WorldWideScience

Sample records for crop plant evolution

  1. Evolution of crop production under a pseudo-space environment using model plants, Lotus japonicus

    Science.gov (United States)

    Tomita-Yokotani, Kaori; Motohashi, Kyohei; Omi, Naomi; Sato, Seigo; Aoki, Toshio; Hashimoto, Hirofumi; Yamashita, Masamichi

    Habitation in outer space is one of our challenges. We have been studying space agriculture and/or spacecraft agriculture to provide food and oxygen for the habitation area in the space environment. However, careful investigation should be made concerning the results of exotic environmental effects on the endogenous production of biologically active substances in indi-vidual cultivated plants in a space environment. We have already reported that the production of functional substances in cultivated plants as crops are affected by gravity. The amounts of the main physiological substances in these plants grown under terrestrial control were different from that grown in a pseudo-microgravity. These results suggested that the nutrition would be changed in the plants/crops grown in the space environment when human beings eat in space. This estimation required us to investigate each of the useful components produced by each plant grown in the space environment. These estimations involved several study fields, includ-ing nutrition, plant physiology, etc. On the other hand, the analysis of model plant genomes has recently been remarkably advanced. Lotus japonicus, a leguminous plant, is also one of the model plant. The leguminosae is a large family in the plant vegetable kingdom and almost the entire genome sequence of Lotus japonicus has been determined. Nitrogen fixation would be possible even in a space environment. We are trying to determine the best conditions and evolution for crop production using the model plants.

  2. Plant domestication versus crop evolution: a conceptual framework for cereals and grain legumes.

    Science.gov (United States)

    Abbo, Shahal; Pinhasi van-Oss, Ruth; Gopher, Avi; Saranga, Yehoshua; Ofner, Itai; Peleg, Zvi

    2014-06-01

    'Domestication syndrome' (DS) denotes differences between domesticated plants and their wild progenitors. Crop plants are dynamic entities; hence, not all parameters distinguishing wild progenitors from cultigens resulted from domestication. In this opinion article, we refine the DS concept using agronomic, genetic, and archaeobotanical considerations by distinguishing crucial domestication traits from traits that probably evolved post-domestication in Near Eastern grain crops. We propose that only traits showing a clear domesticated-wild dimorphism represent the pristine domestication episode, whereas traits showing a phenotypic continuum between wild and domesticated gene pools mostly reflect post-domestication diversification. We propose that our approach may apply to other crop types and examine its implications for discussing the timeframe of plant domestication and for modern plant science and breeding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Plant biotechnology: transgenic crops.

    Science.gov (United States)

    Shewry, Peter R; Jones, Huw D; Halford, Nigel G

    2008-01-01

    Transgenesis is an important adjunct to classical plant breeding, in that it allows the targeted manipulation of specific characters using genes from a range of sources. The current status of crop transformation is reviewed, including methods of gene transfer, the selection of transformed plants and control of transgene expression. The application of genetic modification technology to specific traits is then discussed, including input traits relating to crop production (herbicide tolerance and resistance to insects, pathogens and abiotic stresses) and output traits relating to the composition and quality of the harvested organs. The latter include improving the nutritional quality for consumers as well as the improvement of functional properties for food processing.

  4. Biodiversity, evolution and adaptation of cultivated crops.

    Science.gov (United States)

    Vigouroux, Yves; Barnaud, Adeline; Scarcelli, Nora; Thuillet, Anne-Céline

    2011-05-01

    The human diet depends on very few crops. Current diversity in these crops is the result of a long interaction between farmers and cultivated plants, and their environment. Man largely shaped crop biodiversity from the domestication period 12,000 B.P. to the development of improved varieties during the last century. We illustrate this process through a detailed analysis of the domestication and early diffusion of maize. In smallholder agricultural systems, farmers still have a major impact on crop diversity today. We review several examples of the major impact of man on current diversity. Finally, biodiversity is considered to be an asset for adaptation to current environmental changes. We describe the evolution of pearl millet in West Africa, where average rainfall has decreased over the last forty years. Diversity in cultivated varieties has certainly helped this crop to adapt to climate variation. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  5. Plant senescence and crop productivity

    DEFF Research Database (Denmark)

    Gregersen, Per L.; Culetic, Andrea; Boschian, Luca

    2013-01-01

    Senescence is a developmental process which in annual crop plants overlaps with the reproductive phase. Senescence might reduce crop yield when it is induced prematurely under adverse environmental conditions. This review covers the role of senescence for the productivity of crop plants...... plants, the expression of the IPT gene under control of senescence-associated promoters has been the most successful. The promoters employed for senescence-regulated expression contain cis-elements for binding of WRKY transcription factors and factors controlled by abscisic acid. In most crops...

  6. Plant biotechnology for crop improvement.

    Science.gov (United States)

    Pauls, K P

    1995-01-01

    The typical crop improvement cycle takes 10-15 years to complete and includes germplasm manipulations, genotype selection and stabilization, variety testing, variety increase, proprietary protection and crop production stages. Plant tissue culture and genetic engineering procedures that form the basis of plant biotechnology can contribute to most of these crop improvement stages. This review provides an overview of the opportunities presented by the integration of plant biotechnology into plant improvement efforts and raises some of the societal issues that need to be considered in their application.

  7. Salt resistant crop plants

    KAUST Repository

    Roy, Stuart J.

    2014-04-01

    Soil salinity is a major constraint to agriculture. To improve salinity tolerance of crops, various traits can be incorporated, including ion exclusion, osmotic tolerance and tissue tolerance. We review the roles of a range of genes involved in salt tolerance traits. Different tissues and cells are adapted for specific and often diverse function, so it is important to express the genes in specific cell-types and to pyramid a range of traits. Modern biotechnology (marker- assisted selection or genetic engineering) needs to be increasingly used to introduce the correct combination of genes into elite crop cultivars. Importantly, the effects of introduced genes need to be evaluated in the field to determine their effect on salinity tolerance and yield improvement.

  8. Salt resistant crop plants.

    Science.gov (United States)

    Roy, Stuart J; Negrão, Sónia; Tester, Mark

    2014-04-01

    Soil salinity is a major constraint to agriculture. To improve salinity tolerance of crops, various traits can be incorporated, including ion exclusion, osmotic tolerance and tissue tolerance. We review the roles of a range of genes involved in salt tolerance traits. Different tissues and cells are adapted for specific and often diverse function, so it is important to express the genes in specific cell-types and to pyramid a range of traits. Modern biotechnology (marker-assisted selection or genetic engineering) needs to be increasingly used to introduce the correct combination of genes into elite crop cultivars. Importantly, the effects of introduced genes need to be evaluated in the field to determine their effect on salinity tolerance and yield improvement. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Crop plants as models for understanding plant adaptation and diversification

    Directory of Open Access Journals (Sweden)

    Kenneth M Olsen

    2013-08-01

    Full Text Available Since the time of Darwin, biologists have understood the promise of crop plants and their wild relatives for providing insight into the mechanisms of phenotypic evolution. The intense selection imposed by our ancestors during plant domestication and subsequent crop improvement has generated remarkable transformations of plant phenotypes. Unlike evolution in natural settings, descendent and antecedent conditions for crop plants are often both extant, providing opportunities for direct comparisons through crossing and other experimental approaches. Moreover, since domestication has repeatedly generated a suite of domestication syndrome traits that are shared among crops, opportunities exist for gaining insight into the genetic and developmental mechanisms that underlie parallel adaptive evolution. Advances in our understanding of the genetic architecture of domestication-related traits have emerged from combining powerful molecular technologies with advanced experimental designs, including nested association mapping, genome-wide association studies, population genetic screens for signatures of selection, and candidate gene approaches. These studies may be combined with high-throughput evaluations of the various omics involved in trait transformation, revealing a diversity of underlying causative mutations affecting phenotypes and their downstream propagation through biological networks. We summarize the state of our knowledge of the mutational spectrum that generates phenotypic novelty in domesticated plant species, and our current understanding of how domestication can reshape gene expression networks and emergent phenotypes. An exploration of traits that have been subject to similar selective pressures across crops (e.g., flowering time suggests that a diversity of targeted genes and causative mutational changes can underlie parallel adaptation in the context of crop evolution.

  10. SALT TOLERANCE OF CROP PLANTS

    Directory of Open Access Journals (Sweden)

    Hamdia, M. A

    2010-09-01

    Full Text Available Several environmental factors adversely affect plant growth and development and final yield performance of a crop. Drought, salinity, nutrient imbalances (including mineral toxicities and deficiencies and extremes of temperature are among the major environmental constraints to crop productivity worldwide. Development of crop plants with stress tolerance, however, requires, among others, knowledge of the physiological mechanisms and genetic controls of the contributing traits at different plant developmental stages. In the past 2 decades, biotechnology research has provided considerable insights into the mechanism of biotic stress tolerance in plants at the molecular level. Furthermore, different abiotic stress factors may provoke osmotic stress, oxidative stress and protein denaturation in plants, which lead to similar cellular adaptive responses such as accumulation of compatible solutes, induction of stress proteins, and acceleration of reactive oxygen species scavenging systems. Recently, the authores try to improve plant tolerance to salinity injury through either chemical treatments (plant hormones, minerals, amino acids, quaternary ammonium compounds, polyamines and vitamins or biofertilizers treatments (Asymbiotic nitrogen-fixing bacteria, symbiotic nitrogen-fixing bacteria and mycorrhiza or enhanced a process used naturally by plants to minimise the movement of Na+ to the shoot, using genetic modification to amplify the process, helping plants to do what they already do - but to do it much better."

  11. Biodiversity, evolution and adaptation of cultivated crops

    OpenAIRE

    Vigouroux, Yves; Barnaud, Adeline; Scarcelli, Nora; Thuillet, Anne-Céline

    2011-01-01

    The human diet depends on very few crops. Current diversity in these crops is the result of a long interaction between farmers and cultivated plants, and their environment. Man largely shaped crop biodiversity from the domestication period 12,000 B.P. to the development of improved varieties during the last century. We illustrate this process through a detailed analysis of the domestication and early diffusion of maize. In smallholder agricultural systems, farmers still have a major impact on...

