem diameter, and shoot and root-system dry weight were evaluated at 50 days. It was found that the best values for percentage emergence, ESI and initial development of the cupuassu seedlings were obtained when using a substrate consisting of sand+soil+sawdust. The environment with 50% shade affords greater percentage emergence, ESI, stem diameter and root dry mass. = O cupuaçu pode ser propagado por via sexuada ou assexuada, sendo a via seminífera o processo mais utilizado. Dessa forma, ambientes apropriados para a produção de mudas propiciam melhores condições para o crescimento inicial em campo, colaborando para o aumento da homogeneidade, sanidade e redução da mortalidade de plantas no momento do plantio. Assim, fatores como luz e tipo de

  9. Early growth of Quercus castaneifolia (C.A. Meyer) seedlings as affected by weeding, shading and irrigation.

    Science.gov (United States)

    Mirzaei, Javad; Tabari, Masoud; Daroodi, Hadi

    2007-08-01

    The influence of shading, irrigation and weeding on survival, growth and morphology of 1-year Quercus castaneifolia seedlings was studied in north of Iran. The seedlings were grown under eight treatments including full-light versus artificial shading, irrigation versus non-irrigation and weed presence versus weed removing at three replicates. At the end of the first growing season seedling survival in all treatments was 100%. Weed removing had positive effect on height, diameter growth, slenderness coefficient and leaf area of Q. castaneifolia. Irrigation enhanced diameter growth and leaf area and shading increased leaf area. Irrigation had no significant effect on plant growth where the weed was removed. In weed plots seedlings growth and leaf area were greater in shading than in full-light. The results indicated that for 1 year Q. castaneifolia seedlings, weeding, in contrast to irrigation, is an essential factor. Where the weed competition is a difficulty, plantation with higher stem length should be applied.

  10. Choreography of early thalamocortical development.

    Science.gov (United States)

    Molnár, Zoltán; Higashi, Shuji; López-Bendito, Guillermina

    2003-06-01

    Thalamic axons, which carry most of the information from the sensory environment, are amongst the first projections to reach the cerebral cortex during embryonic development. It has been proposed that the scaffold of early generated cells in the ventral thalamus, internal capsule and preplate play a pivotal role in their deployment through sharp gene expression boundaries. These ideas were recently evaluated in various strains of mutant mice. In Tbr1, Gbx2, Pax6 KO both thalamic and corticofugal projections fail to traverse the striatocortical junction. In both Emx2 and Pax6 KO brains, the misrouted thalamic afferents are accompanied by displacements of the pioneering projections from the internal capsule. Regardless of their altered route, thalamic afferents in the reeler and L1 KO mice seem to be able to redistribute themselves on the cortical sheet and establish normal periphery-related representation in the somatosensory cortex. Early neural activity delivered through the thalamic projections is thought to be involved in the realignment process of thalamic axons at the time of their accumulation in the subplate layer. However, axonal growth and the early topographic arrangement of thalamocortical fiber pathways appear normal in the Snap25 KO, where action potential mediated synaptic vesicle release is disrupted. We therefore suggest that intercellular communication mediated by constitutive secretion of transmitters or growth factors might play a dominant role during early thalamocortical development.

  11. Cucumber seedling dependence on cotyledonary leaves for early growth Dependência das folhas cotiledonares para o crescimento inicial de pepino

    Directory of Open Access Journals (Sweden)

    Dilson Antônio Bisognin

    2005-06-01

    Full Text Available The objective of this work was to evaluate the dependence of cucumber (Cucumis sativus L. seedlings on cotyledonary leaves for early growth and establishment. Sets of two uniform emerging seedlings were used to quantify the initial growth and dry matter accumulation, as well as the intensity and stage of cotyledon damage in seedling establishment and to determine cotyledon protein, amino acid and carbohydrate contributions to the growing seedling. Cucumber seedling establishment was found to be highly dependent on cotyledonary leaves. Root system establishment was highly dependent on the health of the aerial part. One cotyledon was enough to maintain aerial growth of seedlings after unfolding the first true leaf. Cucumber seedlings depended on both cotyledons to keep root system growth at least until leaf area was equivalent to cotyledon area. Covering one or both cotyledons of seedlings with one unfolded leaf increased carbohydrate content of uncovered cotyledon and leaves compared with control seedlings. Cucumber seedlings are highly dependent on cotyledonary leaves and aerial parts are less dependent than root system. Cotyledon damage at early stages of plant establishment would adversely impact crop yield by reducing plant density, an important yield component, or slowing down seedling growth and establishment.O objetivo deste trabalho foi estudar o desempenho das folhas cotiledonares no crescimento inicial e estabelecimento de plântulas de pepino (Cucumis sativus L.. Grupos de duas plântulas uniformemente emergidas foram utilizados para quantificar o crescimento inicial e acúmulo de matéria seca, o efeito da intensidade e época de remoção dos cotilédones sobre o estabelecimento da plântula, e a contribuição de proteínas, aminoácidos e carboidratos dos cotilédones para o crescimento inicial. O estabelecimento das plântulas de pepino foi altamente dependente das folhas cotiledonares. As folhas cotiledonares foram fundamentais

  12. Seed reserve composition and mobilization during germination and early seedling establishment of Cereus jamacaru D.C. ssp. jamacaru (Cactaceae).

    Science.gov (United States)

    Alencar, Nara L M; Innecco, Renato; Gomes-Filho, Enéas; Gallão, Maria Izabel; Alvarez-Pizarro, Juan C; Prisco, José T; Oliveira, Alexandre B De

    2012-09-01

    Cereus jamacaru, a Cactaceae found throughout northeast Brazil, is widely used as cattle food and as an ornamental and medicinal plant. However, there has been little information about the physiological and biochemical aspects involved in its germination. The aim of this study was to investigate its reserve mobilization during germination and early seedling growth. For this, C. jamacaru seeds were germinated in a growth chamber and collected at 0, 2, 4, 5, 6, 8 and 12 days after imbibition for morphological and biochemical analyses. Dry seeds had wrinkled seed coats and large, curved embryos. Lipids were the most abundant reserve, comprising approximately 55% and 65% of the dry mass for cotyledons and the hypocotylradicle axis, respectively. Soluble sugars and starch were the minor reserves, corresponding to approximately 2.2% of the cotyledons' dry mass, although their levels showed significant changes during germination. Soluble proteins corresponded to 40% of the cotyledons' dry mass, which was reduced by 81% at the final period of germination compared to dry seeds. C. jamacaru seed can be classified as an oil seed due to its high lipid content. Moreover, lipids were the main reserve mobilized during germination because their levels were strongly reduced after seed germination, while proteins were the second most utilized reserve in this process.

  13. The Effect of Cd, Zn and Fe on Seed Germination and Early Seedling Growth of Wheat and Bean

    Directory of Open Access Journals (Sweden)

    El Rasafi Taoufik

    2016-09-01

    Full Text Available This study was conducted to evaluate the effect of metals on wheat and bean species. The method uses seed germination and early seedling growth of these plants in the presence of various levels (10, 50, 100, 250, 500, 750 and 1000 mg/L of Cadmium (Cd, Iron (Fe and Zinc (Zn. The inhibition caused by these metals was depending on the concentration used, the metal itself and the plant species. The species had reduced seed germination, root and shoot lengths, tolerance index and percentphyto-toxicity with increasing concentrations of metals. Cadmium was determined to be the most inhibitory metal on these parameters. This metal affected significantly the germination, root and shoot length of the species tested, as well as the tolerance index and percentphytotoxicity starting from 50 mg Cd/l. Under the Iron stress, in general, the inhibition of germination and root length of wheat was reduced from 500 mg Fe/l. The results showed also that the inhibitory effect of increase of Zn levels was seen in root, shoot and tolerance indices. The findings also revealed that the metal toxicity was as follow: Cd > Fe > Zn. Regarding species, the results showed that bean seemed to be more tolerant to the increase of the three metals than wheat.

  14. Effect of acorn mass and size, and early shoot growth on one-year old container-grown RPM™ oak seedlings

    Science.gov (United States)

    Benjamin C. Grossman; Michael A. Gold; Daniel C. Dey

    2003-01-01

    The purpose of this study was to evaluate the influence of seed source, acorn mass and size, and early shoot growth on morphological traits of 1-year-old oak seedlings. Forested bottomlands in the Midwest have been greatly reduced in the past 150 years as a result of conversion to agriculture and recent catastrophic floods. Due to a lack of available hard mast, intense...

  15. Germination and early plant development of ten plant species exposed to titanium dioxide and cerium oxide nanoparticles

    Science.gov (United States)

    Ten agronomic plant species were exposed to different concentrations of nano titanium dioxide (nTiO2) or nano cerium oxide (nCeO2) (0, 250, 500 and 1000 mg/L) to examine potential effects on germination and early seedling development. We modified a standard test protocol develop...

  16. Early prosocial development across cultures.

    Science.gov (United States)

    Callaghan, Tara; Corbit, John

    2017-08-17

    Human prosociality is ubiquitous, even though it may be manifested differently across cultures. Low cost helping and sharing emerge early in development, and at similar levels, across cultures having vastly different sociocultural niches. Developmental trajectories for costly sharing diverge across cultures around middle childhood, in line with differences in the sociocultural niches that children experience. Cultural developmental research has focussed primarily on the emergence and development of prosocial behaviour, and would benefit from an examination of the interplay between psychological (cognitive, motivational) and sociocultural (norms, developmental niche) foundations over ontogeny. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. A high-throughput phenotyping procedure for evaluation of antixenosis against common cutworm at early seedling stage in soybean.

    Science.gov (United States)

    Xing, Guangnan; Liu, Kai; Gai, Junyi

    2017-01-01

    Common cutworm (CCW; Spodoptera litura Fabricius) is a major leaf-feeding pest of soybean in Asia. The previous methods of measuring antixenosis against CCW using adult plant under field or net-room conditions were time-consuming, labor-intensive and precision-inferior. To solve the problems, this study aimed at (i) establishing a high-throughput phenotyping method for evaluating antixenosis against CCW at early seedling stage, (ii) using the procedure to evaluate the antixenosis of an insect-resistant versus -susceptible germplasm population (IRSGP), (iii) validating the proposed method through comparing the results with the historical phenotypic data and phenotyping-genotyping consistency data using PAV (presence/absence variation) markers linked with the identified loci CCW-1 and CCW-2, (iv) and evaluating the efficiency of the novel method through comparisons to the previous methods. A dynamic and efficient evaluation procedure characterized with using V1 stage soybean seedlings infested with third-instar larvae in a micro-net-room in greenhouse with damaged leaf percentage (DLP) as indicator was established and designated V1TMD method. The middle term testing stage is the best dates for identifying resistant and susceptible accessions. The results from the V1TMD method were relatively stable, precise and accurate in comparison with the previous method with the detected most resistant and susceptible accessions consistent to the previous results. The DLP values differentiated obviously to coincide with the resistant and susceptible alleles of the PAV markers Gm07PAV0595 and Gm07PAV0389 tightly linked to the two resistance-related loci, CCW-1 and CCW-2, respectively, in IRSGP. Thus V1TMD is a high-throughput phenotyping method with its estimated efficiency 12 times and period shortening 4 times of those of the previous method. A dynamic and efficient V1TMD method for testing antixenosis against CCW was established, with highly resistant and highly susceptible

  18. Growth of transplanted timber species seedlings in the south of the Colombian Amazon: A preliminary study

    NARCIS (Netherlands)

    Gruezmacher, M.; Duivenvoorden, J.F.

    2008-01-01

    Two commonly used timber species in the area of Amacayacu National Park (Quararibea sp. and Minquartia guianensis) were selected to develop an experiment that compared the early performance of seedlings in mature and old secondary forest. We transplanted seedlings of these species into mature and

  19. CPK3-phosphorylated RhoGDI1 is essential in the development of Arabidopsis seedlings and leaf epidermal cells

    Science.gov (United States)

    Wu, Yan

    2013-01-01

    The regulation of Rho of plants (ROP) in morphogenesis of leaf epidermal cells has been well studied, but the roles concerning regulators of ROPs such as RhoGDIs are poorly understood. This study reports that AtRhoGDI1 (GDI1) acts as a versatile regulator to modulate development of seedlings and leaf pavement cells. In mutant gdi1, leaf pavement cells showed shorter lobes in comparison with those in wild type. In GDI1-14 seedlings (GDI1-overexpression line) the growth of lobes in pavement cells was severely suppressed and the development of seedlings was altered. These results indicate that GDI1 plays an essential role in morphogenesis of epidermal pavement cells through modulating the ROP signalling pathways. The interaction between GDI1 and ROP2 or ROP6 was detected in the leaf pavement cells using FRET analysis. Dominant negative, not constitutively active, DN-rop6 could weaken the effect caused by overexpression of GDI1; because the pleiotropic phenotype of GDI1-14 plants was eliminated in the hybrid line GDI1-14 DN-rop6. GDI1 could be phosphorylated by CPK3. Three conserved Ser/Thr residues in GDI1 were determined as targeted amino acids for CPK3. Overexpression of GDI1(3D), not GDI1(3A), could rescue the abnormal growth phenotypes of gdi1-1 seedlings, demonstrating the impact of GDI1 phosphorylation in the development of Arabidopsis. In summary, these results suggest that GDI1 regulation in morphogenesis of seedlings and leaf pavement cells could be undergone through modulating the ROP signalling pathways and the phosphorylation of GDI1 by CPK3 was required for the developmental modulation in Arabidopsis. PMID:23846874

  20. Protection of Chloroplast Membranes by VIPP1 Rescues Aberrant Seedling Development in Arabidopsis nyc1 Mutant

    Directory of Open Access Journals (Sweden)

    Lingang eZhang

    2016-04-01

    Full Text Available Chlorophylls (Chl in photosynthetic apparatuses, along with other macromolecules in chloroplasts, are known to undergo degradation during leaf senescence. Several enzymes involved in Chl degradation, by which detoxification of Chl is safely implemented, have been identified. Chl degradation also occurs during embryogenesis and seedling development. Some genes encoding Chl degradation enzymes such as Chl b reductase (CBR function during these developmental stages. Arabidopsis mutants lacking CBR (NYC1 and NOL reportedly exhibit reduced seed storability and compromised germination and cotyledon development. This study examined aberrant cotyledon development, finding that NYC1 is solely responsible for this phenotype. We inferred that oxidative damage of chloroplast membranes caused the aberrant cotyledon. To test the inference, we attempted to trans-complement nyc1 mutant with overexpressing VIPP1 protein that is unrelated to Chl degradation but which supports chloroplast membrane integrity. VIPP1 expression actually complemented the aberrant cotyledon of nyc1, whereas stay-green phenotype during leaf senescence remained. The swollen chloroplasts observed in unfixed cotyledons of nyc1, which are characteristics of chloroplasts receiving envelope membrane damage, were recovered by overexpressing VIPP1. These results suggest that chloroplast membranes are a target for oxidative damage caused by the impairment in Chl degradation. Trans-complementation of nyc1 with VIPP1 also suggests that VIPP1 is useful for protecting chloroplasts against oxidative stress.

  1. Effect of Agroforestry Residues Partially Biodegraded by Pleurotus Ostreatus (Pleurotaceae on Tomato Seedlings Development

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Luna Fontalvo

    2013-05-01

    Full Text Available It was evaluated the development of tomato seedlings (plant bioindicator of toxicity in soils with sawdust and rice husk partially biodegraded by Pleurotus Ostreatus in greenhouse conditions. Both organic compounds (carbon, cellulose, lignin, extractives, and organic matter, and inorganic compounds (nitrogen, phosphorus and pH were determined, before and after fungus inoculation on sawdust and rice husk. Mixtures were held of each substrate with a nutrient poor soil in equal proportions (1:1 and the moisture content was determined. The experiment consisted of a completely randomized, with two groups of six treatments for each substrate, and 30 days later, parameters of growth and development were identified. Biodegradedsubstrates presented low C, N and P. BSA + SF treatment (biodegraded sawdust + fertilized soil presented the best results in the number of leaves (12.9, plant height (25.94 cm, root length (5.92 cm, dry weight (0.138 g, and fresh weight (1.012 g. BSA + SF substrate can work as favorable substrate for growing tomato seedlings, BSA + SF substrate can work as favorable substrate for growing of tomato seedlings, since it provides the nutrients necessary for a good growth. Plants in rice bran did not grow adequately for transplanting.EFECTO DE RESIDUOS AGROFORESTALES PARCIALMENTE BIODEGRADADOS POR Pleurotus Ostreatus (PLEUROTACEAE SOBRE EL DESARROLLO DE PLÁNTULAS DE TOMATESe evaluó el desarrollo de plántulas de tomate (planta bioindicadora de toxicidad en suelos con aserrín y cascarilla de arroz parcialmente biodegradados por Pleurotus Ostreatus bajo condiciones de invernadero. Se determinaron los componentes orgánicos (carbono, celulosa, lignina, extraíbles y materia orgánica e inorgánicos (nitrógeno, fósforo y pH antes y después de inocular el hongo en el aserrín y la cascarilla de arroz. Se realizaron mezclas de cada sustrato con un suelo pobre en nutrientes en proporciones iguales (1:1 y se les determin

  2. Two members of the Ustilago maydis velvet family influence teliospore development and virulence on maize seedlings.

    Science.gov (United States)

    Karakkat, Brijesh B; Gold, Scott E; Covert, Sarah F

    2013-12-01

    Members of the fungal-specific velvet protein family regulate sexual and asexual spore production in the Ascomycota. We predicted, therefore, that velvet homologs in the basidiomycetous plant pathogen Ustilago maydis would regulate sexual spore development, which is also associated with plant disease progression in this fungus. To test this hypothesis, we studied the function of three U. maydis velvet genes, umv1, umv2 and umv3. Using a gene replacement strategy, deletion mutants were made in all three genes in compatible haploid strains, and additionally for umv1 and umv2 in the solopathogenic strain, SG200. None of the mutants showed novel morphological phenotypes during yeast-like, in vitro growth. However, the Δumv1 mutants failed to induce galls or teliospores in maize. Chlorazol black E staining of leaves infected with Δumv1 dikaryons revealed that the Δumv1 hyphae did not proliferate normally and were blocked developmentally before teliospore formation. The Δumv2 mutants were able to induce galls and teliospores in maize, but were slow to do so and thus reduced in virulence. The Δumv3 mutants were not affected in teliospore formation or disease progression. Complementation of the Δumv1 and Δumv2 mutations in the SG200 background produced disease indices similar to those of SG200. These results indicate that two U. maydis velvet family members, umv1 and umv2, are important for normal teliospore development and disease progression in maize seedlings.

  3. Myelopoiesis during Zebrafish Early Development

    Institute of Scientific and Technical Information of China (English)

    Jin Xu; Linsen Du; Zilong Wen

    2012-01-01

    Myelopoiesis is the process of producing all types of myeloid cells including monocytes/macrophages and granulocytes.Myeloid cells are known to manifest a wide spectrum of activities such as immune surveillance and tissue remodeling.Irregularities in myeloid cell development and their function are known to associate with the onset and the progression of a variety of human disorders such as leukemia.In the past decades,extensive studies have been carried out in various model organisms to elucidate the molecular mechanisms underlying myelopoiesis with the hope that these efforts will yield knowledge translatable into therapies for related diseases.Zebrafish has recently emerged as a prominent animal model for studying myelopoiesis,especially during early embryogenesis,largely owing to its unique properties such as transparent embryonic body and external development.This review introduces the methodologies used in zebrafish research and focuses on the recent research progresses of zebrafish myelopoiesis.

  4. Development of a biocrystallisation assay for examining effects of homeopathic preparations using cress seedlings

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    Jens-Otto Andersen

    2012-09-01

    Full Text Available Background: A major challenge of homeopathic basic research is to develop test systems that yield consistent results. Outcome of plant bioassays is usually based on growth parameters (e.g. germination rate, seedling length, leaf area. Aims: We aimed to evaluate the potential of a crystallisation method with additives (“biocrystallisation” as complementary outcome measure. This method used is based on the crystallographic phenomenon that when crystallising watery solutions of dihydrate CuCl2 in the presence of organic additives (juices/extracts, reproducible dendritic crystal structures are observed. The resulting biocrystallograms can be evaluated visually and/or by computerized image analysis. Methods: Cress seeds (Lepidium sativum L. germinated and grew in vitro in either Stannum met. 30x or water 30x. Per experiment, six coded (blinded 30x preparations were applied in randomized order, representing three independent replicates of the two treatments. Seedlings grew for 96 hours in darkness and were subsequently processed into a watery extract. Biocrystallisation was performed on circular glass plates in 6-fold replication per treatment group, yielding 36 biocrystallograms per experiment. A total of 15 independent experiments were performed at two independent laboratories. Biocrystallograms were scanned and analysed by computerized texture image analysis, using 15 second-order parameters as outcome measure. 3-way-ANOVA with the independent parameters treatment (n=2, internal replicate (n=3, and number of experiment (n=15 was used to analyse the data. Results: All 15 texture analysis variables yielded significant or highly significant results for the homeopathic treatment. Two variables yielded differences between the internal replicates, most probably due to a processing order effect. There were only minor differences between the results of the two laboratories. Conclusions

  5. Coordinated regulation of apical hook development by gibberellins and ethylene in etiolated Arabidopsis seedlings.

    Science.gov (United States)

    An, Fengying; Zhang, Xing; Zhu, Ziqiang; Ji, Yusi; He, Wenrong; Jiang, Zhiqiang; Li, Mingzhe; Guo, Hongwei

    2012-05-01

    Dark-grown Arabidopsis seedlings develop an apical hook when germinating in soil, which protects the cotyledons and apical meristematic tissues when protruding through the soil. Several hormones are reported to distinctly modulate this process. Previous studies have shown that ethylene and gibberellins (GAs) coordinately regulate the hook development, although the underlying molecular mechanism is largely unknown. Here we showed that GA(3) enhanced while paclobutrazol repressed ethylene- and EIN3-overexpression (EIN3ox)-induced hook curvature, and della mutant exhibited exaggerated hook curvature, which required an intact ethylene signaling pathway. Genetic study revealed that GA-enhanced hook development was dependent on HOOKLESS 1 (HLS1), a central regulator mediating the input of the multiple signaling pathways during apical hook development. We further found that GA(3) induced (and DELLA proteins repressed) HLS1 expression in an ETHYLENE INSENSITIVE 3/EIN3-LIKE 1 (EIN3/EIL1)-dependent manner, whereby EIN3/EIL1 activated HLS1 transcription by directly binding to its promoter. Additionally, DELLA proteins were found to interact with the DNA-binding domains of EIN3/EIL1 and repress EIN3/EIL1-regulated HLS1 expression. Treatment with naphthylphthalamic acid, a polar auxin transport inhibitor, repressed the constitutively exaggerated hook curvature of EIN3ox line and della mutant, supporting that auxin functions downstream of the ethylene and GA pathways in hook development. Taken together, our results identify EIN3/EIL1 as a new class of DELLA-associated transcription factors and demonstrate that GA promotes apical hook formation in cooperation with ethylene partly by inducing the expression of HLS1 via derepression of EIN3/EIL1 functions.

  6. Coordinated regulation of apical hook development by gibberellins and ethylene in etiolated Arabidopsis seedlings

    Institute of Scientific and Technical Information of China (English)

    Fengying An; Xing Zhang; Ziqiang Zhu; Yusi Ji; Wenrong He; Zhiqiang Jiang; Mingzhe Li; Hongwei Guo

    2012-01-01

    Dark-grown Arabidopsis seedlings develop an apical hook when germinating in soil,which protects the cotyledons and apical meristematic tissues when protruding through the soil.Several hormones are reported to distinctly modulate this process.Previous studies have shown that ethylene and gibberellins (GAs) coordinately regulate the hook development,although the underlying molecular mechanism is largely unknown.Here we showed that GA3 enhanced while paclobutrazol repressed ethylene- and EIN3-overexpression (EIN3ox)-induced hook curvature,and della mutant exhibited exaggerated hook curvature,which required an intact ethylene signaling pathway.Genetic study revealed that GA-enhanced hook development was dependent on HOOKLESS 1 (HLS1),a central regulator mediating the input of the multiple signaling pathways during apical hook development.We further found that GA3 induced (and DELLA proteins repressed) HLS1 expression in an ETHYLENE INSENSITIVE 3/EIN3-LIKE 1 (EIN3/EIL1)-dependent manner,whereby EIN3/EIL1 activated HLS1 transcription by directly binding to its promoter.Additionally,DELLA proteins were found to interact with the DNA-binding domains of EIN3/EIL1 and repress EIN3/EIL1-regulated HLS1 expression.Treatment with naphthylphthalamic acid,a polar auxin transport inhibitor,repressed the constitutively exaggerated hook curvature of EIN3ox line and della mutant,supporting that auxin functions downstream of the ethylene and GA pathways in hook development.Taken together,our results identify EIN3/EIL1 as a new class of DELLA-associated transcription factors and demonstrate that GA promotes apical hook formation in cooperation with ethylene partly by inducing the expression of HLS1 via derepression of EIN3/EIL1 functions.

  7. Glucose and auxin signaling interaction in controlling Arabidopsis thaliana seedlings root growth and development.

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    Bhuwaneshwar S Mishra

    Full Text Available BACKGROUND: Plant root growth and development is highly plastic and can adapt to many environmental conditions. Sugar signaling has been shown to affect root growth and development by interacting with phytohormones such as gibberellins, cytokinin and abscisic acid. Auxin signaling and transport has been earlier shown to be controlling plant root length, number of lateral roots, root hair and root growth direction. PRINCIPAL FINDINGS: Increasing concentration of glucose not only controls root length, root hair and number of lateral roots but can also modulate root growth direction. Since root growth and development is also controlled by auxin, whole genome transcript profiling was done to find out the extent of interaction between glucose and auxin response pathways. Glucose alone could transcriptionally regulate 376 (62% genes out of 604 genes affected by IAA. Presence of glucose could also modulate the extent of regulation 2 fold or more of almost 63% genes induced or repressed by IAA. Interestingly, glucose could affect induction or repression of IAA affected genes (35% even if glucose alone had no significant effect on the transcription of these genes itself. Glucose could affect auxin biosynthetic YUCCA genes family members, auxin transporter PIN proteins, receptor TIR1 and members of a number of gene families including AUX/IAA, GH3 and SAUR involved in auxin signaling. Arabidopsis auxin receptor tir1 and response mutants, axr2, axr3 and slr1 not only display a defect in glucose induced change in root length, root hair elongation and lateral root production but also accentuate glucose induced increase in root growth randomization from vertical suggesting glucose effects on plant root growth and development are mediated by auxin signaling components. CONCLUSION: Our findings implicate an important role of the glucose interacting with auxin signaling and transport machinery to control seedling root growth and development in changing nutrient

  8. A seedling specific vegetative lectin gene is related to development in Cicer arietinum.

    Science.gov (United States)

    Esteban, Rocío; Dopico, Berta; Muñoz, Francisco J; Romo, Silvia; Labrador, Emilia

    2002-04-01

    Plant lectins are a group of glycoproteins with the ability to recognize and bind carbohydrate ligands. Seed lectins function as storage and defense proteins, but the specific function of vegetative lectins is uncertain. In this paper we describe the characterization of a clone, CanVLEC, encoding a vegetative lectin from chickpea (Cicer arietinum L. cv. Castellana). The expression of the CanVLEC gene was specific in seedlings, mostly in hooks and elongating epicotyls, and no expression was detected in adult plants. The level of chickpea vegetative lectin transcripts in epicotyls decreased through the epicotyl growth suggesting a relationship to development. Treatment with indoleacetic acid (IAA) and brassinolides (BR), hormones that promoted elongation in chickpea epicotyl, increased the level of CanVLEC mRNA, supporting a relationship to growth. CanVLEC is drastically down regulated by water deficit ruling out its possible involvement in plant response to water stress, unlike other vegetative lectins. CanVLEC protein may be targeted to an extracellular location owing to the presence of a signal peptide.

  9. Effect of seed mass on emergence and seedling development in Ptero-carpus marsupium Roxb

    Institute of Scientific and Technical Information of China (English)

    Yogeshwar Mishra; Rimi Rawat; P.K.Rana; M.K.Sonkar; Naseer Mohammad

    2014-01-01

    We investigated the effect of seed mass on emergence, seed-ling survival and growth of Pterocarpus marsupium Roxb., a medium to large, commercially valuable and deciduous tree species. Among the three size classes viz. small (10-12 mm), medium (13-15 mm) and large (16-17 mm), the maximum proportion of seed by number (54.12%) and dry weight (51.87%) was recorded in the medium size seed class. Seed length and seed width were greatest in the large seed class (16.50 mm, 7.33 mm) followed by medium (13.50 mm, 5.60 mm) and small (11.37 mm, 3.66 mm). Similarly, hundred seed weight (100 sw) varied from a maximum of 12.92 g in the large seed class to intermediate 10.95 g in the medium seed class and minimum of 7.02 g in the small seed class. The large seed size showed maximum emergence and shoot length over the medium and small seed class. After six months of growth, significant variations due to seed size were also observed for the growth and dry weight of P. marsupium seedlings. Seedling vigour, expressed in terms of height, collar diameter, number of leaves and dry biomass, was sig-nificantly affected by seed class. Seedlings that emerged from large seeds showed better growth and produced heavier seedlings as compared to medium and small seeds.

  10. An early response regulatory cluster induced by low temperature and hydrogen peroxide in seedlings of chilling-tolerant japonica rice

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    Jia Yulin

    2007-06-01

    Full Text Available Abstract Background Plants respond to low temperature through an intricately coordinated transcriptional network. The CBF/DREB-regulated network of genes has been shown to play a prominent role in freeze-tolerance of Arabidopsis through the process of cold acclimation (CA. Recent evidence also showed that the CBF/DREB regulon is not unique to CA but evolutionarily conserved between chilling-insensitive (temperate and chilling-sensitive (warm-season plants. In this study, the wide contrast in chilling sensitivity between indica and japonica rice was used as model to identify other regulatory clusters by integrative analysis of promoter architecture (ab initio and gene expression profiles. Results Transcriptome analysis in chilling tolerant japonica rice identified a subset of 121 'early response' genes that were upregulated during the initial 24 hours at 10°C. Among this group were four transcription factors including ROS-bZIP1 and another larger sub-group with a common feature of having as1/ocs-like elements in their promoters. Cold-induction of ROS-bZIP1 preceded the induction of as1/ocs-like element-containing genes and they were also induced by exogenous H2O2 at ambient temperature. Coordinated expression patterns and similar promoter architectures among the 'early response' genes suggest that they belong to a potential regulon (ROS-bZIP – as1/ocs regulatory module that responds to elevated levels of ROS during chilling stress. Cultivar-specific expression signatures of the candidate genes indicate a positive correlation between the activity of the putative regulon and genotypic variation in chilling tolerance. Conclusion A hypothetical model of an ROS-mediated regulon (ROS-bZIP – as1/ocs triggered by chilling stress was assembled in rice. Based on the current results, it appears that this regulon is independent of ABA and CBF/DREB, and that its activation has an important contribution in configuring the rapid responses of rice seedlings

  11. Nitric Oxide, Ethylene, and Auxin Cross Talk Mediates Greening and Plastid Development in Deetiolating Tomato Seedlings.

    Science.gov (United States)

    Melo, Nielda K G; Bianchetti, Ricardo E; Lira, Bruno S; Oliveira, Paulo M R; Zuccarelli, Rafael; Dias, Devisson L O; Demarco, Diego; Peres, Lazaro E P; Rossi, Magdalena; Freschi, Luciano

    2016-04-01

    The transition from etiolated to green seedlings involves the conversion of etioplasts into mature chloroplasts via a multifaceted, light-driven process comprising multiple, tightly coordinated signaling networks. Here, we demonstrate that light-induced greening and chloroplast differentiation in tomato (Solanum lycopersicum) seedlings are mediated by an intricate cross talk among phytochromes, nitric oxide (NO), ethylene, and auxins. Genetic and pharmacological evidence indicated that either endogenously produced or exogenously applied NO promotes seedling greening by repressing ethylene biosynthesis and inducing auxin accumulation in tomato cotyledons. Analysis performed in hormonal tomato mutants also demonstrated that NO production itself is negatively and positively regulated by ethylene and auxins, respectively. Representing a major biosynthetic source of NO in tomato cotyledons, nitrate reductase was shown to be under strict control of both phytochrome and hormonal signals. A close NO-phytochrome interaction was revealed by the almost complete recovery of the etiolated phenotype of red light-grown seedlings of the tomato phytochrome-deficient aurea mutant upon NO fumigation. In this mutant, NO supplementation induced cotyledon greening, chloroplast differentiation, and hormonal and gene expression alterations similar to those detected in light-exposed wild-type seedlings. NO negatively impacted the transcript accumulation of genes encoding phytochromes, photomorphogenesis-repressor factors, and plastid division proteins, revealing that this free radical can mimic transcriptional changes typically triggered by phytochrome-dependent light perception. Therefore, our data indicate that negative and positive regulatory feedback loops orchestrate ethylene-NO and auxin-NO interactions, respectively, during the conversion of colorless etiolated seedlings into green, photosynthetically competent young plants. © 2016 American Society of Plant Biologists. All Rights

  12. Development and evaluation of TDR probe for water rational management on substrates used in forest seedlings production

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    Lucas Masayuki Sato

    2009-04-01

    Full Text Available Time Domain Reflectometry (TDR is a reliable technique to estimate in situ moisture content in different types of materials using probes. The forest seedlings production implies in a comprehensive and empirical process of water management applied to the substrate used for cultivation in dibble-tube. This type of cultivation requires analysis of the physical characteristics of water and nutrients retention of the substrate. The main goal of this research was to develop and evaluate a TDR coaxial probe for rational management of water in the forest seedlings production. Initially, a physical validation of the probe was performed considering the following parameters: reflection coefficient, characteristic impedance and spatial sensitivity. Also, the performance of the probe was evaluated to estimate water content in laboratory conditions and we obtained a calibration curve for each type of porous material used. The results demonstrated the viability of TDR probes to estimate water content in soil and substrates.

  13. Accelerated development in Johnsongrass seedlings (Sorghum halepense) suppresses the growth of native grasses through size-asymmetric competition

    Science.gov (United States)

    Meckel, Heather; Reichmann, Lara G.; Polley, H. Wayne; Fay, Philip A.

    2017-01-01

    Invasive plant species often dominate native species in competition, augmenting other potential advantages such as release from natural enemies. Resource pre-emption may be a particularly important mechanism for establishing dominance over competitors of the same functional type. We hypothesized that competitive success of an exotic grass against native grasses is mediated by establishing an early size advantage. We tested this prediction among four perennial C4 warm-season grasses: the exotic weed Johnsongrass (Sorghum halepense), big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparius) and switchgrass (Panicum virgatum). We predicted that a) the competitive effect of Johnsongrass on target species would be proportional to their initial biomass difference, b) competitive effect and response would be negatively correlated and c) soil fertility would have little effect on competitive relationships. In a greenhouse, plants of the four species were grown from seed either alone or with one Johnsongrass neighbor at two fertilizer levels and periodically harvested. The first two hypotheses were supported: The seedling biomass of single plants at first harvest (50 days after seeding) ranked the same way as the competitive effect of Johnsongrass on target species: Johnsongrass competition from Johnsongrass than from native species. At final harvest, native plants growing with Johnsongrass attained between 2–5% of their single-plant non-root biomass, while Johnsongrass growing with native species attained 89% of single-plant non-root biomass. Fertilization enhanced Johnsongrass’ competitive effects on native species, but added little to the already severe competitive suppression. Accelerated early growth of Johnsongrass seedlings relative to native seedlings appeared to enable subsequent resource pre-emption. Size-asymmetric competition and resource-pre-emption may be a critical mechanism by which exotic invasive species displace functionally

  14. Effects of Various Mixed Salt-Alkaline Stress Conditions on Seed Germination and Early Seedling Growth of Leymus chinensis from Songnen Grassland of China

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    Jixiang LIN

    2014-06-01

    Full Text Available Soil salinization and alkalization always co-occur in grassland ecosystem, but little information exists concerning the mixed effects of salt-alkaline stresses on plants.Leymus chinensis is considered as one of the most promising grass species in Songnen Grassland of Northern China. In this study, we investigated the effects of 30 mixed salt-alkaline conditions (NaCl, Na2SO4, NaHCO3 and Na2CO3; pH 7.10-10.18 and salinity 50-250 mM on seed germination and seedling growth of L. chinensis. The results showed that germination percentage and rate were both decreased with increasing salinity and pH. Nongerminated seeds germinated well after being transferred to distilled water from treatment groups. Shoot and radicle growth were also affacted by salinity, pH and their interactions. However, radicle length decreased more markedly with increasing salinity and pH, and was strongly inhibited when pH reached 8.05. Stepwise regression analysis results showed that salinity was the dominant factor for seed germination under mixed salt-alkaline stress conditions. However, once radicle break through the seed coat, and pH changed into the dominant factor for seedling establishment. These results indicated that mixed salt-alkaline stresses had different impacts on germination and early seedling stages of L. chinensis. A better understanding of the germination and seedling processes should facilitate the effective utilization of this species under such complex environment.

  15. RRP41L, a putative core subunit of the exosome, plays an important role in seed germination and early seedling growth in Arabidopsis.

    Science.gov (United States)

    Yang, Min; Zhang, Bangyue; Jia, Jianheng; Yan, Chunxia; Habaike, Ayijiang; Han, Yuzhen

    2013-01-01

    In prokaryotic and eukaryotic cells, the 3'-5'-exonucleolytic decay and processing of RNAs are essential for RNA metabolism. However, the understanding of the mechanism of 3'-5'-exonucleolytic decay in plants is very limited. Here, we report the characterization of an Arabidopsis (Arabidopsis thaliana) transfer DNA insertional mutant that shows severe growth defects in early seedling growth, including delayed germination and cotyledon expansion, thinner yellow/pale-green leaves, and a slower growth rate. High-efficiency thermal asymmetric interlaced polymerase chain reaction analysis showed that the insertional locus was in the sixth exon of AT4G27490, encoding a predicted 3'-5'-exonuclease, that contained a conserved RNase phosphorolytic domain with high similarity to RRP41, designated RRP41L. Interestingly, we detected highly accumulated messenger RNAs (mRNAs) that encode seed storage protein and abscisic acid (ABA) biosynthesis and signaling pathway-related protein during the early growth stage in rrp41l mutants. The mRNA decay kinetics analysis for seed storage proteins, 9-cis-epoxycarotenoid dioxygenases, and ABA INSENSITIVEs revealed that RRP41L catalyzed the decay of these mRNAs in the cytoplasm. Consistent with these results, the rrp41l mutant was more sensitive to ABA in germination and root growth than wild-type plants, whereas overexpression lines of RRP41L were more resistant to ABA in germination and root growth than wild-type plants. RRP41L was localized to both the cytoplasm and nucleus, and RRP41L was preferentially expressed in seedlings. Altogether, our results showed that RRP41L plays an important role in seed germination and early seedling growth by mediating specific cytoplasmic mRNA decay in Arabidopsis.

  16. Auxin polar transport of etiolated epicotyls of ageotropum pea seedlings is not affected by gravistimulation: Relevance to automorphosis-like growth and development

    Science.gov (United States)

    Miyamoto, K.; Hoshino, T.; Takahashi, Y.; Ueda, J.

    Both true microgravity conditions in space STS-95 space experiment and simulated ones on a three-dimensional 3-D clinostat have been demonstrated to induce automorphosis in etiolated pea Pisum sativum L cv Alaska seedlings represented as epicotyl bending as well as changes in root growth direction and inhibition of hook formation and to alter the activities of auxin polar transport of epicotyls The fact that the application of inhibitors of auxin polar transport phenocopied automorphosis together with the result of detail kinetic analyses of epicotyl bending on the 3-D clinostat suggests that automorphosis of etiolated pea epicotyls is due to suppression of a negative gravitropic response on 1 g conditions and graviresponse of etiolated pea seedlings under 1 g conditions requires normal activities of auxin polar transport To study the role of auxin polar transport in graviresponse in early growth stage of etiolated pea seedlings effect of gravistimulation on auxin polar transport in epicotyls of Alaska pea seedlings was studied in comparison with that of the agravitropic pea mutant ageotropum seedlings Dry pea seeds whose embryo axes were set in a horizontal position referred to as horizontal position or an inclinational one to the gravity vector referred to as inclinational position allowed to germinate and grow in the dark for 2 5 days Epicotyls of etiolated Alaska pea seedlings grown under horizontal position showed negative gravitropisum due to relatively larger elongation in the proximal side to the cotyledons

  17. Endophytic bacteria in cacti seeds can improve the development of cactus seedlings.

    Science.gov (United States)

    M. Esther Puente; Ching Y. Li; Yoav Bashan

    2009-01-01

    A plant-bacterium association between the giant cardon cactus Pachycereus pringlei and endophytic bacteria help seedlings establish and grow on barren rock, This cactus, together with other desert plants, is responsible for weathering ancient lava flows in the Baja California Peninsula of Mexico.When cardon seeds are inoculated with endophytic...

  18. Seed development, seed germination and seedling growth in the R50 (sym16) pea mutant are not directly linked to altered cytokinin homeostasis.

    Science.gov (United States)

    Long, Chengli; Held, Mark; Hayward, Allison; Nisler, Jaroslav; Spíchal, Lukas; Neil Emery, R J; Moffatt, Barbara A; Guinel, Frédérique C

    2012-06-01

    R50 (sym16) is a pea nodulation mutant that accumulates cytokinin (CK) in its vegetative organs. Total CK content increases as the plant ages because of the low activity of the enzyme cytokinin oxidase/dehydrogenase (CKX) responsible for CK degradation. R50 exhibits a large seed with high relative water content, and its seedling establishes itself slowly. Whether these two traits are linked to abnormal CK levels was considered here. R50 was found to have a similar germination rate but a much slower epicotyl emergence than Sparkle, its wild-type (WT). At the onset of emergence, the starch grains in R50 cotyledons were larger than those of WT; furthermore, they did not degrade as fast as in WT because of low amylase activity. No differences between the pea lines were observed in the CK forms identified during seed embryogenesis. However, while CK content compared to that of WT was reduced early in R50 embryogenesis, it was elevated later on in its dry seeds where CKX activity was low, although CKX transcript abundance remained high. Transcripts of the two known PsCKX isoforms exhibited tissue- and development-specific profiles with no detectable PsCKX2 expression in cotyledons. There were more of both transcripts in R50 roots than in WT roots, but less of PsCKX2 than PsCKX1 in R50 shoots compared to WT shoots. Thus, although there is a definite CKX post-transcriptional defect in R50 dry seeds, an abnormal CK homeostasis is not the basis of the delay in R50 seedling establishment, which we linked to abnormal amylase activity early in development. Copyright © Physiologia Plantarum 2012.

  19. Responses of Caryopsis Germination, Seedling Emergence, and Development to Sand Water Content of Agropyron cristatum (L.) Gaertn. and Bromus inermis Leyss.

    Institute of Scientific and Technical Information of China (English)

    Hui-Ling YANG; Xuan-Wei ZHU; Ming DONG; Zhen-Ying HUANG; Zhi-Ping CAO

    2005-01-01

    Responses of caryopsis germination, seedling emergence, and development of Agropyron cristatum (L.) Gaertn. (Gramineae) and Bromus inermis Leyss. (Gramineae), two dominant perennial grasses in the Otindag Sandland of China, to different sand water content (SWC; 1%, 2%, 3%, 4%, 6%, 8%, 12%,16%, and 20%) were studied comparatively. The results showed that the germination responses of the two grasses to SWC were similar (i.e. caryopses could not germinate when the SWC was below 3%; at SWC ranging from 3% to 12%, the higher the SWC, the higher the germination percentage; and at a SWC of 12%20%, germination reached similarly high percentages). At a sand burial depth of 0.5 cm, the threshold of SWC for seedling emergence was 6% forA. cristatum and 8% forB. inermis; at 12%-20% SWC, the seedling emergence of both species reached similarly high percentages. The seedling growth responses of these two species to SWC gradients were different. For A. cristatum, the biomass of seedlings increased with SWC from 6% to 12%, and decreased with SWC from 12% to 20%. For B. inermis, the biomass of seedlings always increased with SWC from 8% to 20%. The results also showed that the seedlings of both species allocated more biomass to the roots with decreases in SWC. The SWC changes from April to October in natural microhabitats of both species suggested that the SWC may play an important role in caryopsis germination,seedling emergence, and the growth characteristics of the two grasses. The responses of caryopsis germination, seedling emergence, and the growth characteristics of these two species to SWC may determine their distribution patterns in the Otindag Sandland.

  20. Effects of Wet Tray Seedling in Shallow Water on Temperature in Tray and Growth and Development and Biological Characteristics of Tobacco Seedlings%浅水湿润托盘育苗对盘内温度及烤烟生长发育及生物学性状的影响

    Institute of Scientific and Technical Information of China (English)

    金祥; 田必文; 陈风雷; 温明霞; 罗贞宝; 龙胜贤

    2013-01-01

    [目的]探讨烤烟浅水湿润托盘育苗的优势,为其广泛应该提供理论依据.[方法]以漂浮育苗为对照,研究烤烟浅水湿润托盘育苗时盘内温度及烟苗生长状况.[结果]浅水湿润托盘盘内温度较漂浮育苗盘内温度高0.4℃,出苗率相当,苗龄、移栽期、单株苗重、根系情况等方面均优于漂浮育苗.用该技术所育烟苗素质较好,栽后还苗期短,烟株长势较为旺盛,有利于烟叶产量、质量的提高.另外,较少的育苗用水量,有利于缓解干旱地区烤烟育苗的用水压力,减少育苗成本.[结论]浅水湿润托盘育苗技术充分继承了漂浮育苗技术和托盘育苗技术的优点,在烤烟育苗中有着广阔的应用空间.%[Objective] The aim was to discuss the advantage of tobacco wet tray seedling in shallow water,to provide a theoretical basis for its application widely.[Method] Taking floating seedling as control,temperature in tray and tobacco seedlings growth status were stuaied of the wet tray seedling in shallow water were studied.[Result] Temperature of wet tray seedling in shallow water was higher than that of floating seedling by 0.4 ℃,their seedling emergence rate was considerable,seedling age,transplanting period,plant seedling weight,root system were better than that of floating seedling.The tobacco seedlings bred by this technology was good,their seedling stage was short after planting,their growth vigor was vigorous,so was favor of improving tobacco leaf yield and quality.What' s more,less water consumption of seedling was favor of relieving the water use pressure of tobacco seedling breeding in Arid regions,and reducing the seedling breeding cost.[Conclusion] Seedling technology of shallow water wet tray fully inherits the advantages of floating seedling technology and tray seedling technology,has the rapid development space during tobacco seedling.

  1. EFFECT OF ARBUSCULAR MYCORRHIZAL COLONIZATION ON EARLY GROWTH AND NUTRIENT CONTENT OF TWO PEAT­ SWAMP FOREST TREE SPECIES SEEDLINGS, Calophyllum hosei AND Ploiarium alternifolium

    Directory of Open Access Journals (Sweden)

    Maman Turjaman

    2006-03-01

    Full Text Available Tropical peat-swamp forests are one of  the largest near-surface reserves of terrestrial organic carbon,  but rnany peat-swamp forest tree species decreased due over-exploitation, forest fire and conversion of natural forests into agricultural lands. Among those species are slow-growing Calophyllum  hoseiand Ploiarium  alternifolium, two species are good for construction of boats, furniture, house building and considerable attention from pharmacological viewpoint for human healthly. This study was aimed at understanding the effects of arbuscular mycorrhizal (AM fungi on early growth of  C. hosei and P.alternifoliumunder greenhouse condition. Seedlings of C. hosei and P.alternifoliumwere inoculated with AM fungi: Glomus clarum and Glomus aggregatum ,or uninoculated under greenhouse condition during 6 months. AM colonization,   plant growth,  survival rate and  nutrient  content  (P, Zn  and B were measured. The percentage of C. hoseiand P.alternifolium ranged from 27-32% and 18-19%,  respectively. Both inoculated seedling species had greater plant  height, diameter, leaf number, shoot and root dry weight than control  seedlings.   Nutrient  content  of  inoculated  plants  were increased with AM colonization- Survival rates of  inoculated plants were higher (100%  than those of  control plants (67%. The results suggested that inoculation of AM fungi could improve the early growth of C. hoseiand P.alternifolium grown in tropical peat-swamp forest therefore  this finding has greater potential impact if this innovative technology applied in field scales which are socially acceptable, commercially profitable and environmentally friendly.

  2. Interaction between seed size and NaCl on germination and early seedling growth of some Turkish cultivars of chickpea (Cicer arietinum L.)

    Institute of Scientific and Technical Information of China (English)

    Muharrem KAYA; Gamze KAYA; Mehmet Demir KAYA; Mehmet ATAK; Sevil SAGLAM; Khalid Mahmood KHAWAR; Cemalettin Yasar CIFTCI

    2008-01-01

    Chickpea is an important food legume crop of Turkey and is largely grown for human consumption on low moisture or salt-affected soils.The objective of the study was to find the effects of NaCl stress at electrical conductivities of 4.5,8.6,12.7 and 16.3 dS/m and seed sizes (7,8 and 9 mm) on germination and early seedling growth of three popular chickpea cultivars (AKN-97,Gokce and Uzunlu-99).Mean frequency of germination,germination time,germination index,root length,shoot length and seedling fresh weight showed seed size-dependent responses of cultivars to salt stress.In general,small seeds germinated and grew more rapidly compared to medium and large seeds of the same cultivars against all levels of salt stress,with the best results in cultivar Uzunlu-99.No effect of NaCl treatments was observed on frequency of germination; however,a drastic decrease in early seedling growth was recorded at increased NaCl concentrations.Regression analysis results showed a significantly positive rela-tionship (P<0.01) between seed size and mean germination time,whereas a significantly negative relationship was recorded between seed size and germination index,root length,shoot length.Moreover,linear regression values apparently confirmed that increased seed size in each cultivar affected decreased germination index,root and shoot lengths with enhanced mean germination time.Thus,it was concluded that the use of small seeds could considerably reduce the production costs of chickpea in salt-affected soils.

  3. Modulation of ethylene responses by OsRTH1 overexpression reveals the biological significance of ethylene in rice seedling growth and development.

    Science.gov (United States)

    Zhang, Wei; Zhou, Xin; Wen, Chi-Kuang

    2012-06-01

    Overexpression of Arabidopsis Reversion-To-ethylene Sensitivity1 (RTE1) results in whole-plant ethylene insensitivity dependent on the ethylene receptor gene Ethylene Response1 (ETR1). However, overexpression of the tomato RTE1 homologue Green Ripe (GR) delays fruit ripening but does not confer whole-plant ethylene insensitivity. It was decided to investigate whether aspects of ethylene-induced growth and development of the monocotyledonous model plant rice could be modulated by rice RTE1 homologues (OsRTH genes). Results from a cross-species complementation test in Arabidopsis showed that OsRTH1 overexpression complemented the rte1-2 loss-of-function mutation and conferred whole-plant ethylene insensitivity in an ETR1-dependent manner. In contrast, OsRTH2 and OsRTH3 overexpression did not complement rte1-2 or confer ethylene insensitivity. In rice, OsRTH1 overexpression substantially prevented ethylene-induced alterations in growth and development, including leaf senescence, seedling leaf elongation and development, coleoptile elongation or curvature, and adventitious root development. Results of subcellular localizations of OsRTHs, each fused with the green fluorescent protein, in onion epidermal cells suggested that the three OsRTHs were predominantly localized to the Golgi. OsRTH1 may be an RTE1 orthologue of rice and modulate rice ethylene responses. The possible roles of auxins and gibberellins in the ethylene-induced alterations in growth were evaluated and the biological significance of ethylene in the early stage of rice seedling growth is discussed.

  4. 全自动玉米秧苗移栽机的研制与试验%Development and test of automatic corn seedling transplanter

    Institute of Scientific and Technical Information of China (English)

    石铁

    2015-01-01

    Corn paper pot seedling transplanting technology is a new type cultivation method that can effectively increase accumulated temperature, resist drought, prevent disasters and obtain high yields; issues such as low and unstable grain yield due to shortage of water resources, drought and frequent plant diseases and insect pests in spring dry farming conditions. Conventional corn paper pot seedling transplanting operations are conducted on a manual basis, which generates features such as large labor intensity, low working efficiency, poor working quality, low degree of standardization and farming seasons cannot be grasped and so forth; the conventional operations are not beneficial to large area production operation, which seriously restricts the promotion and application of corn paper pot seedling transplanting technology. Therefore, mechanized corn seedling transplanting is an imperative trend. At present, corn paper pot seedling transplanting technology and methods as well as relevant machinery equipment are not available. Existing transplanting machineries in Europe, US, Japan and South Korea are mainly used for flowers, vegetables and economic crops. As per planting methods, transplanting machineries can be divided into: clamp type transplanters, chain clamp type transplanters, hanging cup type transplanters, seedling-guiding tube type transplanters and flexible disc type transplanters. However, all of such transplanters have some defects that cannot be overcome. A new type of full-automatic paper pot corn seedling transplanter was researched and developed based on the research of integrating the advantages of pot seedling and bare-rooted seedling, the principle of flexible disc type transplanting in combination with automation control and hydraulically powered seedling collecting, seedling rejecting and seedling supplying mechanism. The transplanter is composed of a seedling transporting and selecting transmission case, an automatic seeding system, a

  5. EFFECTS OF PISOLITHUS TINCTORIUS AND LACCARIA FRATERNA ON THE GROWTH AND MYCORRfflZAL DEVELOPMENT OF PINUSPATULA SEEDLINGS

    Directory of Open Access Journals (Sweden)

    M. SUDHAKARA REDDY

    1995-01-01

    Full Text Available Vegetative inoculum of Pisolithus tinctorius and Laccariafraterna were inoculated to Pinuspatula seedlings grown in both steam sterilized and unsterilized shola soil. After 4 months of seedling growth, 10 seedlings from each treatment were harvested and various growth parameters were studied. Inoculation of these two fungi resulted in the production of ectomycorrhizas and increase in growth of P. patula seedlings when compared to uninoculated seedlings. Laccariafraterna inoculated seedlings showed more number of mycorrhizas than P. tinctorius inoculated seedlings at the end of one year. Both these fungi poorly colonized the root system in both soil treatments. There was no significant difference between these two fungi in improving the seedling growth in the nursery.