  12. Enhancing (crop) plant photosynthesis by introducing novel genetic diversity.

    Science.gov (United States)

    Dann, Marcel; Leister, Dario

    2017-09-26

    Although some elements of the photosynthetic light reactions might appear to be ideal, the overall efficiency of light conversion to biomass has not been optimized during evolution. Because crop plants are depleted of genetic diversity for photosynthesis, efforts to enhance its efficiency with respect to light conversion to yield must generate new variation. In principle, three sources of natural variation are available: (i) rare diversity within extant higher plant species, (ii) photosynthetic variants from algae, and (iii) reconstruction of no longer extant types of plant photosynthesis. Here, we argue for a novel approach that outsources crop photosynthesis to a cyanobacterium that is amenable to adaptive evolution. This system offers numerous advantages, including a short generation time, virtually unlimited population sizes and high mutation rates, together with a versatile toolbox for genetic manipulation. On such a synthetic bacterial platform, 10 000 years of (crop) plant evolution can be recapitulated within weeks. Limitations of this system arise from its unicellular nature, which cannot reproduce all aspects of crop photosynthesis. But successful establishment of such a bacterial host for crop photosynthesis promises not only to enhance the performance of eukaryotic photosynthesis but will also reveal novel facets of the molecular basis of photosynthetic flexibility.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Author(s).

  13. Epigenetics and Plant Evolution

    National Research Council Canada - National Science Library

    Ryan A. Rapp; Jonathan F. Wendel

    2005-01-01

    .... Here, we provide an introduction to epigenetic mechanisms in plants, and highlight some of the empirical studies illustrative of the possible connections between evolution and epigenetically mediated alterations in gene expression and morphology.

  14. Evolution, plant breeding and biodiversity

    Directory of Open Access Journals (Sweden)

    Salvatore Ceccarelli

    2011-11-01

    Full Text Available This paper deals with changes in biodiversity during the course of evolution, plant domestication and plant breeding. It shows than man has had a strong influence on the progressive decrease of biodiversity, unconscious at first and deliberate in modern times. The decrease in biodiversity in the agricultures of the North causes a severe threat to food security and is in contrasts with the conservation of biodiversity which is part of the culture of several populations in the South. The concluding section of the paper shows that man could have guided evolution in a different way and shows an example of participatory plant breeding, a type of breeding which is done in collaboration with farmers and is based on selection for specific adaptation. Even though participatory plant breeding has been practiced for only about 20 years and by relatively few groups, the effects on both biodiversity and crop production are impressive. Eventually the paper shows how participatory plant breeding can be developed into ‘evolutionary plant breeding’ to cope in a dynamic way with climate changes.

  15. Plant exomics: concepts, applications and methodologies in crop improvement.

    Science.gov (United States)

    Hashmi, Uzair; Shafqat, Samia; Khan, Faria; Majid, Misbah; Hussain, Harris; Kazi, Alvina Gul; John, Riffat; Ahmad, Parvaiz

    2015-01-01

    Molecular breeding has a crucial role in improvement of crops. Conventional breeding techniques have failed to ameliorate food production. Next generation sequencing has established new concepts of molecular breeding. Exome sequencing has proven to be a significant tool for assessing natural evolution in plants, studying host pathogen interactions and betterment of crop production as exons assist in interpretation of allelic variation with respect to their phenotype. This review covers the platforms for exome sequencing, next generation sequencing technologies that have revolutionized exome sequencing and led toward development of third generation sequencing. Also discussed in this review are the uses of these sequencing technologies to improve wheat, rice and cotton yield and how these technologies are used in exploring the biodiversity of crops, providing better understanding of plant-host pathogen interaction and assessing the process of natural evolution in crops and it also covers how exome sequencing identifies the gene pool involved in symbiotic and other co-existential systems. Furthermore, we conclude how integration of other methodologies including whole genome sequencing, proteomics, transcriptomics and metabolomics with plant exomics covers the areas which are left untouched with exomics alone and in the end how these integration will transform the future of crops.

  16. Multi-Crop Specific Area Frame Stratification Based on Geospatial Crop Planting Frequency Data Layers

    Science.gov (United States)

    Boryan, C. G.; Yang, Z.; Willis, P.; Di, L.

    2016-12-01

    Area sampling frames (ASFs) are the basis of many statistical programs around the world. When an ASF's stratification is based on generalized percent cultivation, the ASF usually cannot identify the planting location of specific crops targeted for agricultural surveys. To improve the accuracy, objectivity and efficiency of crop survey estimates, an automated stratification method based on geospatial crop planting frequency data is proposed. The Crop Planting Frequency Data Layers are crop specific geospatial data sets derived from multi-year Cropland Data Layers. Therefore, the ASF stratification based on the crop planting frequency data is crop specific. This paper investigates using 2008-2013 geospatial Crop Frequency Data Layers to create a novel multi-crop specific stratification for South Dakota, U.S. The crop specific ASF stratification is developed based on crop frequency statistics calculated at the primary sampling unit (PSU) level based on the corn, soybean and wheat planting frequency data layers, three major crops in South Dakota. Strata are formed using a k means clustering algorithm. It is observed that the crop frequency based ASF stratification predicts corn, soybean and wheat planting patterns well as verified by 2014 Farm Service Agency (FSA) Common Land Unit (CLU) and 578 administrative data. This finding demonstrates that the novel multi-crop specific stratification based on crop planting frequency data is crop type independent and applicable to all major crops. Further, these results indicate that the new multi-crop specific ASF stratification has great potential to improve ASF accuracy, efficiency and crop estimates.

  17. Metabolic engineering of micronutrients in crop plants.

    Science.gov (United States)

    Blancquaert, Dieter; De Steur, Hans; Gellynck, Xavier; Van Der Straeten, Dominique

    2017-02-01

    Micronutrient deficiency is a widespread phenomenon, most prevalent in developing countries. Being causally linked to the occurrence of a range of diseases, it affects billions of people worldwide. Enhancing the content of micronutrients in crop products through biotechnology is a promising technique to fight micronutrient malnutrition worldwide. Micronutrient fortification of food products has been implemented in a number of Western countries, but remains inaccessible for poor rural populations in a major part of the developing world. Moreover, evidence of the negative impacts of this practice on human health, at least for some vitamins, is accumulating. Biofortification of crop plants-the enhancement of vitamins and minerals through plant biotechnology-is a promising alternative or complement in the battle against micronutrient deficiencies. Owing to a growing knowledge about vitamin metabolism, as well as mineral uptake and reallocation in plants, it is today possible to enhance micronutrient levels in crop plants, offering a sustainable solution to populations with a suboptimal micronutrient intake. © 2016 New York Academy of Sciences.

  18. Engineering Cold Stress Tolerance in Crop Plants

    Science.gov (United States)

    Sanghera, Gulzar S; Wani, Shabir H; Hussain, Wasim; Singh, N.B

    2011-01-01

    Plants respond with changes in their pattern of gene expression and protein products when exposed to low temperatures. Thus ability to adapt has an impact on the distribution and survival of the plant, and on crop yields. Many species of tropical or subtropical origin are injured or killed by non-freezing low temperatures, and exhibit various symptoms of chilling injury such as chlorosis, necrosis, or growth retardation. In contrast, chilling tolerant species are able to grow at such cold temperatures. Conventional breeding methods have met with limited success in improving the cold tolerance of important crop plants involving inter-specific or inter-generic hybridization. Recent studies involving full genome profiling/ sequencing, mutational and transgenic plant analyses, have provided a deep insight of the complex transcriptional mechanism that operates under cold stress. The alterations in expression of genes in response to cold temperatures are followed by increases in the levels of hundreds of metabolites, some of which are known to have protective effects against the damaging effects of cold stress. Various low temperature inducible genes have been isolated from plants. Most appear to be involved in tolerance to cold stress and the expression of some of them is regulated by C-repeat binding factor/ dehydration-responsive element binding (CBF/DREB1) transcription factors. Numerous physiological and molecular changes occur during cold acclimation which reveals that the cold resistance is more complex than perceived and involves more than one pathway. The findings summarized in this review have shown potential practical applications for breeding cold tolerance in crop and horticultural plants suitable to temperate geographical locations. PMID:21886453

  19. Engineering cold stress tolerance in crop plants.

    Science.gov (United States)

    Sanghera, Gulzar S; Wani, Shabir H; Hussain, Wasim; Singh, N B

    2011-03-01

    Plants respond with changes in their pattern of gene expression and protein products when exposed to low temperatures. Thus ability to adapt has an impact on the distribution and survival of the plant, and on crop yields. Many species of tropical or subtropical origin are injured or killed by non-freezing low temperatures, and exhibit various symptoms of chilling injury such as chlorosis, necrosis, or growth retardation. In contrast, chilling tolerant species are able to grow at such cold temperatures. Conventional breeding methods have met with limited success in improving the cold tolerance of important crop plants involving inter-specific or inter-generic hybridization. Recent studies involving full genome profiling/ sequencing, mutational and transgenic plant analyses, have provided a deep insight of the complex transcriptional mechanism that operates under cold stress. The alterations in expression of genes in response to cold temperatures are followed by increases in the levels of hundreds of metabolites, some of which are known to have protective effects against the damaging effects of cold stress. Various low temperature inducible genes have been isolated from plants. Most appear to be involved in tolerance to cold stress and the expression of some of them is regulated by C-repeat binding factor/ dehydration-responsive element binding (CBF/DREB1) transcription factors. Numerous physiological and molecular changes occur during cold acclimation which reveals that the cold resistance is more complex than perceived and involves more than one pathway. The findings summarized in this review have shown potential practical applications for breeding cold tolerance in crop and horticultural plants suitable to temperate geographical locations.

  20. Production of renewable polymers from crop plants.

    Science.gov (United States)

    van Beilen, Jan B; Poirier, Yves

    2008-05-01

    Plants produce a range of biopolymers for purposes such as maintenance of structural integrity, carbon storage, and defense against pathogens and desiccation. Several of these natural polymers are used by humans as food and materials, and increasingly as an energy carrier. In this review, we focus on plant biopolymers that are used as materials in bulk applications, such as plastics and elastomers, in the context of depleting resources and climate change, and consider technical and scientific bottlenecks in the production of novel or improved materials in transgenic or alternative crop plants. The biopolymers discussed are natural rubber and several polymers that are not naturally produced in plants, such as polyhydroxyalkanoates, fibrous proteins and poly-amino acids. In addition, monomers or precursors for the chemical synthesis of biopolymers, such as 4-hydroxybenzoate, itaconic acid, fructose and sorbitol, are discussed briefly.