  6. Differential Proteomic Analysis of Leaf Development at Rice (Oryza sativa)Seedling Stage

    Institute of Scientific and Technical Information of China (English)

    SHAO Cai-hong; LIU Guang-rong; WANG Jing-yuan; YUE Cai-fei; LIN Wen-xiong

    2008-01-01

    To identify the function of differential expression proteins in different leaves of rice seedlings extracted from 2- to 5-leaf stages,the leaf proteins at the seedling stage of hybrid rice Shanyou 63 were studied by using the approach of plant proteomics,and those proteins were separated with two-dimensional electrophoresis (2-DE) and then analyzed with an imagemaster 2D Elite 5.0.The results showed that the 41 protein spots were detected differential expression,of which 17 new protein spots appeared after the 3-leaf stage,including 9 special protein spots,which were only detected at the 3-leaf stage.Thirteen protein spots increased first and then decreased in expression abundance gradually and finally even disappeared.For the other 11 protein spots,3 protein spots decreased,but 6 protein spots were opposite in expression abundance,however,2 protein spots expressed in an irregular pattern after the 2-leaf stage.Of the 41 differential leaf proteins,15 protein spots were identified by ESI-Q MS/MS and categorized into 4 groups of functions.The results indicated that proteins were the carders of the functions in cells,but were significantly influenced by the changes in cell function or intercellular environment;hence,the reason that caused the proteomic changes as mentioned earlier might be related to the occurrence of tillers at the rice seedling stage after the 3-leaf stage.

  7. Changes in soluble carbohydrates and related enzymes induced by low temperature during early developmental stages of quinoa (Chenopodium quinoa) seedlings.

    Science.gov (United States)

    Rosa, Mariana; Hilal, Mirna; González, Juan A; Prado, Fernando E

    2004-06-01

    Low temperature represents one of the principal limitations in species distribution and crop productivity. Responses to chilling include the accumulation of simple carbohydrates and changes in enzymes involved in their metabolism. Soluble carbohydrate levels and invertase, sucrose synthase (SS), sucrose-6-phosphate synthase (SPS) and alpha-amylase activities were analysed in cotyledons and embryonic axes of quinoa seedlings grown at 5 degrees C and 25 degrees C in the dark. Significant differences in enzyme activities and carbohydrate levels were observed. Sucrose content in cotyledons was found to be similar in both treatments, while in embryonic axes there were differences. Invertase activity was the most sensitive to temperature in both organs; however, SS and SPS activities appear to be less stress-sensitive. Results suggest that 1) metabolism in germinating perispermic seeds would be different from endospermic seeds, 2) sucrose futile cycles would be operating in cotyledons, but not in embryonic axes of quinoa seedlings under our experimental conditions, 3) low temperature might induce different regulatory mechanisms on invertase, SS and SPS enzymes in both cotyledons and embryonic axes of quinoa seedlings, and 4) low temperature rather than water uptake would be mainly responsible for the changes observed in carbohydrate and related enzyme activities.

  8. Seed reserve composition and mobilization during germination and early seedling establishment of Cereus jamacaru D.C. ssp. jamacaru (Cactaceae

    Directory of Open Access Journals (Sweden)

    Nara L.M. Alencar

    2012-09-01

    Full Text Available Cereus jamacaru, a Cactaceae found throughout northeast Brazil, is widely used as cattle food and as an ornamental and medicinal plant. However, there has been little information about the physiological and biochemical aspects involved in its germination. The aim of this study was to investigate its reserve mobilization during germination and early seedling growth. For this, C. jamacaru seeds were germinated in a growth chamber and collected at 0, 2, 4, 5, 6, 8 and 12 days after imbibition for morphological and biochemical analyses. Dry seeds had wrinkled seed coats and large, curved embryos. Lipids were the most abundant reserve, comprising approximately 55% and 65% of the dry mass for cotyledons and the hypocotylradicle axis, respectively. Soluble sugars and starch were the minor reserves, corresponding to approximately 2.2% of the cotyledons' dry mass, although their levels showed significant changes during germination. Soluble proteins corresponded to 40% of the cotyledons' dry mass, which was reduced by 81% at the final period of germination compared to dry seeds. C. jamacaru seed can be classified as an oil seed due to its high lipid content. Moreover, lipids were the main reserve mobilized during germination because their levels were strongly reduced after seed germination, while proteins were the second most utilized reserve in this process.Cereus jamacaru, uma cactácea encontrada comumente no nordeste brasileiro, é amplamente usada como planta forrageira e como ornamental e medicinal. No entanto, existem poucas informações sobre os aspectos fisiológicos e bioquímicos relacionados à sua germinação. O objetivo desse estudo foi avaliar a mobilização de reservas durante a germinação e o crescimento inicial de plântulas de C. jamacaru. Para isso, as sementes foram germinadas em câmaras de germinação e coletadas aos 0, 2, 4, 5, 6, 8 e 12 dias após a germinação para as análises fisiológicas e bioquímicas. As sementes

  9. Population Structure, Diversity and Trait Association Analysis in Rice (Oryza sativa L.) Germplasm for Early Seedling Vigor (ESV) Using Trait Linked SSR Markers.

    Science.gov (United States)

    Anandan, Annamalai; Anumalla, Mahender; Pradhan, Sharat Kumar; Ali, Jauhar

    2016-01-01

    Early seedling vigor (ESV) is the essential trait for direct seeded rice to dominate and smother the weed growth. In this regard, 629 rice genotypes were studied for their morphological and physiological responses in the field under direct seeded aerobic situation on 14th, 28th and 56th days after sowing (DAS). It was determined that the early observations taken on 14th and 28th DAS were reliable estimators to study ESV as compared to 56th DAS. Further, 96 were selected from 629 genotypes by principal component (PCA) and discriminate function analyses. The selected genotypes were subjected to decipher the pattern of genetic diversity in terms of both phenotypic and genotypic by using ESV QTL linked simple sequence repeat (SSR) markers. To assess the genetic structure, model and distance based approaches were used. Genotyping of 96 rice lines using 39 polymorphic SSRs produced a total of 128 alleles with the phenotypic information content (PIC) value of 0.24. The model based population structure approach grouped the accession into two distinct populations, whereas unrooted tree grouped the genotypes into three clusters. Both model based and structure based approach had clearly distinguished the early vigor genotypes from non-early vigor genotypes. Association analysis revealed that 16 and 10 SSRs showed significant association with ESV traits by general linear model (GLM) and mixed linear model (MLM) approaches respectively. Marker alleles on chromosome 2 were associated with shoot dry weight on 28 DAS, vigor index on 14 and 28 DAS. Improvement in the rate of seedling growth will be useful for identifying rice genotypes acquiescent to direct seeded conditions through marker-assisted selection.

  10. Population Structure, Diversity and Trait Association Analysis in Rice (Oryza sativa L. Germplasm for Early Seedling Vigor (ESV Using Trait Linked SSR Markers.

    Directory of Open Access Journals (Sweden)

    Annamalai Anandan

    Full Text Available Early seedling vigor (ESV is the essential trait for direct seeded rice to dominate and smother the weed growth. In this regard, 629 rice genotypes were studied for their morphological and physiological responses in the field under direct seeded aerobic situation on 14th, 28th and 56th days after sowing (DAS. It was determined that the early observations taken on 14th and 28th DAS were reliable estimators to study ESV as compared to 56th DAS. Further, 96 were selected from 629 genotypes by principal component (PCA and discriminate function analyses. The selected genotypes were subjected to decipher the pattern of genetic diversity in terms of both phenotypic and genotypic by using ESV QTL linked simple sequence repeat (SSR markers. To assess the genetic structure, model and distance based approaches were used. Genotyping of 96 rice lines using 39 polymorphic SSRs produced a total of 128 alleles with the phenotypic information content (PIC value of 0.24. The model based population structure approach grouped the accession into two distinct populations, whereas unrooted tree grouped the genotypes into three clusters. Both model based and structure based approach had clearly distinguished the early vigor genotypes from non-early vigor genotypes. Association analysis revealed that 16 and 10 SSRs showed significant association with ESV traits by general linear model (GLM and mixed linear model (MLM approaches respectively. Marker alleles on chromosome 2 were associated with shoot dry weight on 28 DAS, vigor index on 14 and 28 DAS. Improvement in the rate of seedling growth will be useful for identifying rice genotypes acquiescent to direct seeded conditions through marker-assisted selection.

  11. THE EFFECT OF INDUSTRIAL WATER ON THE GERMINATION OF SEEDS AND THE DEVELOPMENT OF SEEDLINGS OF PISUM SATIVUM L.

    OpenAIRE

    Liliana Cristina SOARE; Codruţa-Mihaela DOBRESCU; Liana Elena LASCU

    2011-01-01

    The aim of the research was to highlight the influence of industrial water on the germination of seeds and the development of seedlings of Pisum sativum L., so that the impact of these water on the plants may be assessed, in case of accidental spills. The analysis of polluted industrial water indicates the presence of Cr, Fe, Ni, Pb, Cd, Cu, and Zn concentrations higher than CMA, except Cd, which was below the detection limit, and Cu. On leaving the neutralization station, metal concentration...

  12. Impacts of Seedling Age on Early Rice Yield and Yield component Factors%不同秧龄对早稻产量及其构成因素的影响

    Institute of Scientific and Technical Information of China (English)

    詹文忠; 梅少华; 范向阳; 梅金安; 翟中兵; 刘诗晴; 张从德; 魏坦雄

    2012-01-01

    Using hybrid early rice Liangyou 302 as experiment material, the effects of seedling age on growth characteristics, breed features and yield performance of rice with transplanting and seedling throwing methods were studied. The results showed that there were the same performance tendencies in growth characteristics, breed features and yield performance between transplanting rice and seedling throwing rice. Early planting at suitable age had the advantages of premature and early maturity. The vegetative period of 20 days-seedlings prolonged 3~10 d and its mature period arrived 2~6 d ahead of time. There were very significant negative correlations between seedling age and effective panicles, total grain number and yield.%以杂交早稻两优302为试验材料,研究了不同秧龄在移栽和抛栽方式下的生长特点、生育特性及产量表现.结果表明,移栽和抛栽表现趋势相同,适龄早栽具有早发和早熟优势,秧龄20 d时大田营养生长期延长3~10d,早熟2~6 d;秧龄与有效穗数、每穗总粒数和产量均呈极显著的负相关.

  13. Understanding Early Sexual Development (For Parents)

    Science.gov (United States)

    ... Reading Is Your Child Too Busy? Helping Your Child Adjust to Preschool School Lunches Kids and Food: 10 Tips for Parents Healthy Habits for TV, Video Games, and the Internet Understanding Early Sexual Development KidsHealth > For Parents > Understanding Early Sexual Development Print ...

  14. Application of arbuscular mycorrhizal fungi with Pseudomonas aeruginosa UPMP3 reduces the development of Ganoderma basal stem rot disease in oil palm seedlings.

    Science.gov (United States)

    Sundram, Shamala; Meon, Sariah; Seman, Idris Abu; Othman, Radziah

    2015-07-01

    The effect of arbuscular mycorrhizal fungi (AMF) in combination with endophytic bacteria (EB) in reducing development of basal stem rot (BSR) disease in oil palm (Elaeis guineensis) was investigated. BSR caused by Ganoderma boninense leads to devastating economic loss and the oil palm industry is struggling to control the disease. The application of two AMF with two EB as biocontrol agents was assessed in the nursery and subsequently, repeated in the field using bait seedlings. Seedlings pre-inoculated with a combination of Glomus intraradices UT126, Glomus clarum BR152B and Pseudomonas aeruginosa UPMP3 significantly reduced disease development measured as the area under disease progression curve (AUDPC) and the epidemic rate (R L) of disease in the nursery. A 20-month field trial using similar treatments evaluated disease development in bait seedlings based on the rotting area/advancement assessed in cross-sections of the seedling base. Data show that application of Glomus intraradices UT126 singly reduced disease development of BSR, but that combination of the two AMF with P. aeruginosa UPMP3 significantly improved biocontrol efficacy in both nursery and fields reducing BSR disease to 57 and 80%, respectively. The successful use of bait seedlings in the natural environment to study BSR development represents a promising alternative to nursery trial testing in the field with shorter temporal assessment.

  15. STUDIES CONCERNING THE INFLUENCE OF BIODEGRADABLE SLOW-RELEASE FERTILIZER USE IN DEVELOPING THE CULTURE OF PETUNIA HYBRIDA SEEDLINGS

    Directory of Open Access Journals (Sweden)

    Mona Popa

    2012-12-01

    Full Text Available Our research on the use of slow-release biodegradable fertilizers were applied to Petunia hybrida seedlings of the variety “White Surfinia”. Thus after 10 days subculturing procedure was to apply fertilizers containing NKP24 biodegradable and made in the form of sticks and granules with six concentrations of starch (5%, 10%, 15%, 20%, 25% and 50% quantaties (4-5 grams/ 1 pot. For each pot with of 8 cm diameter, we prepared a mixture of peat and garden soil in a rate of 1:1. During the vegetation periods, morphological analyses were made regarding the development of Petunia hybrida, cv. “White Surfinia”plants: the length of shoots and number of shoot. Average values recorded from morphological determinations after 1 month of starting experiments on biofertilizers influence on growth and development the seedlings of Petunia was demonstrated that the optimal variant was the fertilizer V5 with -25% WF (wood flour to 50% concentration of biofertilizers NKP24 (for both form of sticks A-big and B-medium and for fertilizer form C- granular the V6 variant with -50% concentration of biofertilizers NKP24, the petunia stem was recorded maximum of 58.92 cm length .The research is part of an international project FP7/2008 with the title "Forest Resource Sustainability through Bio-Based-Composite Development" – FORBIOPLAST. Multiple aims of FORBIOPLAST project are the valorization of forest resources for the production of bio-based products.

  16. Seed germination and seedling development in the mango (Mangifera indica L.).

    Science.gov (United States)

    Corbineau, F; Kanté, M; Côme, D

    1986-09-01

    Mango (Mangifera indica L., cv Ruby) seeds taken from ripe fruit showed no dormancy. They germinated at temperatures between 5 and 40 degrees C, but germination was most rapid near the upper end of this range (25-40 degrees C). The fresh seeds had a high moisture content (85%, dry weight basis) and quickly died on dehydration. The optimal temperature for growth of the seedlings was close to 30 degrees C. High temperatures (40 degrees C) and temperatures below 15 degrees C were lethal. Growth of the stem occurred in successive flushes separated by rest periods. When the leaves of the preceding flush finished growing, the axis lengthened beneath the apical bud.

  17. The mitochondrion-located protein OsB12D1 enhances flooding tolerance during seed germination and early seedling growth in rice.

    Science.gov (United States)

    He, Dongli; Zhang, Hui; Yang, Pingfang

    2014-07-31

    B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo) proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1). OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding.

  18. The Mitochondrion-Located Protein OsB12D1 Enhances Flooding Tolerance during Seed Germination and Early Seedling Growth in Rice

    Directory of Open Access Journals (Sweden)

    Dongli He

    2014-07-01

    Full Text Available B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1. OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding.

  19. Starch bioengineering affects cereal grain germination and seedling establishment

    DEFF Research Database (Denmark)

    Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...

  20. Effects of untreated and treated oilfield-produced water on seed germination, seedling development, and biomass production of sunflower (Helianthus annuus L.).

    Science.gov (United States)

    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.

  1. Seedling mycorrhiza

    DEFF Research Database (Denmark)

    Rasmussen, Hanne Nina; Rasmussen, Finn N.

    2014-01-01

    mycobionts suggest a derivation from a pathogenic relationship, and sister group comparison offers little support for derivation from other mycorrhizal relationships. A combination of in situ sowings and molecular identification of seedling mycobionts has established that a broad range of fungi besides...

  2. Early adversity, neural development, and inflammation.

    Science.gov (United States)

    Chiang, Jessica J; Taylor, Shelley E; Bower, Julienne E

    2015-12-01

    Early adversity is a risk factor for poor mental and physical health. Although altered neural development is believed to be one pathway linking early adversity to psychopathology, it has rarely been considered a pathway linking early adversity to poor physical health. However, this is a viable pathway because the central nervous system is known to interact with the immune system via the hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS). In support of this pathway, early adversity has been linked to changes in neural development (particularly of the amygdala, hippocampus, and prefrontal cortex), HPA axis and ANS dysregulation, and higher levels of inflammation. Inflammation, in turn, can be detrimental to physical health when prolonged. In this review, we present these studies and consider how altered neural development may be a pathway by which early adversity increases inflammation and thus risk for adverse physical health outcomes.

  3. Allelopathic effects of water extracts of Sorghum halepense (L. Pers., Convolvulus arvensis L. and Cirsium arvense Scop. on early seedling growth of some leguminous crops

    Directory of Open Access Journals (Sweden)

    Irena Golubinova

    2014-03-01

    Full Text Available In order to study the allelopathic effect of aboveground dry biomass of Sorghum halepense, Convolvulus arvensis and Cirsium arvense on seed germination and early seedling growth of Pisum sativum (L., varieties Mir (winter form and Kerpo (spring form; Vicia sativa (L., variety Tempo, and Medicago sativa (L., variety Dara, a laboratory experiment was conducted at the Institute of Forage Crops - Pleven. Four concentrations: 1.25, 2.5, 5.0 and 10.0% were applied to each weed biotype used to study allelopathic effects. The results showed that weed extracts significantly decreased germination percentage, shoot and root length (cm, shoot and root weight (g, and seed vigor index (SVI1 and SVI2 of the tested species. In general, the variable effects are related to the weed species and extract concentrations.

  4. Moral Development Interventions in Early Adolescence.

    Science.gov (United States)

    Enright, Robert D; And Others

    1983-01-01

    Strategies for promoting moral development in early adolescence reviewed include the "plus-one" model, Deliberate Psychological Education, didactic courses in social studies, and a high school Just Community on moral reasoning. (CJ)

  5. Performance of Jatropha curcas L. in Semi-arid Zone: Seed Germination, Seedling Growth and Early Field Growth

    Directory of Open Access Journals (Sweden)

    Sharif AHAMAD

    2013-05-01

    Full Text Available There is a lack of information on basic agronomic properties of Jatropha curcas L. (jatropha cultivation on the marginal lands in the semi-arids. Evaluation of agronomic performance of identified elite strains of J. curcas in marginal lands would be of paramount importance for addressing gap areas in their agronomic properties and subsequently for harnessing their optimum economic potentials. The present study undertook the task of analysing the growth performance of a high oil bearing elite strain of J. curcas–DARL-2 in degraded land in semi-arid zone of Deccan Plateau, India. While undertaking the assessment of growth performance of elite strain DARL-2, two other native (wild strains (namely AHN-1 and AHN-2 of J. curcas were also considered so that a comparative evaluation could be carried out. The role of gypsum was also investigated on J. curcas in the nursery stage as well its carry over effects on growth performance of transplanted trees in the field. Two types of substrates, gypsum-treated soil (GS and untreated soil (SL were used for growing seedlings of all the three jatropha strains. Seedlings (120-days-old of DARL-2 exhibited greater plant height, collar diameter and number of branches but root length was greater in the local strains. In the second year of field transplantation, DARL-2 strain exhibited significantly (p<0.05 greater plant height and number of branches/plant. No carry over effects of gypsum treatment were observed in field transplanted plants as none of the growth parameters significantly varied among the substrate types.

  6. Mycorrhizas on nursery and field seedlings of Quercus garryana.

    Science.gov (United States)

    Southworth, Darlene; Carrington, Elizabeth M; Frank, Jonathan L; Gould, Peter; Harrington, Connie A; Devine, Warren D

    2009-03-01

    Oak woodland regeneration and restoration requires that seedlings develop mycorrhizas, yet the need for this mutualistic association is often overlooked. In this study, we asked whether Quercus garryana seedlings in nursery beds acquire mycorrhizas without artificial inoculation or access to a mycorrhizal network of other ectomycorrhizal hosts. We also assessed the relationship between mycorrhizal infection and seedling growth in a nursery. Further, we compared the mycorrhizal assemblage of oak nursery seedlings to that of conifer seedlings in the nursery and to that of oak seedlings in nearby oak woodlands. Seedlings were excavated and the roots washed and examined microscopically. Mycorrhizas were identified by DNA sequences of the internal transcribed spacer region and by morphotype. On oak nursery seedlings, predominant mycorrhizas were species of Laccaria and Tuber with single occurrences of Entoloma and Peziza. In adjacent beds, seedlings of Pseudotsuga menziesii were mycorrhizal with Hysterangium and a different species of Laccaria; seedlings of Pinus monticola were mycorrhizal with Geneabea, Tarzetta, and Thelephora. Height of Q. garryana seedlings correlated with root biomass and mycorrhizal abundance. Total mycorrhizal abundance and abundance of Laccaria mycorrhizas significantly predicted seedling height in the nursery. Native oak seedlings from nearby Q. garryana woodlands were mycorrhizal with 13 fungal symbionts, none of which occurred on the nursery seedlings. These results demonstrate the value of mycorrhizas to the growth of oak seedlings. Although seedlings in nursery beds developed mycorrhizas without intentional inoculation, their mycorrhizas differed from and were less species rich than those on native seedlings.

  7. Germination and early plant development of 10 plant species exposed to Nano TiO2 and CeO2

    Science.gov (United States)

    Ten agronomic plant species were exposed to different concentrations of nano-TiO2 or CeO2 (0, 250, 500 and 1000 ug/l) and followed to examine effects on germination and early seedling development. For TiO2, cabbage showed increased and corn decreased percent germination, while ...

  8. Early development of visual recognition.

    Science.gov (United States)

    Plebe, Alessio; Domenella, Rosaria Grazia

    2006-01-01

    The most important ability of the human vision is object recognition, yet it is exactly the less understood aspect of the vision system. Computational models have been helpful in progressing towards an explanation of this obscure cognitive ability, and today it is possible to conceive more refined models, thanks to the new availability of neuroscientific data about the human visual cortex. This work proposes a model of the development of the object recognition capability, under a different perspective with respect to the most common approaches, with a precise theoretical epistemology. It is assumed that the main processing functions involved in recognition are not genetically determined and hardwired in the neural circuits, but are the result of interactions between epigenetic influences and the basic neural plasticity mechanisms. The model is organized in modules related with the main visual biological areas, and is implemented mainly using the LISSOM architecture, a recent self-organizing algorithm closely reflecting the essential behavior of cortical circuits.

  9. Influences of the Populus deltoids seedlings treated with exogenous methyl jasmonate on the growth and development of Lymantria dispar larvae

    Institute of Scientific and Technical Information of China (English)

    HU Zeng-hui; ZHAO Ling; YANG Di; SHEN Ying-bai; SHEN Fan-yi

    2006-01-01

    Lyantria dispar larvae were fed with the leaves of Populus deltoids seedlings exposed to methyl jasmonate (MeJA) for 24 h. The growth and development of the larvae were investigated, and phenolics contents in treated leaves including pyrocatechol, caffeic acid, coumarin, ferulic acid and benzoic acid were also surveyed by high-pressure liquid chromatography (HPLC). Results indicated that approximate digestibility, efficiency of conversion of ingested food, efficiency of conversion of digested food, and weight of the larvae were inhibited obviously, especially from the sixth day, which may result from the increase of total phenolics contents in treated leaves. This result provides strong supports for MeJA acting as the airborne signal molecule between woody plants.

  10. Early development of the aplacophoran mollusc Chaetoderma

    DEFF Research Database (Denmark)

    Nielsen, Claus; Haszprunar, Gerhard; Ruthensteiner, Bernhard;

    2007-01-01

    The early development of the trochophore larva of the aplacophoran Chaetoderma nitidulum (Mollusca: Caudofoveata = Chaetodermomorpha) is described using scanning and transmission electron microscopy and using fluorescence staining and confocal laser scanning microscopy of the muscle system...... of the early anlagen of the circular body wall muscles does not show the anterior-posterior mode of formation that is typical for annelids, thus strengthening the hypothesis of a non-segmented ancestry of Mollusca....

  11. Early Brain Development Research Review and Update

    Science.gov (United States)

    Schiller, Pam

    2010-01-01

    Thanks to imaging technology used in neurobiology, people have access to useful and critical information regarding the development of the human brain. This information allows them to become much more effective in helping children in their early development. In fact, when people base their practices on the findings from medical science research,…

  12. Early development of the human pelvic diaphragm

    NARCIS (Netherlands)

    Koch, Wijnandus Franciscus Robertus Maria

    2006-01-01

    The last decade an increasing interest in the pelvic floor can be observed in medical sciences. The lack of data on the development of the human pelvic floor is striking. The early development of the human pelvic diaphragm was studied. Materials and methods Use was made of 38 human embryos and fetus

  13. Early development of the human pelvic diaphragm

    NARCIS (Netherlands)

    Koch, Wijnandus Franciscus Robertus Maria

    2006-01-01

    The last decade an increasing interest in the pelvic floor can be observed in medical sciences. The lack of data on the development of the human pelvic floor is striking. The early development of the human pelvic diaphragm was studied. Materials and methodsUse was made of 38 human embryos and

  14. Teacher Knowledge Development in Early Field Experiences

    Science.gov (United States)

    Ingersoll, Casey; Jenkins, Jayne M.; Lux, Karen

    2014-01-01

    Investigation of physical education preservice teacher knowledge development has been primarily limited to study of a single semester of early field experience (EFE), with findings from these investigations driving EFE design. The purpose of this research was to investigate what types of knowledge develop and how knowledge evolves and interacts to…

  15. Early Brain Development Research Review and Update

    Science.gov (United States)

    Schiller, Pam

    2010-01-01

    Thanks to imaging technology used in neurobiology, people have access to useful and critical information regarding the development of the human brain. This information allows them to become much more effective in helping children in their early development. In fact, when people base their practices on the findings from medical science research,…

  16. Transcriptome Encyclopedia of Early Human Development.

    Science.gov (United States)

    Sahakyan, Anna; Plath, Kathrin

    2016-05-01

    Our understanding of human pre-implantation development is limited by the availability of human embryos and cannot completely rely on mouse studies. Petropoulos et al. now provide an extensive transcriptome analysis of a large number of human pre-implantation embryos at single-cell resolution, revealing previously unrecognized features unique to early human development.

  17. Allelopathic effects of leaf extracts of three agroforestry trees on germination and early seedling growth of wheat (Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Abdul Majeed

    2017-06-01

    Full Text Available Understanding of the growth promotory or inhibitory allelopathic effects of agroforestry trees on other plants is necessary for selection of suitable crops to be cultivated in their vicinity. In this experiment, aqueous leaf extracts of three agroforestry trees (Populus deltoides, Melia azedarach and Morus alba were evaluated on germination and seedling growth of wheat applied at concentration 1, 1.5, 2.0 and 2.5 g L-1 while distilled water was used as control treatment. Lower concentration of extracts (1 and 1.5 g L-1 of P. deltoides stimulated percent germination, root and stem height and dry biomass while higher concentration (2 and 2.5 g L-1 had no effect on these parameters. Mean germination time (MGT was not affected by the extract and its concentration. Aqueous extracts of M. azedarach and M. alba at concentration > 1 g L-1 significantly lowered the studied parameters except MGT which was significantly prolonged. Negative allelopathy was more evident at the highest aqueous extract concentration (2.5 g L-1 of the two trees. Extracts of M. alba were found more growth inhibitory than those of M. azedarach. The study suggests that lower concentration of leaf extracts of P. deltoides imparts stimulatory while M. azedarch and M. alba have negative allelopathic effects on wheat germination.

  18. The plastidic DEAD-box RNA helicase 22, HS3, is essential for plastid functions both in seed development and in seedling growth.

    Science.gov (United States)

    Kanai, Masatake; Hayashi, Makoto; Kondo, Maki; Nishimura, Mikio

    2013-09-01

    Plants accumulate large amounts of storage products in seeds to provide an energy reserve and to supply nutrients for germination and post-germinative growth. Arabidopsis thaliana belongs to the Brassica family, and oil is the main storage product in Arabidopsis seeds. To elucidate the regulatory mechanisms of oil biosynthesis in seeds, we screened for high density seeds (heavy seed) that have a low oil content. HS3 (heavy seed 3) encodes the DEAD-box RNA helicase 22 that is localized to plastids. The triacylglycerol (TAG) content of hs3-1 seeds was 10% lower than that of wild-type (WT) seeds, while the protein content was unchanged. The hs3-1 plants displayed a pale-green phenotype in developing seeds and seedlings, but not in adult leaves. The HS3 expression level was high in developing seeds and seedlings, but was low in stems, rosette leaves and flowers. The plastid gene expression profile of WT developing seeds and seedlings differed from that of hs3-1 developing seeds and seedlings. The expression of several genes was reduced in developing hs3-1 seeds, including accD, a gene that encodes the β subunit of carboxyltransferase, which is one component of acetyl-CoA carboxylase in plastids. In contrast, no differences were observed between the expression profiles of WT and hs3-1 rosette leaves. These results show that HS3 is essential for proper mRNA accumulation of plastid genes during seed development and seedling growth, and suggest that HS3 ensures seed oil biosynthesis by maintaining plastid mRNA levels.

  19. Direct detection of transcription factors in cotyledons during seedling development using sensitive silicon-substrate photonic crystal protein arrays.

    Science.gov (United States)

    Jones, Sarah I; Tan, Yafang; Shamimuzzaman, Md; George, Sherine; Cunningham, Brian T; Vodkin, Lila

    2015-03-01

    Transcription factors control important gene networks, altering the expression of a wide variety of genes, including those of agronomic importance, despite often being expressed at low levels. Detecting transcription factor proteins is difficult, because current high-throughput methods may not be sensitive enough. One-dimensional, silicon-substrate photonic crystal (PC) arrays provide an alternative substrate for printing multiplexed protein microarrays that have greater sensitivity through an increased signal-to-noise ratio of the fluorescent signal compared with performing the same assay upon a traditional aminosilanized glass surface. As a model system to test proof of concept of the silicon-substrate PC arrays to directly detect rare proteins in crude plant extracts, we selected representatives of four different transcription factor families (zinc finger GATA, basic helix-loop-helix, BTF3/NAC [for basic transcription factor of the NAC family], and YABBY) that have increasing transcript levels during the stages of seedling cotyledon development. Antibodies to synthetic peptides representing the transcription factors were printed on both glass slides and silicon-substrate PC slides along with antibodies to abundant cotyledon proteins, seed lectin, and Kunitz trypsin inhibitor. The silicon-substrate PC arrays proved more sensitive than those performed on glass slides, detecting rare proteins that were below background on the glass slides. The zinc finger transcription factor was detected on the PC arrays in crude extracts of all stages of the seedling cotyledons, whereas YABBY seemed to be at the lower limit of their sensitivity. Interestingly, the basic helix-loop-helix and NAC proteins showed developmental profiles consistent with their transcript patterns, indicating proof of concept for detecting these low-abundance proteins in crude extracts.

  20. Early and Late Rate of Force Development

    DEFF Research Database (Denmark)

    Andersen, Lars L; Andersen, Jesper L; Zebis, Mette K

    2010-01-01

    The objective of this study is to investigate the potentially opposing influence of qualitative and quantitative muscular adaptations in response to high-intensity resistance training on contractile rate of force development (RFD) in the early (200 ms) of rising muscle force. Fifteen healthy young...... the vastus lateralis. The main findings were that RFD in the late phase of rising muscle force increased in response to resistance training whereas early RFD remained unchanged and early relative RFD (i.e., RFD/MVC) decreased. Quantitatively, muscle fiber cross-sectional area and MVC increased whereas......-intensity resistance training due to differential influences of qualitative and quantitative muscular adaptations on early and later phases of rising muscle force....

  1. Maternal Effects on Seed and Seedling Phenotypes in Reciprocal F1 Hybrids of the Common Bean (Phaseolus vulgaris L.)

    Science.gov (United States)

    Singh, Jugpreet; Clavijo Michelangeli, Jose A.; Gezan, Salvador A.; Lee, Hyungwon; Vallejos, C. Eduardo

    2017-01-01

    Maternal control of seed size in the common bean provides an opportunity to study genotype-independent seed weight effects on early seedling growth and development. We set out to test the hypothesis that the early heterotrophic growth of bean seedlings is determined by both the relative amount of cotyledon storage reserves and the genotype of the seedling, provided the hybrid genotype could be fully expressed in the seedlings. The hypothesis was tested via comparison of seed weight and seedling growth phenotypes of small-seeded (wild, ~0.10 g) and large-seeded (landrace, ~0.55 g) parents and their reciprocal F1 hybrids. Akaike's Information Criteria were used to estimate growth parameters and identify the phenotypic model that best represented the data. The analysis presented here indicates that the hybrid embryo genotype is not fully expressed during both seed and seedling growth and development. The analysis presented here shows that seed growth and development are controlled by the sporophyte. The strong similarity in seed size and shape of the reciprocal hybrid seed with seeds of the maternal parents is evidence of this control. The analysis also indicates that since the maternal sporophyte controls seed size and therefore the amount of cotyledon reserves, the maternal sporophyte indirectly controls early seedling growth because the cotyledons are the primary nutrient source during heterotrophic growth. The most interesting and surprising results indicated that the maternal effects extended to the root architecture of the reciprocal hybrid seedlings. This phenomenon could not be explained by seed size, but by alterations in the control of the pattern of gene expression of the seedling, which apparently was set by a maternally controlled mechanism. Although seed weight increase was the main target of bean domestication, it also had positive repercussions on early-growth traits and stand establishment. PMID:28174586

  2. RFamide peptides in early vertebrate development

    Directory of Open Access Journals (Sweden)

    Guro Katrine Sandvik

    2014-12-01

    Full Text Available RFamides (RFa are neuropeptides involved in many different physiological processes in vertebrates, such as reproductive behavior, pubertal activation of the reproductive endocrine axis, control of feeding behavior, and pain modulation. As research has focused mostly on their role in adult vertebrates, the possible roles of these peptides during development are poorly understood. However, the few studies that exist show that RFa are expressed early in development in different vertebrate classes, perhaps mostly associated with the central nervous system. Interestingly, the related peptide family of FMRFa has been shown to be important for brain development in invertebrates. In a teleost, the Japanese medaka, knockdown of genes in the Kiss system indicates that Kiss ligands and receptors are vital for brain development, but few other functional studies exist. Here we review the literature of RFa in early vertebrate development, including the possible functional roles these peptides may play.

  3. Early executive function predicts reasoning development.

    Science.gov (United States)

    Richland, Lindsey E; Burchinal, Margaret R

    2013-01-01

    Analogical reasoning is a core cognitive skill that distinguishes humans from all other species and contributes to general fluid intelligence, creativity, and adaptive learning capacities. Yet its origins are not well understood. In the study reported here, we analyzed large-scale longitudinal data from the Study of Early Child Care and Youth Development to test predictors of growth in analogical-reasoning skill from third grade to adolescence. Our results suggest an integrative resolution to the theoretical debate regarding contributory factors arising from smaller-scale, cross-sectional experiments on analogy development. Children with greater executive-function skills (both composite and inhibitory control) and vocabulary knowledge in early elementary school displayed higher scores on a verbal analogies task at age 15 years, even after adjusting for key covariates. We posit that knowledge is a prerequisite to analogy performance, but strong executive-functioning resources during early childhood are related to long-term gains in fundamental reasoning skills.

  4. Early Phonological Development: Creating an Assessment Test

    Science.gov (United States)

    Stoel-Gammon, Carol; Williams, A. Lynn

    2013-01-01

    This paper describes a new protocol for assessing the phonological systems of two-year-olds with typical development and older children with delays in vocabulary acquisition. The test (Profiles of Early Expressive Phonological Skills ("PEEPS"), Williams & Stoel-Gammon, in preparation) differs from currently available assessments in…

  5. Computer simulation of early embryonic development

    NARCIS (Netherlands)

    Bezem, J.J.; Raven, Chr.P.

    1975-01-01

    A simple model, formulated in terms of elementary geometry, is presented, describing the early development of Lymnaea stagnalis. It includes the main morphogenetic processes active at this stage: cell division, cell flattening and differentiation. Though the model has been designed primarily to fit

  6. Nuclear phosphoproteome of developing chickpea seedlings (Cicer arietinum L.) and protein-kinase interaction network.

    Science.gov (United States)

    Kumar, Rajiv; Kumar, Amit; Subba, Pratigya; Gayali, Saurabh; Barua, Pragya; Chakraborty, Subhra; Chakraborty, Niranjan

    2014-06-13

    Nucleus, the control centre of eukaryotic cell, houses most of the genetic machineries required for gene expression and their regulation. Post translational modifications of proteins, particularly phosphorylation control a wide variety of cellular processes but its functional connectivity, in plants, is still elusive. This study profiled the nuclear phosphoproteome of a grain legume, chickpea, to gain better understanding of such event. Intact nuclei were isolated from 3-week-old seedlings using two independent methods, and nuclear proteins were resolved by 2-DE. In a separate set of experiments, phosphoproteins were enriched using IMAC method and resolved by 1-DE. The separated proteins were stained with phosphospecific Pro-Q Diamond stain. Proteomic analyses led to the identification of 107 putative phosphoproteins, of which 86 were non-redundant. Multiple sites of phosphorylation were predicted on several key elements, which included both regulatory and functional proteins. The analysis revealed an array of phosphoproteins, presumably involved in a variety of cellular functions, viz., protein folding (24%), signalling and gene regulation (22%), DNA replication, repair and modification (16%), and metabolism (13%), among others. These results represent the first nucleus-specific phosphoproteome map of a non-model legume, which would provide insights into the possible function of protein phosphorylation in plants. Chickpea is grown over 10 million hectares of land worldwide, and global production hovers around 8.5 million metric tons annually. Despite its nutritional merits, it is often referred to as 'orphan' legume and has remained outside the realm of large-scale functional genomics studies. While current chickpea genome initiative has primarily focused on sequence information and functional annotation, proteomics analyses are limited. It is thus important to study the proteome of the cell organelle particularly the nucleus, which harbors most of the genetic

  7. Physiological aspects of seedling development of coffee grown under colored screens; Aspectos fisiologicos do desenvolvimento de mudas de cafe cultivadas sob telas de diferentes coloracoes

    Energy Technology Data Exchange (ETDEWEB)

    Henrique, Paola de Castro; Alves, Jose Donizeti; Livramento, Darlan Einstein do, E-mail: jdalves@dbi.ufla.b, E-mail: delivramento@dbi.ufla.b [Universidade Federal de Lavras, MG (Brazil). Dept. de Biologia; Deuner, Sidnei, E-mail: sidnei.deuner@cpac.embrapa.b [EMBRAPA Cerrados, Planaltina, DF (Brazil); Goulart, Patricia de Fatima Pereira, E-mail: patriciagoulart@unilavras.edu.b [Centro Universitario de Lavras, MG (Brazil)

    2011-05-15

    The objective of this work was to evaluate the physiological aspects of the development of coffee seedlings grown under colored screens with different spectral characteristics. Seedlings of Catucai Amarelo 2SL, in the stage known as 'orelha de onca', were arranged in a randomized block design, with five replicates, under structures individually covered with blue, white, gray, black or red screens with 50% shade. Four months after, evaluations were done for seedling growth, pigment content of the leaves, total soluble sugars and starch contents of the leaves and roots. The red screen was the most effective in promoting growth in four out of the seven studied traits: plant height, leaf area and leaf dry weight and total dry matter. For the other characteristics, there was no difference among the screens. The pigment analysis showed that, except for the gray screen, the other ones did not differ for this trait. In leaves, the red screen promoted higher levels of carbohydrates and starch. At the root, carbohydrate contents were higher under the red and black screens. Among the five screen colors, the red one was the most efficient in the production of coffee seedlings with higher vigor and quality, with outstanding carbohydrate contents and biomass. (author)

  8. Laser light and magnetic field stimulation effect on biochemical, enzymes activities and chlorophyll contents in soybean seeds and seedlings during early growth stages.

    Science.gov (United States)

    Asghar, Tehseen; Jamil, Yasir; Iqbal, Munawar; Zia-Ul-Haq; Abbas, Mazhar

    2016-12-01

    Laser and magnetic field bio-stimulation attracted the keen interest of scientific community in view of their potential to enhance seed germination, seedling growth, physiological, biochemical and yield attributes of plants, cereal crops and vegetables. Present study was conducted to appraise the laser and magnetic field pre-sowing seed treatment effects on soybean sugar, protein, nitrogen, hydrogen peroxide (H2O2) ascorbic acid (AsA), proline, phenolic and malondialdehyde (MDA) along with chlorophyll contents (Chl "a" "b" and total chlorophyll contents). Specific activities of enzymes such as protease (PRT), amylase (AMY), catalyst (CAT), superoxide dismutase (SOD) and peroxides (POD) were also assayed. The specific activity of enzymes (during germination and early growth), biochemical and chlorophyll contents were enhanced significantly under the effect of both laser and magnetic pre-sowing treatments. Magnetic field treatment effect was slightly higher than laser treatment except PRT, AMY and ascorbic acid contents. However, both treatments (laser and magnetic field) effects were significantly higher versus control (un-treated seeds). Results revealed that laser and magnetic field pre-sowing seed treatments have potential to enhance soybean biological moieties, chlorophyll contents and metabolically important enzymes (degrade stored food and scavenge reactive oxygen species). Future study should be focused on growth characteristics at later stages and yield attributes.

  9. Nurturing care: promoting early childhood development.

    Science.gov (United States)

    Britto, Pia R; Lye, Stephen J; Proulx, Kerrie; Yousafzai, Aisha K; Matthews, Stephen G; Vaivada, Tyler; Perez-Escamilla, Rafael; Rao, Nirmala; Ip, Patrick; Fernald, Lia C H; MacMillan, Harriet; Hanson, Mark; Wachs, Theodore D; Yao, Haogen; Yoshikawa, Hirokazu; Cerezo, Adrian; Leckman, James F; Bhutta, Zulfiqar A

    2017-01-07

    The UN Sustainable Development Goals provide a historic opportunity to implement interventions, at scale, to promote early childhood development. Although the evidence base for the importance of early childhood development has grown, the research is distributed across sectors, populations, and settings, with diversity noted in both scope and focus. We provide a comprehensive updated analysis of early childhood development interventions across the five sectors of health, nutrition, education, child protection, and social protection. Our review concludes that to make interventions successful, smart, and sustainable, they need to be implemented as multi-sectoral intervention packages anchored in nurturing care. The recommendations emphasise that intervention packages should be applied at developmentally appropriate times during the life course, target multiple risks, and build on existing delivery platforms for feasibility of scale-up. While interventions will continue to improve with the growth of developmental science, the evidence now strongly suggests that parents, caregivers, and families need to be supported in providing nurturing care and protection in order for young children to achieve their developmental potential. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Early development and regression in Rett syndrome.

    Science.gov (United States)

    Lee, J Y L; Leonard, H; Piek, J P; Downs, J

    2013-12-01

    This study utilized developmental profiling to examine symptoms in 14 girls with genetically confirmed Rett syndrome and whose families were participating in the Australian Rett syndrome or InterRett database. Regression was mostly characterized by loss of hand and/or communication skills (13/14) except one girl demonstrated slowing of skill development. Social withdrawal and inconsolable crying often developed simultaneously (9/14), with social withdrawal for shorter duration than inconsolable crying. Previously acquired gross motor skills declined in just over half of the sample (8/14), mostly observed as a loss of balance. Early abnormalities such as vomiting and strabismus were also seen. Our findings provide additional insight into the early clinical profile of Rett syndrome.

  11. The developing hypopharyngeal microbiota in early life

    DEFF Research Database (Denmark)

    Mortensen, Martin Steen; Brejnrod, Asker Daniel; Roggenbuck, Michael

    2016-01-01

    BACKGROUND: The airways of healthy humans harbor a distinct microbial community. Perturbations in the microbial community have been associated with disease, yet little is known about the formation and development of a healthy airway microbiota in early life. Our goal was to understand the establi......BACKGROUND: The airways of healthy humans harbor a distinct microbial community. Perturbations in the microbial community have been associated with disease, yet little is known about the formation and development of a healthy airway microbiota in early life. Our goal was to understand...... the establishment of the airway microbiota within the first 3 months of life. We investigated the hypopharyngeal microbiota in the unselected COPSAC2010 cohort of 700 infants, using 16S rRNA gene sequencing of hypopharyngeal aspirates from 1 week, 1 month, and 3 months of age. RESULTS: Our analysis shows...

  12. On the biomechanics of seedling anchorage

    Science.gov (United States)

    Crouzy, Benoît; Edmaier, Katharina; Perona, Paolo

    2014-05-01

    We propose a minimal model for the response of vegetation to pullout constraints at early development stage. We try to capture both the average mechanical properties of the root system and the stochastic component of the uprooting process of seedlings. We identify a minimal set of relevant physical components in the purpose of quantifying the uprooting process: length of the root fibres, elastic response of the fibres and adhesion between the roots and the soil matrix. We present for validation a dataset extracted from Edmaier et al. (under revision), accounting for 98 uprooting experiments using Avena sativa L. seedlings (common oat), growing in non-cohesive sediment under controlled conditions. The corresponding root system has a very simple architecture, with three root fibres of different lengths. The response of the system to the constraint is however complex: the stress-strain signal presents sudden jumps followed by partial elastic recoveries. The analysis of the jumps and partial recoveries gives an insight into the resilience of the system. The anchorage of less mature seedlings rapidly collapses after the peak force has been reached, while more mature seedlings usually recover from partial failures. We explore this crossover with our validation dataset. The type of seedlings we study has been used in flume experiments investigating the feedbacks between the vegetation and the river morphodynamics (see for example Perona et al. (2012)). An understanding of the characteristics of the uprooting curve (maximal uprooting force and total uprooting work) of such vegetation reveals the ability of seedlings to withstand environmental constraints in terms of duration or intensity (see Edmaier et al., under revision), and is therefore helpful for planning future experiments. REFERENCES - P. Perona, P. Molnar, B. Crouzy, E. Perucca, Z. Jiang, S. McLelland, D. Wüthrich, K. Edmaier, R. Francis, C. Camporeale, et al., Biomass selection by floods and related timescales

  13. Cytoskeleton and Early Development in Fucoid Algae

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Cell polarization and asymmetric cell divisions play important roles during development in many multicellular eukaryotes.Fucoid algae have a long history as models for studying early developmental processes, probably because of the ease with which zygotes can be observed and manipulated in the laboratory. This review discusses cell polarization and asymmetric cell divisions in fucoid algal zygotes with an emphasis on the roles played by the cytoskeleton.

  14. QCD development in the early universe

    Energy Technology Data Exchange (ETDEWEB)

    Gromov, N. A., E-mail: gromov@dm.komisc.ru [Komi Science Center of the Ural Division of the Russian Academy of Sciences, Department of Mathematics (Russian Federation)

    2017-03-15

    The high-energy limit of Quantum Chromodynamics is generated by the contraction of its gauge groups. Contraction parameters are taken identical with those of the Electroweak Model and tend to zero when energy increases. At the infinite energy limit all quarks lose masses and have only one color degree of freedom. The limit model represents the development of Quantum Chromodynamics in the early Universe from the Big Bang up to the end of several milliseconds.

  15. [Effects nutrients on the seedlings root hair development and root growth of Poncirus trifoliata under hydroponics condition].

    Science.gov (United States)

    Cao, Xiu; Xia, Ren-Xue; Zhang, De-Jian; Shu, Bo

    2013-06-01

    Ahydroponics experiment was conducted to study the effects of nutrients (N, P, K, Ca, Mg, Fe, and Mn) deficiency on the length of primary root, the number of lateral roots, and the root hair density, length, and diameter on the primary root and lateral roots of Poncirus trifoliata seedlings. Under the deficiency of each test nutrient, root hair could generate, but was mainly concentrated on the root base and fewer on the root tip. The root hair density on lateral roots was significantly larger than that on primary root, but the root hair length was in adverse. The deficiency of each test nutrient had greater effects on the growth and development of root hairs, with the root hair density on primary root varied from 55.0 to 174.3 mm(-2). As compared with the control, Ca deficiency induced the significant increase of root hair density and length on primary root, P deficiency promoted the root hair density and length on the base and middle part of primary root and on the lateral roots significantly, Fe deficiency increased the root hair density but decreased the root hair length on the tip of primary root significantly, K deficiency significantly decreased the root hair density, length, and diameter on primary root and lateral roots, whereas Mg deficiency increased the root hair length of primary root significantly. In all treatments of nutrient deficiency, the primary root had the similar growth rate, but, with the exceptions of N and Mg deficiency, the lateral roots exhibited shedding and regeneration.

  16. Influence of microhabitat on seedling survival and growth of the mediterranean seagrass posidonia oceanica (l.) Delile

    Science.gov (United States)

    Alagna, Adriana; Fernández, Tomás Vega; Terlizzi, Antonio; Badalamenti, Fabio

    2013-03-01

    Early life history phases are crucial stages limiting species distribution and abundance, thus influencing assemblage composition in marine benthic environments. In seagrass systems the period between seed germination and establishment is one of the most vulnerable phases for plant development. This study analyzes the influence of microhabitat structure, in terms of substrate nature and algal canopy, on the persistence and growth over two years of seedlings of Posidonia oceanica, the dominant Mediterranean seagrass. Long time persistence of seedlings only occurred on microhabitats providing vegetated rocky substrates, with a maximum value of 81% on rock covered by Cystoseira spp. No seedling was found on unvegetated sand and gravel after the first year. Seedling growth resulted increased on rock covered by Halopteris spp. and Dilophus spp. than on rock covered by Cystoseira spp. Results suggest that high canopy onto a stable substrate enhances seedling persistence, probably because these allow the best anchorage by roots while hampering water flow. In contrast, turf algal cover promotes better seedling growth, possibly through higher light irradiance and nutrient availability. Our findings support the view that the understanding of the factors controlling early life processes is a necessary prerequisite for the comprehension of seagrass species distribution patterns, colonization and recovery potentials, which, in turn, can guide sound strategies for seagrass management and restoration.

  17. Expression of nebulette during early cardiac development.

    Science.gov (United States)

    Esham, Michael; Bryan, Kourtney; Milnes, Jennifer; Holmes, William B; Moncman, Carole L

    2007-04-01

    Nebulette, a cardiac homologue of nebulin, colocalizes with alpha-actinin in the pre-myofibrils of spreading cardiomyocytes and has been hypothesized to play a critical role in the formation of the thin-filament-Z-line complex early during myofibrillogenesis. Data from mesodermal explants or whole tissue mounts of developing hearts suggest that the pattern of myofibrillogenesis in situ may differ from observations of spreading cardiomyocytes. To evaluate the role of nebulette in myofibrillogenesis, we have analyzed the expression of nebulette in chicken heart rudiments by immunoblots and immunofluorescence. We detect the 110 kDa nebulette in heart rudiments derived from stage 9-10 using the anti-nebulin mAb, N114, or polyclonal anti-nebulette Abs by immunoblotting. Immunofluorescence analysis of explants stained with anti-nebulette and anti-alpha-actinin Abs demonstrates that both proteins localize along actin filaments in punctate to continuous manner at early stages of cardiac development and later give rise to striations. In both cases, the punctate staining had a periodicity of approximately 1.0 microm indicating a pre-myofibrils distribution at the earliest time points examined. We demonstrate that nebulette is indeed associated with premyofibrils in very early stages of myofibrillogenesis and suggest that nebulette may play an important role in the formation of these structures.