  1. Effects of unsaturated hydrocarbons on crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Hall, W.C.; Heck, W.W.

    1960-01-01

    Damage to cotton and other crops in the vicinity of a Gulf Coast polyethylene plant has led to studies on the causative agent or agents responsible for crop losses. Responses exhibited by both native and cultivated plants of the area led to an initial diagnosis that the symptoms were caused by ethylene present in relatively high amounts in the atmosphere. Analysis of the stack gas showed 1.5% ethylene, 0.3% ethane, 8.7% carbon dioxide, 0.3% ethylene oxide and minute amounts of methane. Field analyses have shown concentrations of ethylene aging from 0.04 to 3 ppm depending upon atmospheric conditions (wind direction and velocity) as well as distance from the polyethylene plant. Various mixtures of hydrocarbon gases have been tested using cotton, coleus, tomato and other plant species. Ethylene has been found to be the most biologically active of the hydrocarbon gases studied. Controlled experiments have confirmed field observations that monocotyledonous plants such as sorghum and corn are relatively insensitive to ethylene, whereas dicotyledonous plants such as cotton, coleus, corn pea and tomato are extremely sensitive. Flower petal abscission in periwinkle and flower bud abscission in cotton have been found to be excellent indicators of extremely low levels of ethylene air pollution in both the field and in controlled experiments. Typical responses of cotton to low levels of ethylene include: lost of apical dominance with the resulting prostrate growth habit, flattening of upper stem and growing point, forcing of lateral buds, weakening of main stem, compacting of internodes, earlier and more profuse flowering with the abscission of squares, total loss of yield. 2 references.

  2. Selecting and Using Plant Growth Regulators on Floricultural Crops

    OpenAIRE

    Latimer, Joyce G.; Whipker, Brian

    2013-01-01

    Explains the factors to consider when selecting and using plant growth regulators, chemicals designed to affect plant growth and/or development, in order to achieve best results on floricultural crops and includes an appendix listing plant growth regulators by crop type.

  3. Modification of flavonoid biosynthesis in crop plants.

    Science.gov (United States)

    Schijlen, Elio G W M; Ric de Vos, C H; van Tunen, Arjen J; Bovy, Arnaud G

    2004-10-01

    Flavonoids comprise the most common group of polyphenolic plant secondary metabolites. In plants, flavonoids play an important role in biological processes. Beside their function as pigments in flowers and fruits, to attract pollinators and seed dispersers, flavonoids are involved in UV-scavenging, fertility and disease resistance. Since they are present in a wide range of fruits and vegetables, flavonoids form an integral part of the human diet. Currently there is broad interest in the effects of dietary polyphenols on human health. In addition to the potent antioxidant activity of many of these compounds in vitro, an inverse correlation between the intake of certain polyphenols and the risk of cardiovascular disease, cancer and other age related diseases has been observed in epidemiological studies. The potential nutritional effects of these molecules make them an attractive target for genetic engineering strategies aimed at producing plants with increased nutritional value. This review describes the current knowledge of the molecular regulation of the flavonoid pathway and the state of the art with respect to metabolic engineering of this pathway in crop plants.

  4. Relationships between phenological and yield traits of the plant crop ...

    African Journals Online (AJOL)

    Multiple correlation of phenological and yield traits of the plant crop (PC) with those of the first ratoon crop (RC) of 36 Musa genotypes was carried out. The genotypes were landraces (triploid) belonging to AAA, AAB and ABB Musa genomic groups and hybrids (mostly tetraploid) thereof. The plants were grown under four ...

  5. Genomics Approaches For Improving Salinity Stress Tolerance in Crop Plants

    Science.gov (United States)

    Nongpiur, Ramsong Chantre; Singla-Pareek, Sneh Lata; Pareek, Ashwani

    2016-01-01

    Salinity is one of the major factors which reduces crop production worldwide. Plant responses to salinity are highly complex and involve a plethora of genes. Due to its multigenicity, it has been difficult to attain a complete understanding of how plants respond to salinity. Genomics has progressed tremendously over the past decade and has played a crucial role towards providing necessary knowledge for crop improvement. Through genomics, we have been able to identify and characterize the genes involved in salinity stress response, map out signaling pathways and ultimately utilize this information for improving the salinity tolerance of existing crops. The use of new tools, such as gene pyramiding, in genetic engineering and marker assisted breeding has tremendously enhanced our ability to generate stress tolerant crops. Genome editing technologies such as Zinc finger nucleases, TALENs and CRISPR/Cas9 also provide newer and faster avenues for plant biologists to generate precisely engineered crops. PMID:27499683

  6. An Investigation of Generalized Differential Evolution Metaheuristic for Multiobjective Optimal Crop-Mix Planning Decision

    Science.gov (United States)

    Olugbara, Oludayo

    2014-01-01

    This paper presents an annual multiobjective crop-mix planning as a problem of concurrent maximization of net profit and maximization of crop production to determine an optimal cropping pattern. The optimal crop production in a particular planting season is a crucial decision making task from the perspectives of economic management and sustainable agriculture. A multiobjective optimal crop-mix problem is formulated and solved using the generalized differential evolution 3 (GDE3) metaheuristic to generate a globally optimal solution. The performance of the GDE3 metaheuristic is investigated by comparing its results with the results obtained using epsilon constrained and nondominated sorting genetic algorithms—being two representatives of state-of-the-art in evolutionary optimization. The performance metrics of additive epsilon, generational distance, inverted generational distance, and spacing are considered to establish the comparability. In addition, a graphical comparison with respect to the true Pareto front for the multiobjective optimal crop-mix planning problem is presented. Empirical results generally show GDE3 to be a viable alternative tool for solving a multiobjective optimal crop-mix planning problem. PMID:24883369

  7. An investigation of generalized differential evolution metaheuristic for multiobjective optimal crop-mix planning decision.

    Science.gov (United States)

    Adekanmbi, Oluwole; Olugbara, Oludayo; Adeyemo, Josiah

    2014-01-01

    This paper presents an annual multiobjective crop-mix planning as a problem of concurrent maximization of net profit and maximization of crop production to determine an optimal cropping pattern. The optimal crop production in a particular planting season is a crucial decision making task from the perspectives of economic management and sustainable agriculture. A multiobjective optimal crop-mix problem is formulated and solved using the generalized differential evolution 3 (GDE3) metaheuristic to generate a globally optimal solution. The performance of the GDE3 metaheuristic is investigated by comparing its results with the results obtained using epsilon constrained and nondominated sorting genetic algorithms-being two representatives of state-of-the-art in evolutionary optimization. The performance metrics of additive epsilon, generational distance, inverted generational distance, and spacing are considered to establish the comparability. In addition, a graphical comparison with respect to the true Pareto front for the multiobjective optimal crop-mix planning problem is presented. Empirical results generally show GDE3 to be a viable alternative tool for solving a multiobjective optimal crop-mix planning problem.

  8. Association of non-heterocystous cyanobacteria with crop plants

    NARCIS (Netherlands)

    Ahmed, M.; Stal, L.J.; Hasnain, S.

    2010-01-01

    Cyanobacteria have the ability to form associations with organisms from all domains of life, notably with plants, which they provide with fixed nitrogen, among other substances. This study was aimed at developing artificial associations between nonheterocystous cyanobacteria and selected crop

  9. Large SNP arrays for genotyping in crop plants

    Indian Academy of Sciences (India)

    2012-10-15

    sequencing has the advantage that essen- tially all SNPs in single-copy sequences between individuals can be identified. This has been demonstrated for crop plants such as maize, rice and soybean (Huang et al. 2009; Lai.

  10. Glyphosate Effects on Plant Mineral Nutrition, Crop Rhizosphere Microbiota, and Plant Disease in Glyphosate-Resistant Crops

    Science.gov (United States)

    2012-01-01

    Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the literature indicates that mineral nutrition in GR crops is not affected by either the GR trait or by application of glyphosate; (2) most of the available data support the view that neither the GR transgenes nor glyphosate use in GR crops increases crop disease; and (3) yield data on GR crops do not support the hypotheses that there are substantive mineral nutrition or disease problems that are specific to GR crops. PMID:23013354

  11. Energy crops for biogas plants. Thuringia; Energiepflanzen fuer Biogasanlagen. Thueringen

    Energy Technology Data Exchange (ETDEWEB)

    Biertuempfel, A.; Bischof, R.; Conrad, M. (and others)

    2012-06-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Thuringia. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  12. Energy crops for biogas plants. Saxony; Energiepflanzen fuer Biogasanlagen. Sachsen

    Energy Technology Data Exchange (ETDEWEB)

    Biertuempfel, A.; Buttlar, C. von; Conrad, M. [and others

    2012-08-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Saxony. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  13. Oilseed rape: learning about ancient and recent polyploid evolution from a recent crop species.

    Science.gov (United States)

    Mason, A S; Snowdon, R J

    2016-11-01

    Oilseed rape (Brassica napus) is one of our youngest crop species, arising several times under cultivation in the last few thousand years and completely unknown in the wild. Oilseed rape originated from hybridisation events between progenitor diploid species B. rapa and B. oleracea, both important vegetable species. The diploid progenitors are also ancient polyploids, with remnants of two previous polyploidisation events evident in the triplicated genome structure. This history of polyploid evolution and human agricultural selection makes B. napus an excellent model with which to investigate processes of genomic evolution and selection in polyploid crops. The ease of de novo interspecific hybridisation, responsiveness to tissue culture, and the close relationship of oilseed rape to the model plant Arabidopsis thaliana, coupled with the recent availability of reference genome sequences and suites of molecular cytogenetic and high-throughput genotyping tools, allow detailed dissection of genetic, genomic and phenotypic interactions in this crop. In this review we discuss the past and present uses of B. napus as a model for polyploid speciation and evolution in crop species, along with current and developing analysis tools and resources. We further outline unanswered questions that may now be tractable to investigation. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  14. Evolution of the Crop Rhizosphere: Impact of Domestication on Root Exudates in Tetraploid Wheat (Triticum turgidum L.)

    OpenAIRE

    Iannucci, Anna; Fragasso, Mariagiovanna; Beleggia, Romina; Nigro, Franca; Papa, Roberto

    2017-01-01

    Domestication has induced major genetic changes in crop plants to satisfy human needs and as a consequence of adaptation to agroecosystems. This adaptation might have affected root exudate composition, which can influence the interactions in the rhizosphere. Here, using two different soil types (sand, soil), we provide an original example of the impact of domestication and crop evolution on root exudate composition through metabolite profiling of root exudates for a panel of 10 wheat genotype...

  15. Do Refuge Plants Favour Natural Pest Control in Maize Crops?

    Science.gov (United States)

    Quispe, Reinaldo; Mazón, Marina; Rodríguez-Berrío, Alexander

    2017-01-01

    The use of non-crop plants to provide the resources that herbivorous crop pests’ natural enemies need is being increasingly incorporated into integrated pest management programs. We evaluated insect functional groups found on three refuges consisting of five different plant species each, planted next to a maize crop in Lima, Peru, to investigate which refuge favoured natural control of herbivores considered as pests of maize in Peru, and which refuge plant traits were more attractive to those desirable enemies. Insects occurring in all the plants, including the maize crop itself, were sampled weekly during the crop growing cycle, from February to June 2011. All individuals collected were identified and classified into three functional groups: herbivores, parasitoids, and predators. Refuges were compared based on their effectiveness in enhancing the populations of predator and parasitoid insects of the crop enemies. Refuges A and B were the most effective, showing the highest richness and abundance of both predators and parasitoids, including several insect species that are reported to attack the main insect pests of maize (Spodoptera frugiperda and Rhopalosiphum maidis), as well as other species that serve as alternative hosts of these natural enemies. PMID:28718835

  16. Modification of flavonoid biosynthesis in crop plants

    NARCIS (Netherlands)

    Schijlen, E.G.W.M.; Vos, de C.H.; Tunen, van A.J.; Bovy, A.G.

    2004-01-01

    Flavonoids comprise the most common group of polyphenolic plant secondary metabolites. In plants, flavonoids play an important role in biological processes. Beside their function as pigments in flowers and fruits, to attract pollinators and seed dispersers, flavonoids are involved in UV-scavenging,

  17. Plant factories; crop transpiration and energy balance

    NARCIS (Netherlands)

    Graamans, Luuk; Dobbelsteen, van den Andy; Meinen, Esther; Stanghellini, Cecilia

    2017-01-01

    Population growth and rapid urbanisation may result in a shortage of food supplies for cities in the foreseeable future. Research on closed plant production systems, such as plant factories, has attempted to offer perspectives for robust (urban) agricultural systems. Insight into the explicit role

  18. Boosting beneficial phytochemicals in vegetable crop plants

    NARCIS (Netherlands)

    Schijlen, E.G.W.M.; Beekwilder, M.J.; Hall, R.D.; Meer, van der I.M.

    2008-01-01

    Plants contain an astonishing diversity of biochemical pathways, which eventually result in the production and accumulation of innumerable phytochemical compounds. From an historical point of view, people have primarily selected plants on the basis of traits that are linked to the presence of

  19. Agronomic conditions and crop evolution in ancient Near East agriculture.

    Science.gov (United States)

    Araus, José L; Ferrio, Juan P; Voltas, Jordi; Aguilera, Mònica; Buxó, Ramón

    2014-05-23

    The appearance of agriculture in the Fertile Crescent propelled the development of Western civilization. Here we investigate the evolution of agronomic conditions in this region by reconstructing cereal kernel weight and using stable carbon and nitrogen isotope signatures of kernels and charcoal from a set of 11 Upper Mesopotamia archaeological sites, with chronologies spanning from the onset of agriculture to the turn of the era. We show that water availability for crops, inferred from carbon isotope discrimination (Δ(13)C), was two- to fourfold higher in the past than at present, with a maximum between 10,000 and 8,000 cal BP. Nitrogen isotope composition (δ(15)N) decreased over time, which suggests cultivation occurring under gradually less-fertile soil conditions. Domesticated cereals showed a progressive increase in kernel weight over several millennia following domestication. Our results provide a first comprehensive view of agricultural evolution in the Near East inferred directly from archaeobotanical remains.

  20. Targeted modification of plant genomes for precision crop breeding.

    Science.gov (United States)

    Hilscher, Julia; Bürstmayr, Hermann; Stoger, Eva

    2017-01-01

    The development of gene targeting and gene editing techniques based on programmable site-directed nucleases (SDNs) has increased the precision of genome modification and made the outcomes more predictable and controllable. These approaches have achieved rapid advances in plant biotechnology, particularly the development of improved crop varieties. Here, we review the range of alterations which have already been implemented in plant genomes, and summarize the reported efficiencies of precise genome modification. Many crop varieties are being developed using SDN technologies and although their regulatory status in the USA is clear there is still a decision pending in the EU. DNA-free genome editing strategies are briefly discussed because they also present a unique regulatory challenge. The potential applications of genome editing in plant breeding and crop improvement are highlighted by drawing examples from the recent literature. Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Spatio-Temporal Variation in Landscape Composition May Speed Resistance Evolution of Pests to Bt Crops.

    Science.gov (United States)

    Ives, Anthony R; Paull, Cate; Hulthen, Andrew; Downes, Sharon; Andow, David A; Haygood, Ralph; Zalucki, Myron P; Schellhorn, Nancy A

    2017-01-01

    Transgenic crops that express insecticide genes from Bacillus thuringiensis (Bt) are used worldwide against moth and beetle pests. Because these engineered plants can kill over 95% of susceptible larvae, they can rapidly select for resistance. Here, we use a model for a pyramid two-toxin Bt crop to explore the consequences of spatio-temporal variation in the area of Bt crop and non-Bt refuge habitat. We show that variability over time in the proportion of suitable non-Bt breeding habitat, Q, or in the total area of Bt and suitable non-Bt habitat, K, can increase the overall rate of resistance evolution by causing short-term surges of intense selection. These surges can be exacerbated when temporal variation in Q and/or K cause high larval densities in refuges that increase density-dependent mortality; this will give resistant larvae in Bt fields a relative advantage over susceptible larvae that largely depend on refuges. We address the effects of spatio-temporal variation in a management setting for two bollworm pests of cotton, Helicoverpa armigera and H. punctigera, and field data on landscape crop distributions from Australia. Even a small proportion of Bt fields available to egg-laying females when refuges are sparse may result in high exposure to Bt for just a single generation per year and cause a surge in selection. Therefore, rapid resistance evolution can occur when Bt crops are rare rather than common in the landscape. These results highlight the need to understand spatio-temporal fluctuations in the landscape composition of Bt crops and non-Bt habitats in order to design effective resistance management strategies.

  2. ROS regulation during abiotic stress responses in crop plants

    Directory of Open Access Journals (Sweden)

    Jun eYou

    2015-12-01

    Full Text Available Abiotic stresses such as drought, cold, salt and heat cause reduction of plant growth and loss of crop yield worldwide. Reactive oxygen species (ROS including hydrogen peroxide (H2O2, superoxide anions (O2•‾, hydroxyl radical (OH• and singlet oxygen (1O2 are by-products of physiological metabolisms, and are precisely controlled by enzymatic and non-enzymatic antioxidant defense systems. ROS are significantly accumulated under abiotic stress conditions, which cause oxidative damage and eventually resulting in cell death. Recently, ROS have been also recognized as key players in the complex signaling network of plants stress responses. The involvement of ROS in signal transduction implies that there must be coordinated function of regulation networks to maintain ROS at non-toxic levels in a delicate balancing act between ROS production, involving ROS generating enzymes and the unavoidable production of ROS during basic cellular metabolism, and ROS-scavenging pathways. Increasing evidence showed that ROS play crucial roles in abiotic stress responses of crop plants for the activation of stress-response and defense pathways. More importantly, manipulating ROS levels provides an opportunity to enhance stress tolerances of crop plants under a variety of unfavorable environmental conditions. This review presents an overview of current knowledge about homeostasis regulation of ROS in crop plants. In particular, we summarize the essential proteins that are involved in abiotic stress tolerance of crop plants through ROS regulation. Finally, the challenges toward the improvement of abiotic stress tolerance through ROS regulation in crops are discussed.

  3. Production of renewable polymers from crop plants

    National Research Council Canada - National Science Library

    Van Beilen, Jan B; Poirier, Yves

    2008-01-01

    .... In this review, we focus on plant biopolymers that are used as materials in bulk applications, such as plastics and elastomers, in the context of depleting resources and climate change, and consider...

  4. Non-GMO genetically edited crop plants.

    Science.gov (United States)

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Velasco, Riccardo; Kim, Jin-Soo; Viola, Roberto

    2015-09-01

    Direct delivery of purified Cas9 protein with guide RNA into plant cells, as opposed to plasmid-mediated delivery, displays high efficiency and reduced off-target effects. Following regeneration from edited cells, the ensuing plant is also likely to bypass genetically modified organism (GMO) legislation as the genome editing complex is degraded in the recipient cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Plant Evolution: A Manufacturing Network Perspective

    DEFF Research Database (Denmark)

    Yang, Cheng; Johansen, John; Boer, Harry

    2009-01-01

    Viewing them as portfolios of products and processes, we aim to address how plants evolve in the context of a manufacturing network and how the evolution of one plant impacts other plants in the same manufacturing network. Based on discussions of ten plants from three Danish companies, we identif...

  6. Uranium uptake by hydroponically cultivated crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dvorakova, Marcela [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.cz [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic)

    2011-06-15

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC{sub 50} value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC{sub 50} = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: > The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. > Uranium is mainly localized in the root system. > Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. > The phosphates deficiency increase the uranium uptake.

  7. The evolution of plant virus transmission pathways

    Science.gov (United States)

    Frédéric M. Hamelin; Linda J.S. Allen; Holly R. Prendeville; M. Reza Hajimorad; Michael J. Jeger

    2016-01-01

    The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, oravector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which...

  8. Impact of interspecific hybridization between crops and weedy relatives on the evolution of flowering time in weedy phenotypes.