  18. Gene expression in plant lipid metabolism in Arabidopsis seedlings.

    Directory of Open Access Journals (Sweden)

    An-Shan Hsiao

    Full Text Available Events in plant lipid metabolism are important during seedling establishment. As it has not been experimentally verified whether lipid metabolism in 2- and 5-day-old Arabidopsis thaliana seedlings is diurnally-controlled, quantitative real-time PCR analysis was used to investigate the expression of target genes in acyl-lipid transfer, β-oxidation and triacylglycerol (TAG synthesis and hydrolysis in wild-type Arabidopsis WS and Col-0. In both WS and Col-0, ACYL-COA-BINDING PROTEIN3 (ACBP3, DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1 and DGAT3 showed diurnal control in 2- and 5-day-old seedlings. Also, COMATOSE (CTS was diurnally regulated in 2-day-old seedlings and LONG-CHAIN ACYL-COA SYNTHETASE6 (LACS6 in 5-day-old seedlings in both WS and Col-0. Subsequently, the effect of CIRCADIAN CLOCK ASSOCIATED1 (CCA1 and LATE ELONGATED HYPOCOTYL (LHY from the core clock system was examined using the cca1lhy mutant and CCA1-overexpressing (CCA1-OX lines versus wild-type WS and Col-0, respectively. Results revealed differential gene expression in lipid metabolism between 2- and 5-day-old mutant and wild-type WS seedlings, as well as between CCA1-OX and wild-type Col-0. Of the ACBPs, ACBP3 displayed the most significant changes between cca1lhy and WS and between CCA1-OX and Col-0, consistent with previous reports that ACBP3 is greatly affected by light/dark cycling. Evidence of oil body retention in 4- and 5-day-old seedlings of the cca1lhy mutant in comparison to WS indicated the effect of cca1lhy on storage lipid reserve mobilization. Lipid profiling revealed differences in primary lipid metabolism, namely in TAG, fatty acid methyl ester and acyl-CoA contents amongst cca1lhy, CCA1-OX, and wild-type seedlings. Taken together, this study demonstrates that lipid metabolism is subject to diurnal regulation in the early stages of seedling development in Arabidopsis.

  19. Cognitive theories of early gender development.

    Science.gov (United States)

    Martin, Carol Lynn; Ruble, Diane N; Szkrybalo, Joel

    2002-11-01

    The contribution of cognitive perspectives (cognitive-developmental theory and gender schema theory) to a contemporary understanding of gender development is evaluated. Recent critiques of cognitive approaches are discussed and empirical evidence is presented to counter these critiques. Because of the centrality of early gender development to the cognitive perspective, the latest research is reviewed on how infants and toddlers discriminate the sexes and learn the attributes correlated with sex. The essence of cognitive approaches--emphasis on motivational consequences of gender concepts; the active, self-initiated view of development; and focus on developmental patterns-is highlighted and contrasted with social-cognitive views. The value of cognitive theories to the field is illustrated, and recommendations are made concerning how to construct comprehensive, integrative perspectives of gender development.

  20. Photobiomodulation of early mouse embryo development

    Science.gov (United States)

    Sviridova-Chailakhyan, T. A.; Fakhranurova, L. I.; Simonova, N. B.; Khramov, R. N.; Manokhin, A. A.; Paskevich, S. I.; Chailakhyan, L. M.

    2008-04-01

    The effect of artificial sunlight (AS) from a xenon source and of converted AS with an additional orange-red luminescent (λ MAX=626 nm) component (AS+L) on the development of mouse zygotes was investigated. A plastic screen with a photoluminophore layer was used for production of this orange-red luminescent (L) component. A single short-term (15 min) exposure produced a long-term stable positive effect on early embryo development of mice, which persisted during several days. After exposure to AS+L, a stimulating influence on preimplantation development was observed, in comparison with the control group without AS exposure. The positive effects were as follows: increase in percent of embryos (P <= 0.05) developed to the blastocyst stage (96.2 %) with hatching from the zona pellucida (80.8 %) within 82-96 hours in vitro compared to the control (67.1 % and 28.8 %, respectively).

  1. ROCK inhibition prevents early mouse embryo development.

    Science.gov (United States)

    Duan, Xing; Chen, Kun-Lin; Zhang, Yu; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2014-08-01

    ROCK is a Rho-GTPase effector that is important for actin assembly and is involved in various cellular functions, including cell contraction, migration, motility, and tumor cell invasion. In this study, we investigated ROCK expression and function during early mouse embryo development. Inhibiting ROCK by Y-27632 treatment at the zygote stage resulted in first cleavage failure, and most embryos failed to develop to the 8-cell stage. When adding Y-27632 at the 8-cell stage, embryos failed to undergo compaction and could not develop into blastocysts. In addition, fluorescence staining intensity analysis indicated that actin expression at blastomere membranes was significantly reduced. After ROCK inhibition, two or more nuclei were observed in a cell, which indicated possible cytokinesis failure. Moreover, after ROCK inhibition with Y-27632, the phosphorylation levels of LIMK1/2, a downstream molecule of ROCK, were decreased at blastomere membranes. Thus, our results showed conserved roles for ROCK in this mammalian embryo model and indicated that a ROCK-LIMK1/2-actin pathway might regulate cleavage and blastocyst formation during early mouse embryo development.

  2. Roles of the haustorium and endosperm during the development of seedlings of Acrocomia aculeata (Arecaceae): dynamics of reserve mobilization and accumulation.

    Science.gov (United States)

    Mazzottini-Dos-Santos, Hellen Cássia; Ribeiro, Leonardo Monteiro; Oliveira, Denise Maria Trombert

    2016-11-24

    The mobilization of palm seed reserves is a complex process because of the abundance and diversity of stored compounds and results from the development of a highly specialized haustorium. This work focused on the important Neotropical oleaginous palm Acrocomia aculeata, with the aim of defining phases of seedling development associated with mobilization of reserves and elucidating the role of haustorium and endosperm in this process. Standard methods were performed, including biometric, anatomical, and histochemical analyses, as well as the evaluation of the activities of the enzymes endo-β-mannanase and lipase, throughout the reserve mobilization in seeds during germination and in seedlings. Seeds of A. aculeata stored large quantities of proteins, lipids, and polysaccharides in the embryo and endosperm. The mobilization of reserves initiated in the haustorium during germination and subsequently occurred in the endosperm adjacent to the haustorium, forming a gradually increasing zone of digestion. Proteins and polysaccharides were the first to be mobilized, followed by lipids and cell wall constituents. The haustorium activates and controls the mobilization, forming transitory reserves and translocating them to the vegetative axis, while the endosperm, which also has an active role, serves as a site of intense enzymatic activity associated with protein bodies. Seedling development can be described as occurring in six phases over a long period (approximately 150 days) due to the large amount of seed reserves. This process exhibits an alternation between stages of accumulation and translocation of protein, lipid, and carbohydrate reserves in the haustorium, which favors the seedling establishment and the reproductive success of the species.

  3. Seedling-herbivore interactions: insights into plant defence and regeneration patterns.

    Science.gov (United States)

    Barton, Kasey E; Hanley, Mick E

    2013-08-01

    Herbivores have the power to shape plant evolutionary trajectories, influence the structure and function of vegetation, devastate entire crops, or halt the spread of invasive weeds, and as a consequence, research into plant-herbivore interactions is pivotal to our understanding of plant ecology and evolution. However, the causes and consequences of seedling herbivory have received remarkably little attention, despite the fact that plants tend to be most susceptible to herbivory during establishment, and this damage can alter community composition and structure. In this Viewpoint article we review why herbivory during early plant ontogeny is important and in so doing introduce an Annals of Botany Special Issue that draws together the latest work on the topic. In a synthesis of the existing literature and a collection of new studies, we examine several linked issues. These include the development and expression of seedling defences and patterns of selection by herbivores, and how seedling selection affects plant establishment and community structure. We then examine how disruption of the seedling-herbivore interaction might affect normal patterns of plant community establishment and discuss how an understanding of patterns of seedling herbivory can aid our attempts to restore semi-natural vegetation. We finish by outlining a number of areas where more research is required. These include a need for a deeper consideration of how endogenous and exogenous factors determine investment in seedling defence, particularly for the very youngest plants, and a better understanding of the phylogenetic and biogeographical patterns of seedling defence. There is also much still be to be done on the mechanisms of seedling selection by herbivores, particularly with respect to the possible involvement of volatile cues. These inter-related issues together inform our understanding of how seedling herbivory affects plant regeneration at a time when anthropogenic change is likely to

  4. The effect of S-(ferrocenylmethyl-thiosalicylic acid sodium salt on the germination and growth of cereal grains and seedlings and on the development of pathogenic fungi

    Directory of Open Access Journals (Sweden)

    Jan Michalczyk

    2014-01-01

    Full Text Available The sodium salt of S-(ferrocenylmethyl-thiosalicylic acid was studied in the context of its possible use as a systemic fungicide and, concurrently, as a source of physiologically active iron fur crop plants. It was found that this metallocene was taken up by maize seedlings growing in liquid mediums, and used for chlorophyll synthesis, in a concentration range as low as 0.05-0.08 mM dm-3. In the concentration range of 0.05-1.5 mM dm-3, it inhibited germination, seedling growth and Y-amylase activity while it stimulated the activities of proteinases, catalase and peroxidase. When sprayed on cereal leaves at a concentration of 1.0-2.0 mM dm-3, it exhibited fungicidal properties: inhibition of fungus development without harming cereal plant leaves and stimulated chlorophyll synthesis.

  5. The developing hypopharyngeal microbiota in early life.

    Science.gov (United States)

    Mortensen, Martin Steen; Brejnrod, Asker Daniel; Roggenbuck, Michael; Abu Al-Soud, Waleed; Balle, Christina; Krogfelt, Karen Angeliki; Stokholm, Jakob; Thorsen, Jonathan; Waage, Johannes; Rasmussen, Morten Arendt; Bisgaard, Hans; Sørensen, Søren Johannes

    2016-12-30

    The airways of healthy humans harbor a distinct microbial community. Perturbations in the microbial community have been associated with disease, yet little is known about the formation and development of a healthy airway microbiota in early life. Our goal was to understand the establishment of the airway microbiota within the first 3 months of life. We investigated the hypopharyngeal microbiota in the unselected COPSAC2010 cohort of 700 infants, using 16S rRNA gene sequencing of hypopharyngeal aspirates from 1 week, 1 month, and 3 months of age. Our analysis shows that majority of the hypopharyngeal microbiota of healthy infants belong to each individual's core microbiota and we demonstrate five distinct community pneumotypes. Four of these pneumotypes are dominated by the genera Staphylococcus, Streptococcus, Moraxella, and Corynebacterium, respectively. Furthermore, we show temporal pneumotype changes suggesting a rapid development towards maturation of the hypopharyngeal microbiota and a significant effect from older siblings. Despite an overall common trajectory towards maturation, individual infants' microbiota are more similar to their own, than to others, over time. Our findings demonstrate a consolidation of the population of indigenous bacteria in healthy airways and indicate distinct trajectories in the early development of the hypopharyngeal microbiota.

  6. In vitro asymbiotic seed germination, mycorrhization and seedling development of Acampae praemorsa (Roxb.) Blatt. & Mc Cann, a common south Indian orchid

    Institute of Scientific and Technical Information of China (English)

    Kullaiyan Sathiyadash; Thangavelu Muthukumar; Shanmugaraj Bala Murugan; Ramalingam Sathishkumar; Eswaranpillai Uma; Sarah Jaison; Perumalsamy Priyadharsini

    2013-01-01

    Objective: To develope a conservation strategies for orchid species. Methods: Seeds of Acampae praemorsa (Roxb.) Blatt. Mc Cann (A. praemorsa) were obtained from mature pods collected from Velliangiri hills and germinated on Murashige and Skoog (MS) medium supplemented with various concentration of Benzylaminopurine (BAP). Results: Maximum seed germination (85%) was observed on MS media supplemented with 2 mg/LBAP. Seed germination percentage increased with increasing concentrations of BAP (0.5 mg/L to 2 mg/L), but 3 mg/L of BAP inhibited seed germination. Variations observed were significantly (P<0.01) different for concentrations of growth regulators, days and their interactions. The embryos in the seeds swelled prior to germination. Fifty days after inoculation, well developed greenish porotocorm like bodies (PLBs) were formed and by 80th day, 85% (maximum) of the PLBs were observed in MS supplemented with 2 mg/L BAP. Eighty days after seed sowing, the germination rate decreased and the PLBs were transformed into first and second leaf stages in media supplemented with Naphthaleneacetic acid (NAA). Maximum seedling numbers (84%) were observed in MS medium supplemented with 1 mg/L NAA at 110th day. After 110 days, the seedlings were transferred to 0.6 g/L MS medium containing activated charcoal and similar concentration of growth regulators for root induction. After rooting, the seedlings were transferred to ex vitro conditions. Conclusions: In present study all the mycorrhizal seedlings survived, because orchid mycorrhizal fungi enhance growth of orchid plantlets and present study gives an effective protocol for seed germination and plantlet regeneration from immature seeds which can be used for establishing A. praemorsa populations in Velliangiri Hills and elsewhere.

  7. Juvenile phase of seedling development in six Eurasian 5-needle Pine species: pattern and character of interspecific differences

    Directory of Open Access Journals (Sweden)

    A. G. Popov

    2013-12-01

    Full Text Available A species-specific trait system is formed as a result of two main factors: phylogenetic (origin, relationships and adaptive (environment within a modern natural habitat. Traits themselves also may be ranged by theirphylogenetic stability and adaptive value. Species are usually characterized by definitive traits. Meanwhile, ontogenetic traits may alsobe useful for understanding both species' phylogenesis and adaptation to climatic conditions. The purpose of the present study is toinvestigate the juvenile shoot structure in some Eurasian Pinus species from the section strobus. In the southern part of the WesternSiberian Plain forest zone, seedling growth and development were studied on six Eurasian species: stone pines (Pinus sibirica, P. cembra,P. pumila, P. koraiensis and white pines (P. parviflora, P. armandii. Shoot growth duration increases with an increase in vegetation season duration and the number of effective temperatures in the species' natural habitat: growth began slightly later, but it finished significantlylater. As far as shoot growth duration is concerned, the studied species were divided into 4 groups: (1 subarctic-subalpine P. pumila - 45-50 days, (2 boreal-mountain P. sibirica and P. cembra - 50-55 days, (3 nemoral from the monsoon forests P. koraiensis and P. parviflora - 60-65 days, (4 subtropical P. armandii - 75-80 days. The differences instructure and development of the juvenile shoots were not related to the climate in the natural habitat of species. On the basis of the juvenile morphogenesis duration and the presence of the mature organ type (5-needle short shoots on the juvenile shoot, three pairs ofspecies were distinguished: P. sibirica and P. cembra (1 year, do not have short shoots; P. koraiensis and P. armandii (1 year, shortshoots are present; P. parviflora and P. pumila (2 years, short shoots are present. It is shown that there is a close relationship between the species within

  8. Juvenile phase of seedling development in six Eurasian 5-needle Pine species: pattern and character of interspecific differences

    Directory of Open Access Journals (Sweden)

    A. G. Popov

    2013-12-01

    Full Text Available A species-specific trait system is formed as a result of two main factors: phylogenetic (origin, relationships and adaptive (environment within a modern natural habitat. Traits themselves also may be ranged by theirphylogenetic stability and adaptive value. Species are usually characterized by definitive traits. Meanwhile, ontogenetic traits may alsobe useful for understanding both species' phylogenesis and adaptation to climatic conditions. The purpose of the present study is toinvestigate the juvenile shoot structure in some Eurasian Pinus species from the section strobus. In the southern part of the WesternSiberian Plain forest zone, seedling growth and development were studied on six Eurasian species: stone pines (Pinus sibirica, P. cembra,P. pumila, P. koraiensis and white pines (P. parviflora, P. armandii. Shoot growth duration increases with an increase in vegetation season duration and the number of effective temperatures in the species' natural habitat: growth began slightly later, but it finished significantlylater. As far as shoot growth duration is concerned, the studied species were divided into 4 groups: (1 subarctic-subalpine P. pumila - 45-50 days, (2 boreal-mountain P. sibirica and P. cembra - 50-55 days, (3 nemoral from the monsoon forests P. koraiensis and P. parviflora - 60-65 days, (4 subtropical P. armandii - 75-80 days. The differences instructure and development of the juvenile shoots were not related to the climate in the natural habitat of species. On the basis of the juvenile morphogenesis duration and the presence of the mature organ type (5-needle short shoots on the juvenile shoot, three pairs ofspecies were distinguished: P. sibirica and P. cembra (1 year, do not have short shoots; P. koraiensis and P. armandii (1 year, shortshoots are present; P. parviflora and P. pumila (2 years, short shoots are present. It is shown that there is a close relationship between the species within

  9. Comparative analysis of gene expression at early seedling stage between a rice hybrid and its parents using a cDNA microarray of 9198 uni-sequences

    Institute of Scientific and Technical Information of China (English)

    HUANG; Yi; LI; Lihua; CHEN; Ying; LI; Xianghua; XU; Caiguo; WANG; Shiping; ZHANG; Qifa

    2006-01-01

    Using a cDNA microarray consisting of 9198 expressed sequence tags, we surveyed the gene expression profiles in shoots and roots of a rice hybrid, Liangyoupei 9 and its parents Peiai 64s and 93-11 at 72 h after germination. A total of 8587 sequences had detectable signals in both shoots and roots of the three genotypes. A total of 1571 sequences exhibited significant (P<0.01) expression differences in shoots or roots among the three genotypes, of which 121 showed expression polymorphisms in both shoots and roots, and 870 revealed significant expression differences between the hybrid and one of the parents. The expression polymorphism of the sequences was associated with the functional categories of the sequences. They occurred more frequently in categories of carbohydrate, energy and lipid metabolisms and stress response than expected, while less frequently in categories of amino acid metabolism, transcription and translation regulation, and signal transduction. A total of 214 sequences exhibited significant (P<0.05) mid-parent heterosis in expression, of which 117 had homology to genes with known functions, assigned in the categories of basic metabolism, genetic information processing, cell growth and death, signal transduction, transportation and stress response. The results may provide useful information for exploring the relationship between gene expression polymorphism and phenotypic variation, and for characterizing the molecular mechanism of seedling development and heterosis in rice.

  10. Development of a field inoculation method to screen for sugar beet seedling resistance to Fusarium oxysporum f. sp. beta

    Science.gov (United States)

    Fusarium yellows is an important disease in many sugar beet production areas throughout the U.S. and yield losses can be devastating. Also seedling damping off caused by Fusarium can result in serious damage to the sugar beet stand establishment. This can lead to a severe loss in yield. The object...

  11. Accelerated development in johnsongrass seedlings (Sorghum halepense) suppresses the growth of native grasses through size-asymmetric competition

    Science.gov (United States)

    Superior competitive ability is an expected characteristic of grassland invaders, but not all invaders exhibit traits that convey a persistent growth advantage. Here we examine priority, expressed as a brief seedling growth burst, as the driving mechanism through which the exotic weed Johnsongrass ...

  12. A comparative analysis of frog early development.

    Science.gov (United States)

    del Pino, Eugenia M; Venegas-Ferrín, Michael; Romero-Carvajal, Andrés; Montenegro-Larrea, Paola; Sáenz-Ponce, Natalia; Moya, Iván M; Alarcón, Ingrid; Sudou, Norihiro; Yamamoto, Shinji; Taira, Masanori

    2007-07-17

    The current understanding of Xenopus laevis development provides a comparative background for the analysis of frog developmental modes. Our analysis of development in various frogs reveals that the mode of gastrulation is associated with developmental rate and is unrelated to egg size. In the gastrula of the rapidly developing embryos of the foam-nesting frogs Engystomops coloradorum and Engystomops randi, archenteron and notochord elongation overlapped with involution at the blastopore lip, as in X. laevis embryos. In embryos of dendrobatid frogs and in the frog without tadpoles Eleutherodactylus coqui, which develop somewhat more slowly than X. laevis, involution and archenteron elongation concomitantly occurred during gastrulation; whereas elongation of the notochord and, therefore, dorsal convergence and extension, occurred in the postgastrula. In contrast, in the slow developing embryos of the marsupial frog Gastrotheca riobambae, only involution occurred during gastrulation. The processes of archenteron and notochord elongation and convergence and extension were postgastrulation events. We produced an Ab against the homeodomain protein Lim1 from X. laevis as a tool for the comparative analysis of development. By the expression of Lim1, we were able to identify the dorsal side of the G. riobambae early gastrula, which otherwise was difficult to detect. Moreover, the Lim1 expression in the dorsal lip of the blastopore and notochord differed among the studied frogs, indicating variation in the timing of developmental events. The variation encountered gives evidence of the modular character of frog gastrulation.

  13. Organ-specific rates of cellular respiration in developing sunflower seedlings and their bearing on metabolic scaling theory.

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J

    2012-10-01

    Fifty years ago Max Kleiber described what has become known as the "mouse-to-elephant" curve, i.e., a log-log plot of basal metabolic rate versus body mass. From these data, "Kleiber's 3/4 law" was deduced, which states that metabolic activity scales as the three fourths-power of body mass. However, for reasons unknown so far, no such "universal scaling law" has been discovered for land plants (embryophytes). Here, we report that the metabolic rates of four different organs (cotyledons, cotyledonary hook, hypocotyl, and roots) of developing sunflower (Helianthus annuus L.) seedlings grown in darkness (skotomorphogenesis) and in white light (photomorphogenesis) differ by a factor of 2 to 5 and are largely independent of light treatment. The organ-specific respiration rate (oxygen uptake per minute per gram of fresh mass) of the apical hook, which is composed of cells with densely packaged cytoplasm, is much higher than that of the hypocotyl, an organ that contains vacuolated cells. Data for cell length, cell density, and DNA content reveal that (1) hook opening in white light is caused by a stimulation of cell elongation on the inside of the curved organ, (2) respiration, cell density and DNA content are much higher in the hook than in the stem, and (3) organ-specific respiration rates and the DNA contents of tissues are statistically correlated. We conclude that, due to the heterogeneity of the plant body caused by the vacuolization of the cells, Kleiber's law, which was deduced using mammals as a model system, cannot be applied to embryophytes. In plants, this rule may reflect scaling phenomena at the level of the metabolically active protoplasmic contents of the cells.

  14. Design and Development of Aerogel-Based Antennas for Aerospace Applications: A Final Report to the NARI Seedling

    Science.gov (United States)

    Meador, Mary Ann B.; Miranda, Felix A.

    2014-01-01

    As highly porous solids possessing low density and low dielectric permittivity combined with good mechanical properties, polyimide (PI) aerogels offer great promise as an enabling technology for lightweight aircraft antenna systems. While they have been aggressively explored for thermal insulation, barely any effort has been made to leverage these materials for antennas or other applications that take advantage of their aforementioned attributes. In Phase I of the NARI Seedling Project, we fabricated PI aerogels with properties tailored to enable new antenna concepts with performance characteristics (wide bandwidth and high gain) and material properties (low density, environmental stability, and robustness) superior to the state of practice (SOP). We characterized electromagnetic properties, including permittivity, reflectivity, and propagation losses for the aerogels. Simple, prototype planar printed circuit patch antennas from down-selected aerogel formulations were fabricated by molding the aerogels to net shapes and by gold-metalizing the pattern onto the templates via electron beam evaporation in a clean room environment. These aerogel based antennas were benchmarked against current antenna SOP, and exhibited both broader bandwidth and comparable or higher gain performance at appreciably lower mass. Phase II focused on the success of the Phase I results pushing the PI aerogel based antenna technology further by exploring alternative antenna design (i.e., slot coupled antennas) and by examining other techniques for fabricating the antennas including ink jet printing with the goal of optimizing antenna performance and simplifying production. We also examined new aerogel formulations with better moisture and solvent resistance to survive processing conditions. In addition, we investigated more complex antenna designs including passive phased arrays such as 2x4 and 4x8 element arrays to assess the scalability of the aerogel antenna concept. Furthermore, we

  15. Seasonal variation of the effect of extremely diluted agitated gibberellic acid (10-30 on wheat seedling development

    Directory of Open Access Journals (Sweden)

    Peter Christian Endler

    2011-07-01

    Full Text Available Objective: Performing a study on a wheat growth bio assay with a homeopathic dilution of gibberellic acid at different seasons of the year. Methods: Grains of winter wheat (Triticum aestivum, Capo variety were observed under the influence of extremely diluted gibberellic acid (10-30, 30x. Analogously prepared water was used for control. 15 experiments were performed, 9 in autumn season (5 researchers, 4,440 grains per group, and 6 in winter / spring (4 researchers, with 3,140 grains per group. Results: All 9 autumn experiments showed less stalk growth in the verum group (p > 0.01 in 4 cases, p > 0.05 in 3, trend in 2 cases. Mean stalk lengths (mm were 46.97 + 20.50 for verum and 50.66 + 19.77 for control at grain level (N = 4,440 per group and + 3.87 and + 3.38 respectively at dish level (217 cohorts of 20 or 25 grains per treatment group. Verum stalk length (92.72% was 7.28% smaller than control stalk length (100%. In contrast, no reliable effect was found in experiments performed in winter / spring (less stalk growth in 1 case, no difference in 1, more growth in 3 cases. Overall verum stalk length (103.64% was 3.64% slightly greater than control stalk length (100%. Data were found to be homogeneous within the control groups as well as within the verum groups. Conclusion: Results suggest that especially in the experiments performed in autumn, there was an influence of gibberellic acid 30x on wheat seedling development. The effect size is small when calculation is done on the basis of grains (d = 0.18 but high when done on the basis of dishes (d = 1.02. In contrast, no reliable effect was found in experiments performed in winter / spring. Further experiments should thus be performed in the autumn season.

  16. Vegfa Impacts Early Myocardium Development in Zebrafish

    Science.gov (United States)

    Zhu, Diqi; Fang, Yabo; Gao, Kun; Shen, Jie; Zhong, Tao P.; Li, Fen

    2017-01-01

    Vascular endothelial growth factor A (Vegfa) signaling regulates cardiovascular development. However, the cellular mechanisms of Vegfa signaling in early cardiogenesis remain poorly understood. The present study aimed to understand the differential functions and mechanisms of Vegfa signaling in cardiac development. A loss-of-function approach was utilized to study the effect of Vegfa signaling in cardiogenesis. Both morphants and mutants for vegfaa display defects in cardiac looping and chamber formation, especially the ventricle. Vegfa regulates the heart morphogenesis in a dose-dependent manner. Furthermore, the initial fusion of the bilateral myocardium population is delayed rather than endocardium. The results demonstrate that Vegfa signaling plays a direct impact on myocardium fusion, indicating that it is the initial cause of the heart defects. The heart morphogenesis is regulated by Vegfa in a dose-dependent manner, and later endocardium defects may be secondary to impaired myocardium–endocardium crosstalk. PMID:28230770

  17. Vegfa Impacts Early Myocardium Development in Zebrafish

    Directory of Open Access Journals (Sweden)

    Diqi Zhu

    2017-02-01

    Full Text Available Vascular endothelial growth factor A (Vegfa signaling regulates cardiovascular development. However, the cellular mechanisms of Vegfa signaling in early cardiogenesis remain poorly understood. The present study aimed to understand the differential functions and mechanisms of Vegfa signaling in cardiac development. A loss-of-function approach was utilized to study the effect of Vegfa signaling in cardiogenesis. Both morphants and mutants for vegfaa display defects in cardiac looping and chamber formation, especially the ventricle. Vegfa regulates the heart morphogenesis in a dose-dependent manner. Furthermore, the initial fusion of the bilateral myocardium population is delayed rather than endocardium. The results demonstrate that Vegfa signaling plays a direct impact on myocardium fusion, indicating that it is the initial cause of the heart defects. The heart morphogenesis is regulated by Vegfa in a dose-dependent manner, and later endocardium defects may be secondary to impaired myocardium–endocardium crosstalk.

  18. Early development of the vertebral column.

    Science.gov (United States)

    Scaal, Martin

    2016-01-01

    The segmental organization of the vertebrate body is most obviously visible in the vertebral column, which consists of a series of vertebral bones and interconnecting joints and ligaments. During embryogenesis, the vertebral column derives from the somites, which are the primary segments of the embryonic paraxial mesoderm. Anatomical, cellular and molecular aspects of vertebral column development have been of interest to developmental biologists for more than 150 years. This review briefly summarizes the present knowledge on early steps of vertebral column development in amniotes, starting from sclerotome formation and leading to the establishment of the anatomical bauplan of the spine composed of vertebral bodies, vertebral arches, intervertebral discs and ribs, and their specific axial identities along the body axis.

  19. Development of 2ZP-3Type Rice Seedling Throwing Machine%2ZP-3型水稻抛秧机的研制

    Institute of Scientific and Technical Information of China (English)

    王继先; 潘兴吉吉

    2001-01-01

    The basic components,working principle and several key techniques in the development process of 2ZP-3 type rice seedling throwing machine were outlined in this paper.The field test indicated that the labor productivity was increased greatly,the labor intensity was reduced,very fewer rice seedlings were injuned,the machine's thrower was stable,and the seedlings were well-distributed,indicating this machine was useful and efficient for rice planting.%论述了2ZP-3型水稻抛秧机的基本组成和工作原理、研制过程中解决的几个关键技术问题以及田间试验结果。田间试验结果表明:该机大大提高了劳动生产率,减轻了劳动强度;关键部件抛射器运转稳定,伤苗少,适应多种秧苗的抛射作业,且秧苗田间分布均匀,满足农艺要求。该机是一种新型、实用、高效的水稻种植机械。

  20. Immunologically related lectins from stems and roots of developing seedlings of Cucurbita ficifolia: purification and some properties of root and stem lectins

    Directory of Open Access Journals (Sweden)

    Irena Lorenc-Kubis

    2014-02-01

    Full Text Available Hemagglutinating activity has been found in acetate extracts from roots and stems of squash seedlings (Cucurbita ficifolia. The hemaglutinating activity changes during seeds germination and seedling development. Dot blot and Western blot techniques have shown that proteins from these vegetative tissues cross-reacted with antibodies raised against endogenous cotyledons lectin CLBa and Con A.Lectins were isolated from stems and roots of 6-day old seedlings by precipitation with ethanol, affinity chromatography on Con A-Sepharose, gel filtration on Bio-gel P100 and separated by electrophoresis on polyacrylamide gel. Three purified lectins (RLA1, RLA2, RLA3 were obtained from roots and four from stems (SLA1, SLA2, SLA3, SLA4. The purified lectins from roots and stems agglutinated all human red blood cells, but sheep erythrocytes were most sensitive to agglutination. The hemagglutination of the root lectins RLA2 and RLA3 was inhibited by a very low concentration of arabinose, while RLA1, of xylose and Ga1NAc. Arabinose and Xylose were also found to be the most effective inhibitors of all stem lectins.

  1. Growth and Allocation of Dry Matter in Bean Seedlings Developed up to the Senescence of the Cotyledons

    Directory of Open Access Journals (Sweden)

    Ramón DÍaz-ruiz

    2008-12-01

    Full Text Available The allocation of dry matter in seedling of the common bean (Phaseolus vulgaris L. depends on the nutrient content in the cotyledons on principle of germination. The importance of these structures for the growth of the seedling ranges from the time of germination to the emergence of the seedling and the time when the simple leaves can realize photosynthesis. The objective of this research was to study and quantify the distribution of dry matter from the stage of germination until senescence of cotyledons during the seedling stage. Two experiments were conducted using the common bean variety Cacahuate-72, one in a greenhouse and another in growth chamber with a constant temperature of 25oC. To determine the dry weight of the structures sampling was carried out at different ages of the seedling. The stem accumulated more dry matter than the root, 56% and 44% respectively. The distribution of dry matter in the shoot structures was in the following order: simple leaves 60%, hypocotyl 25%, epicotyle 8%, petioles 5% and fi rst trifoliate leaf 2%. Root dry matter was distributed in the following order: secondary roots 46%, adventitious roots 42%, taproot 10% and tertiary roots 2%. The cotyledons exhausted its reserves of nutrients by the 18th day and they senesced at the same time. At the time of senescence of the cotyledons the hypocotyl structure was longer than the stem. Considering the root, secondary roots presented more length and were the most abundant in number. The input of fertilizer to the soil is necessary when cotyledons are beginning the process of senescence.

  2. Development of Life on Early Mars

    Science.gov (United States)

    Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

    2009-01-01

    Exploration of Mars has begun to unveil the history of the planet. Combinations of remote sensing, in situ compositional measurements and photographic observations have shown Mars had a dynamic and active geologic evolution. Mars geologic evolution encompassed conditions that were suitable for supporting life. A habitable planet must have water, carbon and energy sources along with a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water- as shown by carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001, well-dated at 3.9 Gy, (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, active volcanism continuing throughout Martian history, and continuing impact processes, (iii) Carbon, water and a likely thicker atmosphere from extensive volcanic outgassing (i.e. H20, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust [1]. The question arises: "Why would life not develop from these favorable conditions on Mars in its first 600 My?" During this period, environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would favor the formation of early life. (Even if life developed elsewhere on Earth, Venus, or on other bodies-it was transported to Mars where surface conditions were suitable for life to evolve). The commonly stated requirement that life would need hundreds of millions of year to get started is only an assumption; we know of no evidence that requires such a long interval for the development of life, if the proper habitable

  3. Cell fate regulation in early mammalian development

    Science.gov (United States)

    Oron, Efrat; Ivanova, Natalia

    2012-08-01

    Preimplantation development in mammals encompasses a period from fertilization to implantation and results in formation of a blastocyst composed of three distinct cell lineages: epiblast, trophectoderm and primitive endoderm. The epiblast gives rise to the organism, while the trophectoderm and the primitive endoderm contribute to extraembryonic tissues that support embryo development after implantation. In many vertebrates, such as frog or fish, maternally supplied lineage determinants are partitioned within the egg. Cell cleavage that follows fertilization results in polarization of these factors between the individual blastomeres, which become restricted in their developmental fate. In contrast, the mouse oocyte and zygote lack clear polarity and, until the eight-cell stage, individual blastomeres retain the potential to form all lineages. How are cell lineages specified in the absence of a maternally supplied blueprint? This is a fundamental question in the field of developmental biology. The answer to this question lies in understanding the cell-cell interactions and gene networks involved in embryonic development prior to implantation and using this knowledge to create testable models of the developmental processes that govern cell fates. We provide an overview of classic and contemporary models of early lineage development in the mouse and discuss the emerging body of work that highlights similarities and differences between blastocyst development in the mouse and other mammalian species.

  4. Early Literacy and Early Numeracy: The Value of Including Early Literacy Skills in the Prediction of Numeracy Development

    Science.gov (United States)

    Purpura, David J.; Hume, Laura E.; Sims, Darcey M.; Lonigan, Cristopher J.

    2011-01-01

    The purpose of this study was to examine whether early literacy skills uniquely predict early numeracy skills development. During the first year of the study, 69 3- to 5-year-old preschoolers were assessed on the Preschool Early Numeracy Skills (PENS) test and the Test of Preschool Early Literacy Skills (TOPEL). Participants were assessed again a…

  5. Germinación, emergencia y crecimiento temprano de arroz rojo y cuatro variedades de arroz Germination, emergence and early seedling growth of red rice and four rice cultivars

    Directory of Open Access Journals (Sweden)

    Clavijo P. Jairo

    1988-12-01

    weight of shoots and roots 10 days after emergence were recorded as characteristics of early seedling growth. In all cases, a significant difference between red rice and the four cultivars was found with red rice showing the highest value. When the shoots root ratio was calculated on a dry weight basis Saturn had the highest ratio followed by red rice. These results suggest that the rapid germination and emergence and early
    growth of both shoots and roots exhibited by red rice may contribute to its competitive ability by enabling it to preempt more resources at early stages of stand development.

  6. Communication and community development: early child development programs.

    Science.gov (United States)

    Wood, F; Reinhold, A J

    1993-01-01

    Community-based groups are organized around particular aspects of early childhood development (ECD), such as literacy, parent education, and early childhood activities. In the Colombian national program, community households call upon women to devote a portion of their home to organized child care for minimal material reward. The Indian Child Development Service subsidizes the payment of organizers; and Kenyan parents construct basic preschool facilities, provide school lunches, and subsidize a teacher. In such cases the government plays a subordinate role, while the burden of program maintenance is carried by the community. These programs share the characteristics that children and adults learn side by side; adult learning ranges from women's literacy, to health, organizational issues, or small-scale economic development; a strong cultural component emphasizes mother tongue language learning, indigenous child-rearing practices, and local working models; physical structures are in homes; capacity-building for the adults is central which will be transferred to other spheres of community life. In the remote coastal villages of Colombia, an organization called Promesa works with mothers on designing their preschool children's educational activities. Promesa began to confront other priority needs in the villages, especially in environmental health and malaria control. A 1990 assessment related that participants' pride, self-confidence, and ability to solve problems regarding the healthy development of their children increased; groups learned to make use of the physical, human, and institutional resources from their environments; and participants' children remained in school and performed better. Conclusions from a decade of loose experimentation suggest that through communication community women can be organized to provide basic early education and early childhood activities can help rural children over the cultural barrier of school.

  7. The Early Development of Kinetic Theory.

    Science.gov (United States)

    Whitaker, Robert D.

    1979-01-01

    A review of the work of Bernoulli and other early contributors to kinetic theory. One significant point is that the most outstanding work in this early period was done by a little-known Scotsman, John J. Waterston. (BB)

  8. Windows of opportunity: tresholds to mangrove seedling establishement on tidal flats

    NARCIS (Netherlands)

    Balke, T.; Bouma, T.J.; Horstman, Erik; Webb, E.L.; Erftemeijer, P.L.A.; Herman, P.M.J.

    2011-01-01

    Physical processes limiting colonization of bare tidal flats by pioneer mangrove species have commonly been described but not yet quantified. Understanding thresholds to early seedling establishment is critical for successful restoration and management of mangrove forests. We determined how seedling

  9. Windows of opportunity: thresholds to mangrove seedling establishment on tidal flats

    NARCIS (Netherlands)

    Balke, T.; Bouma, T.J.; Horstman, E.M.; Webb, E.L.; Erftemeijer, P.L.A.; Herman, P.M.J.

    2011-01-01

    Physical processes limiting colonization of bare tidal flats by pioneer mangrove species have commonly been described but not yet quantified. Understanding thresholds to early seedling establishment is critical for successful restoration and management of mangrove forests. We determined how seedling

  10. Abiotic stress induces change in Cinnamoyl CoA Reductase (CCR) protein abundance and lignin deposition in developing seedlings of Leucaena leucocephala.

    Science.gov (United States)

    Srivastava, Sameer; Vishwakarma, Rishi K; Arafat, Yasir Ali; Gupta, Sushim K; Khan, Bashir M

    2015-04-01

    Aboitic stress such as drought and salinity are class of major threats, which plants undergo through their lifetime. Lignin deposition is one of the responses to such abiotic stresses. The gene encoding Cinnamoyl CoA Reductase (CCR) is a key gene for lignin biosynthesis, which has been shown to be over-expressed under stress conditions. In the present study, developing seedlings of Leucaena leucocephala (Vernacular name: Subabul, White popinac) were treated with 1 % mannitol and 200 mM NaCl to mimic drought and salinity stress conditions, respectively. Enzyme linked immunosorbant assay (ELISA) based expression pattern of CCR protein was monitored coupled with Phlorogucinol/HCl activity staining of lignin in transverse sections of developing L. leucocephala seedlings under stress. Our result suggests a differential lignification pattern in developing root and stem under stress conditions. Increase in lignification was observed in mannitol treated stems and corresponding CCR protein accumulation was also higher than control and salt stress treated samples. On the contrary CCR protein was lower in NaCl treated stems and corresponding lignin deposition was also low. Developing root tissue showed a high level of CCR content and lignin deposition than stem samples under all conditions tested. Overall result suggested that lignin accumulation was not affected much in case of developing root however developing stems were significantly affected under drought and salinity stress condition.

  11. The effects of the phospholipase D-antagonist 1-butanol on seedling development and microtubule organisation in Arabidopsis.

    Science.gov (United States)

    Gardiner, John; Collings, David A; Harper, John D I; Marc, Jan

    2003-07-01

    The organisation of plant microtubules into distinct arrays during the cell cycle requires interactions with partner proteins. Having recently identified a 90-kDa phospholipase D (PLD) that associates with microtubules and the plasma membrane [Gardiner et al. (2001) Plant Cell 13: 2143], we exposed seeds and young seedlings of Arabidopsis to 1-butanol, a specific inhibitor of PLD-dependent production of the signalling molecule phosphatidic acid (PA). When added to agar growth media, 0.2% 1-butanol strongly inhibited the emergence of the radicle and cotyledons, while 0.4% 1-butanol effectively blocked germination. When normal seedlings were transferred onto media containing 0.2% and 0.4% 1-butanol, the inhibitor retarded root growth by about 40% and 90%, respectively, by reducing cell elongation. Inhibited plants showed significant swelling in the root elongation zone, bulbous or branched root hairs, and modified cotyledon morphology. Confocal immunofluorescence microscopy of root tips revealed that 1-butanol disrupted the organisation of interphase cortical microtubules. Butanol isomers that do not inhibit PLD-dependent PA production, 2- and 3-butanol, had no effect on seed germination, seedling growth, or microtubule organisation. We propose that production of PA by PLD may be required for normal microtubule organisation and hence normal growth in Arabidopsis.

  12. Reduction of methylviologen-mediated oxidative stress tolerance in antisense transgenic tobacco seedlings through restricted expression of StAPX.

    Science.gov (United States)

    Sun, Wei-Hong; Wang, Yong; He, Hua-Gang; Li, Xue; Song, Wan; Du, Bin; Meng, Qing-Wei

    2013-07-01

    Ascorbate peroxidases are directly involved in reactive oxygen species (ROS) scavenging by reducing hydrogen peroxide to water. The tomato thylakoid-bound ascorbate peroxidase gene (StAPX) was introduced into tobacco. RNA gel blot analysis confirmed that StAPX in tomato leaves was induced by methylviologen-mediated oxidative stress. The sense transgenic seedlings exhibited higher tAPX activity than that of the wild type (WT) plants under oxidative stress conditions, while the antisense seedlings exhibited lower tAPX activity. Lower APX activities of antisense transgenic seedlings caused higher malondialdehyde contents and relative electrical conductivity. The sense transgenic seedlings with higher tAPX activity maintained higher chlorophyll content and showed the importance of tAPX in maintaining the optimal chloroplast development under methylviologen stress conditions, whereas the antisense lines maintained lower chlorophyll content than WT seedlings. Results indicated that the over-expression of StAPX enhanced tolerance to methylviologen-mediated oxidative stress in sense transgenic tobacco early seedlings, whereas the suppression of StAPX in antisense transgenic seedlings showed high sensitivity to oxidative stress.

  13. Reduction of methylviologen-mediated oxidative stress tolerance in antisense transgenic tobacco seedlings through restricted expression of StAPX

    Institute of Scientific and Technical Information of China (English)

    Wei-hong SUN; Yong WANG; Hua-gang HE; Xue LI; Wan SONG; Bin DU; Qing-wei MENG

    2013-01-01

    Ascorbate peroxidases are directly involved in reactive oxygen species (ROS) scavenging by reducing hydrogen peroxide to water.The tomato thylakoid-bound ascorbate peroxidase gene (StAPX) was introduced into tobacco.RNA gel blot analysis confirmed that StAPX in tomato leaves was induced by methylviologen-mediated oxidative stress.The sense transgenic seedlings exhibited higher tAPX activity than that of the wild type (WT) plants under oxidative stress conditions,while the antisense seedlings exhibited lower tAPX activity.Lower APX activities of antisense transgenic seedlings caused higher malondialdehyde contents and relative electrical conductivity.The sense transgenic seedlings with higher tAPX activity maintained higher chlorophyll content and showed the importance of tAPX in maintaining the optimal chloroplast development under methylviologen stress conditions,whereas the antisense lines maintained lower chlorophyll content than WT seedlings.Results indicated that the over-expression of StAPX enhanced tolerance to methylviologen-mediated oxidative stress in sense transgenic tobacco early seedlings,whereas the suppression of StAPX in antisense transgenic seedlings showed high sensitivity to oxidative stress.

  14. The development of storytelling in early childhood

    Directory of Open Access Journals (Sweden)

    Ljubica Marjanovič Umek

    2011-01-01

    Full Text Available Storytelling is an important aspect of child's language competence, which largely depends on her/his understanding and expression of a decontextualised content and develops rapidly in the period between the second and sixth year of life. The purpose of this study was to examine age differences in children's storytelling in the period between the third and sixth year of age. In addition, we considered the effect of gender on storytelling of children of different ages. The sample included 156 children aged from 3 to 6 years, who were divided into 3 age groups, namely children, aged 3, 4 and 5 years. Child's storytelling competence was assessed with the Little Glove Storytelling Test. Children's stories told by a standard set of illustrations, were analyzed in terms of criteria, designed to assess the developmental level of the stories. The criteria refer to the words, included in the story, the grammatical structure and the content of the story. The obtained results suggested that several important changes in the development of storytelling occur within the period of early childhood. The 5-years-old children told longer stories with a more complex grammatical structure and a coherent content as the 3-years-old children. Children's achievements on the individual criteria for assessing the developmental level of the stories progressed relatively steadily through all three age groups. The results also showed that gender had no significant effect on the storytelling of children of different ages.

  15. Nutrition and brain development in early life.

    Science.gov (United States)

    Prado, Elizabeth L; Dewey, Kathryn G

    2014-04-01

    Presented here is an overview of the pathway from early nutrient deficiency to long-term brain function, cognition, and productivity, focusing on research from low- and middle-income countries. Animal models have demonstrated the importance of adequate nutrition for the neurodevelopmental processes that occur rapidly during pregnancy and infancy, such as neuron proliferation and myelination. However, several factors influence whether nutrient deficiencies during this period cause permanent cognitive deficits in human populations, including the child's interaction with the environment, the timing and degree of nutrient deficiency, and the possibility of recovery. These factors should be taken into account in the design and interpretation of future research. Certain types of nutritional deficiency clearly impair brain development, including severe acute malnutrition, chronic undernutrition, iron deficiency, and iodine deficiency. While strategies such as salt iodization and micronutrient powders have been shown to improve these conditions, direct evidence of their impact on brain development is scarce. Other strategies also require further research, including supplementation with iron and other micronutrients, essential fatty acids, and fortified food supplements during pregnancy and infancy. © 2014 International Life Sciences Institute.

  16. Effect of Perlite Substrates and Irrigating Nutrient Solution on the Growth and Development of Tomato Plug Seedlings and Root Environment%珍珠岩配比基质结合浇灌营养液对番茄穴盘幼苗生长发育和根际环境的影响

    Institute of Scientific and Technical Information of China (English)

    米国全; 程志芳; 赵肖斌; 王晋华

    2012-01-01

    以番茄品种中杂9号(晚熟品种)和中杂109(早熟品种)为试材,研究了珍珠岩+蛭石和草炭+蛭石(体积比均为2∶1)2种基质及其结合浇灌营养液对番茄穴盘幼苗生长发育、根际EC值和pH值的影响.结果表明,与基质草炭+蛭石相比,珍珠岩+蛭石营养条件较差,不利于番茄穴盘幼苗的生长.而珍珠岩+蛭石+营养液(ZZS)条件下培育的中杂109番茄穴盘幼苗壮苗指数(0.044 4)、G值(0.026 6)、花蕾长度(0.94 cm)、叶片叶绿素含量(1.303mg/g),分别高出草炭+蛭石+营养液(CZS)培育的穴盘幼苗33.7%、35.0%、9.3%、2.00,根际EC值(0.45 mS/cm)和pH值(7.10)亦适合番茄幼苗生长.ZZS比CZS更有利于增加中杂9号和中杂109番茄幼苗的株高和茎粗.因此,以珍珠岩+蛭石(2∶1)基质配比结合浇灌营养液更有利于培育番茄穴盘壮苗.%Two tomato varieties,Zhongza 9 and Zhongza 109 with late-maturing and early-maturing, respectively, were used to investigate the influence of two substrates ( perlite + vermiculite, 2 : l;turf+vermiculite, 2 :1 Dand irrigating nutrient solution on sound seedling index, G value, bud length,chlorophyll content and EC, pH under tomato plug technology. The results showed that perlite+vermiculite (ZZB) had a poor nutritional condition and was not helpful to growth and development of the tomato plug seedlings compared to turf-(-vermiculite (CZB). the sound seedling index (0.044 4),G value (0. 026 6),bud length (0. 94 cm), chlorophyll contentd. 303 mg/g) of Zhongza 109 tomato plug seedlings under the perlite+vermiculite and irrigating nutrient solution (ZZS) were respectively 33. 7% ,35. 0% ,9. 3% ,2. 0% higher than those of Zhongza 109 tomato plug seedlings under the turf + vermiculite and irrigating nutrient solution (CZS). The plant height and stem diameter of tomato plug seedlings under perlite + vermiculite and irrigating nutrient solution were higher than those of tomato plug seedlings under turf

  17. Ex Vitro Seedling Development from In Vitro Rhizome-Like Bodies in Eulophia promensis Lindl.: A New Technique for Orchid Propagation

    Directory of Open Access Journals (Sweden)

    Mohammad Musharof Hossain

    2015-01-01

    Full Text Available This communication describes in vitro seed germination, embryo differentiation, and ex vitro seedling production from in vitro rhizome-like bodies of a terrestrial orchid, Eulophia promensis Lindl. Effects of two nutrient media, namely, Murashige and Skoog (MS and Phytotechnology Orchid Seed Sowing medium (P723 supplemented with 6-benzylaminopurine (BAP; 0.5–1.0 mgL−1 and/or α-naphthalene acetic acid (NAA; 0.5–1.0 mgL−1 and activated charcoal (2.0 gL−1, were studied on seed germination and subsequent development of embryos. Maximum seed germination (100% was recorded in P723 medium fortified with 1.0 mgL−1 BAP + 2.0 gL−1 activated charcoal. The different developmental stages of protocorm morphogenesis were traced out. In subsequent subcultures, the protocorms proliferated profusely and developed rhizome-like bodies (RLBs with numerous hair-like structures. These RLBs were transferred to pots containing potting mixture composed of humus + coir dust + saw dust (1 : 1 : 1 where ∼80% of RLBs survived and produced 1–3 seedlings per RLB. This is the first time report for in vitro germination of seeds and ex vitro seedling production from in vitro raised RLBs in Eulophia promensis. This is a time saving and cost effective protocol that could be extended to other economically important, rare, and endangered orchids for propagation and conservation.

  18. Early Parental Depression and Child Language Development

    Science.gov (United States)

    Paulson, James F.; Keefe, Heather A.; Leiferman, Jenn A.

    2009-01-01

    Objective: To examine the effects of early maternal and paternal depression on child expressive language at age 24 months and the role that parent-to-child reading may play in this pathway. Participants and methods: The 9-month and 24-month waves from a national prospective study of children and their families, the Early Childhood Longitudinal…

  19. A stochastic model for early placental development.

    KAUST Repository

    Cotter, Simon L

    2014-08-01

    In the human, placental structure is closely related to placental function and consequent pregnancy outcome. Studies have noted abnormal placental shape in small-for-gestational-age infants which extends to increased lifetime risk of cardiovascular disease. The origins and determinants of placental shape are incompletely understood and are difficult to study in vivo. In this paper, we model the early development of the human placenta, based on the hypothesis that this is driven by a chemoattractant effect emanating from proximal spiral arteries in the decidua. We derive and explore a two-dimensional stochastic model, and investigate the effects of loss of spiral arteries in regions near to the cord insertion on the shape of the placenta. This model demonstrates that disruption of spiral arteries can exert profound effects on placental shape, particularly if this is close to the cord insertion. Thus, placental shape reflects the underlying maternal vascular bed. Abnormal placental shape may reflect an abnormal uterine environment, predisposing to pregnancy complications. Through statistical analysis of model placentas, we are able to characterize the probability that a given placenta grew in a disrupted environment, and even able to distinguish between different disruptions.

  20. Sensitivity of cold acclimation to elevated autumn temperature in field-grown Pinus strobus seedlings

    Directory of Open Access Journals (Sweden)

    Christine Yao-Yun Chang

    2015-03-01

    Full Text Available Climate change will increase autumn air temperature, while photoperiod decrease will remain unaffected. We assessed the effect of increased autumn air temperature on timing and development of cold acclimation and freezing resistance in Eastern white pine (EWP, Pinus strobus under field conditions. For this purpose we simulated projected warmer temperatures for southern Ontario in a Temperature Free-Air-Controlled Enhancement (T-FACE experiment and exposed EWP seedlings to ambient (Control or elevated temperature (ET, +1.5°C/+3°C during day/night. Photosynthetic gas exchange, chlorophyll fluorescence, photoprotective pigments, leaf non-structural carbohydrates (NSC, and cold hardiness were assessed over two consecutive autumns. Nighttime temperature below 10°C and photoperiod below 12h initiated downregulation of assimilation in both treatments. When temperature further decreased to 0°C and photoperiod became shorter than 10h, downregulation of the light reactions and upregulation of photoprotective mechanisms occurred in both treatments. While ET seedlings did not delay the timing of the downregulation of assimilation, stomatal conductance in ET seedlings was decreased by 20-30% between August and early October. In both treatments leaf NSC composition changed considerably during autumn but differences between Control and ET seedlings were not significant. Similarly, development of freezing resistance was induced by exposure to low temperature during autumn, but the timing was not delayed in ET seedlings compared to Control seedlings. Our results indicate that EWP is most sensitive to temperature changes during October and November when downregulation of photosynthesis , enhancement of photoprotection, synthesis of cold-associated NSCs and development of freezing resistance occur. However, we also conclude that the timing of the development of freezing resistance in EWP seedlings is not affected by moderate temperature increases used in our

  1. Interaction of SiO2 Nanoparticles with Seed Prechilling on Germination and Early Seedling Growth of Tall Wheatgrass (Agropyron Elongatum L.

    Directory of Open Access Journals (Sweden)

    Azimi Reyhane

    2014-09-01

    Full Text Available The effect of six SiO2 nanosized concentrations (0, 5, 20, 40, 60 and 80 mg L-1 and three seed prechilling treatments (control, seed prechilling before nano SiO2 treatments, treatments of seed with nano SiO2 before prechilling on germination and seedling growth of tall wheatgrass (Agropyron elongatum L. were studied. Results indicated that application of SiO2 nanoparticles significantly increased seed germination of tall wheatgrass from 58 percent in control group to 86.3 and 85.7 percent in 40 and 60 mg L-1, respectively. Applying SiO2 nanoparticles increased dry weight of shoot, root and seedling of tall wheatgrass. Increasing concentration of nanoparticle from 0 up to 40 mg L-1 increased seedling weight around 49 percent compared to the control, nevertheless decreased under 60 and 80 mg L-1 treatments. In conclusion, seed prechilling in combination with SiO2 nanoparticles largely broke the seed dormancy for A. elongatum.

  2. Starch bioengineering affects cereal grain germination and seedling establishment

    DEFF Research Database (Denmark)

    Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel;

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...... structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics...... showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated...

  3. Two novel techniques to screen Abies seedlings for resistance to the balsam woolly adelgid, Adelges piceae.

    Science.gov (United States)

    Newton, Leslie; Frampton, John; Monahan, John; Goldfarb, Barry; Hain, Fred

    2011-01-01

    Since its introduction into the Southern Appalachians in the 1950s, the balsam woolly adelgid, Adelges piceae Ratzeburg (Hemiptera: Adelgidae), has devastated native populations of Fraser fir, Abies fraseri (Pursh) Poir. (Pinales: Pinaceae), and has become a major pest in Christmas tree plantations requiring expensive chemical treatments. Adelges piceae-resistant Fraser fir trees would lessen costs for the Christmas tree industry and assist in the restoration of native stands. Resistance screening is an important step in this process. Here, four studies directed toward the development of time- and cost-efficient techniques for screening are reported. In the first study, three methods to artificially infest seedlings of different ages were evaluated in a shade-covered greenhouse. Two-year-old seedlings had much lower infestation levels than 7 year-old seedlings. Placing infested bark at the base of the seedling was less effective than tying infested bark to the seedling or suspending infested bolts above the seedling. Although the two latter techniques resulted in similar densities on the seedlings, they each have positive and negative considerations. Attaching bark to uninfested trees is effective, but very time consuming. The suspended bolt method mimics natural infestation and is more economical than attaching bark, but care must be taken to ensure an even distribution of crawlers falling onto the seedlings. The second study focused on the density and distribution of crawlers falling from suspended bolts onto paper gridded into 7.6 × 7.6 cm cells. Crawler density in a 30 cm band under and to each side of the suspended bolt ranged from 400 to over 3000 crawlers per cell (1 to 55 crawlers per cm²). In the third study, excised branches from 4 year-old A. fraseri and A. vetchii seedlings were artificially infested with A. piceae to determine whether this technique may be useful for early resistance screening. The excised A. fraseri branches supported complete

  4. Development of a Direct Headspace Collection Method from Arabidopsis Seedlings Using HS-SPME-GC-TOF-MS Analysis

    Directory of Open Access Journals (Sweden)

    Kazuki Saito

    2013-04-01

    Full Text Available Plants produce various volatile organic compounds (VOCs, which are thought to be a crucial factor in their interactions with harmful insects, plants and animals. Composition of VOCs may differ when plants are grown under different nutrient conditions, i.e., macronutrient-deficient conditions. However, in plants, relationships between macronutrient assimilation and VOC composition remain unclear. In order to identify the kinds of VOCs that can be emitted when plants are grown under various environmental conditions, we established a conventional method for VOC profiling in Arabidopsis thaliana (Arabidopsis involving headspace-solid-phase microextraction-gas chromatography-time-of-flight-mass spectrometry (HS-SPME-GC-TOF-MS. We grew Arabidopsis seedlings in an HS vial to directly perform HS analysis. To maximize the analytical performance of VOCs, we optimized the extraction method and the analytical conditions of HP-SPME-GC-TOF-MS. Using the optimized method, we conducted VOC profiling of Arabidopsis seedlings, which were grown under two different nutrition conditions, nutrition-rich and nutrition-deficient conditions. The VOC profiles clearly showed a distinct pattern with respect to each condition. This study suggests that HS-SPME-GC-TOF-MS analysis has immense potential to detect changes in the levels of VOCs in not only Arabidopsis, but other plants grown under various environmental conditions.

  5. Classroom Effects of an Early Childhood Educator Professional Development Partnership

    Science.gov (United States)

    Algozzine, Bob; Babb, Julie; Algozzine, Kate; Mraz, Maryann; Kissel, Brian; Spano, Sedra; Foxworth, Kimberly

    2011-01-01

    We evaluated an Early Childhood Educator Professional Development (ECEPD) project that provided high-quality, sustained, and intensive professional development designed to support developmentally appropriate instruction for preschool-age children based on the best available research on early childhood pedagogy, child development, and preschool…

  6. Parents' Role in the Early Head Start Children's Language Development

    Science.gov (United States)

    Griswold, Cecelia Smalls

    2014-01-01

    The development of language during a child's early years has been linked to parental involvement. While Early Head Start (EHS) researchers have theorized that parental involvement is an important factor in language development, there has been little research on how parents view their roles in the language development process. The purpose of this…

  7. Classroom Effects of an Early Childhood Educator Professional Development Partnership

    Science.gov (United States)

    Algozzine, Bob; Babb, Julie; Algozzine, Kate; Mraz, Maryann; Kissel, Brian; Spano, Sedra; Foxworth, Kimberly

    2011-01-01

    We evaluated an Early Childhood Educator Professional Development (ECEPD) project that provided high-quality, sustained, and intensive professional development designed to support developmentally appropriate instruction for preschool-age children based on the best available research on early childhood pedagogy, child development, and preschool…

  8. Potential effects of arboreal and terrestrial avian dispersers on seed dormancy, seed germination and seedling establishment in Ormosia (Papilionoideae) species in Peru

    Science.gov (United States)

    Foster, Mercedes S.

    2008-01-01

    The relative effectiveness of arboreal or terrestrial birds at dispersing seeds of Ormosia macrocalyx and O. bopiensis (Fabaceae: Papilionoideae) were studied in south-eastern Peru. Seeds of both species were either scarified, to represent seed condition after dispersal by terrestrial birds, or left intact, to represent seed condition after dispersal by arboreal birds. Seeds were distributed along forest transects, and germination, seedling development and mortality were monitored to determine the successes of the two groups at producing seedlings. Scarified seeds germinated with the early rains of the dry-to-wet-season transition, when erratic rainfall was interspersed with long dry spells. Intact seeds germinated 30 d later when the rain was more plentiful and regular. Intact seeds of O. macrocalyx gave rise to significantly more seedlings (41.1% vs. 25.5%) than did scarified seeds, in part, because significantly more seedlings from scarified seeds (n = 20) than from intact seeds (n = 3) died from desiccation when their radicles failed to enter the dry ground present during the dry-to-wet-season transition. Also, seedlings from scarified seeds were neither larger nor more robust than those from intact seeds despite their longer growing period. Results are consistent with the hypothesis that dispersal effectiveness of arboreal birds, at least for O. macrocalyx, is greater than that of terrestrial birds. Screen-house experiments in which seedlings developed under different watering regimes supported this result. Numbers of seedlings developing from intact and scarified seeds of O. bopiensis did not differ significantly.

  9. A membrane microdomain-associated protein, Arabidopsis Flot1, is involved in a clathrin-independent endocytic pathway and is required for seedling development.

    Science.gov (United States)

    Li, Ruili; Liu, Peng; Wan, Yinglang; Chen, Tong; Wang, Qinli; Mettbach, Ursula; Baluska, Frantisek; Samaj, Jozef; Fang, Xiaohong; Lucas, William J; Lin, Jinxing

    2012-05-01

    Endocytosis is essential for the maintenance of protein and lipid compositions in the plasma membrane and for the acquisition of materials from the extracellular space. Clathrin-dependent and -independent endocytic processes are well established in yeast and animals; however, endocytic pathways involved in cargo internalization and intracellular trafficking remain to be fully elucidated for plants. Here, we used transgenic green fluorescent protein-flotillin1 (GFP-Flot1) Arabidopsis thaliana plants in combination with confocal microscopy analysis and transmission electron microscopy immunogold labeling to study the spatial and dynamic aspects of GFP-Flot1-positive vesicle formation. Vesicle size, as outlined by the gold particles, was ∼100 nm, which is larger than the 30-nm size of clathrin-coated vesicles. GFP-Flot1 also did not colocalize with clathrin light chain-mOrange. Variable-angle total internal reflection fluorescence microscopy also revealed that the dynamic behavior of GFP-Flot1-positive puncta was different from that of clathrin light chain-mOrange puncta. Furthermore, disruption of membrane microdomains caused a significant alteration in the dynamics of Flot1-positive puncta. Analysis of artificial microRNA Flot1 transgenic Arabidopsis lines established that a reduction in Flot1 transcript levels gave rise to a reduction in shoot and root meristem size plus retardation in seedling growth. Taken together, these findings support the hypothesis that, in plant cells, Flot1 is involved in a clathrin-independent endocytic pathway and functions in seedling development.

  10. Efeito de diferentes substratos sobre o desenvolvimento de mudas de Acacia sp. Effect of different substrates on the development of Acacia sp. seedlings

    Directory of Open Access Journals (Sweden)

    Alexson de Mello Cunha

    2006-04-01

    Full Text Available Os biossólidos têm sido estudados como fonte de matéria orgânica na agricultura. Objetivou-se avaliar o desenvolvimento de mudas de Acacia mangium e Acacia auriculiformis em diferentes substratos: a horizonte Bw com areia lavada (1:1, v:v e adubação mineral de 160, 640 e 160 g m-3de N, P2O5 e K2O, respectivamente (HB; b horizonte Bw com areia lavada e esterco bovino (1:1:1, v:v (HBE; c horizonte Bw com areia lavada e lodo de esgoto (1:1:1, v:v (HBL; e d 100% de lodo de esgoto (LE. Aplicou-se 1 kg de CaCO3 p.a. por m³ de substrato. Foram utilizadas sementes inoculadas com rizóbio e não-inoculadas, determinando-se, aos 90 dias após a semeadura, a altura das plantas, o diâmetro do colo e o peso da matéria seca da raiz e da parte aérea, na qual se determinaram N, P, K, Ca e Mg. O delineamento estatístico foi inteiramente casualizado, no esquema fatorial 2 x 4 (com ou sem inoculação x 4 substratos. No LE com inoculação, obteve-se melhor crescimento das mudas. O HBE produziu efeito superior no desenvolvimento das mudas em relação àquele com a mesma proporção de material orgânico na forma de lodo (HBL. Na maioria dos parâmetros avaliados não houve diferença devido à inoculação dos substratos HBE, HBL e HB, provavelmente devido à existência de bactérias nativas nesses substratos. As mudas desenvolvidas no substrato LE foram as que acumularam mais N e Ca, principalmente quando inoculadas. Houve tendência de maior acúmulo de P, K e Mg na parte aérea das mudas desenvolvidas no substrato HBE.Sewage sludge has been studied as source of organic matter on seedling production. Thus, this study aimed to evaluate the development of Acacia mangium and Acacia auriculiformis seedlings in the following substrates: a oxic horizon + sand (1:1, v:v + 160, 640 e 160 g m-3 of N, P2O5 and K2O respectively (HB; b oxic horizon + sand + cattle manure (1:1:1, v:v (HBE; c oxic horizon + sand + sewage sludge (1:1:1, v:v (HBL and; d 100% sewage

  11. Desenvolvimento de mudas de Aroeira (Schinus terebinthifolius e sombreiro (Clitoria fairchildiana sob condições de sombreamento Development of Schinus terebinthifolius and Clitoria fairchildiana seedlings under shading

    Directory of Open Access Journals (Sweden)

    Silvana de Paula Quintão Scalon

    2006-02-01

    Full Text Available Objetivou-se com este trabalho avaliar o desenvolvimento das mudas de Schinus terebinthifolius e Clitoria fairchildiana sob condiç��es de sombreamento e pleno sol. As mudas foram cultivadas sob sombrites de 70% e 50% de luz e sob luz plena. O experimento foi conduzido em DBC com 4 repetições de 20 mudas. Foram avaliados a altura do caule e o diâmetro do colo a cada vinte e um dias. Ao final do experimento foram realizadas as avaliações de peso seco total (PST-g, área foliar (AF-dm², razão de peso foliar (RPF -g/g; e peso específico de folha (PEF -g/ dm². As sementes de aroeira do campo e do sombreiro apresentaram 70% e 85% de germinação, respectivamente. S.terebinthifolius tolera bem um sombreamento moderado (70% de luz, sendo seu cultivo a pleno sol o mais indicado, pois é quando as mudas atingem menor altura (32,93 cm, diâmetro médio de 7,15 mm, maior PST (74,66 g; menor PEF (0,025; as mudas de C.fairchildiana sob condições de pleno sol não se desenvolveram satisfatoriamente, embora a altura não tenha variado entre os níveis de luz (16,39 cm, apresentaram menor diâmetro (5,32 mm, menor PST (26,22 g, menor AF (32,98 dm² e maior PEF (0,4.The objective of this work was to evaluate the development of S. terebinthifolius and C. fairchildiana seedlings under shade and full sunlight conditions. The seedlings were cultivated under 70% and 50% sunlight and full sunlight. The experiment was carried out in a randomized block design with four replications of twenty seedlings. Stem height and collar diameter were evaluated every 21 days. At the end of the experiment total dried weight (TDW-g, leaf area (LA-dm², leaf weight rate LWR-g/g and leaf specific weight (LSW-g/dm² were also evaluated. The seeds of S.terebinthifolius and C. fairchildiana showed a germination of 70% and 85% respectively. S. terebinthifolius tolerated moderate shade (70% sunligth however, full sunlight seemed to be most appropriate. C. fairchildiana

  12. The Study of Seedlings

    NARCIS (Netherlands)

    Jacobs, M.

    1966-01-01

    ”The seedling represents the most critical stage in the life of a tree. Conditions of seeding and germination may be entirely favourable, and natural seedlings may appear in countless quantities at the beginning of the rainy season, only to disappear largely or entirely within a comparatively short

  13. EMF radiations (1800 MHz)-inhibited early seedling growth of maize (Zea mays) involves alterations in starch and sucrose metabolism.

    Science.gov (United States)

    Kumar, Arvind; Singh, Harminder Pal; Batish, Daizy R; Kaur, Shalinder; Kohli, Ravinder Kumar

    2016-07-01

    The present study investigated the impact of 1800-MHz electromagnetic field radiations (EMF-r), widely used in mobile communication, on the growth and activity of starch-, sucrose-, and phosphate-hydrolyzing enzymes in Zea mays seedlings. We exposed Z. mays to modulated continuous wave homogenous EMF-r at specific absorption rate (SAR) of 1.69±0.0 × 10(-1) W kg(-1) for ½, 1, 2, and 4 h. The analysis of seedlings after 7 days revealed that short-term exposure did not induce any significant change, while longer exposure of 4 h caused significant growth and biochemical alterations. There was a reduction in the root and coleoptile length with more pronounced effect on coleoptile growth (23 % reduction on 4-h exposure). The contents of photosynthetic pigments and total carbohydrates declined by 13 and 18 %, respectively, in 4-h exposure treatments compared to unexposed control. The activity of starch-hydrolyzing enzymes-α- and β-amylases-increased by ∼92 and 94 %, respectively, at an exposure duration of 4 h, over that in the control. In response to 4-h exposure treatment, the activity of sucrolytic enzymes-acid invertases and alkaline invertases-was increased by 88 and 266 %, whereas the specific activities of phosphohydrolytic enzymes (acid phosphatases and alkaline phosphatases) showed initial increase up to ≤2 h duration and then declined at >2 h exposure duration. The study concludes that EMF-r-inhibited seedling growth of Z. mays involves interference with starch and sucrose metabolism.

  14. Dual Language Exposure and Early Bilingual Development

    Science.gov (United States)

    Hoff, Erifka; Core, Cynthia; Place, Silvia; Rumiche, Rosario; Senor, Melissa; Parra, Marisol

    2012-01-01

    The extant literature includes conflicting assertions regarding the influence of bilingualism on the rate of language development. The present study compared the language development of equivalently high-SES samples of bilingually and monolingually developing children from 1 ; 10 to 2 ; 6. The monolingually developing children were significantly…

  15. Desenvolvimento vegetativo inicial de porta-enxertos cítricos cultivados em diferentes substratos Vegetative development of citrus rootstocks seedlings cultivated in different growing media

    Directory of Open Access Journals (Sweden)

    Gilmar Schäfer

    2006-12-01

    Full Text Available Com o objetivo de avaliar o desenvolvimento vegetativo de porta-enxertos cítricos em diferentes substratos de cultivo, foi instalado um experimento, conduzido em casa de vegetação, com sistema de irrigação por microaspersão, na Estação Experimental Agronômica da UFRGS, a partir do dia 27 de setembro de 2001. O delineamento experimental adotado foi em blocos ao acaso, em esquema de parcela subdividida, com quatro repetições. Nas parcelas principais, foram testados substratos, sendo dois encontrados no comércio especializado em horticultura (Comercial 1 e 2 e uma mistura (turfa mais casca de arroz carbonizada - na proporção de 1:1 em v:v. Nas subparcelas, foram testados quatro porta-enxertos cítricos ("Trifoliata", Citrange "C13", Citrange "C37" e Limoeiro "Cravo". Os principais resultados demonstram que é possível produzir porta-enxertos, na fase de sementeira, com bom tamanho e desenvolvimento radicular, com 120 dias após a semeadura, e que as características químicas dos substratos são determinantes para o desenvolvimento adequado dos porta-enxertos, sendo prejudicial a salinidade elevada.The present study was aimed at evaluating the vegetative development of citrus seedlings rootstocks cultivated in different substrates. The experiment was installed at greenhouse conditions in the Estação Experimental Agronômica UFRGS, from September 27, 2001. The experimental design used was that of randomized blocks, in a split plot scheme, with four replications. In the main parcels were tested substrate, two commercial, found in the specialized trade in horticulture and a mixture. In the sub parcels were tested four citrus rootstock (Trifoliate orange, 'C13' Citrange, 'C37' Citrange and 'Rangpur' Lime. The main results showing that is possible to produce citrus rootstock seedlings with good size and root development, with 120 days after sowing. The chemistries characteristics of the substrate are decisive for the appropriate

  16. Dual language exposure and early bilingual development.

    Science.gov (United States)

    Hoff, Erika; Core, Cynthia; Place, Silvia; Rumiche, Rosario; Señor, Melissa; Parra, Marisol

    2012-01-01

    The extant literature includes conflicting assertions regarding the influence of bilingualism on the rate of language development. The present study compared the language development of equivalently high-SES samples of bilingually and monolingually developing children from 1 ; 10 to 2 ; 6. The monolingually developing children were significantly more advanced than the bilingually developing children on measures of both vocabulary and grammar in single language comparisons, but they were comparable on a measure of total vocabulary. Within the bilingually developing sample, all measures of vocabulary and grammar were related to the relative amount of input in that language. Implications for theories of language acquisition and for understanding bilingual development are discussed.

  17. Assessing Home Environment for Early Child Development in Pakistan

    Science.gov (United States)

    Nadeem, Sanober; Rafique, Ghazala; Khowaja, Liaquat; Yameen, Anjum

    2014-01-01

    Family environment plays a very important role in early child development and the availability of stimulating material in the early years of a child's life is crucial for optimising development. The Home Observation for Measurement of the Environment (HOME) inventory is one of the most widely used measures to assess the quality and quantity of…

  18. Promoting Professional Development for Physical Therapists in Early Intervention

    Science.gov (United States)

    Catalino, Tricia; Chiarello, Lisa A.; Long, Toby; Weaver, Priscilla

    2015-01-01

    Early intervention service providers are expected to form cohesive teams to build the capacity of a family to promote their child's development. Given the differences in personnel preparation across disciplines of service providers, the Early Childhood Personnel Center is creating integrated and comprehensive professional development models for…

  19. Assessing Home Environment for Early Child Development in Pakistan

    Science.gov (United States)

    Nadeem, Sanober; Rafique, Ghazala; Khowaja, Liaquat; Yameen, Anjum

    2014-01-01

    Family environment plays a very important role in early child development and the availability of stimulating material in the early years of a child's life is crucial for optimising development. The Home Observation for Measurement of the Environment (HOME) inventory is one of the most widely used measures to assess the quality and quantity of…

  20. Intraspecific differences in effects of co-contamination of cadmium and arsenate on early seedling growth and metal uptake by wheat

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p < 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.

  1. Development of Entrepreneurship Learning Model for Early Childhood

    Directory of Open Access Journals (Sweden)

    Martha Christianti

    2015-08-01

    Full Text Available This study is an early pace in the research development of entrepreneurship learning model for early childhood. This study aims to explore how learning entrepreneurship that has been done in the early childhood; to know whether parents, teachers, and principals support the entrepreneurship learning; and what kind of values of entrepreneurship can be developed for early childhood. The results of this research are useful to create early childhood entrepreneurial learning design. The research conducts in the form of interviews, observation, and documentation. The result shows that the school which has been developing entrepreneurship has no clear guidance of learning to develop the spirit of entrepreneurship; all teachers and principals in the research agree that entrepreneurship learning developed from an early age. However, there are 90.79% of parents agreed that from an early age has begun to develop the spirit of entrepreneurship and 9.21% said they did not agree; and the values of entrepreneurship that are able to be developed since they are in early age are self-confidence, honesty, independence, responsibility, creative, never give up/hard work, caring for the environment, teamwork, discipline, and respect.

  2. Morphoanatomy of Serjania communis Cambess. seedling (Sapindaceae

    Directory of Open Access Journals (Sweden)

    Willian Adriano Lira Lopes

    2015-07-01

    Full Text Available Serjania communis Cambess. (Sapindaceae is a plant with climbing habit and occurs relatively often in Paraná State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringá, Paraná State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in length and brown color. Seedlings are epigeal phanerocotylar. The seedlings have a hairy hypocotyl, foliaceous cotyledons, reduced epicotyl, and two opposite eophylls. The root is diarch, the hypocotyl shows root-stem transition structure, stem epicotyl, and dorsiventral and hypostomatous cotyledons and eophylls. 'Tirodendros' with 45 days of age do not develop cambial variant.

  3. The upregulation of thiamine (vitamin B1 biosynthesis in Arabidopsis thaliana seedlings under salt and osmotic stress conditions is mediated by abscisic acid at the early stages of this stress response

    Directory of Open Access Journals (Sweden)

    Rapala-Kozik Maria

    2012-01-01

    Full Text Available Abstract Background Recent reports suggest that vitamin B1 (thiamine participates in the processes underlying plant adaptations to certain types of abiotic and biotic stress, mainly oxidative stress. Most of the genes coding for enzymes involved in thiamine biosynthesis in Arabidopsis thaliana have been identified. In our present study, we examined the expression of thiamine biosynthetic genes, of genes encoding thiamine diphosphate-dependent enzymes and the levels of thiamine compounds during the early (sensing and late (adaptation responses of Arabidopsis seedlings to oxidative, salinity and osmotic stress. The possible roles of plant hormones in the regulation of the thiamine contribution to stress responses were also explored. Results The expression of Arabidopsis genes involved in the thiamine diphosphate biosynthesis pathway, including that of THI1, THIC, TH1 and TPK, was analyzed for 48 h in seedlings subjected to NaCl or sorbitol treatment. These genes were found to be predominantly up-regulated in the early phase (2-6 h of the stress response. The changes in these gene transcript levels were further found to correlate with increases in thiamine and its diphosphate ester content in seedlings, as well as with the enhancement of gene expression for enzymes which require thiamine diphosphate as a cofactor, mainly α-ketoglutarate dehydrogenase, pyruvate dehydrogenase and transketolase. In the case of the phytohormones including the salicylic, jasmonic and abscisic acids which are known to be involved in plant stress responses, only abscisic acid was found to significantly influence the expression of thiamine biosynthetic genes, the thiamine diphosphate levels, as well as the expression of genes coding for main thiamine diphosphate-dependent enzymes. Using Arabidopsis mutant plants defective in abscisic acid production, we demonstrate that this phytohormone is important in the regulation of THI1 and THIC gene expression during salt stress

  4. Desenvolvimento de plântulas de limoeiro 'cravo' relacionado a posição de semeadura Development of rangpur lime seedlings in relation to sowing position

    Directory of Open Access Journals (Sweden)

    Walter Geremias Rodriguez Robles

    2000-06-01

    Full Text Available Instalou-se um ensaio em casa de vegetação com o objetivo de relacionar a posição da semente e o desenvolvimento de plântulas de limoeiro `Cravo'. Foram semeadas nas três prováveis posições que a semente tomaria ao ser lançada ao solo ou substrato: 1 deitada; 2 ápice para cima e 3 ápice para baixo. Este experimento foi realizado em bandejas de poliestireno expandido com 128 células, utilizando-se como substrato a mistura de vermiculita expandida e material orgânico vegetal. Adotou-se o delineamento experimental em blocos ao acaso, com 4 repetições e 40 sementes por parcela (1 semente/célula. Aos 75 dias após à semeadura, observou-se maior quantidade de plântulas com raízes normais quando colocadas as sementes nas posições deitada e ápice para baixo. A posição ápice para cima apresentou maior quantidade de plântulas com raízes tortas e enoveladas. O comprimento do sistema radicular foi aproximadamente o dobro da parte aérea, independente da posição da semente, ocorrendo o inverso em relação à massa da matéria seca.This experiment was conducted in a green house, with the objective of relating the position of Rangpur Lime seed to the development of seedlings. Seeds were sown in the three probable positions that they would take when planted in the soil or substratum: 1 sideways; 2 apex upwards and 3 apex downwards. The experiment was performed in plastic trays of expanded poliestirene speedlings with 128 cells filled with the substratum mixture of expanded vermiculite and vegetable organic material. The adopted experimental design used randomized blocks, with 4 replicates and 40 seeds per plot (1 seed/cell. At 75 days of sowing, a larger amount of seedlings with normal roots was observed when seeds are placed are on the side and apex down positions. The position apex upwards presented larger amount of seedlings with crooked and reeled roots. The length of the root system was almost the double of the aerial part

  5. The effects of free amino acids profiles on seeds germination/dormancy and seedlings development of two genetically different cultivars of Yemeni Pomegranates

    Directory of Open Access Journals (Sweden)

    Alhadi Fatima A.

    2012-04-01

    seeds germination in plant, therefore Khazemi germination capacity was assumed to be regulated more or less by these AAs. In addition, changes in amino acid composition in the germinated Khazemi cultivar during various stages of seeds germination including imbibition, germination, and sprouts stages have been noticed to change in response with germination demands. This suggests that amino acids reserves in dry seeds are major determinant for germination capacity and germination behavior in the following steps of germination. The noticed particular AAs increase/decrease along the time course of Khazemi pomegranate germination till establishment of heterotrophic seedlings were used as cornerstones for elucidation and deduction of putative function and relevant biochemical pathways controlling initiation of seeds germination and seedlings developments. Based on publicly available databases of model plants and literatures surveys, we established correlations between prevailing AAs factors as biochemical parameters actively involved in seeds dormancy-breaking and germination process.

  6. School Building in Early Development. Part 1.

    Science.gov (United States)

    Dijkgraaf, C.; Giertz, L. M.

    1975-01-01

    This bulletin, concerned mainly with the educational problems in developing lands, focuses on school development, the future of education, and the schools that will have to be built to meet the needs of the future. The report deals with problems arising from the present rates of dropout in traditional primary education, and proposes possible…

  7. The Early Development of Pharmacology in America.

    Science.gov (United States)

    Parascandola, John

    Presented is a review of the development of the science of pharmacology, the study of the interaction of chemical agents with living matter. The origins of the field are traced from 17th century Europe to the present, with major emphasis upon the scientists and developments made in the field in the United States. (SL)

  8. Early gonad development in zebrafish (Danio rerio)

    African Journals Online (AJOL)

    SAM

    2014-08-13

    Aug 13, 2014 ... months. Many aspects of zebrafish development have been described in the ... development of the nervous system (Kimmel et al., 1994), and aspects of cell ..... to juvenile life stages in the zebrafish (Brown, 1997). Day. 19, therefore .... found throughout the reproductive cycle in fish, but has only been clearly ...

  9. Early development of fern gametophytes in microgravity

    Science.gov (United States)

    Roux, Stanley J.; Chatterjee, Ani; Hillier, Sheila; Cannon, Tom

    2003-01-01

    Dormant spores of the fern Ceratopteris richardii were flown on Shuttle mission STS-93 to evaluate the effects of micro-g on their development and on their pattern of gene expression. Prior to flight the spores were sterilized and sown into one of two environments: (1) Microscope slides in a video-microscopy module; and (2) Petri dishes. All spores were then stored in darkness until use. Spore germination was initiated on orbit after exposure to light. For the spores on microscope slides, cell level changes were recorded through the clear spore coat of the spores by video microscopy. After their exposure to light, spores in petri dishes were frozen in orbit at four different time points during which on earth gravity fixes the polarity of their development. Spores were then stored frozen in Biological Research in Canister units until recovery on earth. The RNAs from these cells and from 1-g control cells were extracted and analyzed on earth after flight to assay changes in gene expression. Video microscopy results revealed that the germinated spores developed normally in microgravity, although the polarity of their development, which is guided by gravity on earth, was random in space. Differential Display-PCR analyses of RNA extracted from space-flown cells showed that there was about a 5% change in the pattern of gene expression between cells developing in micro-g compared to those developing on earth. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.

  10. Early development of fern gametophytes in microgravity

    Science.gov (United States)

    Roux, Stanley J.; Chatterjee, Ani; Hillier, Sheila; Cannon, Tom

    Dormant spores of the fern Ceratopteris richardii were flown on Shuttle mission STS-93 to evaluate the effects of /micro-g on their development and on their pattern of gene expression. Prior to flight the spores were sterilized and sown into one of two environments: (1) Microscope slides in a video-microscopy module; and (2) Petri dishes. All spores were then stored in darkness until use. Spore germination was initiated on orbit after exposure to light. For the spores on microscope slides, cell level changes were recorded through the clear spore coat of the spores by video microscopy. After their exposure to light, spores in petri dishes were frozen in orbit at four different time points during which on earth gravity fixes the polarity of their development. Spores were then stored frozen in Biological Research in Canister units until recovery on earth. The RNAs from these cells and from /1-g control cells were extracted and analyzed on earth after flight to assay changes in gene expression. Video microscopy results revealed that the germinated spores developed normally in microgravity, although the polarity of their development, which is guided by gravity on earth, was random in space. Differential Display-PCR analyses of RNA extracted from space-flown cells showed that there was about a 5% change in the pattern of gene expression between cells developing in /micro-g compared to those developing on earth.

  11. Early Speech Motor Development: Cognitive and Linguistic Considerations

    Science.gov (United States)

    Nip, Ignatius S. B.; Green, Jordan R.; Marx, David B.

    2009-01-01

    This longitudinal investigation examines developmental changes in orofacial movements occurring during the early stages of communication development. The goals were to identify developmental trends in early speech motor performance and to determine how these trends differ across orofacial behaviors thought to vary in cognitive and linguistic…

  12. Medical students' professional identity development in an early nursing attachment.

    NARCIS (Netherlands)

    Helmich, E.; Derksen, E.; Prevoo, M.; Laan, R.F.J.M.; Bolhuis, S.; Koopmans, R.T.C.M.

    2010-01-01

    OBJECTIVES: The importance of early clinical experience for medical training is well documented. However, to our knowledge there are no studies that assess the influence of very early nursing attachments on the professional development and identity construction of medical students. Working as an ass

  13. Early psychosis workforce development: Core competencies for mental health professionals working in the early psychosis field.

    Science.gov (United States)

    Osman, Helen; Jorm, Anthony F; Killackey, Eoin; Francey, Shona; Mulcahy, Dianne

    2017-08-09

    The aim of this study was to identify the core competencies required of mental health professionals working in the early psychosis field, which could function as an evidence-based tool to support the early psychosis workforce and in turn assist early psychosis service implementation and strengthen early psychosis model fidelity. The Delphi method was used to establish expert consensus on the core competencies. In the first stage, a systematic literature search was conducted to generate competency items. In the second stage, a panel consisting of expert early psychosis clinicians from around the world was formed. Panel members then rated each of the competency items on how essential they are to the clinical practice of all early psychosis clinicians. In total, 1023 pieces of literature including textbooks, journal articles and grey literature were reviewed. A final 542 competency items were identified for inclusion in the questionnaire. A total of 63 early psychosis experts participated in 3 rating rounds. Of the 542 competency items, 242 were endorsed as the required core competencies. There were 29 competency items that were endorsed by 62 or more experts, and these may be considered the foundational competencies for early psychosis practice. The study generated a set of core competencies that provide a common language for early psychosis clinicians across professional disciplines and country of practice, and potentially are a useful professional resource to support early psychosis workforce development and service reform. © 2017 John Wiley & Sons Australia, Ltd.

  14. School Building in Early Development. Part 2.

    Science.gov (United States)

    Dijkgraaf, C.; Giertz, L. M.

    1975-01-01

    Development is characterized by urbanization. New settlements grow either as enlargements of existing ones or as new population concentrations. Three periods may be distinguished in the growth of a settlement: (1) the wild period of first settling, (2) the consolidation period, and (3) the stabilized society. The number of school-aged children per…

  15. Pharmacometrics in early clinical drug development

    NARCIS (Netherlands)

    Keizer, R.J.

    2010-01-01

    Pharmacometrics, the science of quantitative clinical pharmacology, has been recognized as one of the main research fields able to improve efficiency in drug development, and to reduce attrition rates on the route from drug discovery to approval. This field of drug research, which builds heavily on

  16. Early Imagining and the Development of Empathy.

    Science.gov (United States)

    Sutherland, Margaret B.

    1985-01-01

    Considers possible links between development of empathy and some children's spontaneous creation of imaginary companions or situations, citing examples of Agatha Christie's "Autobiography." Questions if such activities show ability to "decenter emotionally." Suggests need for better methods of assessing emotional decentering…

  17. Pharmacometrics in early clinical drug development

    NARCIS (Netherlands)

    Keizer, R.J.

    2010-01-01

    Pharmacometrics, the science of quantitative clinical pharmacology, has been recognized as one of the main research fields able to improve efficiency in drug development, and to reduce attrition rates on the route from drug discovery to approval. This field of drug research, which builds heavily on

  18. Developing an Engineering Identity in Early Childhood

    Science.gov (United States)

    Pantoya, Michelle L.; Aguirre-Munoz, Zenaida; Hunt, Emily M.

    2015-01-01

    This project describes a strategy to introduce young children to engineering in a way that develops their engineering identity. The targeted age group is 3-7 year old students because they rarely experience purposeful engineering instruction. The curriculum was designed around an engineering storybook and included interactive academic discussions…

  19. Efeito de reguladores vegetais no desenvolvimento de mudas de Passiflora alata Curtis Effect of plant regulators on Passiflora alata seedlings development

    Directory of Open Access Journals (Sweden)

    Anísio de Oliveira

    2005-04-01

    Full Text Available O principal fator limitante à produção de mudas enxertadas de maracujazeiro é o elevado tempo para a sua formação. Assim, objetivou-se avaliar o efeito de reguladores vegetais no desenvolvimento de mudas de Passiflora alata Curtis, a serem empregadas como porta-enxerto, visando a reduzir o tempo para atingir o ponto de enxertia. O delineamento experimental empregado foi o inteiramente casualisado, em esquema fatorial 4x5 (4 reguladores vegetais x 5 concentrações, com 4 repetições de 25 plantas por parcela. Os tratamentos foram constituídos por 0,0 mg L-1 (testemunha; 25 mg L-1; 50 mg L-1; 75 mg L-1, e 100 mg L-1 de Benziladenina (BA, GA4+7 + Fenilmetil-aminopurina (GA4+7+CK, Ácido giberélico (GA3 e Cloreto de chlormequat (CCC. Avaliaram-se o comprimento e o diâmetro do caule, o número de folhas, o comprimento e a fitomassa seca de raíz, do caule, das folhas e total. Os dados foram submetidos à análise de variância e de regressão polinomial, sendo realizado desdobramento quando houve efeito significativo da interação.Os reguladores não promoveram respostas significativas para o comprimento e a massa seca de raiz, do caule, de folhas e total. Porém, GA4+7+Fenilmetil-aminopurina foi o regulador que incrementou o comprimento do caule, o diâmetro e o número de folhas, promovendo maior desenvolvimento às mudas e reduzindo o tempo para a formação do porta-enxerto, de três a oito meses, para dois meses (63 dias.The limiting main factor to the passion flower grafted seedlings production is the long time necessary for its formation. So, this work aimed, to evaluate the effects of vegetal regulators, at Passiflora alata Curtis seedlings development, aiming to reduce time for the seedling to reach the grafting point. The experimental design was completely randomized, with a 4 x 5 (plant growth regulator x concentrations factorial and four replicates, with 25 seedlings per parcel. The treatments were as follow: Benzyladenine, GA

  20. Allelopathy of Camelina sativa Boiss. (Brassicaceae on germination and early development of Bidens pilosa (L. and Glycine max (L. Merr

    Directory of Open Access Journals (Sweden)

    Jéssica da Silva

    2011-12-01

    Full Text Available This study evaluated the possible presence of allelopathic potential in camelina, as well as its effect on germination and early growth of soybean seedlings and beggarticks, in order, to verify the possibility of cultivating it with soybeans in a culture rotation system and its use as a herbicide. The experiments were carried out at the Laboratory of Plant Physiology of Universidade Estadual do Oeste do Paraná, Cascavel, Paraná, Brazil. The design was completely randomized and the evaluations were held daily. The parameters under analysis were: germination percentage, time and average speed of germination, and average root lenght. The data obtained underwent the F-Test and the mean values were compared through Tukey’s test, at a 5% probability level. The results confi rm the presence of allelopathic potential in camelina. It was found that this species can be considered an option for cultivating with soybean, due to the positive allelophatic interference caused in the culture and because it can be used in the control of weeds such as beggartick, having in mind that that it has delayed the development of the seedlings tested.

  1. Penicillin: its discovery and early development.

    Science.gov (United States)

    Ligon, B Lee

    2004-01-01

    In August 1928, Alexander Fleming returned from a vacation to his usually messy, disordered laboratory. In one of the Petri dishes that had not been touched by the Lysol, he noticed an unusual phenomenon: separate colonies of staphylococci and, near the dish's edge, a colony of mold approximately 20 mm in diameter. The finding proved to be a watershed in the history of medicine. This discovery lay dormant for some time before other researchers took up the challenge to investigate its clinical possibilities. Two investigators at Oxford, Sir Howard Walter Florey and Ernst Boris Chain, brought penicillin's potential for medical use to fruition and, along with Fleming, shared the 1945 Nobel Prize for Medicine. The discovery and development of penicillin represent one of the most important developments in the annals of medical history. This article presents a brief overview of the events that occurred in the progress from discovery to implementation as a therapeutic agent.

  2. Early development of Thyrsitops lepidopoides (Pisces: Gempylidae

    Directory of Open Access Journals (Sweden)

    Sato Gosuke

    1986-01-01

    Full Text Available Thyrsitops lepidopoides larvae were caught with Bongo nets in the upper 200 m of the ocean from the coast of southern Brazil during 1975-1978. Based on a serie of 271 specimens ranging from 2.5 to 24.0 mm body lenght, morphological and osteological development of the larvae and juveniles is described. Small larvae (2.5-12.0 mm NL can be distinguished from all known gempylid larvae by the presence of a distinct melanophore at the base of the dorsal and anal fins. The larvae have well developed dorsal and ventral spines. It is the only gempylid with six preopercular spines and non-serrated dorsal and ventral spines during the larval stage.

  3. Challenges in early clinical development of adjuvanted vaccines.

    Science.gov (United States)

    Della Cioppa, Giovanni; Jonsdottir, Ingileif; Lewis, David

    2015-06-08

    A three-step approach to the early development of adjuvanted vaccine candidates is proposed, the goal of which is to allow ample space for exploratory and hypothesis-generating human experiments and to select dose(s) and dosing schedule(s) to bring into full development. Although the proposed approach is more extensive than the traditional early development program, the authors suggest that by addressing key questions upfront the overall time, size and cost of development will be reduced and the probability of public health advancement enhanced. The immunogenicity end-points chosen for early development should be critically selected: an established immunological parameter with a well characterized assay should be selected as primary end-point for dose and schedule finding; exploratory information-rich end-points should be limited in number and based on pre-defined hypothesis generating plans, including system biology and pathway analyses. Building a pharmacodynamic profile is an important aspect of early development: to this end, multiple early (within 24h) and late (up to one year) sampling is necessary, which can be accomplished by sampling subgroups of subjects at different time points. In most cases the final target population, even if vulnerable, should be considered for inclusion in early development. In order to obtain the multiple formulations necessary for the dose and schedule finding, "bed-side mixing" of various components of the vaccine is often necessary: this is a complex and underestimated area that deserves serious research and logistical support.

  4. Early influences on the development of food preferences

    National Research Council Canada - National Science Library

    Ventura, Alison K; Worobey, John

    2013-01-01

    .... This early experience serves as the foundation for the continuing development of food preferences across the lifespan, and is shaped by the interplay of biological, social, and environmental factors...

  5. Metabolic gene profile in early human fetal heart development

    National Research Council Canada - National Science Library

    Iruretagoyena, J I; Davis, W; Bird, C; Olsen, J; Radue, R; Teo Broman, A; Kendziorski, C; Splinter BonDurant, S; Golos, T; Bird, I; Shah, D

    2014-01-01

    .... In order to describe normal cardiac development during late first and early second trimester in human fetuses this study used microarray and pathways analysis and created a corresponding 'normal' database...

  6. Early bilingualism, language attainment, and brain development.

    Science.gov (United States)

    Berken, Jonathan A; Gracco, Vincent L; Klein, Denise

    2017-04-01

    The brain demonstrates a remarkable capacity to undergo structural and functional change in response to experience throughout the lifespan. Evidence suggests that, in many domains of skill acquisition, the manifestation of this neuroplasticity depends on the age at which learning begins. The fact that most skills are acquired late in childhood or in adulthood has proven to be a limitation in studies aimed at determining the relationship between age of acquisition and brain plasticity. Bilingualism, however, provides an optimal model for discerning differences in how the brain wires when a skill is acquired from birth, when the brain circuitry for language is being constructed, versus later in life, when the pathways subserving the first language are already well developed. This review examines some of the existing knowledge about optimal periods in language development, with particular attention to the attainment of native-like phonology. It focuses on the differences in brain structure and function between simultaneous and sequential bilinguals and the compensatory mechanisms employed when bilingualism is achieved later in life, based on evidence from studies using a variety of neuroimaging modalities, including positron emission tomography (PET), task-based and resting-state functional magnetic resonance imaging (fMRI), and structural MRI. The discussion concludes with the presentation of recent neuroimaging studies that explore the concept of nested optimal periods in language development and the different neural paths to language proficiency taken by simultaneous and sequential bilinguals, with extrapolation to general notions of the relationship between age of acquisition and ultimate skill performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Immunity through early development of coral larvae.

    Science.gov (United States)

    Palmer, C V; Graham, E; Baird, A H

    2012-10-01

    As a determinant of survival, immunity is likely to be significant in enabling coral larvae to disperse and successfully recruit, however, whether reef-building coral larvae have immune defenses is unknown. We investigated the potential presence and variation in immunity in the lecithotrophic larvae of Acropora tenuis through larval development. Enzymes indicative of tyrosinase and laccase-type melanin-synthesis were quantified, and the concentration of three coral fluorescent proteins was measured over six developmental stages; egg, embryo, motile planula, planula post-exposure to crustose coralline algae (CCA; settlement cue), settled, settled post-exposure to Symbiodinium (endosymbiont). Both types of melanin-synthesis pathways and the three fluorescent proteins were present in A. tenuis throughout development. Laccase-type activity and red fluorescence increased following exposure of planula to CCA, whereas tyrosinase-type activity and cyan fluorescence increased following settlement. No change was detected in the measured parameters following exposure to Symbiodinium. This study is the first to document coral larval immune responses and suggests the melanin-synthesis pathways have disparate roles-the laccase-type potentially non-immunological and the tyrosinase-type in cytotoxic defense. Our results indicate that corals have the potential to resist infection from the earliest life history phase. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Assessment of early child development: what, why, and how?

    Directory of Open Access Journals (Sweden)

    Tajana Brajović

    2010-05-01

    Full Text Available Motor skills, language, social and personal development as well as cognitive abilities are often the focus of early child development assessment and monitoring. The article presents some of the developmental milestones in these areas of child development. At the same time the article demonstrates that early child development assessment surpasses merely the orientation acording to developmental milestones. As a part of primary health prevention in Slovenia, identification of children with potential developmental delays is performed with the Denver developmental screening test II and the Systematical psychological examination of the three-year-old procedure. The purpose of applying developmental screening tests is early identification of children with developmental problems, as well as preparation of effective early interventions. By applying an appropriate psychological test material, a psychologist is able to assess the type and the stage of child' s psychological problems and delays in different developmental domains. Only psychometrically sound, and standardized tests should be applied in the process of early child development assessment. The work presents some of the practical and theoretical difficulties which practitioners are facing in the process of early child development assessment. Some feasible solutions are provided as well.

  9. Early intestinal growth and development in poultry.

    Science.gov (United States)

    Lilburn, M S; Loeffler, S

    2015-07-01

    While there are many accepted "facts" within the field of poultry science that are in truth still open for discussion, there is little debate with respect to the tremendous genetic progress that has been made with commercial broilers and turkeys (Havenstein et al., 2003, 2007). When one considers the changes in carcass development in poultry meat strains, these genetic "improvements" have not always been accompanied by correlated changes in other physiological systems and this can predispose some birds to developmental anomalies (i.e. ascites; Pavlidis et al., 2007; Wideman et al., 2013). Over the last decade, there has been increased interest in intestinal growth/health as poultry nutritionists have attempted to adopt new approaches to deal with the broader changes in the overall nutrition landscape. This landscape includes not only the aforementioned genetic changes but also a raft of governmental policies that have focused attention on the environment (phosphorus and nitrogen excretion), consumer pressure on the use of antibiotics, and renewable biofuels with its consequent effects on ingredient costs. Intestinal morphology has become a common research tool for assessing nutritional effects on the intestine but it is only one metric among many that can be used and histological results can often be interpreted in a variety of ways. This study will address the broader body of research on intestinal growth and development in commercial poultry and will attempt to integrate the topics of the intestinal: microbial interface and the role of the intestine as an immune tissue under the broad umbrella of intestinal physiology. © 2015 Poultry Science Association Inc.

  10. Developmental reaction norms for water stressed seedlings of succulent cacti.

    Science.gov (United States)

    Rosas, Ulises; Zhou, Royce W; Castillo, Guillermo; Collazo-Ortega, Margarita

    2012-01-01

    Succulent cacti are remarkable plants with capabilities to withstand long periods of drought. However, their adult success is contingent on the early seedling stages, when plants are highly susceptible to the environment. To better understand their early coping strategies in a challenging environment, two developmental aspects (anatomy and morphology) in Polaskia chichipe and Echinocactus platyacanthus were studied in the context of developmental reaction norms under drought conditions. The morphology was evaluated using landmark based morphometrics and Principal Component Analysis, which gave three main trends of the variation in each species. The anatomy was quantified as number and area of xylem vessels. The quantitative relationship between morphology and anatomy in early stages of development, as a response to drought was revealed in these two species. Qualitatively, collapsible cells and collapsible parenchyma tissue were observed in seedlings of both species, more often in those subjected to water stress. These tissues were located inside the epidermis, resembling a web of collapsible-cell groups surrounding turgid cells, vascular bundles, and spanned across the pith. Occasionally the groups formed a continuum stretching from the epidermis towards the vasculature. Integrating the morphology and the anatomy in a developmental context as a response to environmental conditions provides a better understanding of the organism's dynamics, adaptation, and plasticity.

  11. Developmental reaction norms for water stressed seedlings of succulent cacti.

    Directory of Open Access Journals (Sweden)

    Ulises Rosas

    Full Text Available Succulent cacti are remarkable plants with capabilities to withstand long periods of drought. However, their adult success is contingent on the early seedling stages, when plants are highly susceptible to the environment. To better understand their early coping strategies in a challenging environment, two developmental aspects (anatomy and morphology in Polaskia chichipe and Echinocactus platyacanthus were studied in the context of developmental reaction norms under drought conditions. The morphology was evaluated using landmark based morphometrics and Principal Component Analysis, which gave three main trends of the variation in each species. The anatomy was quantified as number and area of xylem vessels. The quantitative relationship between morphology and anatomy in early stages of development, as a response to drought was revealed in these two species. Qualitatively, collapsible cells and collapsible parenchyma tissue were observed in seedlings of both species, more often in those subjected to water stress. These tissues were located inside the epidermis, resembling a web of collapsible-cell groups surrounding turgid cells, vascular bundles, and spanned across the pith. Occasionally the groups formed a continuum stretching from the epidermis towards the vasculature. Integrating the morphology and the anatomy in a developmental context as a response to environmental conditions provides a better understanding of the organism's dynamics, adaptation, and plasticity.

  12. Muskmelon seed germination and seedling development in response to seed priming Germinação de sementes e desenvolvimento de plântulas de melão em resposta ao condicionamento osmótico

    Directory of Open Access Journals (Sweden)

    Warley Marcos Nascimento

    2003-02-01

    Full Text Available Important factors affecting seed priming have not been extensively reported in muskmelon (Cucumis melo L. studies. The optimization of the seed priming technique becomes very important at the commercial scale. Little information has been reported on seedling development of muskmelon subsequent to seed priming. Seeds of muskmelon were primed in darkness at 25°C in different solutions and three osmotic potentials. Seeds were also primed with and without aeration during different periods. In relation to osmotic solutions, an osmotic potential around -1.30 MPa is most adequate for muskmelon priming. Salt solutions gave better germination rate but were deleterious for seed germination, especially at higher osmotic potentials. Aeration of the soaking salt solution gave faster germination at 17°C, and because of the early germination, these treatments probably presented a better seedling development. Deleterious effect on total seed germination was observed for long soaking periods with aeration. Fungal growth increased on seeds primed in aerated solutions. Seeds from priming treatments had a better germination rate and seedling development under 17 and 25°C.Importantes fatores afetando o condicionamento osmótico não têm sido extensivamente relatados em sementes de melão (Cucumis melo L.. A otimização do condicionamento osmótico é extremamente importante em uma escala comercial. Poucas informações têm sido relatadas quanto ao desenvolvimento de plântulas em resposta ao condicionamento osmótico de sementes de melão. Sementes de melão foram condicionadas a 25°C, na ausência de luz, em diferentes soluções osmóticas utilizando três potenciais osmóticos para cada solução. Em outro estudo, sementes foram condicionadas com ou sem aeração durante vários períodos. Indiferentemente das soluções osmóticas, o potencial osmótico em torno de - 1,30 MPa foi mais adequado para o condicionamento osmótico. Sementes condicionadas em

  13. Early vegetation development on an exposed reservoir: implications for dam removal.

    Science.gov (United States)

    Auble, Gregor T; Shafroth, Patrick B; Scott, Michael L; Roelle, James E

    2007-06-01

    The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition.

  14. Thermal Requirements of Development Phases and Simulation Model for Watermelon Seedlings%西瓜幼苗发育阶段热量需求及模型模拟

    Institute of Scientific and Technical Information of China (English)

    李彭丽; 陈罡晓; 牛庆良; 黄丹枫; 孙治强

    2015-01-01

    通过5次穴盘育苗试验,量化了西瓜幼苗各生育阶段的累积热量单位需求,西瓜幼苗出苗期、子叶展平期、1片真叶期、2片真叶期、3片真叶期、3叶1心期平均所需的累积热量单位分别为2451.02、639.71、2240.85、1916.65、1802.19、670.22℃·h,完成整个苗期所需的累积热量单位为9720.64℃·h;基于累积热量单位驱动,构建了西瓜幼苗发育阶段模拟模型,检测结果表明,模型精度良好。%We conducted five seedling-raising experiments in plugs and quantified the thermal requirements of different development phases for watermelon seedlings. The results showed that, the accumulated thermal units were 2 451.02, 639.71, 2 240.85, 1 916.65, 1 802.19 and 670.22 ℃·h for seedling emergence phase, cotyledon spreading phase, one-leaf phase, two-leaf phase, three-leaf phase and three-leaf with one-shoot phase respectively, and total accumulated thermal unit was 9 720.64 ℃·h to accomplish the whole seedling phase. Based on accumulated thermal unit, we built a simulation model for development phases of watermelon seedlings, and the testing results showed that, the model possessed higher accuracy and practicality.