    Science.gov (United States)

    Vacher, Corinne; Kossler, Tanya M; Hochberg, Michael E; Weis, Arthur E

    2011-02-03

    Like conventional crops, some GM cultivars may readily hybridize with their wild or weedy relatives. The progressive introgression of transgenes into wild or weedy populations thus appears inevitable, and we are now faced with the challenge of determining the possible evolutionary effects of these transgenes. The aim of this study was to gain insight into the impact of interspecific hybridization between transgenic plants and weedy relatives on the evolution of the weedy phenotype. Experimental populations of weedy birdseed rape (Brassica rapa) and transgenic rapeseed (B. napus) were grown under glasshouse conditions. Hybridization opportunities with transgenic plants and phenotypic traits (including phenological, morphological and reproductive traits) were measured for each weedy individual. We show that weedy individuals that flowered later and for longer periods were more likely to receive transgenic pollen from crops and weed × crop hybrids. Because stem diameter is correlated with flowering time, plants with wider stems were also more likely to be pollinated by transgenic plants. We also show that the weedy plants with the highest probability of hybridization had the lowest fecundity. Our results suggest that weeds flowering late and for long periods are less fit because they have a higher probability of hybridizing with crops or weed × crop hybrids. This may result in counter-selection against this subset of weed phenotypes, and a shorter earlier flowering period. It is noteworthy that this potential evolution in flowering time does not depend on the presence of the transgene in the crop. Evolution in flowering time may even be counter-balanced by positive selection acting on the transgene if the latter was positively associated with maternal genes promoting late flowering and long flowering periods. Unfortunately, we could not verify this association in the present experiment.

  9. Folates in plants: research advances and progress in crop biofortification

    Science.gov (United States)

    Gorelova, Vera; Ambach, Lars; Rébeillé, Fabrice; Stove, Christophe; Van Der Straeten, Dominique

    2017-03-01

    Folates, also known as B9 vitamins, serve as donors and acceptors in one-carbon (C1) transfer reactions. The latter are involved in synthesis of many important biomolecules, such as amino acids, nucleic acids and vitamin B5. Folates also play a central role in the methyl cycle that provides one-carbon groups for methylation reactions. The important functions fulfilled by folates make them essential in all living organisms. Plants, being able to synthesize folates de novo, serve as an excellent dietary source of folates for animals that lack the respective biosynthetic pathway. Unfortunately, the most important staple crops such as rice, potato and maize are rather poor sources of folates. Insufficient folate consumption is known to cause severe developmental disorders in humans. Two approaches are employed to fight folate deficiency: pharmacological supplementation in the form of folate pills and biofortification of staple crops. As the former approach is considered rather costly for the major part of the world population, biofortification of staple crops is viewed as a decent alternative in the struggle against folate deficiency. Therefore strategies, challenges and recent progress of folate enhancement in plants will be addressed in this review. Apart from the ever-growing need for the enhancement of nutritional quality of crops, the world population faces climate change catastrophes or environmental stresses, such as elevated temperatures, drought, salinity that severely affect growth and productivity of crops. Due to immense diversity of their biochemical functions, folates take part in virtually every aspect of plant physiology. Any disturbance to the plant folate metabolism leads to severe growth inhibition and, as a consequence, to a lower productivity. Whereas today’s knowledge of folate biochemistry can be considered very profound, evidence on the physiological roles of folates in plants only starts to emerge. In the current review we will discuss the

  10. Using genetically modified tomato crop plants with purple leaves for absolute weed/crop classification.

    Science.gov (United States)

    Lati, Ran N; Filin, Sagi; Aly, Radi; Lande, Tal; Levin, Ilan; Eizenberg, Hanan

    2014-07-01

    Weed/crop classification is considered the main problem in developing precise weed-management methodologies, because both crops and weeds share similar hues. Great effort has been invested in the development of classification models, most based on expensive sensors and complicated algorithms. However, satisfactory results are not consistently obtained due to imaging conditions in the field. We report on an innovative approach that combines advances in genetic engineering and robust image-processing methods to detect weeds and distinguish them from crop plants by manipulating the crop's leaf color. We demonstrate this on genetically modified tomato (germplasm AN-113) which expresses a purple leaf color. An autonomous weed/crop classification is performed using an invariant-hue transformation that is applied to images acquired by a standard consumer camera (visible wavelength) and handles variations in illumination intensities. The integration of these methodologies is simple and effective, and classification results were accurate and stable under a wide range of imaging conditions. Using this approach, we simplify the most complicated stage in image-based weed/crop classification models. © 2013 Society of Chemical Industry.

  11. Large SNP arrays for genotyping in crop plants

    Indian Academy of Sciences (India)

    For a number of important crop plants, SNP markers are now being used to design genotyping arrays containing thousands of markers spread over the entire genome and to analyse large numbers of samples. In this article, we discuss aspects that should be considered during the design of such large genotyping arrays and ...

  12. Association of non-heterocystous cyanobacteria with crop plants

    NARCIS (Netherlands)

    Ahmed, M.; Stal, L.J.; Hasnain, S.

    2010-01-01

    Cyanobacteria have the ability to form associations with organisms from all domains of life, notably with plants, which they provide with fixed nitrogen, among other substances. This study was aimed at developing artificial associations between non-heterocystous cyanobacteria and selected crop

  13. PLANT INCORPORATED PROTECTANT CROP MONITORING USING REMOTE SENSING

    Science.gov (United States)

    The extent of past and anticipated plantings of transgenic corn in the United States requires a new approach to monitor this important crop for the development of pest resistance. Remote sensing by aerial and/or satellite images may provide a method of identifying transgenic pest...

  14. Climate change effects on plant growth, crop yield and livestock

    NARCIS (Netherlands)

    Rötter, R.P.; Geijn, van de S.C.

    1999-01-01

    A review is given of the state of knowledge in the field of assessing climate change impacts on agricultural crops and livestock. Starting from the basic processes controlling plant growth and development, the possible impacts and interactions of climatic and other biophysical variables in different

  15. Models for navigating biological complexity in breeding improved crop plants

    NARCIS (Netherlands)

    Hammer, G.; Cooper, M.; Tardieu, F.; Welch, S.; Walsh, B.; Eeuwijk, van F.A.; Chapman, S.; Podlich, D.

    2006-01-01

    Progress in breeding higher-yielding crop plants would be greatly accelerated if the phenotypic consequences of making changes to the genetic makeup of an organism could be reliably predicted. Developing a predictive capacity that scales from genotype to phenotype is impeded by biological

  16. influence of cassava planting patterns and pruning methods on crop ...

    African Journals Online (AJOL)

    2003-12-03

    Dec 3, 2003 ... Field experiments were conducted at the University of Ibadan, Ni geria on the effect ofcassava (Manihot esculenta. Crantz) planting pattern and pruning methods on eassava yield and yield ofassociated crops, namely, maize (Zea mays L. ), melon (Colocynthis vulgaris L.) and cowpea ( Vigna unguiculaia) in ...

  17. Animal plant warfare and secondary metabolite evolution

    OpenAIRE

    Wöll, Steffen; Kim, Sun Hee; Greten, Henry Johannes; Efferth, Thomas

    2013-01-01

    Abstract The long-lasting discussion, why plants produce secondary metabolites, which are pharmacologically and toxicologically active towards mammals traces back to the eminent role of medicinal plants in the millennia-old history of manhood. In recent years, the concept of an animal plant warfare emerged, which focused on the co-evolution between plants and herbivores. As a reaction to herbivory, plants developed mechanical defenses such as thorns and hard shells, which paved the way for ad...

  18. Crop management in greenhouses: adapting the growth conditions to the plant needs or adapting the plant to the growth conditions?

    NARCIS (Netherlands)

    Marcelis, L.F.M.; Pascale, De S.

    2009-01-01

    Strategies for improving greenhouse crop production should target both developing advanced technological systems and designing improved plants. Based on greenhouse experiments, crop models and biotechnological tools, this paper will discuss the physiology of plant-greenhouse interactions. It is

  19. Quantifying the effect of crop spatial arrangement on weed suppression using functional-structural plant modelling

    NARCIS (Netherlands)

    Evers, Jochem B.; Bastiaans, Lammert

    2016-01-01

    Suppression of weed growth in a crop canopy can be enhanced by improving crop competitiveness. One way to achieve this is by modifying the crop planting pattern. In this study, we addressed the question to what extent a uniform planting pattern increases the ability of a crop to compete with weed

  20. Transfer of engineered genes from crop to wild plants

    DEFF Research Database (Denmark)

    Bagger Jørgensen, Rikke; Hauser, T.P.; Mikkelsen, T.R.

    1996-01-01

    The escape of engineered genes - genes inserted using recombinant DNA techniques - from cultivated plants to wild or weedy relatives has raised concern about possible risks to the environment or to health. The media have added considerably to public concern by suggesting that such gene escape...... is a new and rather unexpected phenomenon. However, transfer of engineered genes between plants is not at-all surprising, because it is mediated by exactly the same mechanisms as those responsible for transferring endogenous plant genes: it takes place by sexual crosses, with pollen as the carrier......, Such sexual reproduction has been the basis for breeding almost all crops....

  1. Quantifying the effect of crop spatial arrangement on weed suppression using functional-structural plant modelling.

    Science.gov (United States)

    Evers, Jochem B; Bastiaans, Lammert

    2016-05-01

    Suppression of weed growth in a crop canopy can be enhanced by improving crop competitiveness. One way to achieve this is by modifying the crop planting pattern. In this study, we addressed the question to what extent a uniform planting pattern increases the ability of a crop to compete with weed plants for light compared to a random and a row planting pattern, and how this ability relates to crop and weed plant density as well as the relative time of emergence of the weed. To this end, we adopted the functional-structural plant modelling approach which allowed us to explicitly include the 3D spatial configuration of the crop-weed canopy and to simulate intra- and interspecific competition between individual plants for light. Based on results of simulated leaf area development, canopy photosynthesis and biomass growth of the crop, we conclude that differences between planting pattern were small, particularly if compared to the effects of relative time of emergence of the weed, weed density and crop density. Nevertheless, analysis of simulated weed biomass demonstrated that a uniform planting of the crop improved the weed-suppression ability of the crop canopy. Differences in weed suppressiveness between planting patterns were largest with weed emergence before crop emergence, when the suppressive effect of the crop was only marginal. With simultaneous emergence a uniform planting pattern was 8 and 15 % more competitive than a row and a random planting pattern, respectively. When weed emergence occurred after crop emergence, differences between crop planting patterns further decreased as crop canopy closure was reached early on regardless of planting pattern. We furthermore conclude that our modelling approach provides promising avenues to further explore crop-weed interactions and aid in the design of crop management strategies that aim at improving crop competitiveness with weeds.

  2. Beans (Phaseolus ssp.) as a Model for Understanding Crop Evolution

    Science.gov (United States)

    Bitocchi, Elena; Rau, Domenico; Bellucci, Elisa; Rodriguez, Monica; Murgia, Maria L.; Gioia, Tania; Santo, Debora; Nanni, Laura; Attene, Giovanna; Papa, Roberto

    2017-01-01

    Here, we aim to provide a comprehensive and up-to-date overview of the most significant outcomes in the literature regarding the origin of Phaseolus genus, the geographical distribution of the wild species, the domestication process, and the wide spread out of the centers of origin. Phaseolus can be considered as a unique model for the study of crop evolution, and in particular, for an understanding of the convergent phenotypic evolution that occurred under domestication. The almost unique situation that characterizes the Phaseolus genus is that five of its ∼70 species have been domesticated (i.e., Phaseolus vulgaris, P. coccineus, P. dumosus, P. acutifolius, and P. lunatus), and in addition, for P. vulgaris and P. lunatus, the wild forms are distributed in both Mesoamerica and South America, where at least two independent and isolated episodes of domestication occurred. Thus, at least seven independent domestication events occurred, which provides the possibility to unravel the genetic basis of the domestication process not only among species of the same genus, but also between gene pools within the same species. Along with this, other interesting features makes Phaseolus crops very useful in the study of evolution, including: (i) their recent divergence, and the high level of collinearity and synteny among their genomes; (ii) their different breeding systems and life history traits, from annual and autogamous, to perennial and allogamous; and (iii) their adaptation to different environments, not only in their centers of origin, but also out of the Americas, following their introduction and wide spread through different countries. In particular for P. vulgaris this resulted in the breaking of the spatial isolation of the Mesoamerican and Andean gene pools, which allowed spontaneous hybridization, thus increasing of the possibility of novel genotypes and phenotypes. This knowledge that is associated to the genetic resources that have been conserved ex situ and in

  3. The first crop plant genetically engineered to release an insect pheromone for defence

    National Research Council Canada - National Science Library

    Bruce, Toby J A; Aradottir, Gudbjorg I; Smart, Lesley E; Martin, Janet L; Caulfield, John C; Doherty, Angela; Sparks, Caroline A; Woodcock, Christine M; Birkett, Michael A; Napier, Johnathan A; Jones, Huw D; Pickett, John A

    2015-01-01

    Insect pheromones offer potential for managing pests of crop plants. Volatility and instability are problems for deployment in agriculture but could be solved by expressing genes for the biosynthesis of pheromones in the crop plants...

  4. Comparative genomics of grass EST libraries reveals previously uncharacterized splicing events in crop plants.

    Science.gov (United States)

    Chuang, Trees-Juen; Yang, Min-Yu; Lin, Chuang-Chieh; Hsieh, Ping-Hung; Hung, Li-Yuan

    2015-02-05

    for determining whether the identified exons were alternatively spliced. This study not only presents an effective in silico strategy for the improvement of plant annotations, but also provides further insights into the role of AS events in the evolution and domestication of crop plants. ExonFinder and the novel exons/ASVs identified are publicly accessible at http://exonfinder.sourceforge.net/ .

  5. Distinguishing succulent plants from crop and woody plants

    Science.gov (United States)

    Gausman, H. W.; Escobar, D. E.; Everitt, J. H.; Richardson, A. J.; Rodriguez, R. R.

    1978-01-01

    We compared laboratory spectrophotometrically measured leaf reflectances of six succulents (peperomia, possum-grape, prickly pear, spiderwort, Texas tuberose, wolfberry) with those of four nonsucculents (cenizo, honey mesquite, cotton, sugarcane) for plant species discrimination. Succulents (average leaf water content of 92.2 percent) could be distinguished from nonsucculents (average leaf water content of 71.2 percent) within the near-infrared water absorption waveband (1.35 to 2.5 microns). This was substantiated by field spectrophotometric reflectances of plant canopies. Sensor bands encompassing either the 1.6- or 2.2-wavelengths may be useful to distinguish succulent from nonsucculent plant species.

  6. Role of soil, crop debris, and a plant pathogen in Salmonella enterica contamination of tomato plants.

    Directory of Open Access Journals (Sweden)

    Jeri D Barak

    Full Text Available BACKGROUND: In the U.S., tomatoes have become the most implicated vehicle for produce-associated Salmonellosis with 12 outbreaks since 1998. Although unconfirmed, trace backs suggest pre-harvest contamination with Salmonella enterica. Routes of tomato crop contamination by S. enterica in the absence of direct artificial inoculation have not been investigated. METHODOLOGY/PRINCIPAL FINDINGS: This work examined the role of contaminated soil, the potential for crop debris to act as inoculum from one crop to the next, and any interaction between the seedbourne plant pathogen Xanthomonas campestris pv. vesicatoria and S. enterica on tomato plants. Our results show S. enterica can survive for up to six weeks in fallow soil with the ability to contaminate tomato plants. We found S. enterica can contaminate a subsequent crop via crop debris; however a fallow period between crop incorporation and subsequent seeding can affect contamination patterns. Throughout these studies, populations of S. enterica declined over time and there was no bacterial growth in either the phyllosphere or rhizoplane. The presence of X. campestris pv. vesicatoria on co-colonized tomato plants had no effect on the incidence of S. enterica tomato phyllosphere contamination. However, growth of S. enterica in the tomato phyllosphere occurred on co-colonized plants in the absence of plant disease. CONCLUSIONS/SIGNIFICANCE: S. enterica contaminated soil can lead to contamination of the tomato phyllosphere. A six week lag period between soil contamination and tomato seeding did not deter subsequent crop contamination. In the absence of plant disease, presence of the bacterial plant pathogen, X. campestris pv. vesicatoria was beneficial to S. enterica allowing multiplication of the human pathogen population. Any event leading to soil contamination with S. enterica could pose a public health risk with subsequent tomato production, especially in areas prone to bacterial spot disease.

  7. Coping mechanisms for crop plants in drought-prone environments.

    Science.gov (United States)

    Neumann, Peter M

    2008-05-01

    Drought is a major limitation to plant productivity. Various options are available for increasing water availability and sustaining growth of crop plants in drought-prone environments. After a general introduction to the problems of water availability, this review focuses on a critical evaluation of recent progress in unravelling mechanisms for modifying plant growth responses to drought. Investigations of key regulatory mechanisms integrating plant growth responses to water deficits at the whole-organism, cellular and genomic levels continue to provide novel and exiting research findings. For example, recent reports contradict the widespread conception that root-derived abscisic acid is necessarily involved in signalling for stomatal and shoot-growth responses to soil water deficits. The findings bring into question the theoretical basis for alternate-side root-irrigation techniques. Similarly, recent reports indicate that increased ABA production or increased aquaporin expression did not lead to improved drought resistance. Other reports have concerned key genes and proteins involved in regulation of flowering (FT), vegetative growth (DELLA), leaf senescence (IPT) and desiccation tolerance (LEA). Introgression of such genes, with suitable promoters, can greatly impact on whole-plant responses to drought. Further developments could facilitate the introduction by breeders of new crop varieties with growth physiologies tailored to improved field performance under drought. Parallel efforts to encourage the introduction of supplementary irrigation with water made available by improved conservation measures and by sea- or brackish-water desalination, will probably provide comprehensive solutions to coping with drought-prone environments.

  8. Heterochronic genes in plant evolution and development

    Directory of Open Access Journals (Sweden)

    Koen eGeuten

    2013-09-01

    Full Text Available Evolution of morphology includes evolutionary shifts of developmental processes in space or in time. Heterochronic evolution is defined as a temporal shift. The concept of heterochrony has been very rewarding to investigators of both animal and plant developmental evolution, because it has strong explanatory power when trying to understand morphological diversity. While for animals, extensive literature on heterochrony developed along with the field of evolution of development, in plants the concept has been applied less often and is less elaborately developed. Yet novel genetic findings highlight heterochrony as a developmental and evolutionary process in plants. Similar to what has been found for the worm Caenorhabditis, a heterochronic gene pathway controlling developmental timing has been elucidated in flowering plants. Two antagonistic microRNA’s miR156 and miR172 target two gene families of transcription factors, SQUAMOSA PROMOTOR BINDING PROTEIN LIKE and APETALA2-like respectively. In this review, we propose that this finding now allows the molecular investigation of cases of heterochronic evolution in plants. We illustrate this point by examining microRNA expression patterns in the Antirrhinum majus incomposita and choripetala heterochronic mutants. Some of the more beautiful putative cases of heterochronic evolution can be found outside flowering plants, but little is known about the extent of conservation of this flowering plant pathway in other land plants. We show that the expression of an APETALA2-like gene decreases with age in a fern species. This contributes to the idea that ferns share some heterochronic gene functions with flowering plants.

  9. Time interval between cover crop termination and planting influences corn seedling disease, plant growth, and yield

    Science.gov (United States)

    Experiments were established in controlled and field environment to evaluate the effect of time intervals between cereal rye cover crop termination and corn planting on corn seedling disease, corn growth, and grain yield in 2014 and 2015. Rye termination dates ranged from 25 days before planting (DB...

  10. Scale and Complexity in Plant Systems Research : Gene-Plant-Crop Relations

    NARCIS (Netherlands)

    Spiertz, J.H.J.; Struik, P.C.; Laar, van H.H.

    2007-01-01

    This book presents and discusses new directions in plant systems research to bridge knowledge from the gene to plant, crop and agro-ecosystem level and to assist in solving problems in production ecology and resource use by identifying and applying new research methods. Functional genomics, systems

  11. The International Breeder's Rights System and Crop Plant Innovation.

    Science.gov (United States)

    Barton, J H

    1982-06-04

    Legal arrangements governing a plant breeder's intellectual property rights to his inventions are likely to affect the future of crop research. Such systems, although controversial, are probably currently desirable for the developed world. The new genetic technologies may change this judgment, and certainly require redefinition of the lines between plant patents and regular patents. Several safeguards, present in the United States breeder's rights law, should be applied more broadly. A new safeguard-of ensuring that material be entered into germplasm banks-should be applied everywhere. For the developing world, the desirability of a plant patent system is much less clear; new agreements may be desirable to ensure the free flow and collection of germplasm.