  15. The yolk syncytial layer in early zebrafish development.

    Science.gov (United States)

    Carvalho, Lara; Heisenberg, Carl-Philipp

    2010-10-01

    The yolk syncytial layer (YSL) plays crucial roles in early zebrafish development. The YSL is a transient extra-embryonic syncytial tissue that forms during early cleavage stages and persists until larval stages. During gastrulation, the YSL undergoes highly dynamic movements, which are tightly coordinated with the movements of the overlying germ layer progenitor cells, and has critical functions in cell fate specification and morphogenesis of the early germ layers. Movement coordination between the YSL and blastoderm cells is dependent on contact between these tissues, and is probably required for the patterning and morphogenetic function of the YSL. In this review, we will discuss recent advances in elucidating the molecular and cellular mechanisms underlying the YSL morphogenesis and movement coordination between the YSL and blastoderm during early development.

  16. Early life origins of psychological development and mental health.

    Science.gov (United States)

    Räikkönen, Katri; Pesonen, Anu-Katriina

    2009-12-01

    According to the Developmental Origins of Health and Disease (DOHaD)-hypothesis, conditions early in life may have life-long consequences. In a series of epidemiological birth cohort and clinical studies and natural experiments, we have had the chance to test the extent to which this hypothesis is useful in understanding individual differences in psychological development and mental health. Our findings have provided evidence that individual differences in cognitive, social and emotional development and in mental health may lie in early life circumstances, and add significantly to the literature by pointing out which periods of early growth are the most critical. These findings are also important in translating pre-clinical evidence to humans. What remains less clear, however, is what the mechanisms of programming are. Thus, further research is needed to elucidate these mechanisms before information on the early life origins of health and disease can be used in designing prevention and intervention programs.

  17. Early Brain and Child Development: Connections to Early Education and Child Care

    Science.gov (United States)

    Romano, Judith T.

    2013-01-01

    The vast majority of young children spend time in settings outside of the home, and the nature of those settings directly impacts the child's health and development. The ecobiodevelopmental framework of early brain and child development serve as the backdrop for establishing quality. This article describes the use of quality rating systems,…

  18. Integrated and Early Childhood Education: Preparation for Social Development. Theme A: Relevant Provision for Early Childhood.

    Science.gov (United States)

    Axton, J. H. M.

    Factors which influence child development are listed and briefly discussed. These factors are (1) mother's childhood, (2) mother's age, (3) care during pregnancy and delivery, (4) early neonatal factors, (5) birth interval, (6) effect of repeated infection and malnutrition on brain growth and intellectual development, and (7) home environment. The…

  19. Early Brain and Child Development: Connections to Early Education and Child Care

    Science.gov (United States)

    Romano, Judith T.

    2013-01-01

    The vast majority of young children spend time in settings outside of the home, and the nature of those settings directly impacts the child's health and development. The ecobiodevelopmental framework of early brain and child development serve as the backdrop for establishing quality. This article describes the use of quality rating systems,…

  20. Desenvolvimento de mudas de pupunheira em Latossolo argiloso compactado artificialmente em subsuperfície Peach palm seedlings development in artificiality subsurface compacted clayly Latossol

    Directory of Open Access Journals (Sweden)

    Ivan Bordin

    2006-02-01

    Full Text Available O trabalho teve como objetivo avaliar o desenvolvimento de mudas de pupunheira (Bactris gasipaes H.B.K. cultivadas em amostras de um Latossolo Vermelho eutroférrico de textura argilosa compactado artificialmente em subsuperfície. As amostras de solo que foram compactadas a quatro níveis de densidade (1,0; 1,13; 1,28 e 1,44kg dm-3 estavam nas camadas intermediárias de 3,5cm de vasos de PVC de 20cm de diâmetro, que constavam de outras camadas superiores de 15cm e inferiores de 10cm. As avaliações foram realizadas em quatro épocas (4, 6, 8 e 10 meses. O aumento dos níveis de densidade do solo não influenciou no desenvolvimento da parte aérea das mudas de pupunheira. Independentemente da época estudada, os níveis de densidade do Latossolo argiloso não impediram a penetração das raízes da pupunheira.This study was carried out to evaluate the development of peach palm (Bactris gasipaes H.B.K. seedlings submitted to artificiality subsurface compacted layers of a clayly texture eutroferric Red Latossol. The compacted soil was at the middle ring of the PVC pots. They were 20cm of diameter, divided in tree rings with 15; 3,5 and 10cm from the up side. The soil was submitted to four density levels (1,0; 1,13; 1,28 and 1,44kg dm-3, which determined the treatments. The evaluations were accomplished in four times (4, 6, 8 and 10 months. The increase of the soil density levels didn't influence in the development of the aerial part of the peach palm seedlings. Independent of the studied time, the clayly Latossol density levels, didn't prevent the peach palm roots penetration.

  1. Development of seedlings of red pitaya (Hylocereus undatus Haw in different substrate volumes = Desenvolvimento de mudas de pitaya vermelha (Hylocereus undatus Haw em diferentes volumes de substrato

    Directory of Open Access Journals (Sweden)

    Renata Aparecida de Andrade

    2008-12-01

    Full Text Available With the ever-increasing search for alternatives by producers and demand for exotic fruits by consumers, the market for fruits species has grown considerably. In this context, the pitaya has been sought not only for its exotic appearance, but also for its organoleptic characteristics. The present research was conducted with the objective of evaluating the influence of the substrate volume in the development of seedlings of red pitaya, by using polystyrene trays expanded with different volumes of cells: 10, 15, 30 and 65 mL. The evaluations, conducted during 90 days, evaluated: survival percentage; number and height of stems (cm; largest root length (cm; fresh and dry masses of the stems and roots (g. The delineation was entirely randomized. The values of survival percentage were transformed in arc sin and the averages were compared by the Tukey test at 5%. The survival and vegetative development for seedlings of red pitaya were directly proportional to the volume of the substrate used. In order to form seedlings of red pitaya from seeds, the use of containers with 65 mL of capacity is recommended.Com a procura cada vez maior de alternativas por parte dos produtores rurais e de frutas exóticas pelos consumidores, o mercado de frutíferas tem crescido consideravelmente. Neste contexto, a pitaya vem sendo procurada não apenas pelo exotismo de sua aparência, como também por suas características organoléticas. O presente trabalho foi realizado objetivando avaliar a influência do volume de substrato no desenvolvimento de mudas de pitaya vermelha, utilizando-se bandejas de poliestireno expandido com diferentes volumes de células: 10, 15, 30 e 65 mL. As avaliações, realizadas aos 90 dias, foram quanto: porcentagem de sobrevivência; ao número e altura doscladódios (cm, ao comprimento da maior raiz (cm; às massas fresca e seca dos cladódios e das raízes (gramas. O delineamento experimental foi inteiramente casualizado. Os dados de

  2. Genetic diversity of seagrass seeds influences seedling morphology and biomass.

    Science.gov (United States)

    Randall Hughes, A; Hanley, Torrance C; Schenck, Forest R; Hays, Cynthia G

    2016-12-01

    Genetic diversity can influence ecological processes throughout ontogeny, yet whether diversity at early life history stages is important in long-lived taxa with overlapping generations is unclear. Seagrass systems provide some of the best evidence for the ecological effects of genetic diversity among adult shoots, but we do not know if the genetic diversity of seeds and seedlings also influences seagrass ecology. We tested the effects of seagrass (Zostera marina) seed diversity and relatedness on germination success, seedling morphology, and seedling production by comparing experimental assemblages of seeds collected from single reproductive shoots ("monocultures") to assemblages of seeds collected from multiple reproductive shoots ("polycultures"). There was no difference in seedling emergence, yet seedlings from polycultures had larger shoots above and below ground than seedlings from monocultures at the end of the 1-yr experiment. Genetic relatedness of the seedlings predicted some aspects of shoot morphology, with more leaves and longer roots and shoots at intermediate levels of relatedness, regardless of seed diversity. Our results suggest that studies of only adult stages may underestimate the importance of genetic diversity if the benefits at early life history stages continue to accrue throughout the life cycle. © 2016 by the Ecological Society of America.

  3. The APX4 locus regulates seed vigor and seedling growth in Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Ya-Ying; Hecker, Amanda G; Hauser, Bernard A

    2014-04-01

    The amino acid sequence of APX4 is similar to other ascorbate peroxidases (APXs), a group of proteins that protect plants from oxidative damage by transferring electrons from ascorbate to detoxify peroxides. In this study, we characterized two apx4 mutant alleles. Translational fusions with GFP indicated APX4 localizes to chloroplasts. Both apx4 mutant alleles formed chlorotic cotyledons with significantly reduced chlorophyll a, chlorophyll b and lutein. Given the homology of APX to ROS-scavenging proteins, this result is consistent with APX4 protecting seedling photosystems from oxidation. The growth of apx4 seedlings was stunted early in seedling development. In addition, APX4 altered seed quality by affecting seed coat formation. While apx4 seed development appeared normal, the seed coat was darker and more permeable than the wild type. In addition, accelerated aging tests showed that apx4 seeds were more sensitive to environmental stress than the wild-type seeds. If APX4 affects seed pigment biosynthesis or reduction, the seed coat color and permeability phenotypes are explained. apx4 mutants had cotyledon chlorosis, increased H₂O₂ accumulation, and reduced soluble APX activity in seedlings. These results indicate that APX4 is involved in the ROS-scavenging process in chloroplasts.

  4. Early physiological responses of Pinus pinea L. seedlings infected by Heterobasidion sp.pl. in an ozone-enriched atmospheric environment.

    Science.gov (United States)

    Pollastrini, Martina; Luchi, Nicola; Michelozzi, Marco; Gerosa, Giacomo; Marzuoli, Riccardo; Bussotti, Filippo; Capretti, Paolo

    2015-03-01

    The presence of the American root-rot disease fungus Heterobasidion irregulare Garbel. & Otrosina was detected in Italian coastal pine forests (Pinus pinea L.) in addition to the common native species Heterobasidion annosum (Fries) Brefeld. High levels of tropospheric ozone (O3) as an atmospheric pollutant are usually experienced in Mediterranean pine forests. To explore the effect of interaction between the two Heterobasidion species and ozone pollution on P. pinea, an open-top chamber (OTC) experiment was carried out. Five-year-old P. pinea seedlings were inoculated with the fungal species considered (H. irregulare, H. annosum and mock-inoculation as control), and then exposed in charcoal-filtered open-top chambers (CF-OTC) and non-filtered ozone-enriched chambers (NF+) from July to the first week of August 2010 at the experimental facilities of Curno (North Italy). Fungal inoculation effects in an ozone-enriched environment were assessed as: (i) the length of the inoculation lesion; (ii) chlorophyll a fluorescence (ChlF) responses; and (iii) analysis of resin terpenes. Results showed no differences on lesion length between fungal and ozone treatments, whereas the short-term effects of the two stress factors on ChlF indicate an increased photosynthetic efficiency, thus suggesting the triggering of compensation/repair processes. The total amount of resin terpenes is enhanced by fungal infection of both species, but depressed by ozone to the levels observed in mock-inoculated plants. Variations in terpene profiles were also induced by stem base inoculations and ozone treatment. Ozone might negatively affect terpene defences making plants more susceptible to pathogens and insects.

  5. Overcoming seed dormancy and early growth of seedlings of Spondias tuberosa, Arr. CâmaraSuperação de dormência de sementes e crescimento inicial de plântulas de umbuzeiro

    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

  6. Understanding Emotional Development: Helping Early Childhood Providers Better Support Families

    Science.gov (United States)

    Edwards, Nicole Megan

    2012-01-01

    This article is intended to provide early childhood providers with a concise overview of emerging emotional development in young children (birth-5), the important role of primary caregivers, and the link between parenting, emotional development, and behavior. Specific suggestions that have been shared with urban Head Start mothers are offered,…

  7. Early Markers of Vulnerable Language Skill Development in Galactosaemia

    Science.gov (United States)

    Lewis, Fiona M.; Coman, David J.; Syrmis, Maryanne

    2014-01-01

    There are no known biomedical or genetic markers to identify which infants with galactosaemia (GAL) are most at risk of poor language skill development, yet pre-linguistic communicative "red flag" behaviours are recognised as early identifiers of heightened vulnerability to impaired language development. We report on pre-linguistic…

  8. Early Markers of Vulnerable Language Skill Development in Galactosaemia

    Science.gov (United States)

    Lewis, Fiona M.; Coman, David J.; Syrmis, Maryanne

    2014-01-01

    There are no known biomedical or genetic markers to identify which infants with galactosaemia (GAL) are most at risk of poor language skill development, yet pre-linguistic communicative "red flag" behaviours are recognised as early identifiers of heightened vulnerability to impaired language development. We report on pre-linguistic…

  9. Time Development in the Early History of Social Networks

    DEFF Research Database (Denmark)

    Bruun, Jesper; Bearden, Ian

    2014-01-01

    Studies of the time development of empirical networks usually investigate late stages where lasting connections have already stabilized. Empirical data on early network history are rare but needed for a better understanding of how social network topology develops in real life. Studying students w...

  10. Early Learning and Development: Cultural-Historical Concepts in Play

    Science.gov (United States)

    Fleer, Marilyn

    2010-01-01

    "Early Learning and Development" provides a unique synthesis of cultural-historical theory from Vygotsky, Elkonin and Leontiev in the 20th century to the ground-breaking research of scholars such as Siraj-Blatchford, Kratsova and Hedegaard today. It demonstrates how development and learning are culturally embedded and institutionally defined, and…

  11. Evaluation of Promalin to promote growth of young mangosteen seedlings

    Science.gov (United States)

    A major impediment to the development of a mangosteen (Garcinia mangostana L.) industry is the long pre-bearing stage that seedlings take to produce fruits. A field study was conducted to determine the effect of Promalin on the growth of mangosteen seedlings. Promalin was applied as a foliar spray...

  12. Efeito do fósforo no desenvolvimento inicial de mudas de goiabeira serrana Effect of phosphorus on the initial development of feijoa seedlings

    Directory of Open Access Journals (Sweden)

    J.C. Nachtigal

    1994-08-01

    Full Text Available Foi estudado o efeito da adubação fosfatada no desenvolvimento inicial de mudas de goiabeira serrana (Feijoa sellowiana Berg. num experimento em vasos, com solo Podzólico Vermelho Amarelo, apresentando 4 ppm de P extraível pelo método de Mehlich. Os níveis de fósforo utilizados foram 0, 50, 100 e 150 ppm de P, aplicados antes da instalação do experimento, juntamente com 150 ppm de K. Em cobertura, foram aplicados 150 ppm de N, em três parcelas iguais aos 7, 27 e 47 dias após a repicagem das mudas. Plântulas oriundas de sementes de plantas nativas, com aproximadamente 30 dias, foram transplantadas para os vasos e cultivadas durante 89 dias. Houve efeito significativo do P sobre todas as variáveis analisadas. A altura das plantas mostrou um comportamento similar à curva clássica do crescimento, mas os incrementos obtidos a cada avaliação aumentaram com os níveis de P. A matéria seca das raízes e da parte aérea, bem como as quantidades extraídas de N, P e K aumentaram linearmente com os níveis de P. O teor de P no tecido aumentou até o nível de 50 ppm de P aplicado, permanecendo estável nos níveis maiores, enquanto os de N e K diminuiram nos níveis acima de 50 ppm de P. Os resultados obtidos permitem verificar a elevada exigência de fósforo desta espécie no período inicial de crescimento.The effect of phosphate fertilization on the initial development of feijoa (Feyoa sellowiana Berg. seedlings was studied in a pot experiment with a Red Yellow Podzolk soil having 4 ppm of extractable phosporous by the Mehlich method. Levels of phosphorous of 0, 50, 100 and 150 ppm together with 150 ppm of K were applied as a basal dressing. In three equal portions 150 ppm of N were applied at 7, 27 and 42 days after the transplant of the seedlings. Seedlings of native plants, with 30 days approximately, were transplanted to pots and cultivated during 89 days. There was a significant effect of phosphorous on all analised variables

  13. Massa de sementes e profundidades de semeadura no desenvolvimento de mudas de tamarindeiro Seeds weight and sowing depths in the development of tamarind seedlings

    Directory of Open Access Journals (Sweden)

    Marcelo Sales de Almeida

    2010-06-01

    indicated that the weighty seeds yield the best seedlings initial development. There were no significant differences in the parameters evaluated as a function of sowing depth.

  14. Time Development in the Early History of Social Networks

    DEFF Research Database (Denmark)

    Bruun, Jesper; Bearden, Ian

    2014-01-01

    Studies of the time development of empirical networks usually investigate late stages where lasting connections have already stabilized. Empirical data on early network history are rare but needed for a better understanding of how social network topology develops in real life. Studying students who...... are beginning their studies at a university with no or few prior connections to each other offers a unique opportunity to investigate the formation and early development of link patterns and community structure in social networks. During a nine week introductory physics course, first year physics students were...... asked to identify those with whom they communicated about problem solving in physics during the preceding week. We use these students' self reports to produce time dependent student interaction networks. We investigate these networks to elucidate possible effects of different student attributes in early...

  15. Early feeding practices and development of food allergies.

    Science.gov (United States)

    Lack, Gideon; Penagos, Martin

    2011-01-01

    Despite increasing efforts to prevent food allergies in children, IgE-mediated food allergies continue to rise in westernized countries. Previous preventive strategies such as prolonged exclusive breastfeeding and delayed weaning onto solid foods have more recently been called into question. The present review discusses possible risk factors and theories for the development of food allergy. An alternative hypothesis is proposed, suggesting that early cutaneous exposure to food protein through a disrupted skin barrier leads to allergic sensitization and that early oral exposure of food allergen induces tolerance. Novel interventional strategies to prevent the development of food allergies are also discussed.

  16. The Big Push: Early Development Economics (1945-1975)

    OpenAIRE

    Kartika, Dwintha Maya

    2014-01-01

    This article attempts to analyse the strategies, strengths and weaknesses of early development economics, commonly known as the Big Push era. The article starts with the historical analysis on what could influence the thinking of structuralist approach to development. The next section highlights the common strategies proposed by the development pioneers. This is followed by the assessment of industrialisation strategies based on their strengths and weaknesses of the strategies proposed. Final...

  17. Developing the quality of early childhood mentoring institutions

    Directory of Open Access Journals (Sweden)

    Sri Hartini

    2017-09-01

    Full Text Available The study was to uncover the concept of quality improvement, the supporting and the inhibiting factors within the quality improve and the quality improvement in the early childhood mentoring institutions/kindergarten. The study was a qualitative research. The subjects in the study were kindergarten principals, kindergarten teachers and parents. The data were gathered by means of observation, interview and documentation. For the data analysis, the researcher selected the qualitative descriptive data analysis method. The results of the study were as follows. First, the concept of educational quality improvement in the early childhood mentoring institutions/ kindergarten has been improveed from the vision, the mission and the objectives and the concept includes the aspects of planning, process and output which has synergy from one to another. The planning has been formulated in the curriculum, the syllabus and the daily activity plan. Second, the approach, the strategy and the technique of quality improvement has maximized the well-qualified schools’ resources, have been supported by the sufficient facilities and have been funded by the sufficient budget. Third, the supporting factors within the quality improvement of early childhood mentoring institutions/kindergarten have been the increasing awareness within the society toward the significance of early childhood mentoring institutions, the massive socialization conducted by the Office of Education through the provision of training programs in relation to the early childhood mentoring institution/kindergarten management and the human resources empowerment toward developing the quality of early childhood mentoring institutions. Fourth, the inhibiting factors within the quality improvement of early childhood mentoring institutions have been the lack of society care and participation, the less quality human resources that early childhood mentoring institutions have, the fund limitation, the

  18. Temperament, Executive Control, and ADHD across Early Development

    Science.gov (United States)

    Rabinovitz, Beth B.; O’Neill, Sarah; Rajendran, Khushmand; Halperin, Jeffrey M.

    2015-01-01

    Research examining factors linking early temperament and later ADHD is limited by cross-sectional approaches and having the same informant rate both temperament and psychopathology. We used multi-informant/multi-method longitudinal data to test the hypothesis that negative emotionality during preschool is positively associated with ADHD symptom severity in middle childhood, but developing executive control mediates this relation. Children (N=161) with and without ADHD were evaluated three times: Parent and teacher temperament ratings and NEPSY Visual Attention at ages 3–4 years; WISC-IV Working Memory Index and NEPSY Response Set at age 6 years; and ADHD symptoms using the Kiddie-SADS at age 7 years. Parent and teacher ratings of preschoolers’ temperament were combined to form an Anger/Frustration composite. Similarly, an Executive Functioning composite was derived from age 6 measures. Bootstrapping was used to determine whether age 6 Executive Functioning mediated the relation between early Anger/Frustration and later ADHD symptom severity, while controlling for early executive functioning. Preschoolers’ Anger/Frustration was significantly associated with later ADHD symptoms, with this relation partially mediated by age 6 Executive Functioning. Developing executive control mediates the relation between early Anger/Frustration and later ADHD symptom severity, suggesting that Anger/Frustration influences ADHD symptom severity through its impact on developing executive control. Early interventions targeting the harmful influences of negative emotionality or enhancing executive functioning may diminish later ADHD severity. PMID:26854505

  19. Repression of Seed Maturation Genes by a Trihelix Transcriptional Repressor in Arabidopsis Seedlings[W

    Science.gov (United States)

    Gao, Ming-Jun; Lydiate, Derek J.; Li, Xiang; Lui, Helen; Gjetvaj, Branimir; Hegedus, Dwayne D.; Rozwadowski, Kevin

    2009-01-01

    The seed maturation program is repressed during germination and seedling development so that embryonic genes are not expressed in vegetative organs. Here, we describe a regulator that represses the expression of embryonic seed maturation genes in vegetative tissues. ASIL1 (for Arabidopsis 6b-interacting protein 1-like 1) was isolated by its interaction with the Arabidopsis thaliana 2S3 promoter. ASIL1 possesses domains conserved in the plant-specific trihelix family of DNA binding proteins and belongs to a subfamily of 6b-interacting protein 1-like factors. The seedlings of asil1 mutants exhibited a global shift in gene expression to a profile resembling late embryogenesis. LEAFY COTYLEDON1 and 2 were markedly derepressed during early germination, as was a large subset of seed maturation genes, such as those encoding seed storage proteins and oleosins, in seedlings of asil1 mutants. Consistent with this, asil1 seedlings accumulated 2S albumin and oil with a fatty acid composition similar to that of seed-derived lipid. Moreover, ASIL1 specifically recognized a GT element that overlaps the G-box and is in close proximity to the RY repeats of the 2S promoters. We suggest that ASIL1 targets GT-box–containing embryonic genes by competing with the binding of transcriptional activators to this promoter region. PMID:19155348

  20. 北京花卉种苗产业现状分析与发展策略%Present Situation Analysis and Development Strategy on Flower Seedling Industrialization of Popular Flowers Variety in Beijing

    Institute of Scientific and Technical Information of China (English)

    李子敬; 陈晓; 董爱香; 衣彩洁; 丛日晨

    2015-01-01

    笔者论述了种苗产业化的主要组成要素,并综合分析国内外种苗产业现状,分析认为北京种苗产业发展的问题主要涉及缺乏自主知识产权新品种、产业链条不完善、法律法规不健全、销售模式单一化、服务和标准体系不完善、产学研联合体不健全等方面,并有针对性地提出了发展北京种苗产业的发展策略,主要包括转变政府职能并加强调控、发展北京特色花卉品种、细化产业分工、构建花卉种苗质量标准体系和认证机构、开展服务体系建设及建立产学研综合体等主要对策等,旨在为北京市种苗产业化发展提供决策依据。%Essential factors of flower seedling industrialization were discussed in this paper. The results indicated that the problems of flower industry in Beijing were deficiency of independent intellectual flower variety, incomplete flower industrial linking, unsoundness of law and regulation, simple model of sale, imperfect system of service and standard, and deficient of production-college-research union. Strategies of developing flower seedling industry were suggested, such us reinforcing government regulation, cultivating Beijing-characteristic flower variety, refining industrial division, establishment of flower seedlings quality standard system and certification institutions, developing service system and establishing flower seedling consortium, on the base of the analysis of international flower seedling situation, in order to provide policy-decision basis for flower seedling industrialization.

  1. Successional development from stands of Miscanthus sinensis to stands of Pinus densiflora and elements of microclimates: The seed germination and seedling establishment conditions of P. densiflora

    Science.gov (United States)

    Kashiwagi, Y.

    1991-09-01

    The succession mechanism from stands of Miscanthus sinensis to stands of Pinus densiflora was studied in relation to elements of microclimates within those plant communities. Laboratory experiments indicated that the seed germination of P. densiflora occurred at cumulative soil temperature between 75 °C ṡ day and 200 °C ṡ day. It is assumed from field research that establishment of P. densiflora seedlings is impossible if the effective cumulative air temperature at a height of 6 cm is less than 2,000 °C day, and the cumulative solar radiation figure totals less than 633 MJ/m2. The seedlings thrived in a M. sinensis stand growing on gently convex topography, which fulfills the requisites mentioned above. The seedlings in a M. sinensis stand growing on gently concave topography and in a P. densiflora stand died completely by October.

  2. Predictors of Early versus Later Spelling Development in Danish

    Science.gov (United States)

    Nielsen, Anne-Mette Veber; Juul, Holger

    2016-01-01

    The present study examined phoneme awareness, phonological short term memory, letter knowledge, rapid automatized naming (RAN), and visual-verbal paired associate learning (PAL) as longitudinal predictors of spelling skills in an early phase (Grade 2) and a later phase (Grade 5) of development in a sample of 140 children learning to spell in the…

  3. Changing the Perspective on Early Development of Rett Syndrome

    Science.gov (United States)

    Marschik, Peter B.; Kaufmann, Walter E.; Sigafoos, Jeff; Wolin, Thomas; Zhang, Dajie; Bartl-Pokorny, Katrin D.; Pini, Giorgio; Zappella, Michele; Tager-Flusberg, Helen; Einspieler, Christa; Johnston, Michael V.

    2013-01-01

    We delineated the achievement of early speech-language milestones in 15 young children with Rett syndrome ("MECP2" positive) in the first two years of life using retrospective video analysis. By contrast to the commonly accepted concept that these children are normal in the pre-regression period, we found markedly atypical development of…

  4. Early Intervention and Its Effects on Maternal and Child Development.

    Science.gov (United States)

    Slaughter, Diana T.

    1983-01-01

    The longitudinal study reported used an intervention strategy to test the thesis that sociocultural background, mediated by maternal attitudes and behaviors, influences Black children's early development in educationally significant ways. Two models of parent education were contrasted: the Levenstein toy demonstration program and the…

  5. Early Journals and Their Influences on the Development of Gerontology

    Science.gov (United States)

    Mercer, Lorraine; Carter, Lorraine

    2012-01-01

    This examination of early gerontology journals identifies the multidisciplinary backgrounds of contributors, methods of investigation, nascent theory development, and formative themes and controversies. Through use of content, thematic, and critical analyses of second year issues of "The Gerontologist," "Educational Gerontology," "Research on…

  6. Early Childhood Education for Sustainability: Recommendations for Development

    Science.gov (United States)

    Daries, Julie; Engdahl, Ingrid; Otieno, Lorraine; Pramling-Samuelson, Ingrid; Siraj-Blatchford, John; Vallabh, Priya

    2009-01-01

    The following recommendations for "Education for Sustainable Development (ESD)" in Early Childhood Education were the product of an extended international collaboration that was supported by a number of bodies including the Centre for Environment and Sustainability in Gothenburg, the Swedish Ministry of Education and Research, the…

  7. Early Childhood Traumatic Brain Injuries: Effects on Development and Interventions.

    Science.gov (United States)

    Lowenthal, Barbara

    1998-01-01

    Describes the variety of possible effects of traumatic brain injuries (TBI) on early childhood development in the cognitive, language, social-emotional, motor, and adaptive domains. Suggests interventions which can assist young survivors and their families. Suggests that more long-term, intensive studies be conducted on the short- and long-term…

  8. Early Journals and Their Influences on the Development of Gerontology

    Science.gov (United States)

    Mercer, Lorraine; Carter, Lorraine

    2012-01-01

    This examination of early gerontology journals identifies the multidisciplinary backgrounds of contributors, methods of investigation, nascent theory development, and formative themes and controversies. Through use of content, thematic, and critical analyses of second year issues of "The Gerontologist," "Educational Gerontology," "Research on…

  9. Career Planning and Development for Early-Career Scientists

    Science.gov (United States)

    Early career development can be looked at as being of two major phases. The first phase is the formal educational process leading to an awarded degree, postdoctoral training, and potentially formal certification in a scientific discipline. The second phase is the informal educa...

  10. Regionalism and Development in Early Nineteenth Century Spanish America.

    Science.gov (United States)

    Friedman, Douglas

    An understanding of regionalism in early 19th century Spanish America is crucial to any understanding of this region's economic development. Regionalism became the barrier to the kind of integrated national economy that some writers claim could have been implemented had it not been for the imposition of dependency by external forces. This…

  11. More Alike than Different: Early Childhood Professional Development in Guatemala

    Science.gov (United States)

    Hardin, Belinda J.; Vardell, Rosemarie; de Castaneda, Albertina

    2008-01-01

    This article describes an early childhood professional development project that took place in the summer of 2005 in Guatemala City. Located in Central America, Guatemala has a population of approximately 12.3 million people, including more than two million children under the age of 5 (UNESCO Institute for Statistics, 2007; UNICEF, 2004). Events…

  12. Developing Early Undergraduate Research at a Two-Year College

    Science.gov (United States)

    Sibbernsen, Kendra

    2013-01-01

    Two-year college (TYC) physics teachers are not often required to provide student research experiences as a part of their contracted duties. However, some TYC physics faculty members are interested in developing research opportunities for their freshman- and sophomore-level students, often called "early undergraduate research" (EUR).…

  13. Early Embryo Survival and Development in Sows with Lactational Ovulation

    NARCIS (Netherlands)

    Gerritsen, R.; Soede, N.M.; Langendijk, P.; Taverne, M.A.M.; Kemp, B.

    2008-01-01

    During lactation, daily separation of sow and piglets, intermittent suckling (IS), can induce lactational oestrus and ovulation. This study examined effects of IS on subsequent early embryo survival and development. Multiparous Topigs40 sows were separated from their piglets for either 12 consecutiv

  14. Impact of early pregnancy on prenatal development in the pig

    NARCIS (Netherlands)

    Lende, van der T.

    1989-01-01

    In the present study aspects of the impact of early pregnancy on the average prenatal development per litter and on the within-litter weight distribution at birth have been investigated. The aims of the present study are given in the introduction (chapter 1). A brief review of the literatur

  15. Illumina Spin-off to Develop Early-Detection Test.

    Science.gov (United States)

    Colwell, Janet

    2016-04-01

    DNA-sequencing giant Illumina has formed a new company, called Grail, to develop liquid biopsies capable of spotting cancer before symptoms arise. The start-up is working on a low-cost "pan-cancer" test that can detect multiple cancer types early, which it hopes to introduce by 2019.

  16. Reflecting on Early Literacy Development in the Context of Vanuatu

    Science.gov (United States)

    Hughes, Desma

    2004-01-01

    A low level of literacy development plagues many parts of the Pacific region despite the fact that parents are very keen for their children to become literate in order to embrace the modern world. Issues concerning early education and the attainment of literacy are still a challenge in the Pacific. In order to understand the reasons for the low…

  17. Early retinoic acid deprivation in developing zebrafish results in microphthalmia.

    Science.gov (United States)

    Le, Hong-Gam T; Dowling, John E; Cameron, D Joshua

    2012-09-01

    Vitamin A deficiency causes impaired vision and blindness in millions of children around the world. Previous studies in zebrafish have demonstrated that retinoic acid (RA), the acid form of vitamin A, plays a vital role in early eye development. The objective of this study was to describe the effects of early RA deficiency by treating zebrafish with diethylaminobenzaldehyde (DEAB), a potent inhibitor of the enzyme retinaldehyde dehydrogenase (RALDH) that converts retinal to RA. Zebrafish embryos were treated for 2 h beginning at 9 h postfertilization. Gross morphology and retinal development were examined at regular intervals for 5 days after treatment. The optokinetic reflex (OKR) test, visual background adaptation (VBA) test, and the electroretinogram (ERG) were performed to assess visual function and behavior. Early treatment of zebrafish embryos with 100 μM DEAB (9 h) resulted in reduced eye size, and this microphthalmia persisted through larval development. Retinal histology revealed that DEAB eyes had significant developmental abnormalities but had relatively normal retinal lamination by 5.5 days postfertilization. However, the fish showed neither an OKR nor a VBA response. Further, the retina did not respond to light as measured by the ERG. We conclude that early deficiency of RA during eye development causes microphthalmia as well as other visual defects, and that timing of the RA deficiency is critical to the developmental outcome.

  18. Predictors of Early versus Later Spelling Development in Danish

    Science.gov (United States)

    Nielsen, Anne-Mette Veber; Juul, Holger

    2016-01-01

    The present study examined phoneme awareness, phonological short term memory, letter knowledge, rapid automatized naming (RAN), and visual-verbal paired associate learning (PAL) as longitudinal predictors of spelling skills in an early phase (Grade 2) and a later phase (Grade 5) of development in a sample of 140 children learning to spell in the…

  19. Early development of synchrony in cortical activations in the human.

    Science.gov (United States)

    Koolen, N; Dereymaeker, A; Räsänen, O; Jansen, K; Vervisch, J; Matic, V; Naulaers, G; De Vos, M; Van Huffel, S; Vanhatalo, S

    2016-05-13

    Early intermittent cortical activity is thought to play a crucial role in the growth of neuronal network development, and large scale brain networks are known to provide the basis for higher brain functions. Yet, the early development of the large scale synchrony in cortical activations is unknown. Here, we tested the hypothesis that the early intermittent cortical activations seen in the human scalp EEG show a clear developmental course during the last trimester of pregnancy, the period of intensive growth of cortico-cortical connections. We recorded scalp EEG from altogether 22 premature infants at post-menstrual age between 30 and 44 weeks, and the early cortical synchrony was quantified using recently introduced activation synchrony index (ASI). The developmental correlations of ASI were computed for individual EEG signals as well as anatomically and mathematically defined spatial subgroups. We report two main findings. First, we observed a robust and statistically significant increase in ASI in all cortical areas. Second, there were significant spatial gradients in the synchrony in fronto-occipital and left-to-right directions. These findings provide evidence that early cortical activity is increasingly synchronized across the neocortex. The ASI-based metrics introduced in our work allow direct translational comparison to in vivo animal models, as well as hold promise for implementation as a functional developmental biomarker in future research on human neonates.

  20. Seed Germination and Seedling Survival of Spartina alterniflora Loisel

    Directory of Open Access Journals (Sweden)

    Patrick D. Biber

    2008-01-01

    Full Text Available Spartina alterniflora (smooth cordgrass is a widespread intertidal salt marsh plant that is frequently used in coastal restoration projects. Seeds collected in 2004 were tested for seed germination and seedling survival after 6 months of cold seed storage to determine differences among collection locations (experiment 1. Seeds collected in 2005, after Hurricane Katrina, were tested for seed germination and seedling survival from 0 to 15 months of cold seed storage time to determine minimum and maximum storage time and seedling survival rates (experiment 2. Seed germination increased from 1-4 months of cold, wet storage (stratification and then began to decline. Survival of the seedlings was highest after 2 months of stratification. In experiment 1, seedling size was found to vary widely among seedlings of the same source and age. Seedling height at 22 days after planting ranged from 2-16 cm, despite identical environmental conditions. Selective breeding could target plants with fast early growth characteristics to promote strains that can be raised quickly in a nursery in response to demands for restoration.

  1. Early life environment and the developing cardiovascular system

    OpenAIRE

    Idris, N.S.

    2015-01-01

    Background The dynamics of cardiovascular system development in childhood are still largely unknown. Despite its known sensitivity to small perturbations, it has not been fully elucidated how the cardiovascular system evolves and responds to different stimuli and how these impact the future cardiovascular status. This thesis is basically aimed at exploring the effects of several possible postnatal determinantson the developing cardiovascular system. These early life determinants perhaps immed...

  2. Zebrafish in the Study of Early Cardiac Development

    OpenAIRE

    Liu, Jiandong; Stainier, Didier Y.R.

    2012-01-01

    Heart development is a complex process that involves cell specification and differentiation, as well as elaborate tissue morphogenesis and remodeling, to generate a functional organ. The zebrafish has emerged as a powerful model system to unravel the basic genetic, molecular and cellular mechanisms of cardiac development and function. Here we summarize and discuss recent discoveries on early cardiac specification and the identification of the second heart field in zebrafish. In addition to th...

  3. Altered anterior visual system development following early monocular enucleation

    Directory of Open Access Journals (Sweden)

    Krista R. Kelly

    2014-01-01

    Conclusions: The novel finding of an asymmetry in morphology of the anterior visual system following long-term survival from early monocular enucleation indicates altered postnatal visual development. Possible mechanisms behind this altered development include recruitment of deafferented cells by crossing nasal fibres and/or geniculate cell retention via feedback from primary visual cortex. These data highlight the importance of balanced binocular input during postnatal maturation for typical anterior visual system morphology.

  4. Does copepods influence dusky grouper (Epinephelus marginatus early development?

    Directory of Open Access Journals (Sweden)

    Monica Mateus

    2014-06-01

    Full Text Available Good knowledge on the development of early life stages is essential for successful conservation programs of threatened fish species. Diet and rearing system affects early life survival and juvenile quality. Copepods are the natural food of fish larvae in the wild possessing high nutritional value, when compared with live feeds used in aquaculture (rotifers and artemia, and a wide range of size classes. Rearing systems with low water column disturbance and low larval densities enhanced the survival of fragile fish larvae. The aim of this work is to evaluate the effect of the introduction of copepods in the diet of early dusky grouper larvae reared in controlled mesocosm systems using larval development and juvenile quality as indicators. Two feeding protocols were tested, one composed only by rotifers (Brachionus plicatilis, brine shrimp (Artemia spp. and dry feed and the other supplemented with copepods (Paracartia grani from mouth opening (2 day after hatching - DAH to 8 DAH. Feeding behavior, growth, survival, skeletal malformations and digestive enzymes activity was assessed at different developmental stages. The addition of copepods to the early larvae diet of dusky grouper resulted in faster development and higher survival rates. Larvae fed with copepods improved their development. At 20 DAH all larvae reared at the mesocosm with copedods were already at the stage of post-flexion while in the system without copepods this stage was attained later. At 25 DAH only 64% of the larvae were in post flexion in the mesoscosm without copepods. At 30 DAH larvae supplemented with copepods attained an acidic digestion (high specific activity of pepsin earlier than at the system without copepods. In this last system alkaline digestion (trypsin specific activity, characteristic of early larval stages, was significantly higher reinforcing the faster development of larvae fed with copepods. In both systems the incidence of skeletal malformations was low.

  5. Evolutionary origins and early development of number processing

    CERN Document Server

    Geary, David C; Mann Koepke, Kathleen

    2014-01-01

    The first volume in this ground-breaking series focuses on the origins and early development of numerical cognition in non-human primates, lower vertebrates, human infants, and preschool children. The text will help readers understand the nature and complexity of these foundational quantitative concepts and skills along with evolutionary precursors and early developmental trajectories. Brings together and focuses the efforts and research of multiple disciplines working in math cognition.The contributors bring vast knowledge and experience to bear on resolving extant

  6. Chemical-Induced Inhibition of Blue Light-Mediated Seedling Development Caused by Disruption of Upstream Signal Transduction Involving Cryptochromes in Arabidopsis thaliana.

    Science.gov (United States)

    Ong, Wen-Dee; Okubo-Kurihara, Emiko; Kurihara, Yukio; Shimada, Setsuko; Makita, Yuko; Kawashima, Mika; Honda, Kaori; Kondoh, Yasumitsu; Watanabe, Nobumoto; Osada, Hiroyuki; Cutler, Sean R; Sudesh, Kumar; Matsui, Minami

    2017-01-01

    Plants have a remarkable ability to perceive and respond to various wavelengths of light and initiate regulation of different cascades of light signaling and molecular components. While the perception of red light and the mechanisms of its signaling involving phytochromes are largely known, knowledge of the mechanisms of blue light signaling is still limited. Chemical genetics involves the use of diverse small active or synthetic molecules to evaluate biological processes. By combining chemicals and analyzing the effects they have on plant morphology, we identified a chemical, 3-bromo-7-nitroindazole (3B7N), that promotes hypocotyl elongation of wild-type Arabidopsis only under continuous blue light. Further evaluation with loss-of-function mutants confirmed that 3B7N inhibits photomorphogenesis through cryptochrome-mediated light signaling. Microarray analysis demonstrated that the effect of 3B7N treatment on gene expression in cry1cry2 is considerably smaller than that in the wild type, indicating that 3B7N specifically interrupts cryptochrome function in the control of seedling development in a light-dependent manner. We demonstrated that 3B7N directly binds to CRY1 protein using an in vitro binding assay. These results suggest that 3B7N is a novel chemical that directly inhibits plant cryptochrome function by physical binding. The application of 3B7N can be used on other plants to study further the blue light mechanism and the genetic control of cryptochromes in the growth and development of plant species. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. Water-Soluble Lignins from Different Bioenergy Crops Stimulate the Early Development of Maize (Zea mays, L.).

    Science.gov (United States)

    Savy, Davide; Cozzolino, Vincenza; Vinci, Giovanni; Nebbioso, Antonio; Piccolo, Alessandro

    2015-11-05

    The molecular composition of water-soluble lignins isolated from four non-food bioenergy crops (cardoon CAR, eucalyptus EUC, and two black poplars RIP and LIM) was characterized in detail, and their potential bioactivity towards maize germination and early growth evaluated. Lignins were found to not affect seed germination rates, but stimulated the maize seedling development, though to a different extent. RIP promoted root elongation, while CAR only stimulated the length of lateral seminal roots and coleoptile, and LIM improved only the coleoptile development. The most significant bioactivity of CAR was related to its large content of aliphatic OH groups, C-O carbons and lowest hydrophobicity, as assessed by (31)P-NMR and (13)C-CPMAS-NMR spectroscopies. Less bioactive RIP and LIM lignins were similar in composition, but their stimulation of maize seedling was different. This was accounted to their diverse content of aliphatic OH groups and S- and G-type molecules. The poorest bioactivity of the EUC lignin was attributed to its smallest content of aliphatic OH groups and largest hydrophobicity. Both these features may be conducive of a EUC conformational structure tight enough to prevent its alteration by organic acids exuded from vegetal tissues. Conversely the more labile conformational arrangements of the other more hydrophilic lignin extracts promoted their bioactivity by releasing biologically active molecules upon the action of exuded organic acids. Our findings indicate that water-soluble lignins from non-food crops may be effectively used as plant biostimulants, thus contributing to increase the economic and ecological liability of bio-based industries.

  8. Early vocabulary development in children with bilateral cochlear implants.

    Science.gov (United States)

    Välimaa, Taina; Kunnari, Sari; Laukkanen-Nevala, Päivi; Lonka, Eila

    2017-06-16

    Children with unilateral cochlear implants (CIs) may have delayed vocabulary development for an extended period after implantation. Bilateral cochlear implantation is reported to be associated with improved sound localization and enhanced speech perception in noise. This study proposed that bilateral implantation might also promote early vocabulary development. Knowledge regarding vocabulary growth and composition in children with bilateral CIs and factors associated with it may lead to improvements in the content of early speech and language intervention and family counselling. To analyse the growth of early vocabulary and its composition during the first year after CI activation and to investigate factors associated with vocabulary growth. The participants were 20 children with bilateral CIs (12 boys; eight girls; mean age at CI activation = 12.9 months). Vocabulary size was assessed with the Finnish version of the MacArthur Communicative Development Inventories (CDI) Infant Form and compared with normative data. Vocabulary composition was analysed in relation to vocabulary size. Growth curve modelling was implemented using a linear mixed model to analyse the effects of the following variables on early vocabulary growth: time, gender, maternal education, residual hearing with hearing aids, age at first hearing aid fitting and age at CI activation. Despite clear vocabulary growth over time, children with bilateral CIs lagged behind their age norms in receptive vocabulary during the first 12 months after CI activation. In expressive vocabulary, 35% of the children were able to catch up with their age norms, but 55% of the children lagged behind them. In receptive and expressive vocabularies of 1-20 words, analysis of different semantic categories indicated that social terms constituted the highest proportion. Nouns constituted the highest proportion in vocabularies of 101-400 words. The proportion of verbs remained below 20% and the proportion of function words and

  9. An Idea (Like a Seedling) Grows. Genesis and Development of Outdoor/Conservation Education in Bloomfield Hills, Michigan.

    Science.gov (United States)

    Hollums, Don

    The document describes how outdoor education in the Bloomfield Hills School District of Michigan can be traced to 1957, when elementary school students participated in a resident outdoor school experience for a week. In 1968, a committee on outdoor education was formally organized. The committee developed a rationale and objectives for outdoor…

  10. Development of Early Warning Methods for Electric Power Systems

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur

    This thesis concerns the development of methods that can provide, in realtime, an early warning for an emerging blackout in electric power systems. The blackout in E-Denmark and S-Sweden on September 23, 2003 is the main motivation for the method development. The blackout was caused by occurrence...... methods, that could, in such situations, give an early warning for the emerging blackout. After investigation of data and plots taken from the time of the blackout, it was decided to focus the development on assessment of aperiodic small signal stability. In order to assess the system generators aperiodic...... small signal stability, expressions for stability boundaries were algebraically derived in the injection impedance plane. A method for detecting aperiodic small signal stability was established, which was based on one of the derived boundaries. The method carries out an element-wise assessment...

  11. Early childhood WIC participation, cognitive development and academic achievement.

    Science.gov (United States)

    Jackson, Margot I

    2015-02-01

    For the 22% of American children who live below the federal poverty line, and the additional 23% who live below twice that level, nutritional policy is part of the safety net against hunger and its negative effects on children's development. The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) provides steadily available food from the food groups essential for physical and cognitive development. The effects of WIC on dietary quality among participating women and children are strong and positive. Furthermore, there is a strong influence of nutrition on cognitive development and socioeconomic inequality. Yet, research on the non-health effects of U.S. child nutritional policy is scarce, despite the ultimate goal of health policies directed at children-to enable productive functioning across multiple social institutions over the life course. Using two nationally representative, longitudinal surveys of children-the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B) and the Child Development Supplement (CDS) of the Panel Study of Income Dynamics-I examine how prenatal and early childhood exposure to WIC is associated in the short-term with cognitive development, and in the longer-term with reading and math learning. Results show that early WIC participation is associated with both cognitive and academic benefits. These findings suggest that WIC meaningfully contributes to children's educational prospects.

  12. Effect of Different Basta Dosage on Seedling Quality and Yield of Herbicide-resistant Early Rice%不同草铵膦用量对耐除草剂水稻秧苗素质及产量的影响

    Institute of Scientific and Technical Information of China (English)

    杨益善; 唐俐; 蔡卫青; 邓晓湘; 盛夏冰

    2012-01-01

    以含Bar基因的耐除草剂水稻品种和不耐除草剂的水稻不育系为材料,幼苗期喷施不同用量草铵膦,研究了草铵膦对不耐除草剂水稻幼苗的致死剂量以及不同草铵膦用量对耐除草剂水稻生长发育的影响.结果表明:草铵膦对不耐除草剂的不育系的软盘育秧致死剂量≤15mg/m2、厢面湿润育秧致死剂量≤30mg/m2;在幼苗期喷施一定剂量的草铵膦(15 mg/m2~75 mg/m2)对耐除草剂水稻秧苗会产生不同程度的伤害作用,秧苗素质不同程度下降;喷施草铵膦45 mg/m2~75mg/m2后的秧苗移栽大田后,生长发育有所延迟,但产量没有受到显著影响.%The lethal dose of basta to young seedlings of herbicide-susceptive rice and the effect of basta dosage on the growth and development of herbicide-resistant rice were studied by spraying different basta dosage at seedling stage with herbicide-resistant rice containing Bar gene and herbicide-susceptive rice male sterile (MS) lines as materials. The results showed that the lethal dose of basta to young seedlings of herbicide-susceptive rice MS lines was ≤ 15mg/m2 when raised in the trays, and ≤ 30mg/m2 when raised in the wet seedling bed. The seedlings of herbicide-resistant rice were damaged to some extent with seedling quality decreased in some different degree when treated by different dosage of basta with 15 mg/m2~75 mg/m2 at seedling stage. The growth and development of the seedlings of herbicide-resistant rice treated by basta with the dosage of 45mg/m2~75 mg/m2 were delayed to some extent after transplanting, but the grain yield was not effected significantly.

  13. Strong microsite control of seedling recruitment in tundra

    DEFF Research Database (Denmark)

    Graae, Bente J; Ejrnæs, Rasmus; Lang, Simone I

    2011-01-01

    , the experimental seed addition showed that the microsite environment was even more important. For all species, seedling emergence peaked at the productive end of the gradient, irrespective of the adult niches realized. Disturbance promoted recruitment at all positions along the environmental gradient, not just......The inclusion of environmental variation in studies of recruitment is a prerequisite for realistic predictions of the responses of vegetation to a changing environment. We investigated how seedling recruitment is affected by seed availability and microsite quality along a steep environmental...... at high productivity. Early seedling emergence constituted the main temporal bottleneck in recruitment for all species. Surprisingly, winter mortality was highest at what appeared to be the most benign end of the gradient. The results highlight that seedling recruitment patterns are largely determined...

  14. Efeito da qualidade das sementes sobre a formação de mudas de alface Effect of seed quality on lettuce seedlings development

    Directory of Open Access Journals (Sweden)

    Simone M. Franzin

    2005-06-01

    Full Text Available Determinou-se o efeito da qualidade fisiológica das sementes sobre a formação de mudas de alface. Utilizaram-se dois lotes de sementes com diferentes níveis de qualidade inicial, das cultivares Regina e Vera, selecionados por meio dos testes de germinação, primeira contagem, envelhecimento acelerado, condutividade elétrica e emergência em "gerbox". Os efeitos dos níveis de qualidade sobre a produção de mudas foram avaliados por meio dos testes de índice de velocidade de emergência, número de folhas, altura da parte aérea, comprimento de raízes, massa úmida e seca das mudas e classificação do vigor das mudas. Utilizou-se o delineamento inteiramente casualizado, com os dados analisados pelo teste Tukey em 5% de probabilidade. Houve efeito favorável na qualidade das sementes das cultivares Regina e Vera para a formação de mudas aos 20 dias após a semeadura. Concluiu-se que sementes de alta qualidade fisiológica produzem maior percentagem de mudas vigorosas, com maior número de folhas, maior altura da parte aérea e comprimento de raízes e maior massa aos 20 dias de cultivo.The effect of the physiological quality of the seeds on lettuce seedlings was established. Two lots of lettuce seeds cv. Regina and Vera with different levels of initial quality were used. These lots were selected based upon germination tests: first score, fast aging, electrical conductivity and emergence in gerbox. The effects of the quality levels on the seedling production were evaluated through the parameters: speed rate emergence tests, number of leaves, height of the aerial part, root length, dry and wet mass of the seedlings and classification of the vitality of the seedlings. The experiment was carried out in a completely randomized design with four replications. Seed quality of the cultivars Regina and Vera have a positive effect on the formation of seedlings 20 days after sowing. High physiological quality seeds produce a higher percentage of

  15. [Dental caries and early childhood development: a pilot study].

    Science.gov (United States)

    Núñez, F Loreto; Sanz, B Javier; Mejía, L Gloria

    2015-01-01

    To investigate the association between dental caries and early childhood development in 3-year-olds from Talca, Chile. A pilot study with a convenience sample of 3-year-olds from Talca (n = 39) who attend public healthcare centers. Child development was measured by the Psychomotor Development Index (PDI), a screening tool used nationally among pre-school children to assess language development, fine motor skills and coordination areas. Dental caries prevalence was evaluated by decayed, missing, filled teeth (DFMT) and decayed, missing, filled tooth surfaces (DFMS) ceo-d and ceo-s indexes. The children were divided into two groups according to the PDIscore: those with a score of 40 or more were considered developmentally normal (n = 32), and those with a score below 40 were considered as having impaired development (n = 7). The severity of caries (DMFT) was negatively correlated with PDI (r = -0.82), and children with the lowest TEPSI score had the highest DFMT values. The average DMFT in children with normal development was 1.31, and 3.57 for those with impaired development. This pilot study indicates that the severity of dental caries is correlated with early childhood development. Copyright © 2015. Publicado por Elsevier España, S.L.U.

  16. Early Bifrontal Brain Injury: Disturbances in Cognitive Function Development

    Directory of Open Access Journals (Sweden)

    Christine Bonnier

    2010-01-01

    Full Text Available We describe six psychomotor, language, and neuropsychological sequential developmental evaluations in a boy who sustained a severe bifrontal traumatic brain injury (TBI at 19 months of age. Visuospatial, drawing, and writing skills failed to develop normally. Gradually increasing difficulties were noted in language leading to reading and spontaneous speech difficulties. The last two evaluations showed executive deficits in inhibition, flexibility, and working memory. Those executive abnormalities seemed to be involved in the other impairments. In conclusion, early frontal brain injury disorganizes the development of cognitive functions, and interactions exist between executive function and other cognitive functions during development.