  12. Plant growth promotion in cereal and leguminous agricultural important plants: from microorganism capacities to crop production.

    Science.gov (United States)

    Pérez-Montaño, F; Alías-Villegas, C; Bellogín, R A; del Cerro, P; Espuny, M R; Jiménez-Guerrero, I; López-Baena, F J; Ollero, F J; Cubo, T

    2014-01-01

    Plant growth-promoting rhizobacteria (PGPR) are free-living bacteria which actively colonize plant roots, exerting beneficial effects on plant development. The PGPR may (i) promote the plant growth either by using their own metabolism (solubilizing phosphates, producing hormones or fixing nitrogen) or directly affecting the plant metabolism (increasing the uptake of water and minerals), enhancing root development, increasing the enzymatic activity of the plant or "helping" other beneficial microorganisms to enhance their action on the plants; (ii) or may promote the plant growth by suppressing plant pathogens. These abilities are of great agriculture importance in terms of improving soil fertility and crop yield, thus reducing the negative impact of chemical fertilizers on the environment. The progress in the last decade in using PGPR in a variety of plants (maize, rice, wheat, soybean and bean) along with their mechanism of action are summarized and discussed here. Copyright © 2013 Elsevier GmbH. All rights reserved.

  13. Genetic engineering of crop plants for fungal resistance: role of antifungal genes.

    Science.gov (United States)

    Ceasar, S Antony; Ignacimuthu, S

    2012-06-01

    Fungal diseases damage crop plants and affect agricultural production. Transgenic plants have been produced by inserting antifungal genes to confer resistance against fungal pathogens. Genes of fungal cell wall-degrading enzymes, such as chitinase and glucanase, are frequently used to produce fungal-resistant transgenic crop plants. In this review, we summarize the details of various transformation studies to develop fungal resistance in crop plants.

  14. Plant defense against herbivorous pests: exploiting resistance and tolerance traits for sustainable crop protection

    Directory of Open Access Journals (Sweden)

    Carolyn Mitchell

    2016-07-01

    Full Text Available Interactions between plants and insect herbivores are important determinants of plant productivity in managed and natural vegetation. In response to attack, plants have evolved a range of defenses to reduce the threat of injury and loss of productivity. Crop losses from damage caused by arthropod pests can exceed 15% annually. Crop domestication and selection for improved yield and quality can alter the defensive capability of the crop, increasing reliance on artificial crop protection. Sustainable agriculture, however, depends on reduced chemical inputs. There is an urgent need, therefore, to identify plant defensive traits for crop improvement. Plant defense can be divided into resistance and tolerance strategies. Plant traits that confer herbivore resistance typically prevent or reduce herbivore damage through expression of traits that deter pests from settling, attaching to surfaces, feeding and reproducing, or that reduce palatability. Plant tolerance of herbivory involves expression of traits that limit the negative impact of herbivore damage on productivity and yield. Identifying the defensive traits expressed by plants to deter herbivores or limit herbivore damage, and understanding the underlying defense mechanisms, is crucial for crop scientists to exploit plant defensive traits in crop breeding. In this review, we assess the traits and mechanisms underpinning herbivore resistance and tolerance, and conclude that physical defense traits, plant vigor and herbivore-induced plant volatiles show considerable utility in pest control, along with mixed species crops. We highlight emerging approaches for accelerating the identification of plant defensive traits and facilitating their deployment to improve the future sustainability of crop protection.

  15. Genomics and Evolution in Traditional Medicinal Plants: Road to a Healthier Life

    Science.gov (United States)

    Hao, Da-Cheng; Xiao, Pei-Gen

    2015-01-01

    Medicinal plants have long been utilized in traditional medicine and ethnomedicine worldwide. This review presents a glimpse of the current status of and future trends in medicinal plant genomics, evolution, and phylogeny. These dynamic fields are at the intersection of phytochemistry and plant biology and are concerned with the evolution mechanisms and systematics of medicinal plant genomes, origin and evolution of the plant genotype and metabolic phenotype, interaction between medicinal plant genomes and their environment, the correlation between genomic diversity and metabolite diversity, and so on. Use of the emerging high-end genomic technologies can be expanded from crop plants to traditional medicinal plants, in order to expedite medicinal plant breeding and transform them into living factories of medicinal compounds. The utility of molecular phylogeny and phylogenomics in predicting chemodiversity and bioprospecting is also highlighted within the context of natural-product-based drug discovery and development. Representative case studies of medicinal plant genome, phylogeny, and evolution are summarized to exemplify the expansion of knowledge pedigree and the paradigm shift to the omics-based approaches, which update our awareness about plant genome evolution and enable the molecular breeding of medicinal plants and the sustainable utilization of plant pharmaceutical resources. PMID:26461812

  16. Genomics and Evolution in Traditional Medicinal Plants: Road to a Healthier Life.

    Science.gov (United States)

    Hao, Da-Cheng; Xiao, Pei-Gen

    2015-01-01

    Medicinal plants have long been utilized in traditional medicine and ethnomedicine worldwide. This review presents a glimpse of the current status of and future trends in medicinal plant genomics, evolution, and phylogeny. These dynamic fields are at the intersection of phytochemistry and plant biology and are concerned with the evolution mechanisms and systematics of medicinal plant genomes, origin and evolution of the plant genotype and metabolic phenotype, interaction between medicinal plant genomes and their environment, the correlation between genomic diversity and metabolite diversity, and so on. Use of the emerging high-end genomic technologies can be expanded from crop plants to traditional medicinal plants, in order to expedite medicinal plant breeding and transform them into living factories of medicinal compounds. The utility of molecular phylogeny and phylogenomics in predicting chemodiversity and bioprospecting is also highlighted within the context of natural-product-based drug discovery and development. Representative case studies of medicinal plant genome, phylogeny, and evolution are summarized to exemplify the expansion of knowledge pedigree and the paradigm shift to the omics-based approaches, which update our awareness about plant genome evolution and enable the molecular breeding of medicinal plants and the sustainable utilization of plant pharmaceutical resources.

  17. Genome Evolution of Plant-Parasitic Nematodes.

    Science.gov (United States)

    Kikuchi, Taisei; Eves-van den Akker, Sebastian; Jones, John T

    2017-08-04

    Plant parasitism has evolved independently on at least four separate occasions in the phylum Nematoda. The application of next-generation sequencing (NGS) to plant-parasitic nematodes has allowed a wide range of genome- or transcriptome-level comparisons, and these have identified genome adaptations that enable parasitism of plants. Current genome data suggest that horizontal gene transfer, gene family expansions, evolution of new genes that mediate interactions with the host, and parasitism-specific gene regulation are important adaptations that allow nematodes to parasitize plants. Sequencing of a larger number of nematode genomes, including plant parasites that show different modes of parasitism or that have evolved in currently unsampled clades, and using free-living taxa as comparators would allow more detailed analysis and a better understanding of the organization of key genes within the genomes. This would facilitate a more complete understanding of the way in which parasitism has shaped the genomes of plant-parasitic nematodes.

  18. Microorganism and filamentous fungi drive evolution of plant synapses

    OpenAIRE

    Baluška, František; Mancuso, Stefano

    2013-01-01

    In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and s...

  19. Opportunities for improving phosphorus-use efficiency in crop plants.

    Science.gov (United States)

    Veneklaas, Erik J; Lambers, Hans; Bragg, Jason; Finnegan, Patrick M; Lovelock, Catherine E; Plaxton, William C; Price, Charles A; Scheible, Wolf-Rüdiger; Shane, Michael W; White, Philip J; Raven, John A

    2012-07-01

    Limitation of grain crop productivity by phosphorus (P) is widespread and will probably increase in the future. Enhanced P efficiency can be achieved by improved uptake of phosphate from soil (P-acquisition efficiency) and by improved productivity per unit P taken up (P-use efficiency). This review focuses on improved P-use efficiency, which can be achieved by plants that have overall lower P concentrations, and by optimal distribution and redistribution of P in the plant allowing maximum growth and biomass allocation to harvestable plant parts. Significant decreases in plant P pools may be possible, for example, through reductions of superfluous ribosomal RNA and replacement of phospholipids by sulfolipids and galactolipids. Improvements in P distribution within the plant may be possible by increased remobilization from tissues that no longer need it (e.g. senescing leaves) and reduced partitioning of P to developing grains. Such changes would prolong and enhance the productive use of P in photosynthesis and have nutritional and environmental benefits. Research considering physiological, metabolic, molecular biological, genetic and phylogenetic aspects of P-use efficiency is urgently needed to allow significant progress to be made in our understanding of this complex trait. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  20. Transgenerational Defense Priming for Crop Protection against Plant Pathogens: A Hypothesis.

    Science.gov (United States)

    Ramírez-Carrasco, Gabriela; Martínez-Aguilar, Keren; Alvarez-Venegas, Raúl

    2017-01-01

    Throughout evolution, plants have developed diverse mechanisms of defense that "prime" their innate immune system for more robust and active induction of defense responses against different types of stress. Nowadays there are numerous reports concerning the molecular bases of priming, as well as the generational priming mechanisms. Information concerning transgenerational priming, however, remains deficient. Some reports have indicated, nonetheless, that the priming status of a plant can be inherited to its offspring. Here, we show that the priming agent β-aminobutyric acid induced resistance to Pseudomonas syringae pv. phaseolicola infection in the common bean (Phaseolus vulgaris L.) We have analyzed the transgenerational patterns of gene expression of the PvPR1 gene (Phaseolus vulgaris PR1), a highly responsive gene to priming, and show that a transgenerational priming response against pathogen attack can last for at least two generations. We hypothesize that a defense-resistant phenotype and easily identifiable, generational and transgenerational, "primed patterns" of gene expression are excellent indicators of the priming response in crop plants. Furthermore, we propose here that modern plant breeding methods and crop improvement efforts must include the use of elicitors to prime induced resistance in the field and, above all, to select for induced heritable states in progeny that is primed for defense.