  17. Conditions on Early Mars Might Have Fostered Rapid and Early Development of Life

    Science.gov (United States)

    Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

    2007-01-01

    The exploration of Mars during the past decades has begun to unveil the history of the planet. The combinations of remote sensing, in situ geochemical compositional measurements and photographic observations from both above and on the surface have shown Mars to have a dynamic and active geologic evolution. Mars geologic evolution clearly had conditions that were suitable for supporting life. For a planet to be able to be habitable, it must have water, carbon sources, energy sources and a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water-carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001 well-dated at approx.3.9 Gy., (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, early active volcanism continuing throughout Martian history, and, and continuing impact processes, (iii) Carbon and water from possibly extensive volcanic outgassing (i.e. H2O, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) some crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust. The question arises: "Why would life not evolve from these favorable conditions on early Mars in its first 600 My?" During this period, it seems likely that environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would all favor the formation of early life. Even if life developed elsewhere (on Earth, Venus, or on other solar systems) and was transported to Mars, the surface conditions were likely very hospitable for that introduced life to multiply and evolve.

  18. Priorities for early childhood development in low-income countries.

    Science.gov (United States)

    Olusanya, Bolajoko O

    2011-01-01

    The remarkable progress in reducing child mortality in low-income countries is now accompanied with a rapidly expanding population of child survivors and increased life expectancy. However, many have special health care needs in the early foundational years for optimal health and educational and vocational status. Investment in early childhood development (ECD) is therefore crucial but likely to be constrained by lack of adequate resources making priority-setting inevitable. A review of current ECD approaches in sub-Saharan Africa and South Asia shows that concerted multidisciplinary and cross-sectoral initiatives targeted at children with developmental disabilities across all crucial domains of ECD and guided by available evidence on optimal timing for interventions are urgently required. This focus would necessitate appropriate national ECD policies, modifications to the current global ECD programs in the developing world, and a more active collaboration between pediatricians and other related service providers.

  19. EARLY DEVELOPMENT OF SPEECH AND INTERACTION BETWEEN MOTHER AND CHILD

    OpenAIRE

    Ana RADOJKOVIC; Slavica GOLUBOVIC; Dejan RADOJKOVIC

    1998-01-01

    Respecting the opinions of the modern researches which show that early interaction between mother and child has the crucial importance in child’s development, almost in all parts of child’s functions (speech, emotions, motor functions, intelligence). The authors did their own research that does not diffuse from the result got from former researches.Although this research is related to normal population of the children, also it is very important for speech in context of interaction between mot...

  20. Gravity from strings: personal reminiscence on early developments

    CERN Document Server

    Yoneya, Tamiaki

    2009-01-01

    I discuss the early developments of string theory with respect to its connection with gauge theory and general relativity from my own perspective. The period covered is mainly from 1969 to 1974, during which I became involved in research on dual string models as a graduate student. My thinking towards the recognition of string theory as an extended quantum theory of gravity is described. Some retrospective remarks on my later works related to this subject are also given.

  1. Dynamic Self-Organization and Early Lexical Development in Children

    Science.gov (United States)

    Li, Ping; Zhao, Xiaowei; Whinney, Brian Mac

    2007-01-01

    In this study we present a self-organizing connectionist model of early lexical development. We call this model DevLex-II, based on the earlier DevLex model. DevLex-II can simulate a variety of empirical patterns in children's acquisition of words. These include a clear vocabulary spurt, effects of word frequency and length on age of acquisition,…

  2. Early embryonic development and transplantation in tree shrews

    OpenAIRE

    YAN, Lan-Zhen; Sun, Bin; LYU, Long-Bao; MA, Yu-Hua; Chen, Jia-Qi; Lin, Qing; Zheng, Ping; Zhao, Xu-dong

    2016-01-01

    As a novel experimental animal model, tree shrews have received increasing attention in recent years. Despite this, little is known in regards to the time phases of their embryonic development. In this study, surveillance systems were used to record the behavior and timing of copulations; embryos at different post-copulation stages were collected and cultured in vitro; and the developmental characteristics of both early-stage and in vitro cultured embryos were determined. A total of 163 femal...

  3. Progress Developing the Kansas Early Childhood Special Education Accountability System: Initial Findings Using ECO and COSF

    Science.gov (United States)

    Greenwood, Charles R.; Walker, Dale; Hornbeck, Marguerite; Hebbeler, Kathleen; Spiker, Donna

    2007-01-01

    Policy decision makers, early educators, and early interventionists face numerous challenges as they develop and implement statewide accountability systems to evaluate and improve children's early intervention and early childhood special education outcomes. Kansas was an early adopter of the Child Outcomes Summary Form (COSF) developed by the…

  4. Characterization of rhizobacteria associated with weed seedlings.

    Science.gov (United States)

    Kremer, R J; Begonia, M F; Stanley, L; Lanham, E T

    1990-06-01

    Rhizobacteria were isolated from seedlings of seven economically important weeds and characterized for potential phytopathogenicity, effects on seedling growth, and antibiosis to assess the possibility of developing deleterious rhizobacteria as biological control agents. The abundance and composition of rhizobacteria varied among the different weed species. For example, fluorescent pseudomonads represented from 11 to 42% of the total rhizobacterial populations from jimsonweed and lambsquarters, respectively. Other bacteria frequently isolated were nonfluorescent pseudomonads, Erwinia herbicola, Alcaligenes spp., and Flavobacterium spp. Only 18% of all isolates were potentially phytopathogenic, based on an Escherichia coli indicator bioassay. However, the proportion of isolates that inhibited growth in seedling assays ranged from 35 to 65% depending on the weed host. Antibiosis was most prevalent among isolates of fluorescent Pseudomonas spp., the activity of which was due to siderophore production in over 75% of these isolates. Overall, rhizobacterial isolates exhibited a complex array of properties that were inconsistent with accepted definitions for plant growth-promoting and deleterious rhizobacteria. It is suggested that for development of effective biological control agents for weed control, deleterious rhizobacteria must be screened directly on host seedlings and must possess several properties including high colonizing ability, specific phytotoxin production, and resistance or tolerance to antibiotics produced by other rhizosphere microorganisms, and they must either synthesize or utilize other bacterial siderophores.

  5. Hormonal control of endoreduplication in sugar beet (Beta vulgaris L.) seedlings growing in vitro.

    Science.gov (United States)

    Lukaszewska, E; Virden, R; Sliwinska, E

    2012-01-01

    The effect on endoreduplication in sugar beet (Beta vulgaris L.) seedlings of five plant hormones in MS medium, ethylene, 24-epibrassinolide (EBR), gibberellic acid (GA(3) ), kinetin and 1-naphthaleneacetic acid (NAA), as well as a combination of kinetin and NAA at two different concentrations, was studied using flow cytometry. Analyses of DNA content in nuclei of the root, hypocotyl and cotyledons of seedlings growing in vitro were performed during their early development, starting from when the root was 0.5-1.0 cm long until expansion of the first pair of leaves. The proportions of nuclei with different DNA contents were established and the mean C-value calculated. The presence of exogenous plant hormones changed endoreduplication intensity, although to different extents, depending on the organ and developmental stage. Ethylene and NAA stimulated the process, while EBR and kinetin suppressed it and GA did not clearly affect it.

  6. Development of tsunami early warning systems and future challenges

    Directory of Open Access Journals (Sweden)

    J. Wächter

    2012-06-01

    Full Text Available Fostered by and embedded in the general development of information and communications technology (ICT, the evolution of tsunami warning systems (TWS shows a significant development from seismic-centred to multi-sensor system architectures using additional sensors (e.g. tide gauges and buoys for the detection of tsunami waves in the ocean.

    Currently, the beginning implementation of regional tsunami warning infrastructures indicates a new phase in the development of TWS. A new generation of TWS should not only be able to realise multi-sensor monitoring for tsunami detection. Moreover, these systems have to be capable to form a collaborative communication infrastructure of distributed tsunami warning systems in order to implement regional, ocean-wide monitoring and warning strategies.

    In the context of the development of the German Indonesian Tsunami Early Warning System (GITEWS and in the EU-funded FP6 project Distant Early Warning System (DEWS, a service platform for both sensor integration and warning dissemination has been newly developed and demonstrated. In particular, standards of the Open Geospatial Consortium (OGC and the Organization for the Advancement of Structured Information Standards (OASIS have been successfully incorporated.

    In the FP7 project Collaborative, Complex and Critical Decision-Support in Evolving Crises (TRIDEC, new developments in ICT (e.g. complex event processing (CEP and event-driven architecture (EDA are used to extend the existing platform to realise a component-based technology framework for building distributed tsunami warning systems.

  7. Sonic hedgehog expression during early tooth development in Suncus murinus.

    Science.gov (United States)

    Miyado, Mami; Ogi, Hidenao; Yamada, Gen; Kitoh, Junzo; Jogahara, Takamichi; Oda, Sen-Ichi; Sato, Iwao; Miyado, Kenji; Sunohara, Masataka

    2007-11-16

    Tooth development is a highly organized process characterized by reciprocal interactions between epithelium and mesenchyme. However, the expression patterns and functions of molecules involved in mouse tooth development are unclear from the viewpoint of explaining human dental malformations and anomalies. Here, we show the expression of sonic hedgehog (Shh), a potent initiator of morphogenesis, during the early stages of tooth development in Suncus murinus. Initially, symmetrical, elongated expression of suncus Shh (sShh) was observed in the thin layer of dental epithelial cells along the mesial-distal axis of both jaws. As the dental epithelium continued to develop, sShh was strictly restricted to the predicted leading parts of the growing, invaginating epithelium corresponding to tooth primordia and enamel knots. We propose that some aspects of Shh function in tooth development are widely conserved in mammalian phylogeny.

  8. Substrate in the emergence and initial growth of seedlings of Caesalpinia pulcherrima

    Directory of Open Access Journals (Sweden)

    Magnólia Martins Alves

    Full Text Available ABSTRACT: Caesalpinia pulcherrima is an exotic species belongs to the Fabaceae family commonly known as flamboyant-mirim, and widely used for urban forestry. This study aimed to evaluate the effect of different substrates on the emergence and early seedlings growth of C. pulcherrima . The experiment was conducted in a greenhouse belonging to the Centro de Ciências Agrárias, Universidade Federal da Paraíba. The experimental design was completely randomized and treatments had 14 substrates: sand, vegetable soil, vermiculite, wood dust, carbonized rice straw, vegetable soil + sand 1:1, sand + wood dust 1:1, sand + carbonized rice straw 1:1, earth + wood dust 1:1, vegetable soil + carbonized rice straw 1:1, vermiculite + sand 1:1, vermiculite + wood dust 1:1, vermiculite + earth 1:1 and vermiculite + carbonized rice straw 1:1. Evaluation of the effect of the treatments was through the following determinations: percentage of emergency, first count, index of germination speed, length and dry weight of roots and shoots. The vermiculite, vegetable soil + sand 1:1, vermiculite + sand 1:1, vermiculite + saw dust 1:1, are suitable for emergence and early growth of seedlings of Caesalpinia pulcherrima . Substrates saw dust and carbonized rice straw were responsible for the worst performers on emergence and seedling development.

  9. Development of an assisting detection system for early infarct diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Sim, K. S.; Nia, M. E.; Ee, C. S. [Faculty of Engineering and Technology, Multimedia University, Melaka (Malaysia)

    2015-04-24

    In this paper, a detection assisting system for early infarct detection is developed. This new developed method is used to assist the medical practitioners to diagnose infarct from computed tomography images of brain. Using this assisting system, the infarct could be diagnosed at earlier stages. The non-contrast computed tomography (NCCT) brain images are the data set used for this system. Detection module extracts the pixel data from NCCT brain images, and produces the colourized version of images. The proposed method showed great potential in detecting infarct, and helps medical practitioners to make earlier and better diagnoses.

  10. Effects of topsoil removal on seedling emergence and species diversity

    Energy Technology Data Exchange (ETDEWEB)

    Winkel, V.K.; Ostler, W.K.

    1994-02-01

    Approximately 800 hectares on the US Department of Energy Nevada Test Site and vicinity are contaminated with Plutonium. As part of a cleanup effort, both the vegetation and the top 5--10 cm of soil may be removed. A study was developed to determine the effects of topsoil removal on seedling emergence and plant species diversity. Trial plots were prepared by removing 5, 10, or 20 cm of topsoil, seeding a mix of nine native species, mulching with straw, and then anchoring the straw with erosion netting. Additional plots (0 topsoil removal treatment) were lightly bladed to remove existing vegetation and then treated as above. Approximately 85 mm of supplemental irrigation was applied to help initiate germination during early spring. Seedling density data of seeded and nonseeded species was collected following emergence, and species diversity was calculated with the Shannon diversity index for the nonseeded species. Densities of seeded species either were unaffected by or increased with increased depth of topsoil removal. In general, densities of nonseeded species decreased with increased depth of topsoil removal. The number of species, species diversity and evenness also decreased with increased depth of topsoil removal. Initial emergence of seeded species is apparently unaffected by topsoil removal at this site.

  11. Identification of early salt-stress responsive proteins in seedling roots of upland cotton (Gossypium hirsutum L. employing iTRAQ-based proteomic technique

    Directory of Open Access Journals (Sweden)

    Wu eLi

    2015-09-01

    Full Text Available Soil salinity is a major abiotic stress that limits plant growth and agricultural productivity. Upland cotton (Gossypium hirsutum L. is highly tolerant to salinity; however, large-scale proteomic data of cotton in response to salt-stress are still scanty. Here, an iTRAQ-based proteomic technique was employed to identify the early differentially expressed proteins (DEPs from salt-treated cotton roots. 77 up-regulated and 52 down-regulated proteins were identified. The majority of the proteins have functions related to carbohydrate and energy metabolism, transcription related, protein metabolism, cell wall and cytoskeleton metabolism, membrane and transport, signal transduction, as well as stress and defense. It is worth emphasizing that some novel salt-responsive proteins were identified, which involved in cell cytoskeleton metabolism(ARP2 and FLAs), membrane transport(TIPs and PIPs), signal transduction(LRR-RLKs)and stress responses(TLP, USP, DIR,desiccation-related protein PCC13-62. High positive correlation was evaluated between the abundance of some altered proteins (SOD, POD, GST, MDAR and MDH and their enzyme activity. The results demonstrate the iTRAQ-based proteomic technique is reliable for identifying and quantifying a large number of cotton root proteins. qRT-PCR was used to study the gene expression levels of five above-mentioned proteins, four patterns are consistent with those of induced protein. These results showed that cotton’s proteome to NaCl stress is complex, and that the comparative protein profiles of roots under salinity vs control improve the understanding of the molecular mechanisms involved in the tolerance of plants to salt stress. It provides a good starting point for further functional elucidation of these DEPs using genetic and/or other approaches, and thereby candidate genes for genetic engineering to improve crop salt tolerance.

  12. Improving seedling growth in longleaf pine plantations with nematicidal soil fumigants.

    Science.gov (United States)

    Ruehle, J L

    1969-07-01

    In-row, preplanting fumigation with DD and DBCP in a longleaf pine plantation was evaluated for nematode control, improved seedling survival, and early and uniform release of seedlings from the grass stage. Only DD significantly lowered the nematode population during the first growing season. DBCP not only failed to control nematodes, but was phytotoxic. Fumigation had little effect on seedling survival. Seedlings in rows fumigated with DD started height growth earlier and produced taller trees after 5 years than those in nonfumigated rows.

  13. Gestural development and its relation to a child's early vocabulary.

    Science.gov (United States)

    Kraljević, Jelena Kuvač; Cepanec, Maja; Simleša, Sanja

    2014-05-01

    Gesture and language are tightly connected during the development of a child's communication skills. Gestures mostly precede and define the way of language development; even opposite direction has been found. Few recent studies have focused on the relationship between specific gestures and specific word categories, emphasising that the onset of one gesture type predicts the onset of certain word categories or of the earliest word combinations. The aim of this study was to analyse predicative roles of different gesture types on the onset of first word categories in a child's early expressive vocabulary. Our data show that different types of gestures predict different types of word production. Object gestures predict open-class words from the age of 13 months, and gestural routines predict closed-class words and social terms from 8 months. Receptive vocabulary has a strong mediating role for all linguistically defined categories (open- and closed-class words) but not for social terms, which are the largest word category in a child's early expressive vocabulary. Accordingly, main contribution of this study is to define the impact of different gesture types on early expressive vocabulary and to determine the role of receptive vocabulary in gesture-expressive vocabulary relation in the Croatian language. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Clinical assessment of early language development: a simplified short form of the Mandarin communicative development inventory.

    Science.gov (United States)

    Soli, Sigfrid D; Zheng, Yun; Meng, Zhaoli; Li, Gang

    2012-09-01

    The purpose of this study was to develop a practical mean for clinical evaluation of early pediatric language development by establishing developmental trajectories for receptive and expressive vocabulary growth in children between 6 and 32 months of age using a simple, time-efficient assessment tool. Simplified short form versions of the Words and Gestures and Words and Sentences vocabulary inventories in the Mandarin Communicative Development Inventory [1] were developed and used to assess early language development in developmentally normal children from 6 to 32 months of age during routine health checks. Developmental trajectories characterizing the rate of receptive and expressive vocabulary growth between 6 and 32 months of age are reported. These trajectories allow the equivalent age corresponding to a score to be determined after a brief structured interview with the child's parents that can be conducted in a busy clinical setting. The simplified short forms of the Mandarin Communicative Development Inventories can serve as a clinically useful tool to assess early child language development, providing a practical mean of objectively assessing early language development following early interventions to treat young children with hearing impairment as well as speech and language delays. Objective evidence of language development is essential for achievement of effective (re)habilitation outcomes. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Phyllotactic pattern formation in early stages of cactus ontogeny

    Directory of Open Access Journals (Sweden)

    Edyta M. Gola

    2011-01-01

    Full Text Available Representatives of the family Cactaceae are characterized by a wide range of phyllotaxis. To assess the origin of this diversity, early stages of phyllotactic pattern formation were examined in seedlings. The analysis of the sequence of areole initiation revealed intertribal differences. In seedlings from the Trichocereeae (Gymnocalycium, Rebutia and Notocacteae (Parodia tribes, two opposite cotyledonal areoles developed as the first elements of a pattern. Usually, next pair of areoles was initiated perpendicularly to cotyledonal areoles, starting the decussate pattern. This pattern was subsequently transformed into bijugate or into simple spiral phyllotaxis. In seedlings from the Cacteae tribe (Mammillaria and Thelocactus, cotyledonal areoles were never observed and the first areoles always appeared in the space between cotyledons. It was either areole pair (mainly in Mammillaria, starting a decussate pattern, or a single areole (mainly in Thelocactus quickly followed by areoles spirally arranged, usually in accordance with the main Fibonacci phyllotaxis. Differences in the initial stages of pattern formation do not fully explain the phyllotaxis diversity in mature cacti. Only two, the most common phyllotactic patterns occurred in the early development of studied seedlings, i.e. the main Fibonacci and the decussate pattern. Discrepancy in the range of phyllotactic spectra in seedlings and in mature plants suggests that phyllotaxis diversity emerges during further plant growth. Initial phyllotactic transformations, occurring already in the very early stages, indicate great plasticity of cactus growth and seem to support the hypothesis of the ontogenetic increase of phyllotaxis diversity due to transformations.

  16. Considerations in the early development of biosimilar products.

    Science.gov (United States)

    Li, Edward C; Abbas, Richat; Jacobs, Ira A; Yin, Donghua

    2015-05-01

    The widespread use and patent expiration of many biologics have led to global interest in development of biosimilar products. Because the manufacture of biologics, including biosimilars, is a complex process involving living systems, the development of a biosimilar is more rigorous than the development of a generic small molecule drug. Several regulatory agencies have established or are proposing guidelines that recommend a stepwise process to ensure the efficacy and safety of a biosimilar are highly similar to the reference product. This article also explores the early clinical phase of biosimilar development, which is particularly important to resolving any uncertainties that might remain following in vitro and in vivo evaluations and to enable a selective and targeted approach to Phase III clinical efficacy and safety investigation.

  17. Epigenetics and development of food allergy (FA) in early childhood.

    Science.gov (United States)

    Hong, Xiumei; Wang, Xiaobin

    2014-09-01

    This review aims to highlight the latest advance on epigenetics in the development of food allergy (FA) and to offer future perspectives. FA, a condition caused by an immunoglobulin (Ig) E-mediated hypersensitivity reaction to food, has emerged as a major clinical and public health problem worldwide in light of its increasing prevalence, potential fatality, and significant medical and economic impact. Current evidence supports that epigenetic mechanisms are involved in immune regulation and that the epigenome may represent a key "missing piece" of the etiological puzzle for FA. There are a growing number of population-based epigenetic studies on allergy-related phenotypes, mostly focused on DNA methylation. Previous studies mostly applied candidate-gene approaches and have demonstrated that epigenetic marks are associated with multiple allergic diseases and/or with early-life exposures relevant to allergy development (such as early-life smoking exposure, air pollution, farming environment, and dietary fat). Rapid technological advancements have made unbiased genome-wide DNA methylation studies highly feasible, although there are substantial challenge in study design, data analyses, and interpretation of findings. In conclusion, epigenetics represents both an important knowledge gap and a promising research area for FA. Due to the early onset of FA, epigenetic studies of FA in prospective birth cohorts have the potential to better understand gene-environment interactions and underlying biological mechanisms in FA during critical developmental windows (preconception, in utero, and early childhood) and may lead to new paradigms in the diagnosis, prevention, and management of FA and provide novel targets for future drug discovery and therapies for FA.

  18. [Effects of gap size on seedling natural regeneration in artificial Pinus tabulaeformis plantation].

    Science.gov (United States)

    Han, Wen-Juan; Yuan, Xiao-Qing; Zhang, Wen-Hui

    2012-11-01

    To clarify the effects of gap size created by thinning on the seedling natural regeneration in artificial Pinus tabulaeformis plantation, a plot investigation was conducted to study the ecological factors and the age structure, height, diameter, length of needles, and dry biomass of roots, stems, and needles of 1-10 year-old seedlings in different habitats, and a path analysis was made on the environmental factors affecting the seedling regeneration. Obvious differences were observed in the ecological factors in different size gaps and slope aspects. There lacked of above 3 year-old seedlings in understory and of above 7 year-old seedlings in small gap, and the seedlings of 5 and 6 year-old were lesser in big gap. The 1-10 year-old seedlings could be divided into 3 development phases, i. e. , 1-3 year-old, 4-7 year-old, and 8-10 year-old seedlings, among which, 1-3 year-old seedlings were critical for the establishment and growth of the population. The growth situation of the seedlings in different habitats was in order of big gap in shady slope > big gap in sunny slope > small gap in sunny slope > small gap in shady slope > understory in sunny slope > understory in shady slope. Path analysis showed light intensity had decisive positive effects on the seedling number of different development phases, shrub coverage had decisive negative effects on the seedling number of 4-7 year-old and 8-10 year-old phases, whereas humus dry mass had negative effects on the seedling number of 4-7 year-old but positive effects on the seedling number of 8-10 year-old. It was suggested that in the management of artificial P. tabulaeformis plantation, relatively high intensity thinning combined with shrub clearing should be adopted to provide favorable conditions for the sustainable development of P. tabulaeformis population.

  19. Early somatosensory processing in individuals at risk for developing psychoses

    Directory of Open Access Journals (Sweden)

    Florence eHagenmuller

    2014-09-01

    Full Text Available Human cortical somatosensory evoked potentials (SEPs allow an accurate investigation of thalamocortical and early cortical processing. SEPs reveal a burst of superimposed early (N20 high-frequency oscillations around 600 Hz. Previous studies reported alterations of SEPs in patients with schizophrenia. This study addresses the question whether those alterations are also observable in populations at risk for developing schizophrenia or bipolar disorders. To our knowledge to date, this is the first study investigating SEPs in a population at risk for developing psychoses.Median nerve SEPs were investigated using multichannel EEG in individuals at risk for developing bipolar disorders (n=25, individuals with high-risk status (n= 59 and ultra-high-risk status for schizophrenia (n= 73 and a gender and age-matched control group (n=45. Strengths and latencies of low- and high-frequency components as estimated by dipole source analysis were compared between groups.Low- and high-frequency source activity was reduced in both groups at risk for schizophrenia, in comparison to the group at risk for bipolar disorders. HFO amplitudes were also significant reduced in subjects with high-risk status for schizophrenia compared to healthy controls. These differences were accentuated among cannabis non-users. Reduced N20 source strengths were related to higher positive symptom load.These results suggest that the risk for schizophrenia, in contrast to bipolar disorders, may involve an impairment of early cerebral somatosensory processing. Neurophysiologic alterations in schizophrenia precede the onset of initial psychotic episode and may serve as indicator of vulnerability for developing schizophrenia.

  20. Effects of seed traits variation on seedling performance of the invasive weed, Ambrosia artemisiifolia L.

    Science.gov (United States)

    Ortmans, William; Mahy, Grégory; Monty, Arnaud

    2016-02-01

    Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for annuals, opportunists or invasive plant species. Seedling performance can vary among mothers or populations in response to environmental conditions or under the influence of seed traits. However, very few studies have investigated seed traits variations and their consequences on seedling performance. Specifically, the following questions have been addressed by this work: 1) How the seed traits of the invasive Ambrosia artemisiifolia L. vary among mothers and populations, as well as along the latitude; 2) How do seed traits influence seedling performance; 3) Is the influence on seedlings temperature dependent. With seeds from nine Western Europe ruderal populations, seed traits that can influence seedling development were measured. The seeds were sown into growth chambers with warmer or colder temperature treatments. During seedling growth, performance-related traits were measured. A high variability in seed traits was highlighted. Variation was determined by the mother identity and population, but not latitude. Together, the temperature, population and the identity of the mother had an effect on seedling performance. Seed traits had a relative impact on seedling performance, but this did not appear to be temperature dependent. Seedling performance exhibited a strong plastic response to the temperature, was shaped by the identity of the mother and the population, and was influenced by a number of seed traits.

  1. Early growth and development of later life metabolic disorders.

    Science.gov (United States)

    Foo, Joo-Pin; Mantzoros, Christos

    2013-01-01

    Growth is effected via a complex interaction of genetic, nutritional, environmental and growth factors. Hormonal factors such as the growth hormone (GH) and insulin-like growth factor (IGF) signaling system, the human placental lactogen, and insulin play an integral role in early growth. Genetic factors affecting the GH-IGF system and insulin secretion and actions, and epigenetic mechanisms including DNA methylation have been further implicated as contributory factors. These hormonal systems, on a background of genetic susceptibility, together with other factors including maternal nutrition, placental and environmental factors, regulate not only early growth but also development. These interactions may impact on later health consequences in adult life. Accumulating data in the last few decades on developmental programming and later life metabolic disorders has provided a novel perspective on the possible pathogenesis of metabolic dysregulation. Despite postulations put forward to elucidate the mechanism underlying the association between early growth and later life metabolic disorders, it remains unclear what the dominant factor(s) would be, how any underlying mechanisms interact, or whether these mechanisms are truly causal.

  2. 2种除草剂对黑麦早期幼苗生长的影响%Effect of Two Herbicides on the Growth of Early Seedlings of Rye ( Secale cereale)

    Institute of Scientific and Technical Information of China (English)

    党晨; 高越

    2011-01-01

    [目的]了解除草剂对黑麦幼苗早期生长的影响.[方法]从生理生化和细胞水平分析了2种除草剂[阿特拉津(Atrazine)和甲酰胺草磷(Amiprophos methyl,APM)]对黑麦早期幼苗生长的影响.[结果]Atrazine可明显降低黑麦幼苗叶绿素a、b和可溶性蛋白质的含量.当用0.100和1.000 mg/L Atrazine处理黑麦幼苗16 h时,叶绿素a、b含量分别从对照的1.26 (a)、0.49 (b) mg/g(FW)下降至1.15(a)、0.46 (b) mg/g(FW)和0.81 (a)、0.33 (b) mg/g(FW).可溶性蛋白质含量则随着Atrazine处理浓度的增加而减少.Atrazine对黑麦分生组织细胞有丝分裂和染色体结构无显著影响.APM处理后,黑麦幼苗叶绿素a、b和可溶性蛋白质含量无显著变化,但分生组织细胞有丝分裂和染色体结构变异如桥、多极分裂、滞后染色体和不均等分裂中期细胞数量显著增加.[结论]黑麦中Atrazine使用的临界剂量为0.100~1.000 mg/L,而APM为4.000 mg/L.%[Objective] The aim was to study the effect of herbicide on the growth of early seedlings of rye (Secale cereale). [ Method] Effect of two kinds of herbicide ( Atrazine and APM) on seedling growth of rye was investigated at the physiological, biochemical and cellular level. [Result] The Atrazin significantly decreased the contents of chlorophyll a,b and soluble proteins. Rye seeds were treated with 0. 100 and 1.000 mg/L Atrazine for 16 h, the contents of chlorophyll a and b decreased from 1.26 (a), 0.49 (b) mg/g FW ( control) tol.15 (a),0.46 ( b) mg/g FW (0. 100 mg/L) and 0.81 (a) ,0. 33 ( b) mg/g FW( 1.000 mg/L). The content of soluble protein decreased with the increasing concentration of Atrazin. Atrazin had no significant influence on the cell division and chromosome structure variation. The contents of chlorophyll a, b and soluble proteins had no significantly change under the treatment of APM, but the number of chromosome structure variation such as chromosome bridge,multipolar division cells

  3. Effect of Two Herbicides on the Growth of Early Seedlings of Rye(Secale cereale)%两种除草剂对黑麦早期幼苗生长的影响

    Institute of Scientific and Technical Information of China (English)

    党晨; 高越

    2011-01-01

    [Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye(Secale cereale).[Method]Effect of two kinds of herbicide(Atrazine and APM)on seedling growth of rye was investigated at the physiological,biochemical and cellular level.[Result]The Atrazin significantly decreased the contents of chlorophyll a,b and soluble proteins.Rye seeds were treated with 0.01-1 mg/L Atrazine for 16 h,the contents of chlorophyll a and b decreased from 1.26(a),0.49(b)mg/g FW(control)to 1.15(a),0.46(b)mg/g FW(0.1 mg/L)and 0.81(a),0.33(b)mg/g FW(1.0 mg/L).The content of soluble protein decreased with the increasing concentration of Atrazin.Atrazin had no significant influence on the cell division and chromosome structure variation.The contents of chlorophyll a,b and soluble proteins had no significantly change under the treatment of APM,but the number of chromosome structure variation such as chromosome bridge,multipolar division cells,lagging chromosome and unequal division cells increased significantly.[Conclusion]The critical concentration of Atrazine was 0.1-1.0 mg/L and 4 mg/L of APM in rye.%[目的]了解除草剂对黑麦幼苗早期生长的影响。[方法]从生理生化和细胞水平分析了2种除草剂[阿特拉津(Atrazine)和甲酰胺草磷(Amiprophos methyl,APM)]对黑麦早期幼苗生长的影响。[结果]Atrazine可明显降低黑麦幼苗叶绿素a、b和可溶性蛋白质的含量。当用0.100和1.000mg/L Atrazine处理黑麦幼苗16h时,叶绿素a、b含量分别从对照的1.26(a)、0.49(b)mg/g(FW)下降至1.15(a)、0.46(b)mg/g(FW)和0.81(a)、0.33(b)mg/g(FW)。可溶性蛋白质含量则随着Atrazine处理浓度的增加而减少。Atrazine对黑麦分生组织细胞有丝分裂和染色体结构无显著影响。APM处理后,黑麦幼苗叶绿素a、b和可溶性蛋白质含量无显著变化,但分生组织细胞有丝分裂和染色

  4. A gene expression atlas of early craniofacial development.

    Science.gov (United States)

    Brunskill, Eric W; Potter, Andrew S; Distasio, Andrew; Dexheimer, Phillip; Plassard, Andrew; Aronow, Bruce J; Potter, S Steven

    2014-07-15

    We present a gene expression atlas of early mouse craniofacial development. Laser capture microdissection (LCM) was used to isolate cells from the principal critical microregions, whose development, differentiation and signaling interactions are responsible for the construction of the mammalian face. At E8.5, as migrating neural crest cells begin to exit the neural fold/epidermal ectoderm boundary, we examined the cranial mesenchyme, composed of mixed neural crest and paraxial mesoderm cells, as well as cells from adjacent neuroepithelium. At E9.5 cells from the cranial mesenchyme, overlying olfactory placode/epidermal ectoderm, and underlying neuroepithelium, as well as the emerging mandibular and maxillary arches were sampled. At E10.5, as the facial prominences form, cells from the medial and lateral prominences, the olfactory pit, multiple discrete regions of underlying neuroepithelium, the mandibular and maxillary arches, including both their mesenchymal and ectodermal components, as well as Rathke's pouch, were similarly sampled and profiled using both microarray and RNA-seq technologies. Further, we performed single cell studies to better define the gene expression states of the early E8.5 pioneer neural crest cells and paraxial mesoderm. Taken together, and analyzable by a variety of biological network approaches, these data provide a complementing and cross validating resource capable of fueling discovery of novel compartment specific markers and signatures whose combinatorial interactions of transcription factors and growth factors/receptors are responsible for providing the master genetic blueprint for craniofacial development.

  5. Proteomic analysis of early seed development in Pinus massoniana L.

    Science.gov (United States)

    Zhen, Yan; Zhao, Zhen-Zhou; Zheng, Ren-Hua; Shi, Jisen

    2012-05-01

    Understanding seed development is important for large-scale propagation and germplasm conservation for the Masson pine. We undertook a proteomic analysis of Masson pine seeds during the early stages of embryogenesis. Two-dimensional difference gel electrophoresis (2D DIGE) was used to quantify the differences in protein expression during early seed development. Using electrospray ionization mass spectrometry/mass spectrometry, we identified proteins from 43 gel spots that had been excised from preparative "pick" gels. Proteins involved in carbon metabolism were identified and were predominantly expressed at higher levels during the cleavage polyembryony and columnar embryo stages. Functional annotation of one seed protein revealed it involvement in programmed cell death and translation of selective mRNAs, which may play an important role in subordinate embryo elimination and suspensor degeneration in polyembryonic seed gymnosperms. Other identified proteins were associated with protein folding, nitrogen metabolism, disease/defense response, and protein storage, synthesis and stabilization. The comprehensive protein expression profiles generated by this study will provide new insights into the complex developmental process of seed development in Masson pine.

  6. Understanding Substorms in the Magnetotail: Early Development and Recent Progress

    Institute of Scientific and Technical Information of China (English)

    A.Nishida

    2011-01-01

    This is a concise review of physics of the substorm in the magnetotail.It consists of two parts.The first part summarizes historical developments in the early days of the space age (1960-1975) when the basic concepts such as magnetotail and reconnection were established and the leading model of the substorm was introduced.The second part is an overview of the research conducted in recent years (1995-2010) when very significant advances have been achieved in understanding the substorm physics by virtue of several major satellites missions that addressed the magnetotail physics intensively.

  7. Comparison of early gestational development between natural and stimulated pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Soon Ae; Ahn, M. O.; Yoon, T. K.; Cha, G. Y. [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1990-12-15

    In order to assess the difference in growth and development between the stimulated and natural pregnancies, we compared the sonographic measurement of early embryos from the fifth to seventh gestational week, in terms of mean size of gestational sac, crown rump length, fetal heart rate and yolk sac size between 26 ovulation stimulated pregnancies and 38 natural pre gnancies. The two groups were compared by multiple regression analysis, The data suggest that there is attend that embryos smaller in stimulated pregnancies though significant statistical differences was not proved

  8. APECS: A Network for Polar Early Career Scientist Professional Development

    Science.gov (United States)

    Enderlin, E. M.

    2014-12-01

    The Association of Polar Early Career Researchers (APECS) is an international and interdisciplinary organization for undergraduate and graduate students, postdoctoral researchers, early faculty members, educators and others with interests in the polar regions, alpine regions and the wider Cryosphere. APECS is a scientific, non-profit organization with free individual membership that aims to stimulate research collaborations and develop effective future leaders in polar research, education, and outreach. APECS grew out of the 4th International Polar Year (2007-08), which emphasized the need to stimulate and nurture the next generation of scientists in order to improve the understanding and communication of the polar regions and its global connections. The APECS organizational structure includes a Council and an elected Executive Committee that are supported by a Directorate. These positions are open to all individual members through a democratic process. The APECS Directorate is funded by the Norwegian Research Council, the University of Tromsø and the Norwegian Polar Institute and is hosted by the University of Tromsø. Early career scientists benefit from a range of activities hosted/organized by APECS. Every year, numerous activities are run with partner organizations and in conjunction with major polar conferences and meetings. In-person and online panels and workshops focus on a range of topics, from developing field skills to applying for a job after graduate school. Career development webinars are hosted each fall and topical research webinars are hosted throughout the year and archived online (http://www.apecs.is). The APECS website also contains abundant information on polar news, upcoming conferences and meetings, and job postings for early career scientists. To better respond to members' needs, APECS has national/regional committees that are linked to the international overarching organization. Many of these committees organize regional meetings or

  9. Retinoic acid synthesis and functions in early embryonic development

    Directory of Open Access Journals (Sweden)

    Kam Richard Kin Ting

    2012-03-01

    Full Text Available Abstract Retinoic acid (RA is a morphogen derived from retinol (vitamin A that plays important roles in cell growth, differentiation, and organogenesis. The production of RA from retinol requires two consecutive enzymatic reactions catalyzed by different sets of dehydrogenases. The retinol is first oxidized into retinal, which is then oxidized into RA. The RA interacts with retinoic acid receptor (RAR and retinoic acid X receptor (RXR which then regulate the target gene expression. In this review, we have discussed the metabolism of RA and the important components of RA signaling pathway, and highlighted current understanding of the functions of RA during early embryonic development.

  10. Seedling responses to water pulses in shrubs with contrasting histories of grassland encroachment.

    Science.gov (United States)

    Woods, Steven R; Archer, Steven R; Schwinning, Susan

    2014-01-01

    Woody plant encroachment into grasslands has occurred worldwide, but it is unclear why some tree and shrub species have been markedly more successful than others. For example, Prosopis velutina has proliferated in many grasslands of the Sonoran Desert in North America over the past century, while other shrub species with similar growth form and life history, such as Acacia greggii, have not. We conducted a glasshouse experiment to assess whether differences in early seedling development could help explain why one species and not the other came to dominate many Sonoran Desert grasslands. We established eight watering treatments mimicking a range of natural precipitation patterns and harvested seedlings 16 or 17 days after germination. A. greggii had nearly 7 times more seed mass than P. velutina, but P. velutina emerged earlier (by 3.0±0.3 d) and grew faster (by 8.7±0.5 mg d⁻¹). Shoot mass at harvest was higher in A. greggii (99±6 mg seedling⁻¹) than in P. velutina (74±2 mg seedling⁻¹), but there was no significant difference in root mass (54±3 and 49±2 mg seedling⁻¹, respectively). Taproot elongation was differentially sensitive to water supply: under the highest initial watering pulse, taproots were 52±19 mm longer in P. velutina than in A. greggii. Enhanced taproot elongation under favorable rainfall conditions could give nascent P. velutina seedlings growth and survivorship advantages by helping reduce competition with grasses and maintain contact with soil water during drought. Conversely, A. greggii's greater investment in mass per seed appeared to provide little return in early seedling growth. We suggest that such differences in recruitment traits and their sensitivities to environmental conditions may help explain ecological differences between species that are highly similar as adults and help identify pivotal drivers of shrub encroachment into grasslands.

  11. Seedling responses to water pulses in shrubs with contrasting histories of grassland encroachment.

    Directory of Open Access Journals (Sweden)

    Steven R Woods

    Full Text Available Woody plant encroachment into grasslands has occurred worldwide, but it is unclear why some tree and shrub species have been markedly more successful than others. For example, Prosopis velutina has proliferated in many grasslands of the Sonoran Desert in North America over the past century, while other shrub species with similar growth form and life history, such as Acacia greggii, have not. We conducted a glasshouse experiment to assess whether differences in early seedling development could help explain why one species and not the other came to dominate many Sonoran Desert grasslands. We established eight watering treatments mimicking a range of natural precipitation patterns and harvested seedlings 16 or 17 days after germination. A. greggii had nearly 7 times more seed mass than P. velutina, but P. velutina emerged earlier (by 3.0±0.3 d and grew faster (by 8.7±0.5 mg d⁻¹. Shoot mass at harvest was higher in A. greggii (99±6 mg seedling⁻¹ than in P. velutina (74±2 mg seedling⁻¹, but there was no significant difference in root mass (54±3 and 49±2 mg seedling⁻¹, respectively. Taproot elongation was differentially sensitive to water supply: under the highest initial watering pulse, taproots were 52±19 mm longer in P. velutina than in A. greggii. Enhanced taproot elongation under favorable rainfall conditions could give nascent P. velutina seedlings growth and survivorship advantages by helping reduce competition with grasses and maintain contact with soil water during drought. Conversely, A. greggii's greater investment in mass per seed appeared to provide little return in early seedling growth. We suggest that such differences in recruitment traits and their sensitivities to environmental conditions may help explain ecological differences between species that are highly similar as adults and help identify pivotal drivers of shrub encroachment into grasslands.

  12. Allelopathy of Camelina sativa Boiss. (Brassicaceae) on germination and early development of Bidens pilosa (L.) and Glycine max (L.) Merr

    OpenAIRE

    Jéssica da Silva; Andréa Maria Teixeira Fortes; Fernanda Melo Gomes; Tassiane Terezinha Pinto; Thaliny Bonamigo; Nayara Parisoto Boiago

    2011-01-01

    This study evaluated the possible presence of allelopathic potential in camelina, as well as its effect on germination and early growth of soybean seedlings and beggarticks, in order, to verify the possibility of cultivating it with soybeans in a culture rotation system and its use as a herbicide. The experiments were carried out at the Laboratory of Plant Physiology of Universidade Estadual do Oeste do Paraná, Cascavel, Paraná, Brazil. The design was completely randomized and the evaluations...

  13. Over-expression of StAPX in tobacco improves seed germination and increases early seedling tolerance to salinity and osmotic stresses.

    Science.gov (United States)

    Sun, Wei-Hong; Duan, Ming; Shu, De-Feng; Yang, Sha; Meng, Qing-Wei

    2010-08-01

    Ascorbate peroxidase plays a key role in scavenging reactive oxygen species under environmental stresses and in protecting plant cells against toxic effects. The Solanum lycopersicum thylakoid-bound ascorbate peroxidase gene (StAPX) was introduced into tobacco under the control of the cauliflower mosaic virus 35S promoter. Transformants were selected for their ability to grow on medium containing kanamycin. RNA gel blot analysis confirmed that StAPX was transferred into the tobacco genome and StAPX was induced by salt and osmotic stresses in tomato leaves. Over-expression of StAPX in tobacco improved seed germination rate and elevated stress tolerance during post-germination development. Two transgenic lines showed higher APX activity and accumulated less hydrogen peroxide than wild-type plants after stress treatments. The photosynthetic rates, the root lengths, the fresh and dry weights of the transgenic lines were distinctly higher than those of wild-type plants under stress conditions. Results indicated that the over-expression of StAPX had enhanced tolerance to salt stress and osmotic stress in transgenic tobacco plants.

  14. Emergence and initial development of Mimosa caesalpiniifolia Benth. seedlings for different substrates = Emergência e desenvolvimento inicial de plântulas de Mimosa caesalpiniifolia Benth. em função de diferentes substratos

    Directory of Open Access Journals (Sweden)

    Rômulo Magno Oliveira de Freitas

    2012-04-01

    Full Text Available The present study assessed the effects of different substrates on the emergence and initial development of Mimosa caesalpiniifolia Benth seedlings. For this purpose an experiment was done in a greenhouse of the Department of Plant Sciences of Universidade Federal Rural do Semi-Árido (UFERSA, Mossoró-RN. The statistical design was completely randomized (CRD, where treatments were composed of nine substrates (T1: vermiculite, T2: coconut fiber, T3: trade hortimix®, T4: vermiculite, coconut fiber and compost (1: 1:1, T5: coconut fiber and compost (1:1, T6: coconut fiber and compost (1:2,T7: vermiculite and compost (1:1, T8, vermiculite and compost organic (1:2 and T9: organic compost. All treatments were represented by four replications containing 25 seeds. The following variables were evaluated: emergency percentage, emergence rate index, length of shoot and root, stem diameter, dry leaves, stem, root and total leaf area, specific leaf area, leaf area ratio, and leaf weight ratio. Data were submitted to the Tukey test at 5% probability. The coconut fiber substrates, commercial hortimix® and vermiculite proved superior promoted good emergence and early development of seedlings. The mixture of vermiculite, coconut fiber and compost (1:1:1, coconut fiber and compost (1:1, coconut fiber and compost (1:2 and organic compost and vermiculite (1: 1 was not shown to be adequate for the cultivation of seedlings. There was no emergency in the pure organic compound in the mixture of compost and vermiculite (1:2.Key words - Vermiculite. Organic compost. Coconut fiber. Sabiá. Substrates. = Objetivou-se com o presente trabalho avaliar o efeito de diferentes substratos na emergência e desenvolvimento inicial de plântulas de sabiá (Mimosa caesalpiniifolia Benth.. Para isso, foi instalado um experimento em casa de vegetação do Departamento de Ciências Vegetais da Universidade Federal Rural do Semi-árido (UFERSA, Mossoró-RN. O delineamento estat

  15. Relationships between established seedling survival and growth in evergreen broad-leaved forest in Tiantong

    Directory of Open Access Journals (Sweden)

    Heming Liu

    2017-01-01

    Full Text Available Community seedling regeneration is a crucial process for maintaining species coexistence. The stage from which an established seedling becomes a new reproductive individual is one of the most important components of community regeneration, and influences the community recruitment pattern. However, the short-term mortality of established seedlings is lower than newly germinated seedlings, and previous studies have not been able to analyze the effect of biotic neighborhoods and abiotic micro-habitat factors on established seedling survival perfectly. Therefore, we suggest that the growth status of established seedlings could predict established seedling survival during development, and analyze the effects of these biotic and abiotic factors on established seedling growth, in order to indirectly estimate their effects on established seedling survival. To test this hypothesis, we selected established seedlings in the 20 ha forest dynamics plot in Tiantong as samples. Then, we used generalized linear mixed models to assess the effects of relative growth rate, biotic neighborhood factors (conspecific/heterospecific adult neighborhood indices, density of conspecific/heterospecific seedling neighbors, the amount of conspecific/heterospecific leaf litter from neighbors and abiotic micro-habitat factors (canopy openness, herbaceous coverage, elevation, slope, aspect, pH value, total nitrogen and total phosphorus in the soil on short-term established seedling survival rates. We used linear mixed models to assess the effects of biotic neighborhood factors and abiotic micro-habitat factors on relative growth rates of established seedlings. Results showed that relative growth rates have a significant, positive effect on established seedling survival, and this factor is the most important factor among potential influencing factors. In addition, canopy openness, as only one significant influencing factor, has a positive effect on relative growth rates of

  16. Early developing celiac disease in children with cerebral palsy.

    Science.gov (United States)

    Stenberg, Reidun; Kaukinen, Katri; Bengtsson, Mats; Lindberg, Eva; Dahle, Charlotte

    2011-12-01

    We have reported on increased levels of antibodies against gliadin and/or transglutaminase 2 (TG2) in children with cerebral palsy (CP) but without having increased prevalence of celiac disease (CD). The aim of the present study was to evaluate whether these children have mucosal signs of early developing CD, human leukocyte antigen (HLA)-DQ2/DQ8, and antibodies against deamidated gliadin peptides (DGP). Stored blood samples from 16 children with CP were analyzed regarding HLA-DQ2/DQ8 and anti-DGP antibodies. HLA-DQ2/DQ8 were analyzed by polymerase chain reaction sequence-specific oligonucleotide probes. Anti-DGP antibodies were analyzed with enzyme-linked immunosorbent assay. Small-bowel biopsies from 15 of these children were available for immunohistochemistry regarding IgA colocalized with TG2, densities of α/β+ and γ/δ+ intraepithelial lymphocytes. Mucosal immunoglobulin A (IgA) deposits colocalized with TG2 were found in the small-bowel biopsy from 1 patient with serum IgA-class anti-TG2 antibodies, HLA-DQ2, and gastrointestinal complaints. Another 2 children had slightly increased numbers of mucosal α/β+ and/or γ/δ+ intraepithelial lymphocytes. In total, 10 of 16 children were HLA-DQ2 and/or DQ8-positive. Anti-DGP antibodies were detected in sera from 4 of 16 children. In the present study, 1 child with CP had IgA colocalizing with TG2 in the small-bowel mucosa, suggesting CD at an early stage. Although the majority of children with CP and elevated levels of CD-related seromarkers are HLA-DQ2 and/or DQ8-positive, they have neither classical nor early developing CD.

  17. Early Requestive Development in Consecutive Third Language Learning

    Science.gov (United States)

    Safont-Jorda, Maria-Pilar

    2011-01-01

    While research on early simultaneous bilingual acquisition is well-documented, studies on multiple language acquisition in early childhood are still needed. Existing studies have mainly focused on early simultaneous acquisition of three or more languages. Some attention has already been paid to early pragmatic differentiation and cross-linguistic…

  18. Early Requestive Development in Consecutive Third Language Learning

    Science.gov (United States)

    Safont-Jorda, Maria-Pilar

    2011-01-01

    While research on early simultaneous bilingual acquisition is well-documented, studies on multiple language acquisition in early childhood are still needed. Existing studies have mainly focused on early simultaneous acquisition of three or more languages. Some attention has already been paid to early pragmatic differentiation and cross-linguistic…

  19. Early Neurobehavioral Development of Mice Lacking Endogenous PACAP.

    Science.gov (United States)

    Farkas, Jozsef; Sandor, Balazs; Tamas, Andrea; Kiss, Peter; Hashimoto, Hitoshi; Nagy, Andras D; Fulop, Balazs D; Juhasz, Tamas; Manavalan, Sridharan; Reglodi, Dora

    2017-04-01

    Pituitary adenylate cyclase activating polypeptide (PACAP) is a multifunctional neuropeptide. In addition to its diverse physiological roles, PACAP has important functions in the embryonic development of various tissues, and it is also considered as a trophic factor during development and in the case of neuronal injuries. Data suggest that the development of the nervous system is severely affected by the lack of endogenous PACAP. Short-term neurofunctional outcome correlates with long-term functional deficits; however, the early neurobehavioral development of PACAP-deficient mice has not yet been evaluated. Therefore, the aim of the present study was to describe the postnatal development of physical signs and neurological reflexes in mice partially or completely lacking PACAP. We examined developmental hallmarks during the first 3 weeks of the postnatal period, during which period most neurological reflexes and motor coordination show most intensive development, and we describe the neurobehavioral development using a complex battery of tests. In the present study, we found that PACAP-deficient mice had slower weight gain throughout the observation period. Interestingly, mice partially lacking PACAP weighed significantly less than homozygous mice. There was no difference between male and female mice during the first 3 weeks. Some other signs were also more severely affected in the heterozygous mice than in the homozygous mice, such as air righting, grasp, and gait initiation reflexes. Interestingly, incisor teeth erupted earlier in mice lacking PACAP. Motor coordination, shown by the number of foot-faults on an elevated grid, was also less developed in PACAP-deficient mice. In summary, our results show that mice lacking endogenous PACAP have slower weight gain during the first weeks of development and slower neurobehavioral development regarding a few developmental hallmarks.

  20. Early lexical development in Spanish-speaking infants and toddlers.

    Science.gov (United States)

    Jackson-Maldonado, D; Thal, D; Marchman, V; Bates, E; Gutierrez-Clellen, V

    1993-10-01

    This paper describes the early lexical development of a group of 328 normal Spanish-speaking children aged 0;8 to 2;7. First the development and structure of a new parent report instrument, Inventario del Desarollo de Habilidades Communicativas is described. Then five studies carried out with the instrument are presented. In the first study vocabulary development of Spanish-speaking infants and toddlers is compared to that of English-speaking infants and toddlers. The English data were gathered using a comparable parental report, the MacArthur Communicative Development Inventories. In the second study the general characteristics of Spanish language acquisition, and the effects of various demographic factors on that process, are examined. Study 3 examines the differential effects of three methods of collecting the data (mail-in, personal interview, and clinic waiting room administration). Studies 4 and 5 document the reliability and validity of the instrument. Results show that the trajectories of development are very similar for Spanish- and English-speaking children in this age range, that children from varying social groups develop similarly, and that mail-in and personal interview administration techniques produce comparable results. Inventories administered in a medical clinic waiting room, on the other hand, produced lower estimates of toddler vocabulary than the other two models.

  1. [Development and the developmental disorders of human brain. I. Early development of the cerebrum

    NARCIS (Netherlands)

    Donkelaar, H.J. ten; Wesseling, P.; Lammens, M.M.Y.; Renier, W.O.; Mullaart, R.A.; Thijssen, H.O.M.

    2001-01-01

    The recent discovery of many genes that regulate brain development is revolutionizing our knowledge of neuroembryology and, moreover, our understanding of how gene defects cause human birth defects. The first 8 weeks of the development of the cerebrum can be subdivided into 23 stages, with early

  2. Early Development of the Gut Microbiota and Immune Health

    Directory of Open Access Journals (Sweden)

    M. Pilar Francino

    2014-09-01

    Full Text Available In recent years, the increase in human microbiome research brought about by the rapidly evolving “omic” technologies has established that the balance among the microbial groups present in the human gut, and their multipronged interactions with the host, are crucial for health. On the other hand, epidemiological and experimental support has also grown for the ‘early programming hypothesis’, according to which factors that act in utero and early in life program the risks for adverse health outcomes later on. The microbiota of the gut develops during infancy, in close interaction with immune development, and with extensive variability across individuals. It follows that the specific process of gut colonization and the microbe-host interactions established in an individual during this period have the potential to represent main determinants of life-long propensity to immune disease. Although much remains to be learnt on the progression of events by which the gut microbiota becomes established and initiates its intimate relationships with the host, and on the long-term repercussions of this process, recent works have advanced significatively in this direction.

  3. Development of children’s early understanding of numeric structure

    Directory of Open Access Journals (Sweden)

    Vasilyeva, Marina

    2016-09-01

    Full Text Available Understanding of the base-10 structure of multi-digit numbers is one of the critical aspects in early mathematics learning. It has been documented that children from different countries vary in their use of base-10 representations. Questions concerning potential sources of this variability have been debated for decades. One commonly posited explanation is that some languages provide explicit cues about the structure of multi-digit numbers, facilitating the development of base-10 representations. In the present study, we tested this view against an alternative view, positing that variability in children’s learning of numeric structure may reflect differences in their experiences with numbers. The study examined kindergartners and first-graders from four countries: Taiwan, South Korea, the USA, and Russia. Results showed that the use of base-10 representations by American first-graders increased dramatically over the last decades, following changes in curricular guidelines. First-graders across the four countries showed some differences in performance (however, not consistent with the language account, whereas kindergartners performed comparably despite the differences in their languages. The results suggest that the nature of early math instruction may be critical for children’s developing understanding of numeric structure.

  4. Dihydroartemisinin promotes angiogenesis during the early embryonic development of zebrafish

    Institute of Scientific and Technical Information of China (English)

    Qian BA; Juan DUAN; Jia-qiang TIAN; Zi-liang WANG; Tao CHEN; Xiao-guang LI; Pei-zhan CHEN

    2013-01-01

    Aim:To investigate the embryotoxicity of dihydroartemisinin (DHA),the main active metabolite of artemisinin,in zebrafish,and explore the corresponding mechanisms.Methods:The embryos of wild type and TG (flk1:GFP) transgenic zebrafish were exposed to DHA.Developmental phenotypes of the embryos were observed.Development of blood vessels was directly observed in living embryos of TG (flk1:GFP) transgenic zebrafish under fluorescence microscope.The expression of angiogenesis marker genes vegfa,flk1,and flt1 in the embryos was detected using real-time PCR and RNA in situ hybridization assays.Results:Exposure to DHA (1-10 mg/L) dose-dependently caused abnormal zebrafish embryonic phenotypes in the early developmental stage.Furthermore,exposure to DHA (10 mg/L) resulted in more pronounced embryonic angiogenesis in TG (flk1:GFP)zebrafish line.Exposure to DHA (10 mg/L) significantly increased the mRNA expression of vegfa,flk1,and flt1 in the embryos.Knockdown of the ilk1 protein partially blocked the effects of DHA on embryogenesis.Conclusion:DHA causes abnormal embryonic phenotypes and promotes angiogenesis in zebrafish early embryonic development,demonstrating the potential embryotoxicity of DHA.

  5. 茶树幼苗发育过程中儿茶素合成与积累变化的研究%Catechins synthesis and accumulation in tea seedlings at different development stages

    Institute of Scientific and Technical Information of China (English)

    单育; 夏涛; 李伟伟; 王云生; 刘亚军; 王弘雪; 王晓帆; 卢忠尉; 田艳维; 高丽萍

    2011-01-01

    The tea seedlings at different development stages were taken as experimental materials, and the contents of catechins and the expressions of genes related to catechin synthesis in tea leaves, stems and roots of the tea seedlings at different development stages were analyzed using HPLC and qRT-PCR techniques. During the tea seedling development stages, we find that the content of catechins in different organs show different trends.The content of catechins in leaves (DW) were 79.99, 57.69, 49.29 and 33.26 mg·g-1 when the seedlings growing for 25 days, 45 days, 75 days and 90 days, showing a downtrend; while the content of catechins (DW) were 14.40, 11.89, 8.54 and 9.29 mg·g-1 in stems and the content of catechins (DW) were 1.03, 0.60,0.82 and 1.62 mg·g-1 in roots. We can find six kinds of catechins in 25 day's tea seedlings and can not found ester type catechins in tea roots except for in 10 day's seedling. Expressions of the related genes involved in phenylpropanoid biosynthetic pathway showed remarkable difference in different organs at different growth stages.%以茶树幼苗为材料,以HPLC,qRT-PCR为分析手段,分析了茶树幼苗发育过程中根茎叶的儿茶素含量变化及相关合成基因的表达差异.结果显示,在发育过程中,不同器官中儿茶素总量呈现不同的变化规律,在幼苗发育25 d,45 d.75 d和90 d时,茶树叶片的儿茶素含量(干重)呈下降趋势,分别为79.99.57.69,49.29和33.26mg·g-1;茎中(干重)的为14.40.11.89,8.54和 9.29 mg·g-1;根中的含量(干重)很低,分别为1.03,0.60,0.82和1.62mg·g-1;在发育25 d的茶树幼苗茎叶中6种儿茶素单体均可以检测到;根中缺乏酯型儿茶素,但在发育10 d的根中却可以检测到.在茶树幼苗不同器官中,酚类物质合成相关基因表达有较大的差异性.

  6. Physiological and biochemical characterization of the assai palm (Euterpe oleracea Mart. during seed germination and seedling growth under aerobic and anaerobic conditions

    Directory of Open Access Journals (Sweden)

    José Francisco de Carvalho Gonçalves

    2010-12-01

    Full Text Available Physiological and biochemical aspects of assai palm during seed germination and early seedling growth were investigated. Seeds collected from plants growing in flooded and upland forests were used to determine the influence of normoxic (aerobic and anoxic (anaerobic conditions in germination and the initial and average time of development in the roots and shoots. After 75 days, seedlings germinated under normoxia were transferred to trays and submitted to flooding. Seed reserves (lipids, proteins, soluble sugars and starch were monitored for quiescent and germinated seeds maintained under normoxic and anoxic conditions, as well as after 5, 10 and 20 days of seedling growth. Alcohol dehydrogenase (ADH activity was quantified in roots and leaves of seedlings without or with flooding (partial and total. Seeds were not able to germinate under anoxia. Different strategies of storage mobilization of lipids, proteins, soluble sugars and starch were observed in seeds of each environment. ADH activity was induced by anoxia, with the highest level observed in the leaves. This study showed that, under normoxic conditions, the best developmental performance of assai palm seeds, from flooded or upland forest areas, during germination was associated with primary metabolites mobilization and seedling flooding tolerance with increased ADH activity. We conclude that the assai palm is well adapted to the anoxic conditions provoked by flooding.

  7. Early Vocabulary Development of Australian Indigenous Children: Identifying Strengths

    Directory of Open Access Journals (Sweden)

    Brad M. Farrant

    2014-01-01

    Full Text Available The current study sought to increase our understanding of the factors involved in the early vocabulary development of Australian Indigenous children. Data from the Longitudinal Study of Indigenous Children were available for 573 Indigenous children (291 boys who spoke English (M=37.0 months, SD=5.4 months, at wave 3. Data were also available for 86 children (51 boys who spoke an Indigenous language (M=37.1 months, SD=6.0 months, at wave 3. As hypothesised, higher levels of parent-child book reading and having more children’s books in the home were associated with better English vocabulary development. Oral storytelling in Indigenous language was a significant predictor of the size of children’s Indigenous vocabulary.

  8. Language, bilingualism, and executive functioning in early development.

    Science.gov (United States)

    Morton, J Bruce

    2010-12-01

    Okanda, et al. (2010) reported new evidence concerning associations between language ability, bilingualism, and executive functioning early in development. The paper adds to a growing body of literature suggesting that bilingualism is associated with advantages in executive functioning generally, and the Dimensional Change Card Sort task in particular. However, as with all findings that hinge on between-group comparisons, there is a need to exercise caution before drawing firm conclusions about the effects of bilingualism on the development of executive control. Several lines of recent evidence are outlined that challenge key assumptions underlying the standard account of the bilingual advantage. Okanda, et al.'s findings are discussed in light of this evidence.

  9. Modeling and managing risk early in software development

    Science.gov (United States)

    Briand, Lionel C.; Thomas, William M.; Hetmanski, Christopher J.

    1993-01-01

    In order to improve the quality of the software development process, we need to be able to build empirical multivariate models based on data collectable early in the software process. These models need to be both useful for prediction and easy to interpret, so that remedial actions may be taken in order to control and optimize the development process. We present an automated modeling technique which can be used as an alternative to regression techniques. We show how it can be used to facilitate the identification and aid the interpretation of the significant trends which characterize 'high risk' components in several Ada systems. Finally, we evaluate the effectiveness of our technique based on a comparison with logistic regression based models.

  10. A rapid and robust method of identifying transformed Arabidopsis thaliana seedlings following floral dip transformation

    Directory of Open Access Journals (Sweden)

    Gray John C

    2006-11-01

    Full Text Available Abstract Background The floral dip method of transformation by immersion of inflorescences in a suspension of Agrobacterium is the method of choice for Arabidopsis transformation. The presence of a marker, usually antibiotic- or herbicide-resistance, allows identification of transformed seedlings from untransformed seedlings. Seedling selection is a lengthy process which does not always lead to easily identifiable transformants. Selection for kanamycin-, phosphinothricin- and hygromycin B-resistance commonly takes 7–10 d and high seedling density and fungal contamination may result in failure to recover transformants. Results A method for identifying transformed seedlings in as little as 3.25 d has been developed. Arabidopsis T1 seeds obtained after floral dip transformation are plated on 1% agar containing MS medium and kanamycin, phosphinothricin or hygromycin B, as appropriate. After a 2-d stratification period, seeds are subjected to a regime of 4–6 h light, 48 h dark and 24 h light (3.25 d. Kanamycin-resistant and phosphinothricin-resistant seedlings are easily distinguished from non-resistant seedlings by green expanded cotyledons whereas non-resistant seedlings have pale unexpanded cotyledons. Seedlings grown on hygromycin B differ from those grown on kanamycin and phosphinothricin as both resistant and non-resistant seedlings are green. However, hygromycin B-resistant seedlings are easily identified as they have long hypocotyls (0.8–1.0 cm whereas non-resistant seedlings have short hypocotyls (0.2–0.4 cm. Conclusion The method presented here is an improvement on current selection methods as it allows quicker identification of transformed seedlings: transformed seedlings are easily discernable from non-transformants in as little as 3.25 d in comparison to the 7–10 d required for selection using current protocols.

  11. Root starch storage and allocation patterns in seeder and resprouter seedlings of two Cape Erica (Ericaceae) species.

    Science.gov (United States)

    Verdaguer, Dolors; Ojeda, Fernando

    2002-08-01

    Post-fire sprouting of dormant buds in resprouter plants is facilitated by stored carbohydrate reserves, with starch being the critical reserve. Starch is mainly stored in xylem parenchyma ray tissue of woody underground organs, such as burls, lignotubers, and roots. We carried out a comparative analysis of the pattern of starch storage and the proportion of parenchymatic ray tissue in the upper root or cotyledonary region of seedlings from seeder and resprouter forms within two Cape Erica (Ericaceae) species: E. coccinea L. and E. calycina L., which were raised in the greenhouse under controlled irrigation. We also explored the root-to-shoot allocation patterns of seeder and resprouter seedlings in these two species. Resprouter seedlings of both species showed higher relative amounts of upper-root starch and upper-root storage tissue as well as a higher root-to-shoot allocation than their seeder counterparts. Pronounced swelling of the upper root region suggests ontogenetic development of a lignotuber in the resprouter forms of the two Erica species. The distinct allocation of starch in roots seems to be genetically determined and would account for the apparent differences in the root-to-shoot allocation patterns between both regeneration forms from the early seedling stage.

  12. Dual effects of fluoxetine on mouse early embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang-Woon [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University, Changwon 630-723 (Korea, Republic of); Choe, Changyong [National Institute of Animal Science, RDA, Cheonan 330-801 (Korea, Republic of); Kim, Eun-Jin [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Lee, Jae-Ik [Department of Obstetrics and Gynecology, Gyeongsang National University Hospital, Jinju 660-702 (Korea, Republic of); Yoon, Sook-Young [Fertility Center of CHA Gangnam Medical Center, CHA University, Seoul 135-081 (Korea, Republic of); Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Kang, Dawon, E-mail: dawon@gnu.ac.kr [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of)

    2012-11-15

    Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K{sup +} channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from Ca

  13. Population biological characteristics and yield of early rice of throwing transplanting under seedling-increase and nitrogen-reduction measures%增苗节氮对早稻抛秧群体生物学特性及产量的影响

    Institute of Scientific and Technical Information of China (English)

    李超; 陈恺林; 刘洋; 杨光立; 汤文光; 胡杨; 张玉烛

    2014-01-01

    The biological characteristics of population of rice ‘Xiangzhaoxian 45’ of throwing transplanting under three nitrogen levels [N1: 105 kg(N)·hm-2 (low nitrogen dose); N2: 135 kg(N)·hm-2 (low nitrogen dose); N3: 165 kg(N)·hm-2 (regular nitrogen dose)] combined with 3 seedling densities [M1: 0.27 million hills per hectare (regular seedling rate); M2:0.315 million hills per hectare (high seedling rate);M3:0.36 million hills per hectare (high seedling rate)] in a split-plot trial field were compared. The results showed that treatment of high seedling rate with low nitrogen rate (N2M3) were the best combination for high yield. Plant height and growth period increased with increasing nitrogen dose, but not significantly changed with increasing seedling density. The growth period under N3 was 7.0 days and 3.4 days longer than that under N2 and N1, respectively. Tiller number increased with increasing nitrogen rate and dropped with increasing seedling density. Regression analysis showed quadratic polynomial relationship among nitrogen application rate (X1), seedling density (X2) and yield (Y). The ma-ximum yield occurred at Y=8.60 t·hm-2, corresponding with X1=127.5 kg(N)·hm-2 of nitrogen rate and X2=0.48 million hills per hectare of rice seedling density, it’s yield was similar to N2M3, and it was 22.7%reduction in nitrogen rate in comparison with regular nitrogen (N3). Thus the best nitrogen application rate for early rice was 127.5-135 kg(N)·hm-2 and the best seed-ling density was 3.60 × 105-4.80 × 105 hills·hm-2. The study showed that increasing seedling rate and decreasing nitrogen rate could lay the basis of early rice cultivation for maximum yield in the study area. In summary, the time contradiction between double season rice of throwing transplanting could be solved by increasing seedlings rate and decreasing nitrogen rate in early rice fields. This benefited low environmental pollution and alleviated eutrophication of water agro-ecosystems.%本研

  14. Effect of the antioxidant ionol (BHT) on growth and development of etiolated wheat seedlings: control of apoptosis, cell division, organelle ultrastructure, and plastid differentiation.

    Science.gov (United States)

    Bakeeva, L E; Zamyatnina, V A; Shorning, B Y; Aleksandrushkina, N I; Vanyushin, B F

    2001-08-01

    Ionol (BHT), a compound having antioxidant activity, at concentrations in the range 1-50 mg/liter (0.45 x 10(-5)-2.27 x 10(-4) M), inhibits growth of etiolated wheat seedlings, changes the morphology of their organs, prolongs the coleoptile life span, and prevents the appearance of specific features of aging and apoptosis in plants. In particular, BHT prevents the age-dependent decrease in total DNA content, apoptotic internucleosomal fragmentation of nuclear DNA, appearance in the cell vacuole of specific vesicles with active mitochondria intensively producing mtDNA, and formation of heavy mitochondrial DNA rho = 1.718 g/cm3) in coleoptiles of etiolated wheat seedlings. BHT induces large structural changes in the organization of all cellular organelles (nucleus, mitochondria, plastids, Golgi apparatus, endocytoplasmic reticulum) and the formation of new unusual membrane structures in the cytoplasm. BHT distorts the division of nuclei and cells, and this results in the appearance of multi-bladed polyploid nuclei and multinuclear cells. In roots of etiolated wheat seedlings, BHT induces intensive synthesis of pigments, presumably carotenoids, and the differentiation of plastids with formation of chloro- or chromoplasts. The observed multiple effects of BHT are due to its antioxidative properties (the structural BHT analog 3,5-di-tert-butyltoluene is physiologically inert; it has no effect similar to that of BHT). Therefore, the reactive oxygen species (ROS) controlled by BHT seem to trigger apoptosis and the structural reorganization of the cytoplasm in the apoptotic cell with formation of specific vacuolar vesicles that contain active mitochondria intensively producing mtDNA. Thus, the inactivation of ROS by BHT may be responsible for the observed changes in the structure of all the mentioned cellular organelles. This corresponds to the idea that ROS control apoptosis and mitosis including formation of cell wall, and they are powerful secondary messengers that

  15. Early intestinal Bacteroides fragilis colonisation and development of asthma

    Directory of Open Access Journals (Sweden)

    Goossens Herman

    2008-09-01

    Full Text Available Abstract Background The 'hygiene hypothesis' suggests that early exposure to microbes can be protective against atopic disease. The intestinal microbial flora could operate as an important postnatal regulator of the Th1/Th2 balance. The aim of the study was to investigate the association between early intestinal colonisation and the development of asthma in the first 3 years of life. Methods In a prospective birth cohort, 117 children were classified according to the Asthma Predictive Index. A positive index included wheezing during the first three years of life combined with eczema in the child in the first years of life or with a parental history of asthma. A faecal sample was taken at the age of 3 weeks and cultured on selective media. Results Asthma Predictive Index was positive in 26/117 (22% of the children. The prevalence of colonisation with Bacteroides fragilis was higher at 3 weeks in index+ compared to index- children (64% vs. 34% p Bacteroides fragilis and Total Anaerobes counts at 3 weeks were significantly higher in children with a positive index as compared with those without. After adjusting for confounders a positive association was found between Bacteroides fragilis colonisation and Asthma Predictive Index (odds ratio: 4,4; confidence interval: 1,7 – 11,8. Conclusion Bacteroides fragilis colonisation at age 3 weeks is an early indicator of possible asthma later in life. This study could provide the means for more accurate targeting of treatment and prevention and thus more effective and better controlled modulation of the microbial milieu.

  16. Macrosomia has its roots in early placental development.

    Science.gov (United States)

    Schwartz, N; Quant, H S; Sammel, M D; Parry, S

    2014-09-01

    We sought to determine if early placental size, as measured by 3-dimensional ultrasonography, is associated with an increased risk of delivering a macrosomic or large-for-gestational age (LGA) infant. We prospectively collected 3-dimensional ultrasound volume sets of singleton pregnancies at 11-14 weeks and 18-24 weeks. Birth weights were collected from the medical records. After delivery, the ultrasound volume set were used to measure the placental volume (PV) and placental quotient (PQ = PV/gestational age), as well as the mean placental and chorionic diameters (MPD and MCD, respectively). Placental measures were analyzed as predictors of macrosomia (birth weight ≥4000 g) and LGA (birth weight ≥90th percentile). The 578 pregnancies with first trimester volumes included 44 (7.6%) macrosomic and 43 (7.4%) LGA infants. 373 subjects also had second trimester volumes available. A higher PV and PQ were both significantly associated with macrosomia and LGA in both the first and second trimesters. Second trimester MPD was significantly associated with both outcomes as well, while second trimester MCD was only associated with LGA. The above associations remained significant after adjusting for maternal demographic variables such as race, ethnicity, age and diabetes. Adjusted models yielded moderate prediction of macrosomia and LGA (AUC: 0.71-0.77). Sonographic measurement of the early placenta can identify pregnancies at greater risk of macrosomia and LGA. Macrosomia and LGA are already determined in part by early placental growth and development. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Symmetry breaking and convergent extension in early chordate development.

    Science.gov (United States)

    Schiffmann, Yoram

    2006-10-01

    The initiation of axis, polarity, cell differentiation, and gastrulation in the very early chordate development is due to the breaking of radial symmetry. It is believed that this occurs by an external signal. We suggest instead spontaneous symmetry breaking through the agency of the Turing-Child field. Increased size or decreased diffusivity, both brought about by mitotic activity, cause the spontaneous loss of stability of the homogeneous state and the evolution of the metabolic pattern during development. The polar metabolic pattern is the cause of polar gene expression, polar morphogenesis (gastrulation), and polar mitotic activity. The Turing-Child theory explains not only the spontaneous formation of the invagination in gastrulation but also the coherent cell movement observed in convergence and extension during gastrulation and neurulation. The theory is demonstrated with respect to experimental observations on the early development of fish, amphibian, and the chick. The theory can explain a multitude of experimental details. For example, it explains the splayed polar progression of reduction in the fish blastoderm. Reduction starts on that side of the blastoderm margin, which will initiate invagination several hours later. It progresses toward the blastoderm center and somewhat laterally from this future "dorsal lip". This is precisely as predicted by a Turing-Child system in a circle. And for a fish like zebrafish with a blastoderm that is slightly oval, reduction is observed to progress along the long axis of the ellipse, which is what Turing-Child theory predicts. In general the shape and the chemical nature of the experimental patterns are the same as predicted by the Turing couple (cAMP, ATP). Embryological polarity and convergent extension are based on polar eigenfunction and saddle-shaped eigenfunction, respectively.

  18. Longitudinal development of prefrontal function during early childhood.

    Science.gov (United States)

    Moriguchi, Yusuke; Hiraki, Kazuo

    2011-04-01

    This is a longitudinal study on development of prefrontal function in young children. Prefrontal areas have been observed to develop dramatically during early childhood. To elucidate this development, we gave children cognitive shifting tasks related to prefrontal function at 3 years of age (Time 1) and 4 years of age (Time 2). We then monitored developmental changes in behavioral performance and examined prefrontal activation using near infrared spectroscopy. We found that children showed better behavioral performance and significantly stronger inferior prefrontal activation at Time 2 than they did at Time 1. Moreover, we demonstrated individual differences in prefrontal activation for the same behavioral tasks. Children who performed better in tasks at Time 1 showed significant activation of the right inferior prefrontal regions at Time 1 and significant activation of the bilateral inferior prefrontal regions at Time 2. Children who showed poorer performance at Time 1 exhibited no significant inferior prefrontal activation at Time 1 but significant left inferior prefrontal activation at Time 2. These results indicate the importance of the longitudinal method to address the link between cognitive and neural development.

  19. Mechanical origins of rightward torsion in early chick brain development

    Science.gov (United States)

    Chen, Zi; Guo, Qiaohang; Dai, Eric; Taber, Larry

    2015-03-01

    During early development, the neural tube of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This torsional deformation is one of the major organ-level left-right asymmetry events in development. Previous studies suggested that bending is mainly due to differential growth, however, the mechanism for torsion remains poorly understood. Since the heart almost always loops rightwards that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is lacking, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. Moreover, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model and a 3D printed physical model are employed to help interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, and further reveals that the asymmetric development in one organ can induce the asymmetry of another developing organ through mechanics, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''. Z.C. is supported by the Society in Science - Branco Weiss fellowship, administered by ETH Zurich. L.A.T acknowledges the support from NIH Grants R01 GM075200 and R01 NS070918.

  20. Community-Wide Spatial and Temporal Discordances of Seed-Seedling Shadows in a Tropical Rainforest

    Science.gov (United States)

    Rother, Débora Cristina; Pizo, Marco Aurélio; Siqueira, Tadeu; Rodrigues, Ricardo Ribeiro; Jordano, Pedro

    2015-01-01

    Several factors decrease plant survival throughout their lifecycles. Among them, seed dispersal limitation may play a major role by resulting in highly aggregated (contagious) seed and seedling distributions entailing increased mortality. The arrival of seeds, furthermore, may not match suitable environments for seed survival and, consequently, for seedling establishment. In this study, we investigated spatio-temporal patterns of seed and seedling distribution in contrasting microhabitats (bamboo and non-bamboo stands) from the Brazilian Atlantic Forest. Spatial distribution patterns, spatial concordance between seed rain and seedling recruitment between subsequent years in two fruiting seasons (2004–2005 and 2007–2009), and the relation between seeds and seedlings with environmental factors were examined within a spatially-explicit framework. Density and species richness of both seeds and seedlings were randomly distributed in non-bamboo stands, but showed significant clustering in bamboo stands. Seed and seedling distributions showed across-year inconsistency, suggesting a marked spatial decoupling of the seed and seedling stages. Generalized linear mixed effects models indicated that only seed density and seed species richness differed between stand types while accounting for variation in soil characteristics. Our analyses provide evidence of marked recruitment limitation as a result of the interplay between biotic and abiotic factors. Because bamboo stands promote heterogeneity in the forest, they are important components of the landscape. However, at high densities, bamboos may limit recruitment for the plant community by imposing marked discordances of seed arrival and early seedling recruitment. PMID:25856393

  1. Different Ratio of Red and Blue LED Regulation Growth and Development of Cucumber Seedlings%不同红蓝配比的LED光调控黄瓜幼苗的生长

    Institute of Scientific and Technical Information of China (English)

    徐文栋; 刘晓英; 焦学磊; 徐志刚

    2015-01-01

    Red and blue light are the most important spectrum absorbed by plants. The demands quantitative of different crops for red or blue light are different. In this study, we adopted red and blue LED, the effects of different ratio of red and blue LED on growth of cucumber seedling were investigated to provide a theoretical basis and data support for cucumber seedlings to light regulation. The results showed that the ratio of red and blue LED regulated growth and development of cucumber seedlings. Except the treatment of 25%red light of R25, with decreasing of red light, the plant height increased. Stem diameter of 75%red light of R75 treatment was the thickest and chlorophyll content was the most. Leaf area of 100%blue light of R0 treatment was the largest. With the decrease of red light, fresh and dry weight of plant ifrst increased then decreased, plant fresh weight, dry weight and healthy index of R75 treatment were signiifcantly greater than those of other treatments. With blue light increased, soluble sugar content decreased. The results suggested that red and blue composited LED light regulation cucumber seedlings growth was promoted and prohibited effects of red and blue light. Under 75%red light of R75, cucumber seedlings is healthier and stronger, and accumulated more biomass. The ratio 3:1 of red and blue composited light can be used reference standard of spectrum modulation for culturing cucumber seedlings in facilities.%红光和蓝光是植物吸收的最主要光谱,不同作物对红光和蓝光光谱的需求有差异。本研究采用LED调制红蓝光的不同配比,研究了不同红蓝配比的LED光对黄瓜幼苗生长的影响,以期为设施黄瓜育苗光调控提供理论依据和数据支撑。结果显示:除红光比例为25%的R25处理外,其他处理的株高随着红光比例的减小而增大;在红光比例为75%的R75处理中,植株茎粗最大、叶绿素含量最高;100%蓝光处理的叶面积最大;随着红

  2. The role of below-ground competition during early stages of secondary succession: the case of 3-year-old Scots pine (Pinus sylvestris L.) seedlings in an abandoned grassland.

    Science.gov (United States)

    Picon-Cochard, Catherine; Coll, Lluis; Balandier, Philippe

    2006-06-01

    In abandoned or extensively managed grasslands, the mechanisms involved in pioneer tree species success are not fully explained. Resource competition among plants and microclimate modifications have been emphasised as possible mechanisms to explain variation of survivorship and growth. In this study, we evaluated a number of mechanisms that may lead to successful survival and growth of seedlings of a pioneer tree species (Pinus sylvestris) in a grass-dominated grassland. Three-year-old Scots pines were planted in an extensively managed grassland of the French Massif Central and for 2 years were either maintained in bare soil or subjected to aerial and below-ground interactions induced by grass vegetation. Soil temperatures were slightly higher in bare soil than under the grass vegetation, but not to an extent explaining pine growth differences. The tall grass canopy reduced light transmission by 77% at ground level and by 20% in the upper part of Scots pine seedlings. Grass vegetation presence also significantly decreased soil volumetric water content (Hv) and soil nitrate in spring and in summer. In these conditions, the average tree height was reduced by 5% compared to trees grown in bare soil, and plant biomass was reduced by 85%. Scots pine intrinsic water-use efficiency (A/g), measured by leaf gas-exchange, increased when Hv decreased owing to a rapid decline of stomatal conductance (g). This result was also confirmed by delta 13C analyses of needles. A summer 15N labelling of seedlings and grass vegetation confirmed the higher NO3 capture capacity of grass vegetation in comparison with Scots pine seedlings. Our results provide evidence that the seedlings' success was linked to tolerance of below-ground resource depletion (particularly water) induced by grass vegetation based on morphological and physiological plasticity as well as to resource conservation.

  3. Recent psychological explanations of infant development and scales of early mental development

    Directory of Open Access Journals (Sweden)

    Maja Zupančič

    2002-12-01

    Full Text Available This paper reviews early infant measures based on standardised scales of development – both traditional ones and those based on Piaget's sensory-motor theory – and assesses their validity in predicting later mental development. The extremely low predictive power of test scores based on these measures in infancy has provided additional support for discontinuity theories of mental development from infancy to childhood. Conversely, the constructs implicit in earlier measures have been thoroughly criticised, and the search for valid measures of infant development that would reflect a construct similar to mental abilities in childhood has begun. At the outset, research was mostly influenced by the information processing theory. Two broad measures of information processing have been shown to be the most relevant indicators of an infant's mental development, namely habituation and dishabituation. Recent mental scales, such as the Bayley Scales of Infant Development-II, thus include items that measure the efficiency of an infant's information processing. Examples of such items are presented and interpreted, as are items reflecting the development of object permanence, the only early sensory-motor measure that shows better predictive effectiveness when compared to traditional developmental test scores. Several newly-developed indicators of infants' mental development, which utilize other measures than those derived from the information-processing approach, are surveyed (understanding causal relations, joint attention behaviours, representation of number, and their possible application within the context of potential items for early mental scales is discussed. Finally, the Bayley Scales of Infant Development-II, currently one of the best measures of early development, and presently undergoing a standardisation procedure in Slovenia, is evaluated, with analyses of some items from the Mental scale presented within the text.

  4. ATLIS. Early Childhood Development and the Electronic Age.

    Science.gov (United States)

    Alexander, Nancy P.

    1994-01-01

    Describes the America Tomorrow Leadership Information Service (ATLIS) and how this information can benefit early childhood professionals. Discusses the future of telecommunications in the early childhood profession and includes a glossary of telecommunications terms. (HTH)

  5. Nuclear lamins during gametogenesis, fertilization and early development

    Science.gov (United States)

    Maul, G. G.; Schatten, G.

    1986-01-01

    The distribution of lamins (described by Gerace, 1978, as major proteins of nuclear envelope) during gametogenesis, fertilization, and early development was investigated in germ cells of a mouse (Mus musculus), an echinoderm (Lytechinus variegatus), and the surf clam (Spisula solidissima) was investigated in order to determine whether the differences detected could be correlated with differences in the function of cells in these stages of the germ cells. In order to monitor the behavior of lamins, the gametes and embryos were labeled with antibodies to lamins A, C, and B extracted from autoimmune sera of patients with scleroderma and Lupus erythematosus. Results indicated that lamin B could be identified in nuclear envelopes on only those nuclei where chromatin is attached and where RNA synthesis takes place.

  6. From universal to language-specific in early grammatical development.

    Science.gov (United States)

    Bowerman, M

    1994-10-29

    Attempts to explain children's grammatical development often assume a close initial match between units of meaning and units of form; for example, agents are said to map to sentence-subjects and actions to verbs. The meanings themselves, according to this view, are not influenced by language, but reflect children's universal non-linguistic way of understanding the world. This paper argues that, contrary to this position, meaning as it is expressed in children's early sentences is, from the beginning, organized on the basis of experience with the grammar and lexicon of a particular language. As a case in point, children learning English and Korean are shown to express meanings having to do with direct motion according to language-specific principles of semantic and grammatical structuring from the earliest stages of word combination.

  7. Women, "Star Trek," and the early development of fannish vidding

    Directory of Open Access Journals (Sweden)

    Francesca Coppa

    2008-09-01

    Full Text Available This paper argues that the practices and aesthetics of vidding were structured by the relationship of Star Trek's female fans to that particular televisual text. Star Trek fandom was the crucible within which vidding developed because Star Trek's narrative impelled female fans to take on two positions often framed as contradictory in mainstream culture: the desiring body, and the controlling voice of technology. To make a vid, to edit footage to subtext-revealing music, is to unite these positions: to put technology at the service of desire. Although the conflict between desire and control was particularly thematized in Star Trek, most famously through the divided character of Spock, the practices of vidding are now applied to other visual texts. This essay examines the early history of vidding and demonstrates, through the close reading of particular vids made for Star Trek and Quantum Leap, how vidding heals the wounds created by the displacement and fragmentation of women on television.

  8. Late Cretaceous-Early Palaeogene tectonic development of SE Asia

    Science.gov (United States)

    Morley, C. K.

    2012-10-01

    The Late Cretaceous-Early Palaeogene history of the continental core of SE Asia (Sundaland) marks the time prior to collision of India with Asia when SE Asia, from the Tethys in the west to the Palaeo-Pacific in the east, lay in the upper plate of subduction zones. In Myanmar and Sumatra, subduction was interrupted in the Aptian-Albian by a phase of arc accretion (Woyla and Mawgyi arcs) and in Java, eastern Borneo and Western Sulawesi by collision of continental fragments rifted from northern Australia. Subsequent resumption of subduction in the Myanmar-Thailand sector explains: 1) early creation of oceanic crust in the Andaman Sea in a supra-subduction zone setting ~ 95 Ma, 2) the belt of granite plutons of Late Cretaceous-Early Palaeogene age (starting ~ 88 Ma) in western Thailand and central Myanmar, and 3) amphibolite grade metamorphism between 70 and 80 Ma seen in gneissic outcrops in western and central Thailand, and 4) accretionary prism development in the Western Belt of Myanmar, until glancing collision with the NE corner of Greater India promoted ophiolite obduction, deformation and exhumation of marine sediments in the early Palaeogene. The Ranong strike-slip fault and other less well documented faults, were episodically active during the Late Cretaceous-Palaeogene time. N to NW directed subduction of the Palaeo-Pacific ocean below Southern China, Vietnam and Borneo created a major magmatic arc, associated with rift basins, metamorphic core complexes and strike-slip deformation which continued into the Late Cretaceous. The origin and timing of termination of subduction has recently been explained by collision of a large Luconia continental fragment either during the Late Cretaceous or Palaeogene. Evidence for such a collision is absent from the South China Sea well and seismic reflection record and here collision is discounted. Instead relocation of the subducting margin further west, possibly in response of back-arc extension (which created the Proto

  9. Mutations in a plastid-localized elongation factor G alter early stages of plastid development in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Hangarter Roger P

    2007-07-01

    Full Text Available Abstract Background Proper development of plastids in embryo and seedling tissues is critical for plant development. During germination, plastids develop to perform many critical functions that are necessary to establish the seedling for further growth. A growing body of work has demonstrated that components of the plastid transcription and translation machinery must be present and functional to establish the organelle upon germination. Results We have identified Arabidopsis thaliana mutants in a gene that encodes a plastid-targeted elongation factor G (SCO1 that is essential for plastid development during embryogenesis since two T-DNA insertion mutations in the coding sequence (sco1-2 and sco1-3 result in an embryo-lethal phenotype. In addition, a point mutation allele (sco1-1 and an allele with a T-DNA insertion in the promoter (sco1-4 of SCO1 display conditional seedling-lethal phenotypes. Seedlings of these alleles exhibit cotyledon and hypocotyl albinism due to improper chloroplast development, and normally die shortly after germination. However, when germinated on media supplemented with sucrose, the mutant plants can produce photosynthetically-active green leaves from the apical meristem. Conclusion The developmental stage-specific phenotype of the conditional-lethal sco1 alleles reveals differences in chloroplast formation during seedling germination compared to chloroplast differentiation in cells derived from the shoot apical meristem. Our identification of embryo-lethal mutant alleles in the Arabidopsis elongation factor G indicates that SCO1 is essential for plant growth, consistent with its predicted role in chloroplast protein translation.

  10. Diversity. Early Developments. Volume 8, Number 1, Spring 2004

    Science.gov (United States)

    Manuel, John

    2004-01-01

    What is it about cultural diversity that challenges early childhood programs? One factor is that children enter early childhood and early intervention programs from families with a wide range of values and cultural experiences. Sometimes those values and experiences differ from those of the teachers and caregivers in those programs. Another factor…

  11. Ethnic Group Differences in Early Head Start Parents Parenting Beliefs and Practices and Links to Children's Early Cognitive Development

    Science.gov (United States)

    Keels, Micere

    2009-01-01

    Data from the Early Head Start Research and Evaluation study were used to examine the extent to which several factors mediate between- and within-ethnic-group differences in parenting beliefs and behaviors, and children's early cognitive development (analysis sample of 1198 families). The findings indicate that Hispanic-, European-, and…

  12. Improving Latino Children's Early Language and Literacy Development: Key Features of Early Childhood Education within Family Literacy Programmes

    Science.gov (United States)

    Jung, Youngok; Zuniga, Stephen; Howes, Carollee; Jeon, Hyun-Joo; Parrish, Deborah; Quick, Heather; Manship, Karen; Hauser, Alison

    2016-01-01

    Noting the lack of research on how early childhood education (ECE) programmes within family literacy programmes influence Latino children's early language and literacy development, this study examined key features of ECE programmes, specifically teacher-child interactions and child engagement in language and literacy activities and how these…

  13. Ethnic Group Differences in Early Head Start Parents Parenting Beliefs and Practices and Links to Children's Early Cognitive Development

    Science.gov (United States)

    Keels, Micere

    2009-01-01

    Data from the Early Head Start Research and Evaluation study were used to examine the extent to which several factors mediate between- and within-ethnic-group differences in parenting beliefs and behaviors, and children's early cognitive development (analysis sample of 1198 families). The findings indicate that Hispanic-, European-, and…

  14. Exploring Parental Involvement in Early Years Education in China: Development and Validation of the Chinese Early Parental Involvement Scale (CEPIS)

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    Lau, Eva Yi Hung; Li, Hui; Rao, Nirmala

    2012-01-01

    This study developed and validated an instrument, the Chinese Early Parental Involvement Scale (CEPIS), that can be widely used in both local and international contexts to assess Chinese parental involvement in early childhood education. The study was carried out in two stages: (1) focus group interviews were conducted with 41 teachers and 35…

  15. Improving Latino Children's Early Language and Literacy Development: Key Features of Early Childhood Education within Family Literacy Programmes

    Science.gov (United States)

    Jung, Youngok; Zuniga, Stephen; Howes, Carollee; Jeon, Hyun-Joo; Parrish, Deborah; Quick, Heather; Manship, Karen; Hauser, Alison

    2016-01-01

    Noting the lack of research on how early childhood education (ECE) programmes within family literacy programmes influence Latino children's early language and literacy development, this study examined key features of ECE programmes, specifically teacher-child interactions and child engagement in language and literacy activities and how these…

  16. Dawn and Dusk Set States of the Circadian Oscillator in Sprouting Barley (Hordeum vulgare Seedlings.

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    Weiwei Deng

    Full Text Available The plant circadian clock is an internal timekeeper that coordinates biological processes with daily changes in the external environment. The transcript levels of clock genes, which oscillate to control circadian outputs, were examined during early seedling development in barley (Hordeum vulgare, a model for temperate cereal crops. Oscillations of clock gene transcript levels do not occur in barley seedlings grown in darkness or constant light but were observed with day-night cycles. A dark-to-light transition influenced transcript levels of some clock genes but triggered only weak oscillations of gene expression, whereas a light-to-dark transition triggered robust oscillations. Single light pulses of 6, 12 or 18 hours induced robust oscillations. The light-to-dark transition was the primary determinant of the timing of subsequent peaks of clock gene expression. After the light-to-dark transition the timing of peak transcript levels of clock gene also varied depending on the length of the preceding light pulse. Thus, a single photoperiod can trigger initiation of photoperiod-dependent circadian rhythms in barley seedlings. Photoperiod-specific rhythms of clock gene expression were observed in two week old barley plants. Changing the timing of dusk altered clock gene expression patterns within a single day, showing that alteration of circadian oscillator behaviour is amongst the most rapid molecular responses to changing photoperiod in barley. A barley EARLY FLOWERING3 mutant, which exhibits rapid photoperiod-insensitive flowering behaviour, does not establish clock rhythms in response to a single photoperiod. The data presented show that dawn and dusk cues are important signals for setting the state of the circadian oscillator during early development of barley and that the circadian oscillator of barley exhibits photoperiod-dependent oscillation states.

  17. Canonical Sonic Hedgehog Signaling in Early Lung Development

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    Hugo Fernandes-Silva

    2017-03-01

    Full Text Available The canonical hedgehog (HH signaling pathway is of major importance during embryonic development. HH is a key regulatory morphogen of numerous cellular processes, namely, cell growth and survival, differentiation, migration, and tissue polarity. Overall, it is able to trigger tissue-specific responses that, ultimately, contribute to the formation of a fully functional organism. Of all three HH proteins, Sonic Hedgehog (SHH plays an essential role during lung development. In fact, abnormal levels of this secreted protein lead to severe foregut defects and lung hypoplasia. Canonical SHH signal transduction relies on the presence of transmembrane receptors, such as Patched1 and Smoothened, accessory proteins, as Hedgehog-interacting protein 1, and intracellular effector proteins, like GLI transcription factors. Altogether, this complex signaling machinery contributes to conveying SHH response. Pulmonary morphogenesis is deeply dependent on SHH and on its molecular interactions with other signaling pathways. In this review, the role of SHH in early stages of lung development, specifically in lung specification, primary bud formation, and branching morphogenesis is thoroughly reviewed.

  18. Early influences and childhood development. Does helicobacter play a role?

    Science.gov (United States)

    Lee, Adrian

    2007-11-01

    In the late 1960s, Rene Dubos showed that a variety of nutritional stress in utero or in early infancy could have dramatic impact on childhood development that was irreversible. This included detectable changes in the brain. Since that time, iron deficiency anemia (IDA) has been identified as one of the major nutritional stresses that leads to permanent behavioral changes in both experimental animals and humans resulting in poorer cognitive, motor, and social-emotional function. It has been proposed that these changes play an important part in the inter-generational transmission of poverty. More recently, it is becoming clear that Helicobacter pylori causes IDA in populations on an iron-limiting diet. The main thesis of this article is that H. pylori infection may indeed have an impact on childhood development and that much more research is needed in this area as intervention via immunization or antimicrobial therapy in populations in the developing world may have major positive benefits via cure of IDA and prevention of brain damage in the young.

  19. Structural and Maturational Covariance in Early Childhood Brain Development.

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    Geng, Xiujuan; Li, Gang; Lu, Zhaohua; Gao, Wei; Wang, Li; Shen, Dinggang; Zhu, Hongtu; Gilmore, John H

    2017-03-01

    Brain structural covariance networks (SCNs) composed of regions with correlated variation are altered in neuropsychiatric disease and change with age. Little is known about the development of SCNs in early childhood, a period of rapid cortical growth. We investigated the development of structural and maturational covariance networks, including default, dorsal attention, primary visual and sensorimotor networks in a longitudinal population of 118 children after birth to 2 years old and compared them with intrinsic functional connectivity networks. We found that structural covariance of all networks exhibit strong correlations mostly limited to their seed regions. By Age 2, default and dorsal attention structural networks are much less distributed compared with their functional maps. The maturational covariance maps, however, revealed significant couplings in rates of change between distributed regions, which partially recapitulate their functional networks. The structural and maturational covariance of the primary visual and sensorimotor networks shows similar patterns to the corresponding functional networks. Results indicate that functional networks are in place prior to structural networks, that correlated structural patterns in adult may arise in part from coordinated cortical maturation, and that regional co-activation in functional networks may guide and refine the maturation of SCNs over childhood development. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. The Early Stages of Heart Development: Insights from Chicken Embryos

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    Johannes G. Wittig

    2016-04-01

    Full Text Available The heart is the first functioning organ in the developing embryo and a detailed understanding of the molecular and cellular mechanisms involved in its formation provides insights into congenital malformations affecting its function and therefore the survival of the organism. Because many developmental mechanisms are highly conserved, it is possible to extrapolate from observations made in invertebrate and vertebrate model organisms to humans. This review will highlight the contributions made through studying heart development in avian embryos, particularly the chicken. The major advantage of chick embryos is their accessibility for surgical manipulation and functional interference approaches, both gain- and loss-of-function. In addition to experiments performed in ovo, the dissection of tissues for ex vivo culture, genomic, or biochemical approaches is straightforward. Furthermore, embryos can be cultured for time-lapse imaging, which enables tracking of fluorescently labeled cells and detailed analysis of tissue morphogenesis. Owing to these features, investigations in chick embryos have led to important discoveries, often complementing genetic studies in mice and zebrafish. As well as including some historical aspects, we cover here some of the crucial advances made in understanding early heart development using the chicken model.

  1. Effects of Uniconazole on Root Growth and Development of Cucumber Plug Seedling%烯效唑对黄瓜穴盘苗根系发育的影响

    Institute of Scientific and Technical Information of China (English)

    蒋玉香

    2014-01-01

    Using cucumber (Cucumis sativus L.﹚ Ludi NO.2 as the experimental material, effects of different concentration u-niconazole on root growth and development of cucumber plug seedling were studied. Results showed that under the treatments of different concentration uniconazole, the length of taproot of cucumber plug seedlings was reduced. The accumulation of dry matter, root-shoot ratio, root activity, nitrate reductase and proline content were increased. 1μL/L uniconazole comprehensive treatment had the best effect.%以黄瓜(Cucumis sativus L.)露地2号为试验材料,研究不同浓度烯效唑对黄瓜穴盘苗根系生长发育的影响。结果表明,不同浓度烯效唑处理黄瓜穴盘苗,降低了主根长度,促进干物质积累,提高根冠比,增加根系活力,提高硝酸还原酶活性和脯氨酸含量,其中以1μL/L烯效唑处理综合效果最佳。

  2. Impact of Early Postnatal Androgen Exposure on Voice Development

    Science.gov (United States)

    Grisa, Leila; Leonel, Maria L.; Gonçalves, Maria I. R.; Pletsch, Francisco; Sade, Elis R.; Custódio, Gislaine; Zagonel, Ivete P. S.; Longui, Carlos A.; Figueiredo, Bonald C.

    2012-01-01

    Background The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood. Methods The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels. Results Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz. Conclusions Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors. PMID:23284635

  3. Impact of early postnatal androgen exposure on voice development.

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    Leila Grisa

    Full Text Available BACKGROUND: The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT in childhood. METHODS: The long-term effects of androgen exposure on the fundamental vocal frequency (F0, vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years and 10 adolescent (13.6 to 17.8 years female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels. RESULTS: Of the 19 subjects, 17 (89% had been diagnosed with ACT before 4 years of age, 1 (5% at 8.16 years, and 1 (5% at 10.75 years. Androgen exposure (2 to 30 months was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19 of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz. CONCLUSIONS: Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.

  4. Wood formation in Abies balsamea seedlings subjected to artificial defoliation.

    Science.gov (United States)

    Rossi, Sergio; Simard, Sonia; Deslauriers, Annie; Morin, Hubert

    2009-04-01

    We determined the cambial sensitivity and quantified the anatomical differences in xylem of Abies balsamea (L.) Mill. seedlings subjected to artificial defoliation to simulate spruce budworm feeding. Defoliation was performed by removing two-thirds of needles of all current-year shoots for up to four consecutive growth cycles to account for inter- and intra-annual xylem formation. In Experiment 1, xylem development was studied from May to October 2005 in seedlings defoliated at the end of June. In Experiment 2, anatomical features of the xylem were measured along the tree rings formed in 2005 and 2006 during the four cycles of growth and defoliation. Control and defoliated seedlings showed similar patterns of cambial activity and timing of xylem differentiation, although fewer enlarging cells were observed in August to September in defoliated seedlings. Tree-ring widths were similar in control and defoliated seedlings, with thinner rings produced in the greenhouse in winter. No effect of defoliation on cell lumen area was observed, and effects on radial cell diameter and wall thickness were found only occasionally. The results indicate that the A. balsamea seedlings produced all the resources required to maintain stem growth during the four cycles of defoliation.

  5. Origins and early development of human body knowledge.

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    Slaughter, Virginia; Heron, Michelle

    2004-01-01

    As a knowable object, the human body is highly complex. Evidence from several converging lines of research, including psychological studies, neuroimaging and clinical neuropsychology, indicates that human body knowledge is widely distributed in the adult brain, and is instantiated in at least three partially independent levels of representation. Sensorimotor body knowledge is responsible for on-line control and movement of one's own body and may also contribute to the perception of others' moving bodies; visuo-spatial body knowledge specifies detailed structural descriptions of the spatial attributes of the human body; and lexical-semantic body knowledge contains language-based knowledge about the human body. In the first chapter of this Monograph, we outline the evidence for these three hypothesized levels of human body knowledge, then review relevant literature on infants' and young children's human body knowledge in terms of the three-level framework. In Chapters II and III, we report two complimentary series of studies that specifically investigate the emergence of visuo-spatial body knowledge in infancy. Our technique is to compare infants'responses to typical and scrambled human bodies, in order to evaluate when and how infants acquire knowledge about the canonical spatial layout of the human body. Data from a series of visual habituation studies indicate that infants first discriminate scrambled from typical human body picture sat 15 to 18 months of age. Data from object examination studies similarly indicate that infants are sensitive to violations of three-dimensional human body stimuli starting at 15-18 months of age. The overall pattern of data supports several conclusions about the early development of human body knowledge: (a) detailed visuo-spatial knowledge about the human body is first evident in the second year of life, (b) visuo-spatial knowledge of human faces and human bodies are at least partially independent in infancy and (c) infants' initial

  6. Drugs in early clinical development for the treatment of osteosarcoma.

    Science.gov (United States)

    Heymann, Marie-Françoise; Brown, Hannah K; Heymann, Dominique

    2016-11-01

    Osteosarcomas are the main malignant primary bone tumours found in children and young adults. Conventional treatment is based on diagnosis and resection surgery, combined with polychemotherapy. This is a protocol that was established in the 1970s. Unfortunately, this therapeutic approach has reached a plateau of efficacy and the patient survival rate has not improved in the last four decades. New therapeutic approaches are thus required to improve the prognosis for osteosarcoma patients. Areas covered: From the databases available and published scientific literature, the present review gives an overview of the drugs currently in early clinical development for the treatment of osteosarcoma. For each drug, a short description is given of the relevant scientific data supporting its development. Expert opinion: Multidrug targeted approaches are set to emerge, given the heterogeneity of osteosarcoma subtypes and the multitude of therapeutic responses. The key role played by the microenvironment in the disease increases the number of therapeutic targets (such as macrophages or osteoclasts), as well as the master proteins that control cell proliferation or cell death. Ongoing phase I/II trials are important steps, not only for identifying new therapies with greater safety and efficacy, but also for better defining the role played by the microenvironment in the pathogenesis of osteosarcoma.

  7. Early phonetic and lexical development: a productivity approach.

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    McCune, L; Vihman, M M

    2001-06-01

    Researchers frequently examine the development of the single-word lexicon in the absence of phonetic data. Yet a large body of literature demonstrates relationships between the phonetics of babble and early speech, and it is clear that production skill is essential for establishing a lexicon. This study uses longitudinal productivity criteria to establish children's phonetic skill. Twenty children were followed from age 9 to 16 months, and their level of consistency of vocal patterns was examined in relation to their lexical production, providing a relatively large-sample demonstration of phonetic/lexical relationships at the transition to language. Number of specific consonants produced consistently across the months of observation predicted referential lexical use at 16 months, whereas the transition to reference itself signaled the onset of a sharp increase in numbers of different words produced in a session. The earliest referential speakers exhibited prior consistency in the production of [p/b], which also predominated in their words. Prior use of at least two supraglottal consonants characterized the referential group. Children varied in the specific consonants they produced consistently, and these same consonants, varying according to individual child repertoire, characterized nearly all consonant-based words produced by each child in both of the final 2 months of observation. These findings are interpreted in relation to the children's contemporaneous development of representational ability and pragmatic skill.

  8. Discovery and early development of non-suppressed ion chromatography.

    Science.gov (United States)

    Fritz, James S; Gjerde, Douglas T

    2010-08-01

    This year marks the 30th anniversary of the publication of Non-Suppressed Ion Chromatography, which is a method for the rapid separation of anions with on-line conductimetric detection. In this method, the separation column is connected directly to the conductimetric detector. This single-column method is a simpler technique than the original suppressed ion chromatography method, which requires a large suppressor column to reduce the background conductance. In the new method, the background signal is reduced to a manageable level simply by using an ion-exchange separation column of low exchange capacity that lowers the eluent concentration needed for separation. The eluent ion used for separation is chosen based on having large, bulky structure, which lowers the equivalent conductance and facilitates detection of the sample anions. This is a personal account of the initial discovery and early development of non-suppressed ion chromatography. The circumstances for the discovery are recounted by the two authors. Methods are described for determination of anions, cations with indirect detection, and techniques for increasing detection sensitivity. A fundamental equation for the prediction of ion chromatography detector response is given, and the development of several types of detection schemes for ion chromatography is discussed. Finally, the impact of non-suppressed ion chromatography is discussed together with comments on the discovery process.

  9. Involvement of Notch signaling in early chick ovarian follicle development.

    Science.gov (United States)

    Li, Jun; Zhao, Dan; Guo, Changquan; Li, Jian; Mi, Yuling; Zhang, Caiqiao

    2016-01-01

    The formation of primordial follicles is a crucial process in the establishment of follicle pools required for the female's reproductive life span. For laying hens, ample follicles are a prerequisite for high laying performance. Notch signaling plays critical roles in germ cell cysts breakdown and in the formation of primordial follicles. Here, we investigated the role of Notch signaling in the ovarian development of post-hatch chicks. Results showed that around post-hatch day 4 (H4), the germ cell cysts broke apart, oocytes became surrounded by squamous pregranulosa cells, and the primordial follicles were then formed. Subsequently, we detected the expression of Notch signaling-related genes including Notch receptors (Notch1, 2), ligands (Jag1, 2 and Dll1, 4), and target genes (Hes1, Hey1). These genes all showed expression at H4 and some of these genes were up-regulated during primordial follicle formation. To evaluate the Notch signaling requirement for early follicular development, we adopted an in vitro ovary culture system. Suppression of Notch signaling by γ-secretase inhibitor induced a decrease of primordial follicles and an increase of germ cells in cysts. Attenuating Notch signaling also inhibited the phosphatidylinositol 3-kinase/protein kinase B pathways and suppressed cadherin expression. These results suggest that Notch signaling is endowed with an indispensable role in primordial follicle formation in post-hatch chicks.

  10. Influence of Different Sowing Time on Growth and Development of Cucumber Seedling and Seed Yield%不同播种期对黄瓜幼苗生长发育及 制种产量的影响

    Institute of Scientific and Technical Information of China (English)

    李光; 马德华; 杨森

    2001-01-01

    Influence of sowing date on cucumber seed production in spring was studied.Seedling growth and seed yield were closely related to sowing date in open field cucumber seed production.Seedling emergence was faster,emergence rate was higher,the length of cotyled on and lower hypocotyls was longer.Different sowing date has much influence on cucumber seed yield composite factors.So wing too early or too late,fruit number per-pant is less than that of normal sowing plant.Seed number per fruit is evide ntly less than that of normal sowing plant,the thousand grain weight of seeds was getting lower when the sowing date pos tponed.It can be concluded that the date in middle and southern part of Shandong for open field cucumber seed production in spring is between the end of March and April 5th.%研究了播种期对黄瓜幼苗生长发育和制种产量的影响。结果表明,早春随着播种期的推迟,种子出土的速度加快,幼苗下胚轴的长度明显增长,子叶纵向长度也有一定变化。播种期不同,单株瓜条数、单瓜内种子粒数均明显少于正常播期;种子千粒重随着播种时间的推迟,逐渐降低。

  11. Early

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    Kamel Abd Elaziz Mohamed

    2014-04-01

    Conclusion: Early PDT is recommended for patients who require prolonged tracheal intubation in the ICU as outcomes like the duration of mechanical ventilation length of ICU stay and hospital stay were significantly shorter in early tracheostomy.

  12. Efeito do recipiente e ambiente de cultivo sobre o desenvolvimento de mudas de mamoeiro cv. Sunrise Solo Effect of container and environment on the development of papaya seedlings cv. Sunrise Solo

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    José Ribamar Gusmão Araujo

    2006-12-01

    Full Text Available O presente trabalho teve como objetivo avaliar os efeitos de três recipientes e três condições ambientais no desenvolvimento de mudas de mamoeiro (Carica papaya L. Cv. Sunrise Solo, nas condições de clima tropical da Ilha de São Luís - MA. Os recipientes utilizados foram saco de polietileno preto nas dimensões de 20 x 32 cm e 15 x 20 cm e bandeja de poliestireno de 72 células e como ambientes foram utilizados túnel de plástico, viveiro-telado de sombrite com 50% de sombreamento e a céu aberto. Na avaliação dos caracteres biométricos, foram mensurados a altura das plantas, o diâmetro do caule e o número de folhas. No período de 14-06-2004 a 21-07-2004, foram monitoradas a precipitação, a temperatura e a umidade relativa do ar, com o auxílio de psicrômetros de ventilação natural, em cada um dos ambientes. De acordo com os resultados, concluiu-se que as mudas de mamoeiro produzidas em recipiente de sacos de polietileno 20 x 32 cm foram superiores em todos os caracteres analisados; o recipiente de bandeja de poliestireno mostrou-se inadequado para a produção de mudas; aos 45 dias após a semeadura, o ambiente a céu aberto, mostrou-se mais propício para o desenvolvimento adequado das mudas. Aos 60 dias, as mudas cultivadas sob viveiro telado apresentaram crescimento excessivo e estiolamento.The present work aimed to evaluate the effect of three containers and three environments of cropping on the development of papaya seedlings (Carica papaya L. Cv. Sunrise Solo, at the tropical climate of São Luis Island, State of Maranhão, Brazil. The used containers were black polyethylene bags of 20 x 32 cm and 15 x 20 cm and polystyrene trays of 72 cells and as environment conditions were used plastic house, black-screen house of 50% sunlight and open sky. The data taken and evaluated were plant height, diameter of stem, and leaf number. In the period of June 14th to July 21st 2004 were monitored precipitation, temperature and

  13. Volume of polyethylene bags for development of papaya seedlings in protected environments Volumes de sacolas de polietileno no desenvolvimento de mudas de mamoeiro em ambientes protegidos

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    Tatiane A. C. Faria

    2013-02-01

    Full Text Available The objective of this study was to test container of polyethylene bags and protected environments on the papaya seedlings production, from May to August of 2008, in Aquidauana state of Mato Grosso do Sul (MS, Brazil. Five bags of polyethylene were used: 7.5 cm x 11.5 cm, 205.9 cm³; 8.4 cm x 10.6 cm, 238.1cm³; 10.0 cm x 16.5 cm, 525.2 cm³; 12.0 cm x 12.0 cm, 550.0 cm³ and 15.0 cm x 21.5 cm, 1539.8 cm³. These containers were placed in three protected environments: greenhouse; screened nursery with Sombrite® and screened nursery with Aluminet®. Because there is no replication of growing environment, each one was considered an experiment. For each cultivation environment, it was adopted a completely randomized design with eight replications of two plants each. Initially, data were submitted to analysis of individual variance of the container (for each cultivation environment, then performing the evaluation of the residual mean squares and the combined analysis of these environments for comparison of protected environments. The greenhouse and nursery with thermal reflector screen produced the best seedlings. The bags of 15.0 x 21.5 cm produced the best papaya seedlings. The Dickson Quality Index pointed the nursery with screen of thermal reflector as the environment that produced the most vigorous seedlings, when using the best container.O objetivo deste trabalho foi testar sacos de polietileno e ambientes protegidos na produção de mudas de mamoeiro, de maio a agosto de 2008, em Aquidauana -MS. Foram utilizadas cinco dimensões de sacos de polietileno: 7,5 cm x 11,5 cm, 205,9 cm³; 8,4 cm x 10,6 cm, 238,1 cm³; 10,0 cm x 16,5 cm, 525,2 cm³; 12,0 cm x 12,0 cm, 550,0 cm³, e 15,0 cm x 21,5 cm, 1.539,8 cm³. Estes recipientes foram acomodados em três ambientes protegidos: estufa agrícola; viveiro telado com Sombrite® e viveiro telado com Aluminet®. Por não haver repetição do ambiente de cultivo, cada um foi considerado um experimento

  14. Early, middle, and late Miocene basin development, California

    Energy Technology Data Exchange (ETDEWEB)

    Bachman, S.B.

    1988-03-01

    Contrary to earlier models of progressive basin development related to northward migration of the Mendocino triple junction, it can now be documented that the major basins of coastal California developed at about the same time in the late Oligocene to early Miocene. This basin development is marked by rapid deepening of basin floors, subsequent changes in depositional facies from nonmarine and shallow marine to deep marine, and widespread volcanism dated at 23-20 Ma. The coastal basins likely formed by rifting and subsidence linked to the proximity of the Farallon-pacific spreading ridge and the subduction of hot young oceanic crust, but cannot be correlated to any existing models of triple junction migration. Indeed, strike-slip restored positions of the coastal basins at their inception indicate that the basins were spread out over about 800 km of the southern coast of California. The Miocene basins were likely larger than the present coastal basins, although their configurations are obscured by late Neogene faulting and erosion. It is likely, however, that paleohighs separated at least some of the margin into proximal and distal basins. With local exceptions, structuring in the Miocene basins was primarily extensional, with widespread strike-slip and thrust tectonics restricted mainly to latest Miocene and younger events. Plate reconstructions suggest several hundred kilometers of transform motion occurred along the California margin during the Miocene, but there is only limited evidence of this movement in the known history of either the basins or the major faults of California. Sedimentation during the Miocene was controlled by both oceanic conditions (biogenic component) and the relative abundance of clastic input. The clastic input was controlled by a combination of proximal vs distal basinal positions, eustatic sea level changes, and local tectonics.

  15. Early childhood development interventions and cognitive development of young children in rural Vietnam.

    Science.gov (United States)

    Watanabe, Koichiro; Flores, Rafael; Fujiwara, Junko; Tran, Lien Thi Huong

    2005-08-01

    Little is known about the long-term benefits of interventions that aim to promote early childhood development programs. The goal of this research was to determine whether an early childhood development intervention added to a nutrition intervention during preschool ages had lasting effects on the cognitive development of school-age children in communes of Thanh Hoa province in rural Vietnam. The study focused on a total of 313 children aged 6.5-8.5 y (grades 1 and 2 in primary school) in 2 communes that were exposed to nutrition intervention or nutrition and early childhood development (ECD) intervention from 1999 to 2003. Measurements of height and cognitive test scores (Raven's Progressive Matrices Test) were collected from the children; household characteristics were determined by interviews with mothers. Longitudinal analysis was performed by integrating the data with that collected from the same children in past surveys. Significant effects of the ECD intervention compared with the nutrition intervention were detected. The beneficial effect of ECD intervention on the cognitive test scores was large for the most nutritionally challenged children whose height-for-age Z-scores declined or remained in the stunted range. The findings help provide useful insights into the development of an effective integrated model of ECD and nutrition intervention for children in rural Vietnam.

  16. Pathogenicity of P. terrestris on Maize Seedlings

    Directory of Open Access Journals (Sweden)

    Jelena Lević

    2012-01-01

    Full Text Available Pathogenicity of P. terrestris was determined by the Knop’s medium slants method intest tubes. Isolates originated from the roots of maize (Zea mays L., barley (Hordeum vulgareL., Johnson grass (Sorghum halepense Pers., sorghum (Sorghum bicolour (L. Moench., garlic(Allium sativum L., onion (Allium cepa L., barnyard millet (Echinochloa crus-galli (L. P.Beauv.and green foxtail (Setaria viridis (L. P.B.. A fragment of a fungal colony, cultivated on PDA,was placed on the bottom of Knop’s medium slant in each test tube and then steriliseda maize seed was placed 2 cm away from the inoculum. After 21-day inoculation of seeds,the intensity of the development of symptoms on maize seedlings was estimated. The reddishor dark pigment on the root, mesocotyl and/or coleoptyl of seedlings was an indicatorfor the infection by the fungus under in vitro conditions. Based on the pathogenicity test,the isolates were classified into the following three groups: slightly (3 isolates, moderately(6 isolates and very pathogenic (6 isolates to maize seedlings. The obtained results showthat P. terrestris, originating from different hosts, can be a maize pathogen. These resultscan explain the high frequency and high incidence of this fungus on maize roots in Serbia.

  17. [Early Intervention and Cognitive Development: A Longitudinal Study with Psychologically Stressed Mother-Child-Dyad during Early Childhood].

    Science.gov (United States)

    Zwönitzer, Annabel; Ziegenhain, Ute; Bovenschen, Ina; Pillhofer, Melanie; Spangler, Gottfried; Gerlach, Jennifer; Gabler, Sandra; Kindler, Heinz; Fegert, Jörg M; Künster, Anne Katrin

    2016-01-01

    Early intervention programs aiming at developing parents’ relationship and parenting skills and supporting young families have become increasingly established in Germany throughout the last decade. The present longitudinal study analyzed 53 children and their mothers receiving early intervention due to their psychosocially highly challenging life situations and personal circumstances. The children were examined at birth and at an age of twelve months as well as between ages two and four. The results revealed that the child’s cognitive development could be predicted by both maternal sensitivity and mother’s psychosocial stress. However, the amount, type, and intensity of early intervention did not have any effect on the child’s development. In terms of the effectiveness of early interventions the results implicate that interventions seems to be offered in an unspecific manner and does not contribute to an improvement of the child’s developmental status.

  18. Wealth Gradients in Early Childhood Cognitive Development in Five Latin American Countries

    OpenAIRE

    Schady, Norbert Rüdiger; Behrman, Jere R.; Araujo, María Caridad; Azuero, Rodrigo; Bernal, Raquel; Bravo, David; López Bóo, Florencia; Macours, Karen; Marshall, Daniela; Paxson, Christina H.; Vakis, Renos

    2014-01-01

    Research from the United States shows that gaps in early cognitive and noncognitive abilities appear early in the life cycle. Little is known about this important question for developing countries. This paper provides new evidence of sharp differences in cognitive development by socioeconomic status in early childhood for five Latin American countries. To help with comparability, the paper...

  19. The Development of Early Childhood Teachers' Language Knowledge in Different Educational Tracks

    Science.gov (United States)

    Strohmer, Janina; Mischo, Christoph

    2015-01-01

    Early childhood teachers should have extensive knowledge about language and language development, because these facets of professional knowledge are considered as important requirements for fostering language development in early childhood education settings. It is assumed that early childhood teachers acquire this knowledge during pre-service…

  20. Development of SED Camera for Quasars in Early Universe (SQUEAN)

    CERN Document Server

    Kim, Sanghyuk; Lee, Hye-In; Park, Woojin; Ji, Tae-Geun; Hyun, Minhee; Choi, Changsu; Im, Myungshin; Pak, Soojong

    2016-01-01

    We describe the characteristics and performance of a camera system, Spectral energy distribution Camera for Quasars in Early Universe (SQUEAN). It was developed to measure SEDs of high redshift quasar candidates (z $\\gtrsim$ 5) and other targets, e.g., young stellar objects, supernovae, and gamma-ray bursts, and to trace the time variability of SEDs of objects such as active galactic nuclei (AGNs). SQUEAN consists of an on-axis focal plane camera module, an auto-guiding system, and mechanical supporting structures. The science camera module is composed of a focal reducer, a customizable filter wheel, and a CCD camera on the focal plane. The filter wheel uses filter cartridges that can house filters with different shapes and sizes, enabling the filter wheel to hold twenty filters of 50 mm $\\times$ 50 mm size, ten filters of 86 mm $\\times$ 86 mm size, or many other combinations. The initial filter mask was applied to calibrate the filter wheel with high accuracy and we verified that the filter position is repea...

  1. Novel INHAT repressor (NIR) is required for early lymphocyte development.

    Science.gov (United States)

    Ma, Chi A; Pusso, Antonia; Wu, Liming; Zhao, Yongge; Hoffmann, Victoria; Notarangelo, Luigi D; Fowlkes, B J; Jain, Ashish

    2014-09-23

    Novel inhibitor of histone acetyltransferase repressor (NIR) is a transcriptional corepressor with inhibitor of histone acetyltransferase activity and is a potent suppressor of p53. Although NIR deficiency in mice leads to early embryonic lethality, lymphoid-restricted deletion resulted in the absence of double-positive CD4(+)CD8(+) thymocytes, whereas bone-marrow-derived B cells were arrested at the B220(+)CD19(-) pro-B-cell stage. V(D)J recombination was preserved in NIR-deficient DN3 double-negative thymocytes, suggesting that NIR does not affect p53 function in response to physiologic DNA breaks. Nevertheless, the combined deficiency of NIR and p53 provided rescue of DN3L double-negative thymocytes and their further differentiation to double- and single-positive thymocytes, whereas B cells in the marrow further developed to the B220(+)CD19(+) pro-B-cell stage. Our results show that NIR cooperate with p53 to impose checkpoint for the generation of mature B and T lymphocytes.

  2. Early experiences in developing and managing the neuroscience gateway

    Science.gov (United States)

    Sivagnanam, Subhashini; Majumdar, Amit; Yoshimoto, Kenneth; Astakhov, Vadim; Bandrowski, Anita; Martone, MaryAnn; Carnevale, Nicholas. T.

    2015-01-01

    SUMMARY The last few decades have seen the emergence of computational neuroscience as a mature field where researchers are interested in modeling complex and large neuronal systems and require access to high performance computing machines and associated cyber infrastructure to manage computational workflow and data. The neuronal simulation tools, used in this research field, are also implemented for parallel computers and suitable for high performance computing machines. But using these tools on complex high performance computing machines remains a challenge because of issues with acquiring computer time on these machines located at national supercomputer centers, dealing with complex user interface of these machines, dealing with data management and retrieval. The Neuroscience Gateway is being developed to alleviate and/or hide these barriers to entry for computational neuroscientists. It hides or eliminates, from the point of view of the users, all the administrative and technical barriers and makes parallel neuronal simulation tools easily available and accessible on complex high performance computing machines. It handles the running of jobs and data management and retrieval. This paper shares the early experiences in bringing up this gateway and describes the software architecture it is based on, how it is implemented, and how users can use this for computational neuroscience research using high performance computing at the back end. We also look at parallel scaling of some publicly available neuronal models and analyze the recent usage data of the neuroscience gateway. PMID:26523124

  3. Development of SED Camera for Quasars in Early Universe (SQUEAN)

    Science.gov (United States)

    Kim, Sanghyuk; Jeon, Yiseul; Lee, Hye-In; Park, Woojin; Ji, Tae-Geun; Hyun, Minhee; Choi, Changsu; Im, Myungshin; Pak, Soojong

    2016-11-01

    We describe the characteristics and performance of a camera system, Spectral energy distribution Camera for Quasars in Early Universe (SQUEAN). It was developed to measure SEDs of high-redshift quasar candidates (z ≳ 5) and other targets, e.g., young stellar objects, supernovae, and gamma-ray bursts, and to trace the time variability of SEDs of objects such as active galactic nuclei (AGNs). SQUEAN consists of an on-axis focal plane camera module, an autoguiding system, and mechanical supporting structures. The science camera module is composed of a focal reducer, a customizable filter wheel, and a CCD camera on the focal plane. The filter wheel uses filter cartridges that can house filters with different shapes and sizes, enabling the filter wheel to hold 20 filters of 50 mm × 50 mm size, 10 filters of 86 mm × 86 mm size, or many other combinations. The initial filter mask was applied to calibrate the filter wheel with high accuracy, and we verified that the filter position is repeatable at much less than one pixel accuracy. We installed and tested 50 nm medium bandwidth filters of 600–1050 nm and other filters at the commissioning observation in 2015 February. We found that SQUEAN can reach limiting magnitudes of 23.3–25.3 AB mag at 5σ in a one-hour total integration time.

  4. Early embryonic development and transplantation in tree shrews.

    Science.gov (United States)

    Yan, Lan-Zhen; Sun, Bin; Lyu, Long-Bao; Ma, Yu-Hua; Chen, Jia-Qi; Lin, Qing; Zheng, Ping; Zhao, Xu-Dong

    2016-07-18

    As a novel experimental animal model, tree shrews have received increasing attention in recent years. Despite this, little is known in regards to the time phases of their embryonic development. In this study, surveillance systems were used to record the behavior and timing of copulations; embryos at different post-copulation stages were collected and cultured in vitro; and the developmental characteristics of both early-stage and in vitro cultured embryos were determined. A total of 163 females were collected following effective copulation, and 150 were used in either unilateral or bilateral oviduct embryo collections, with 307 embryos from 111 females obtained (conception rate=74%). Among them, 237 embryos were collected from 78 females, bilaterally, i.e., the average embryo number per female was 3.04; 172 fertilized eggs collected from 55 females, bilaterally, were cultured for 24-108 h in vitro for developmental observations; finally, 65 embryos from 23 bilateral cases and 70 embryos from 33 unilateral cases were used in embryo transplantation.

  5. Early environment and neurobehavioral development predict adult temperament clusters.

    Directory of Open Access Journals (Sweden)

    Eliza Congdon

    Full Text Available BACKGROUND: Investigation of the environmental influences on human behavioral phenotypes is important for our understanding of the causation of psychiatric disorders. However, there are complexities associated with the assessment of environmental influences on behavior. METHODS/PRINCIPAL FINDINGS: We conducted a series of analyses using a prospective, longitudinal study of a nationally representative birth cohort from Finland (the Northern Finland 1966 Birth Cohort. Participants included a total of 3,761 male and female cohort members who were living in Finland at the age of 16 years and who had complete temperament scores. Our initial analyses (Wessman et al., in press provide evidence in support of four stable and robust temperament clusters. Using these temperament clusters, as well as independent temperament dimensions for comparison, we conducted a data-driven analysis to assess the influence of a broad set of life course measures, assessed pre-natally, in infancy, and during adolescence, on adult temperament. RESULTS: Measures of early environment, neurobehavioral development, and adolescent behavior significantly predict adult temperament, classified by both cluster membership and temperament dimensions. Specifically, our results suggest that a relatively consistent set of life course measures are associated with adult temperament profiles, including maternal education, characteristics of the family's location and residence, adolescent academic performance, and adolescent smoking. CONCLUSIONS: Our finding that a consistent set of life course measures predict temperament clusters indicate that these clusters represent distinct developmental temperament trajectories and that information about a subset of life course measures has implications for adult health outcomes.

  6. Stage-specific proteome signatures in early bovine embryo development.

    Science.gov (United States)

    Deutsch, Daniela R; Fröhlich, Thomas; Otte, Kathrin A; Beck, Andrea; Habermann, Felix A; Wolf, Eckhard; Arnold, Georg J

    2014-10-03

    Development of early embryonic stages before activation of the embryonic genome depends on sufficiently stored products of the maternal genome, adequate recruitment and degradation of mRNAs, as well as activation, deactivation, and relocation of proteins. By application of an isobaric tagging for relative and absolute quantification (iTRAQ)-based approach, the proteomes of bovine embryos at the zygote and 2-cell and 4-cell stage with MII oocytes as a reference were quantitatively analyzed. Of 1072 quantified proteins, 87 differed significantly in abundance between the four stages. The proteomes of 2-cell and 4-cell embryos differed most from the reference MII oocyte, and a considerable fraction of proteins continuously increased in abundance during the stages analyzed, despite a strongly attenuated rate of translation reported for this period. Bioinformatic analysis revealed particularly interesting proteins involved in the p53 pathway, lipid metabolism, and mitosis. Verification of iTRAQ results by targeted SRM (selected reaction monitoring) analysis revealed excellent agreement for all five proteins analyzed. By principal component analysis, SRM quantifications comprising a panel of only five proteins were shown to discriminate between all four developmental stages analyzed here. For future experiments, an expanded SRM protein panel will provide the potential to detect developmental disturbances with high sensitivity and enable first insights into the underlying molecular pathways.

  7. Desarrollo vegetativo de patrones cítricos cultivados en condiciones de invernadero bajo dos sistemas de riego Vegetative development of citrus seedlings cultivated at greenhouse conditions and submitted to two irrigations systems

    Directory of Open Access Journals (Sweden)

    Gilmar Schäfer

    2006-08-01

    Full Text Available En el presente estudio se evaluó el desarrollo vegetativo de patrones cítricos cultivados en invernadero bajo dos sistemas de riego. El experimento se realizó en la Estação Experimental Agronômica de la Universidade Federal do Rio Grande do Sul, ubicada en Eldorado do Sul, Rio Grande do Sul, Brasil, entre los meses de septiembre de 2003 y abril de 2004, totalizando 225 días de experimentación. El diseño experimental fue de parcelas subdivididas, en factorial 2 x 3, con 4 repeticiones de 22 contenedores cada. En las parcelas principales se evaluaron los sistemas de riego (microaspersión y capilaridad y en las subparcelas los patrones cítricos Poncirus trifoliata (L. Raf., citrangero 'C37' [P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra] y lima 'Rangpur' (C. limonia Osb.. En condiciones de invernadero los patrones cítricos presentan un desarrollo vegetativo más rápido bajo riego por capilaridad respecto a la microaspersión. Los patrones cítricos evaluados presentan desarrollos vegetativos distintos, donde el citrangero 'C37' supera a los demás.The aim of the present work was to evaluate the vegetative development of citrus rootstock seedlings cultivated under greenhouse conditions with two irrigation systems. The experiment was conducted at the Estação Experimental Agronômica , Universidade Federal do Rio Grande do Sul, located in Eldorado do Sul, Rio Grande do Sul, Brazil, from September 2003 to April 2004, totalizing 225 days of experimentation. The experimental design was a split-plot, in a 2x3 factorial, with 4 replications of 22 pots each. In the main plot the irrigation systems was evaluated (micro sprinkler and capillarity and in the split-plot the citrus rootstocks [Trifoliate orange - Poncirus trifoliata (L. Raf., 'C37' citrange - P. trifoliata x Citrus sinensis (L. Osb. cv. Pêra and 'Rangpur' lime - C. limonia Osb.] were evaluated. The main result showed in conditions of greenhouse citrus rootstock seedlings

  8. SOURCES OF MYCORRHIZAL INFECTION OF SHOREA ACUMINATA SEEDLINGS UNDER LABORATORY CONDITIONS

    Directory of Open Access Journals (Sweden)

    LEE Su SEE

    1995-01-01

    Full Text Available Uninoculated dipterocarp seedlings raised in normal field soil in nurseries were always found to have mycorrhizas after a few months. This study set out to determine whether dipterocarp seedlings could continue to grow and develop in the absence of mycorrhizas and also to determine possible sources of mycorrhizal infection of dipterocarp seedlings raised under laboratory conditions using Shorea acuminata as a typical example. Seedlings were planted in capped or uncapped perspex boxes containing sterile or non-sterile field soil and watered daily with sterile water or tap water. Seedling growth and development of mycorrhizas were monitored at monthly intervals for up to seven months. Seedlings grown in sterile soil remained uninfected after seven months while infection was found in some of the seedlings grown in normal soil regardless of whether they had been watered with tap water or sterile water. This showed that field soil (i.e. under grass far from the forest contained suitable inoculum for forest tree seedlings. Tap water and the air were not important sources of infection. However, mycorrhizal infection was very uneven indicating that the inoculum was probably very unevenly distributed in the soil or that the inoculum density was rather low. Seedlings grown in sterile soil showed better growth than those grown in normal soil and infection of roots by parasitic fungi in the latter was also observed.

  9. High-throughput growth prediction for Lactuca sativa L. seedlings using chlorophyll fluorescence in a plant factory with artificial lighting

    Directory of Open Access Journals (Sweden)

    Shogo eMoriyuki

    2016-03-01

    Full Text Available Poorly grown plants that result from differences in individuals lead to large profit losses for plant factories that use large electric power sources for cultivation. Thus, identifying and culling the low-grade seedlings at an early stage, using so-called seedling diagnosis technology, plays an important role in avoiding large losses in plant factories. In this study, we developed a high-throughput diagnosis system using the measurement of chlorophyll fluorescence (CF in a commercial large-scale plant factory, which produces about 5,000 lettuce plants every day. At an early stage (6 days after sowing, a CF image of 6,000 seedlings was captured every 4 hours on the final greening day by a high-sensitivity CCD camera and an automatic transferring machine, and biological indices were extracted. Using machine learning, plant growth can be predicted with a high degree of accuracy based on biological indices including leaf size, amount of CF, and circadian rhythms in CF. Growth prediction was improved by addition of temporal information on CF. The present data also provide new insights into the relationships between growth and temporal information regulated by the inherent biological clock.

  10. Early Holocene lake ecosystem development in the southern Baltic lowlands

    Science.gov (United States)

    Słowiński, Michał; Ott, Florian; Kramkowski, Mateusz; Noryśkiewicz, Agnieszka M.; Zawiska, Izabela; Dräger, Nadine; Theuerkauf, Martin; Hass, Christoph; Obremska, Milena; Błaszkiewicz, Mirosław; Kordowski, Jarosław; Tjallingii, Rik; Rzodkiewicz, Monika; Schwab, Markus; Brauer, Achim

    2016-04-01

    The first millennia of the Holocene are characterized by gradual and rapid environmental changes following the warming at the beginning of the Holocene superimposed by short-term climatic instability. Landscape evolution during this period occurred at different time scales due to specific response times of landscape compartments like vegetation succession, soil formation and permafrost thawing. As a consequence, a spatiotemporally heterogeneous pattern of changes occurred particularly in regions close to the margins of the continental ice sheets like the Baltic region. Regional atmospheric circulation patterns were affected by cold catabatic winds from the remains of the Fennoscandian ice sheet. The ongoing deglaciation further influenced the regional climate through meltwater release and related changes in the North Atlantic thermohaline circulation. Both effects declined with the progressive ice sheet melt down. Additionally, the land-sea distribution in the North Sea changed drastically during the final melting phase of the glacial ice sheets. The Baltic Sea development is even more complex due to the strong glacio-isostatic adjustments effects that resulted in open and closed water stages affecting the entire Baltic realm. Consequently, the early Holocene interval of sediment records from the southern Baltic lowlands are not considered as straightforward palaeoclimate archives but need to be interpreted in a broader context. We present five partly varved lake records from northern Poland all including an intriguing highly organic-rich interval interrupting biochemical calcite precipitation at about the same time between 10.5 and 10.2 cal kyr BP. These sediment records have been correlated by independent age models based on varve counting, AMS 14C dating, biostratigraphy and tephrochronology. We present multi-proxy records of early Holocene sediments and our preliminary interpretation suggests hydrological processes as the main reason for the intriguing shifts

  11. Tomato early blight (Alternaria solani): the pathogen, genetics and breeding for resistance

    OpenAIRE

    Chaerani, R.; Voorrips, R. E.

    2006-01-01

    Alternaria solani causes diseases on foliage (early blight), basal stems of seedlings (collar rot), stems of adult plants (stem lesions), and fruits (fruit rot) of tomato. Early blight is the most destructive of these diseases and hence receives considerable attention in breeding. For over 60 years, breeding for early blight resistance has been practiced, but the development of cultivars with high levels of resistance has been hampered by the lack of sources of strong resistance in the cultiv...

  12. Early physical and motor development of mouse offspring exposed to valproic acid throughout intrauterine development.

    Science.gov (United States)

    Podgorac, Jelena; Pešić, Vesna; Pavković, Željko; Martać, Ljiljana; Kanazir, Selma; Filipović, Ljupka; Sekulić, Slobodan

    2016-09-15

    Clinical research has identified developmental delay and physical malformations in children prenatally exposed to the antiepileptic drug (AED) valproic acid (VPA). However, the early signs of neurodevelopmental deficits, their evolution during postnatal development and growth, and the dose effects of VPA are not well understood. The present study aimed to examine the influence of maternal exposure to a wide dose range (50, 100, 200 and 400mg/kg/day) of VPA during breeding and gestation on early physical and neuromotor development in mice offspring. Body weight gain, eye opening, the surface righting reflex (SRR) and tail suspension test (TST) were examined in the offspring at postnatal days 5, 10 and 15. We observed that: (1) all tested doses of VPA reduced the body weight of the offspring and the timing of eye opening; (2) offspring exposed to VPA displayed immature forms of righting and required more time to complete the SRR; (3) latency for the first immobilization in the TST is shorter in offspring exposed to higher doses of VPA; however, mice in all groups exposed to VPA exhibited atypical changes in this parameter during the examined period of maturation; (4) irregularities in swinging and curling activities were observed in animals exposed to higher doses of VPA. This study points to delayed somatic development and postponed maturation of the motor system in all of the offspring prenatally exposed to VPA, with stronger effects observed at higher doses. The results implicate that the strategy of continuous monitoring of general health and achievements in motor milestones during the early postnatal development in prenatally VPA-exposed offspring, irrespectively of the dose applied, could help to recognize early developmental irregularities.

  13. Rice seedling and plant development as affected by increasing rates of penoxsulam under controlled environments Desenvolvimento de plântulas e plantas adultas de arroz em função de doses crescentes de penoxsulam em ambiente controlado

    Directory of Open Access Journals (Sweden)

    G. Concenço

    2006-01-01

    Full Text Available Rice is a major staple in many countries. Weed control is one of the factors limiting higher rice yield. ALS (acetolactate synthase-inhibiting herbicides are desirable weed control herbicides because of their high efficacy, low toxicity to mammalians, and low rates used. An important herbicide characteristic is high selectivity to the crop, since it facilitates fast crop establishment and greater crop advantage over the weeds. The objectives of this work were to study the effects of increasing rates of the ALS-inhibiting herbicide penoxsulam on seed integrity and germination, and seedling and plant development of rice cv. BRS Pelota under controlled laboratory and greenhouse conditions. The results showed that penoxsulam affected rice germination and seedling and plant growth at rates above 54 g a.i. ha-1, and that penoxsulam is safe for rice seedling development at the currently recommended rates.O arroz é componente importante da dieta humana em vários países. Entre os fatores que limitam o aumento na sua produtividade está o controle de plantas daninhas. Os herbicidas inibidores da ALS (acetolactato sintase são preferidos em razão da alta eficiência no controle de plantas daninhas, da baixa toxicidade aos mamíferos e das baixas doses utilizadas. Uma característica importante que um herbicida deve possuir é a alta seletividade à cultura, pois ela implica estabelecimento mais rápido, com vantagem competitiva sobre as plantas daninhas. O objetivo deste trabalho foi estudar os efeitos do herbicida inibidor da ALS penoxsulam em doses crescentes sobre a integridade e germinação das sementes, bem como sobre o desenvolvimento inicial das plântulas e da planta adulta do cultivar BRS Pelota, sob condições de ambiente controlado (laboratório e casa de vegetação. Os resultados mostraram que o penoxsulam afetou a germinação e o crescimento de plântulas e plantas adultas nas doses acima de 54 g i.a. ha-1 e que ele é seguro para o

  14. Association of Polar Early Career Scientists: a model for experiential learning in professional development for students and early career researchers

    Science.gov (United States)

    Bradley, A. C.; Hindshaw, R. S.; Fugmann, G.; Mariash, H.

    2016-12-01

    The Association of Polar Early Career Scientists was established by early career researchers during the 2007-2008 International Polar Year as an organization for early career researchers in the polar and cryospheric sciences. APECS works to promote early career researchers through soft-skills training in both research and outreach activities, through advocating for including early career researchers in all levels of the scientific process and scientific management, and through supporting a world-wide network of researchers in varied fields. APECS is lead by early career researchers; this self-driven model has proved to be an effective means for developing the leadership, management, and communication skills that are essential in the sciences, and has shown to be sustainable even in a community where frequent turn-over is inherent to the members. Since its inception, APECS has reached over 5,500 members in more than 80 countries, and we have placed more than 50 early career researchers on working groups and steering committees with organizations around the world in the last two years alone. The close partnerships that APECS has with national and international organizations exposes members to both academic and alternative career paths, including those at the science-policy interface. This paper describes APECS's approach to experiential learning in professional development and the best practices identified over our nearly ten years as an organization.

  15. Potential production of Aspidosperma cylindrocarpon seedlings viarescue seedlings

    Directory of Open Access Journals (Sweden)

    Nathália Ferreira e Silva

    Full Text Available ABSTRACT: Translocation of rare populations is regarded as the last resort for the conservation of species whose habitat destruction is imminent. The objective of the present study was to evaluate the effect of two height classes and three leaf reduction intensities on growth and increases in height, stem diameter, survival, and new leaf production in seedlings of Aspidosperma cylindrocarpon (peroba obtained via rescue seedlings in a remnant of tropical semi deciduous forest. We recovered 240 individuals that were divided into two height classes (Class I-5 to 15cm and Class II-20 to 35cm and subjected to three leaf reduction intensities (0%, 50%, and 100%, which were then transported to a shade house with 50% light reduction. Measurements of height, stem diameter, and new leaf production were collected 8 times at 0, 15, 60, 75, 90, 105, 120, and 135 days, and survival rate was measured at day 135. The average survival rate was 82.9%; 77.5% for one Class I (5-15cm and 88.3% for Class II (20-35cm. Higher seedling growth was observed for the 0% leaf reduction treatment in both height classes. The leaves insertion were greater in the 100% cuts, with a decrease observed over time. It is advisable to restore A. cylindrocarpon seedlings in two height classes owing to the high survival rate, leaf appearance, and growth reported in the present study. The no-leaf reduction treatment (0% is the most viable alternative for the production of A. cylindrocarpon seedlings, via rescue seedlings.

  16. A Usage-Based Model of Early Grammatical Development

    NARCIS (Netherlands)

    Beekhuizen, B.; Bod, R.; Fazly, A.; Stevenson, S.; Verhagen, A.; Demberg, V.; O’Donnell, T.

    2014-01-01

    The representations and processes yielding the limited length and telegraphic style of language production early on in acquisition have received little attention in acquisitional modeling. In this paper, we present a model, starting with minimal linguistic representations, that incrementally builds

  17. Investing in early human development: timing and economic efficiency.

    Science.gov (United States)

    Doyle, Orla; Harmon, Colm P; Heckman, James J; Tremblay, Richard E

    2009-03-01

    Policy discussions to ameliorate socioeconomic (SES) inequalities are increasingly focused on investments in early childhood. Yet such interventions are costly to implement, and clear evidence on the optimal time to intervene to yield a high economic and social return in the future is meagre. The majority of successful early childhood interventions start in the preschool years. However socioeconomic gradients in cognitive skills, socio-emotional functioning and health can be observed by age three, suggesting that preventative programmes starting earlier in childhood may be even more effective. We discuss the optimal timing of early childhood intervention with reference to recent research in developmental neuroscience. We motivate the need for early intervention by providing an overview of the impact of adverse risk factors during the antenatal and early childhood periods on outcomes later in life. We provide a brief review of the economic rationale for investing early in life and propose the "antenatal investment hypothesis". We conclude by discussing a suite of new European interventions that will inform this optimal timing debate.

  18. Interactions between ethylene, abscisic acid and cytokinin during germination and seedling establishment in Arabidopsis

    Indian Academy of Sciences (India)

    Veeraputhiran Subbiah; Karingu Janardhan Reddy

    2010-09-01

    In order to investigate the interaction of the plant hormones ethylene, abscisic acid (ABA) and cytokinin in seed germination and early seedling development, we studied germination in ethylene-related mutants of Arabidopsis. Mutations in the genes etr1 and ein2, which reduce ethylene responses, showed increased dormancy and a delay in germination in comparison with wild type. Mutations in etr1, ein2 and ein6 also resulted in increased sensitivity to ABA with respect to inhibition of germination. Conversely, mutations in ctr1 and eto3, which lead to an increased ethylene response and overproduction of ethylene, respectively, decreased sensitivity to ABA during germination. Increased ABA sensitivity was also effected in wild type seeds by the presence during germination of AgNO3, an inhibitor of ethylene action. The addition of the cytokinin N-6 benzyl adenine (BA) reversed the increased sensitivity of ethylene-resistant mutants to ABA. The action of cytokinin in reversing increased ABA sensitivity of ethylene-resistant mutants also suggests that at least part of the action of cytokinin in promoting germination is independent of its role in stimulating ethylene production. These observations further extend the evidence in support of interaction between ethylene, ABA and cytokinin signalling in controlling seed germination and early seedling development in Arabidopsis.

  19. Identification and Seedlings Growth Evaluation of Shorea Species-Producing Tengkawang

    Directory of Open Access Journals (Sweden)

    Eritrina Windyarini

    2015-06-01

    Full Text Available Most of  non timber forest product (NTFP utilization taken from natural forests which decrease on productivity annually, including tengkawang producer species which taken from West Kalimantan natural forests. This condition needs an effort to preserve those species from natural population utilization through plantation forest development that require spesific strategy. This study was part of breeding strategy of shorea species producing tengkawang which aimed to species identify and seedling growth evaluation used genetic material from 2 (two population from West Kalimantan. The research was arranged in 2 (two steps, i.e.1 species identification used morphology characteristic difference, and 2 seedling growth evaluation (height,diameter,sturdiness. Seedling growth evaluation was arranged in RCBD, with 5 plot (combination of species and source population, contained 25 seedlings and 4 replications (blocks. The result showed that seedlings of shorea species producing tengkawang, i.e. S.stenoptera,  S.macrophylla, and S.gysbertsiana can be different from its stipulae morphology characteristic. Growth of 10 months shorea species producing tengkawang seedlings were significantly different on height and sturdiness. Seedlings height were 67,19 – 88,79 cm, seedlings diameter 9,65 – 10,33 mm and sturdiness 7 – 9,21 in range. The best seedling growth was S.stenoptera and S.macrophylla from Gunung Bunga, West Kalimantan.

  20. Identification and Seedlings Growth Evaluation of Shorea Species-Producing Tengkawang

    Directory of Open Access Journals (Sweden)

    Eritrina Windyarini

    2015-06-01

    Full Text Available Most of non timber forest product (NTFP utilization taken from natural forests which decrease on productivity annually, including tengkawang producer species which taken from West Kalimantan natural forests. This condition needs an effort to preserve those species from natural population utilization through plantation forest development that require spesific strategy. This study was part of breeding strategy of shorea species producing tengkawang which aimed to species identify and seedling growth evaluation used genetic material from 2 (two population from West Kalimantan. The research was arranged in 2 (two steps, i.e.1 species identification used morphology characteristic difference, and 2 seedling growth evaluation (height,diameter,sturdiness. Seedling growth evaluation was arranged in RCBD, with 5 plot (combination of species and source population, contained 25 seedlings and 4 replications (blocks. The result showed that seedlings of shorea species producing tengkawang, i.e. S.stenoptera, S.macrophylla, and S.gysbertsiana can be different from its stipulae morphology characteristic. Growth of 10 months shorea species producing tengkawang seedlings were significantly different on height and sturdiness. Seedlings height were 67,19 – 88,79 cm, seedlings diameter 9,65 – 10,33 mm and sturdiness 7 – 9,21 in range. The best seedling growth was S.stenoptera and S.macrophylla from Gunung Bunga, West Kalimantan.

  1. Phenylalanine is required to promote specific developmental responses and prevents cellular damage in response to ultraviolet light in soybean (Glycine max) during the seed-to-seedling transition.

    Science.gov (United States)

    Sullivan, Joe H; Muhammad, DurreShahwar; Warpeha, Katherine M

    2014-01-01

    UV-radiation elicits a suite of developmental (photomorphogenic) and protective responses in plants, but responses early post-germination have received little attention, particularly in intensively bred plants of economic importance. We examined germination, hypocotyl elongation, leaf pubescence and subcellular responses of germinating and/or etiolated soybean (Glycine max (L.) Merr.) seedlings in response to treatment with discrete wavelengths of UV-A or UV-B radiation. We demonstrate differential responses of germinating/young soybean seedlings to a range of UV wavelengths that indicate unique signal transduction mechanisms regulate UV-initiated responses. We have investigated how phenylalanine, a key substrate in the phenylpropanoid pathway, may be involved in these responses. Pubescence may be a key location for phenylalanine-derived protective compounds, as UV-B irradiation increased pubescence and accumulation of UV-absorbing compounds within primary leaf pubescence, visualized by microscopy and absorbance spectra. Mass spectrometry analysis of pubescence indicated that sinapic esters accumulate in the UV-irradiated hairs compared to unirradiated primary leaf tissue. Deleterious effects of some UV-B wavelengths on germination and seedling responses were reduced or entirely prevented by inclusion of phenylalanine in the growth media. Key effects of phenylalanine were not duplicated by tyrosine or tryptophan or sucrose, nor is the specificity of response due to the absorbance of phenylalanine itself. These results suggest that in the seed-to-seedling transition, phenylalanine may be a limiting factor in the development of initial mechanisms of UV protection in the developing leaf.

  2. LIMING AND FERTILIZING FOR MAHOGANI (Switenia macrophylla King. SEEDLING FORMATION

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Franco Tucci

    2007-09-01

    Full Text Available The production of seedlings is one of the most important phases of the cultivation of forest species. Seedlings ofappropriate quality are fundamental in the growth and development of the species. In the production of seedlings, the substratum isfundamental for the good development of the plants. However, the subsoil in general, is acid and it contains low levels of nutritious.The acidity of the soil and the deficiency of nutrients can be corrected through liming and mineral fertilization. The objective of thepresent work was to evaluate the effect of liming and of the fertilization of the soil for the production of mahogany seedlings. Theexperiment was carried out in the period of 120 days, in the Federal University of Amazonas, UFAM. The experimental design wasrandomized complete blocks with statistical analysis in split plot. The plots were composed with eight treatments and four repetitionsand the subplots were eight sampling times of the plants. The treatments were control (natural soil, liming, corrective phosphate,fertilizing with NPK, liming + corrective phosphate, corrective phosphate + fertilizing with NPK, liming + fertilizing with NPK andliming + corrective phosphate + fertilizing with NPK. It was concluded that the associated liming and corrective phosphate and withthe fertilizing with nitrogen, phosphorous and potassium promoted the smallest levels of exchangeable aluminum and the largestlevels of calcium, magnesium, phosphorous and potassium in the soil. These levels of nutrients in the soil caused larger levels ofnutrients in the plants, providing larger growth rate. The liming, corrective phosphate and fertilizing are a fundamental practices inthe formation of mahogany seedlings.

  3. Symbiotic propagation of seedlings of Cyrtopodium glutiniferum Raddi (Orchidaceae

    Directory of Open Access Journals (Sweden)

    Fernanda Aparecida Rodrigues Guimarães

    2013-09-01

    Full Text Available In nature, orchid seeds obtain the nutrients necessary for germination by degrading intracellular fungal structures formed after colonization of the embryo by mycorrhizal fungi. Protocols for asymbiotic germination of orchid seeds typically use media with high concentrations of soluble carbohydrate and minerals. However, when reintroduced into the field, seedlings obtained via asymbiotic germination have lower survival rates than do seedlings obtained via symbiotic germination. Tree fern fiber, the ideal substrate for orchid seedling acclimatization, is increasingly scarce. Here, we evaluated seed germination and protocorm development of Cyrtopodium glutiniferum Raddi cultivated in asymbiotic media (Knudson C and Murashige & Skoog and in oatmeal agar (OA medium inoculated with the mycorrhizal fungus Epulorhiza sp., using non-inoculated OA medium as a control. We also evaluated the performance of tree fern fiber, pine bark, eucalyptus bark, corncob and sawdust as substrates for the acclimatization of symbiotically propagated plants. We determined germination percentages, protocorm development and growth indices at 35 and 70 days of cultivation. Relative growth rates and the effects of substrates on mycorrhizal formation were calculated after 165 days of cultivation. Germination efficiency and growth indices were best when inoculated OA medium was used. Corncob and pine bark showed the highest percentages of colonized system roots. The OA medium inoculated with Epulorhiza sp. shows potential for C. glutiniferum seedling production. Corncob and pine bark are promising substitutes for tree fern fiber as substrates for the acclimatization of orchid seedlings.

  4. Biochemical response of Microwave treatment on Aging beet seed and seedling development%老化甜菜种子微波处理与苗期发育的生化响应

    Institute of Scientific and Technical Information of China (English)

    吴旭红; 段政羽

    2013-01-01

    In present study,seeds of aging beet were exposed to microwave irradiation in different time length and power.Rubisco contents in leaves of beet seeds,proteolytic activity,endogenous H2O2 level,activity of antioxidant enzyme and the corelation were studied.The results showed that carbon and nitrogen metabolism in early stage and material conversion in aging beet seeds were effected by microwave in varying degrees according to treatment time length and sensitivity differences of biochemical indicators.Microwave treatment of 400W 8-13S significantly alleviated Oxidative Stress caused by Seed aging,reduced the level of H2O2,synchronous expression of SOD and APX at high levels and continuous effect of APX have regulated and controlled organically dynamic equilibrium between generation and purge of ROS in aging beet seeds.Microwave treatment of 400W 13-18S resulted in the lowest proteolytic activity which illustrated microwave radiation of this dose reduced the activity of proteolytic enzyme and the sensitivity of this molecular signals through the detoxification to H2O2.Changes in ROS levels passivated proteolytic enzyme system,slowed down the degradation of Rubisco and at the same time Rubisco gene expression was activated which increased the compound of soluble protein Rubisco-played an important role in photosynthesis.In all predefined conditions instantaneous treatment of 400W 13s was the best in promoting aging seed seedling development.%以不同时间和功率的微波对老化甜菜种子进行预处理,对盆栽条件下甜菜幼苗叶片Rubisco含量、蛋白水解酶活性、内源性H2O2水平、抗氧化酶活性及相关性进行了研究.结果表明,微波能不同程度的影响老化甜菜种子萌发后幼苗体内的早期碳氮代谢及物质转化,其影响强度因微波处理时间和生化指标的敏感度不同而异.400W 8-13S微波处理,显著缓解了因种子老化造成的氧化胁迫,降低了H2O2水平,SOD、APX的同步高水平表

  5. Comparisons of hot water microclimate heating and conventional overhead heating on the development and nutritional status of seedling geraniums as well as fuel consumption of these heating regimes

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, M.A.

    1984-01-01

    Two crops of seedling geraniums (Pelargonium x hortorum Bailey) were grown for 16 weeks under the microclimate system using ''Gro-Mat'' ethylene propylene diene monomer (EPDM) tubing and a 10/sup 0/C air -21.1/sup 0/ media temperature environment. Another crop was grown with conventional heating at 16.6/sup 0/ air temperature. Evaluations were made on growth, flowering, nutritional status, and energy consumed. The microclimate system sporadically produced a taller plant during the first eight weeks of the October crop compared to the conventional heated crop; and the December crop was affected only twice during the initial eight weeks. This time the microclimate heating system produced a shorter plant. After week eight there were fewer differences in height. One of the principal differences noted in this study was that the conventionally heated plants flowered seven to ten days earlier than the microclimate plants. By the end of the crop (week 16) few differences in elemental concentrations were detected between the two types of heating systems. The microclimate heating system used about 30% less natural gas than did the conventional system. It appears that microclimate heating systems are a possible alternative to conventional heating systems.

  6. A systems genetics study of seed quality and seedling vigour in Brassica rapa

    NARCIS (Netherlands)

    Basnet, R.K.

    2015-01-01

    Summary Seed is the basic and most critical input for seed propagated agricultural crops: seed quality and seedling vigour determine plant establishment, growth and development in both natural and agricultural ecosystems. Seed quality and seedling vigour are mainly determined by the

  7. Morphotypes of Dactylorhiza incarnata (L. Soу (Orchidaceae seedlings in vitro

    Directory of Open Access Journals (Sweden)

    Oleg A. Marakaev

    2012-03-01

    Full Text Available The morphotypes, linear parameters and morphological features for Dactylorhiza incarnata seedlings in vitro have been set. The uneven growth and development of seedlings in depending from the location and degree of contact with the medium have been identified.

  8. Recovery of l-year-old loblolly pine seedlings from simulated browse damage

    Science.gov (United States)

    Michael G. Shelton; Michael D. Cain

    2002-01-01

    Loblolly pine (Pinus taeda L.) seedlings are frequently browsed by a wide variety of animals during the first few years of their development. Although anecdotal observations indicate that the potential for seedling recovery is good, there is little quantitative information on the factors affecting the recovery process. Thus, we conducted a study to...

  9. The effect of elevated Zn concentrations on seed germination and young seedling growth of Ailanthus altissima (Mill. swingle

    Directory of Open Access Journals (Sweden)

    Samuilov Slađana

    2014-01-01

    Full Text Available Some heavy metals such as Zn are essential micronutrients for plants. However, in a high concentration in soils they could cause repression of growth with toxicity symptoms. It is therefore very important to investigate the species that are tolerant to high concentration of zinc which have the ability to survive on soils contaminated with heavy metals. This paper presents an investigation of the effect of elevated Zn concentrations on the germination and seedling growth of the invasive tree species Ailanthus altissima (Swingle Mill., aimed at a better understanding of its adaptation ability to heavy metal stress and potential use in phytoremediation. Seeds of Ailanthus altissima were treated with Zn concentrations of 25, 100 and 250 μM in form of zinc sulfate. After germination, the seedlings at the stage of first leaf development were transferred into a growing chamber in the hydroponic system where zinc sulfate was added in the concentrations of 100, 250 and 500 μM. The results showed that Zn treatments, including the highest concentration, have caused a reduction in seed germination parameters. Considering the hypocotyl and radicle length, there was no significant statistical difference among the treatments, but further growth of young seedlings in hydroponics under high concentrations of Zn, cause an inhibition of the root system growth and repress development of assimilating organs. Seeds and seedlings of A. altissima are tolerant to elevated Zn concentrations at early stages of development. However, later on with leaves development, the inhibitory effect of the strongest concentrations is expressed. [Projekat Ministarstva nauke Republike Srbije, br. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation

  10. Seed Priming Influence on Early Crop Growth, Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)

    Institute of Scientific and Technical Information of China (English)

    Hafeez ur Rehman; Muhammad Qaiser Nawaz; Shahzad Maqsood Ahmed Basra; Irfan Afzal; Azra Yasmeen; Fayyaz ul-Hassan

    2014-01-01

    Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L-1 salicylic acid (SA), 2.2%CaCl2 and 3.3%moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and lfowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play signiifcant role to improve early crop growth and seed yields of linola.

  11. Linking Play to Early Learning and Development Guidelines: Possibility or Polemic?