  1. Transgenerational Defense Priming for Crop Protection against Plant Pathogens: A Hypothesis

    Directory of Open Access Journals (Sweden)

    Gabriela Ramírez-Carrasco

    2017-05-01

    Full Text Available Throughout evolution, plants have developed diverse mechanisms of defense that “prime” their innate immune system for more robust and active induction of defense responses against different types of stress. Nowadays there are numerous reports concerning the molecular bases of priming, as well as the generational priming mechanisms. Information concerning transgenerational priming, however, remains deficient. Some reports have indicated, nonetheless, that the priming status of a plant can be inherited to its offspring. Here, we show that the priming agent β-aminobutyric acid induced resistance to Pseudomonas syringae pv. phaseolicola infection in the common bean (Phaseolus vulgaris L. We have analyzed the transgenerational patterns of gene expression of the PvPR1 gene (Phaseolus vulgaris PR1, a highly responsive gene to priming, and show that a transgenerational priming response against pathogen attack can last for at least two generations. We hypothesize that a defense-resistant phenotype and easily identifiable, generational and transgenerational, “primed patterns” of gene expression are excellent indicators of the priming response in crop plants. Furthermore, we propose here that modern plant breeding methods and crop improvement efforts must include the use of elicitors to prime induced resistance in the field and, above all, to select for induced heritable states in progeny that is primed for defense.

  2. Molecular evolution of candidate genes for crop-related traits in sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Mandel, Jennifer R; McAssey, Edward V; Nambeesan, Savithri; Garcia-Navarro, Elena; Burke, John M

    2014-01-01

    Evolutionary analyses aimed at detecting the molecular signature of selection during crop domestication and/or improvement can be used to identify genes or genomic regions of likely agronomic importance. Here, we describe the DNA sequence-based characterization of a pool of candidate genes for crop-related traits in sunflower. These genes, which were identified based on homology to genes of known effect in other study systems, were initially sequenced from a panel of improved lines. All genes that exhibited a paucity of sequence diversity, consistent with the possible effects of selection during the evolution of cultivated sunflower, were then sequenced from a panel of wild sunflower accessions an outgroup. These data enabled formal tests for the effects of selection in shaping sequence diversity at these loci. When selection was detected, we further sequenced these genes from a panel of primitive landraces, thereby allowing us to investigate the likely timing of selection (i.e., domestication vs. improvement). We ultimately identified seven genes that exhibited the signature of positive selection during either domestication or improvement. Genetic mapping of a subset of these genes revealed co-localization between candidates for genes involved in the determination of flowering time, seed germination, plant growth/development, and branching and QTL that were previously identified for these traits in cultivated × wild sunflower mapping populations.

  3. Assessment of the phytoextraction potential of high biomass crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Allica, Javier [NEIKER-tecnalia, Basque Institute of Agricultural Research and Development, c/Berreaga 1, E-48160 Derio (Spain); Becerril, Jose M. [Department of Plant Biology and Ecology, University of the Basque Country, P.O. Box 644, E-48080 Bilbao (Spain); Garbisu, Carlos [NEIKER-tecnalia, Basque Institute of Agricultural Research and Development, c/Berreaga 1, E-48160 Derio (Spain)], E-mail: cgarbisu@neiker.net

    2008-03-15

    A hydroponic screening method was used to identify high biomass crop plants with the ability to accumulate metals. Highest values of shoot accumulation were found in maize cv. Ranchero, rapeseed cv. Karat, and cardoon cv. Peralta for Pb (18 753 mg kg{sup -1}), Zn (10 916 mg kg{sup -1}), and Cd (242 mg kg{sup -1}), respectively. Subsequently, we tested the potential of these three cultivars for the phytoextraction of a metal spiked compost, finding out that, in cardoon and maize plants, increasing Zn and Cd concentrations led to lower values of root and shoot DW. By contrast, rapeseed shoot growth was not significantly affected by Cd concentration. Finally, a metal polluted soil was used to check these cultivars' phytoextraction capacity. Although the soil was phytotoxic enough to prevent the growth of cardoon and rapeseed plants, maize plants phytoextracted 3.7 mg Zn pot{sup -1}. We concluded that the phytoextraction performance of cultivars varies depending on the screening method used. - The phytoextraction performance of cultivars varies significantly depending on the screening method used.

  4. Not all GMOs are crop plants: non-plant GMO applications in agriculture.

    Science.gov (United States)

    Hokanson, K E; Dawson, W O; Handler, A M; Schetelig, M F; St Leger, R J

    2014-12-01

    Since tools of modern biotechnology have become available, the most commonly applied and often discussed genetically modified organisms are genetically modified crop plants, although genetic engineering is also being used successfully in organisms other than plants, including bacteria, fungi, insects, and viruses. Many of these organisms, as with crop plants, are being engineered for applications in agriculture, to control plant insect pests or diseases. This paper reviews the genetically modified non-plant organisms that have been the subject of permit approvals for environmental release by the United States Department of Agriculture/Animal and Plant Health Inspection Service since the US began regulating genetically modified organisms. This is an indication of the breadth and progress of research in the area of non-plant genetically modified organisms. This review includes three examples of promising research on non-plant genetically modified organisms for application in agriculture: (1) insects for insect pest control using improved vector systems; (2) fungal pathogens of insects to control insect pests; and (3) virus for use as transient-expression vectors for disease control in plants.

  5. Understanding and engineering beneficial plant-microbe interactions: plant growth promotion in energy crops.

    Science.gov (United States)

    Farrar, Kerrie; Bryant, David; Cope-Selby, Naomi

    2014-12-01

    Plant production systems globally must be optimized to produce stable high yields from limited land under changing and variable climates. Demands for food, animal feed, and feedstocks for bioenergy and biorefining applications, are increasing with population growth, urbanization and affluence. Low-input, sustainable, alternatives to petrochemical-derived fertilizers and pesticides are required to reduce input costs and maintain or increase yields, with potential biological solutions having an important role to play. In contrast to crops that have been bred for food, many bioenergy crops are largely undomesticated, and so there is an opportunity to harness beneficial plant-microbe relationships which may have been inadvertently lost through intensive crop breeding. Plant-microbe interactions span a wide range of relationships in which one or both of the organisms may have a beneficial, neutral or negative effect on the other partner. A relatively small number of beneficial plant-microbe interactions are well understood and already exploited; however, others remain understudied and represent an untapped reservoir for optimizing plant production. There may be near-term applications for bacterial strains as microbial biopesticides and biofertilizers to increase biomass yield from energy crops grown on land unsuitable for food production. Longer term aims involve the design of synthetic genetic circuits within and between the host and microbes to optimize plant production. A highly exciting prospect is that endosymbionts comprise a unique resource of reduced complexity microbial genomes with adaptive traits of great interest for a wide variety of applications. © 2014 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  6. Evolution of the land plant Exocyst complexes

    Directory of Open Access Journals (Sweden)

    Fatima eCvrckova

    2012-07-01

    Full Text Available Exocyst is an evolutionarily conserved vesicle tethering complex functioning especially in the last stage of exocytosis. Homologs of its eight canonical subunits -Sec3, Sec5, Sec6, Sec8, Sec10, Sec15, Exo70 and Exo84 - were found also in higher plants and confirmed to form complexes in vivo, and to participate in cell growth including polarized expansion of pollen tubes and root hairs. Here we present results of a phylogenetic study of land plant exocyst subunits encoded by a selection of completely sequenced genomes representing a variety of plant, mostly angiosperm, lineages. According to their evolution histories, plant exocyst subunits can be divided into several groups. The core subunits Sec6, Sec8 and Sec10, together with Sec3 and Sec5, underwent few, if any fixed duplications in the tracheophytes (though they did amplify in the moss Physcomitrella patens, while others form larger families, with the number of paralogs ranging typically from two to eight per genome (Sec15, Exo84 to several dozens per genome (Exo70. Most of the diversity, which can be in some cases traced down to the origins of land plants, can be attributed to the peripheral subunits Exo84 and, in particular, Exo70. As predicted previously, early land plants (including possibly also the Rhyniophytes encoded three basal Exo70 paralogs which further diversified in the course of land plant evolution. Our results imply that plants do not have a single "Exocyst complex" – instead, they appear to possess a diversity of exocyst variants unparalleled among other organisms studied so far. This feature might perhaps be directly related to the demands of building and maintenance of the complicated and spatially diverse structures of the endomembranes and cell surfaces in multicellular land plants.

  7. Evolution of plant P-type ATPases

    Directory of Open Access Journals (Sweden)

    Christian N.S. Pedersen

    2012-02-01

    Full Text Available Five organisms having completely sequenced genomes and belonging to all major branches of green plants (Viridiplantae were analyzed with respect to their content of P-type ATPases encoding genes. These were the chlorophytes Ostreococcus tauria and Chlamydomonas reinhardtii, and the streptophytes Physcomitrella patens (a moss, Selaginella moellendorffii (a primitive vascular plant, and Arabidopsis thaliana (a model flowering plant. Each organism contained sequences for all five subfamilies of P-type ATPases. Our analysis demonstrates when specific subgroups of P-type ATPases disappeared in the evolution of Angiosperms. Na/K-pump related P2C ATPases were lost with the evolution of streptophytes whereas Na+ or K+ pumping P2D ATPases and secretory pathway Ca2+-ATPases remained until mosses. An N-terminally located calmodulin binding domain in P2B ATPases can only be detected in pumps from Streptophytae, whereas, like in animals, a C-terminally localized calmodulin binding domain might be present in chlorophyte P2B Ca2+-ATPases. Chlorophyte genomes encode P3A ATPases resembling protist plasma membrane H+-ATPases and a C-terminal regulatory domain is missing. The complete inventory of P-type ATPases in the major branches of Viridiplantae is an important starting point for elucidating the evolution in plants of these important pumps.

  8. In-Vitro Whole-Seedling Assay For Evaluating Non-Host Crop Plant ...

    African Journals Online (AJOL)

    In-Vitro Whole-Seedling Assay For Evaluating Non-Host Crop Plant Induction Of Germination Of Witch Weed Seeds. ... African Crop Science Journal ... A simple and inexpensive technique, In-vitro whole-seedling assay; was developed and tested for screening non-host crops for ability to stimulate germination of S.

  9. Chromosomal evolution in the plant family Solanaceae.

    Science.gov (United States)

    Wu, Feinan; Tanksley, Steven D

    2010-03-17

    Over the past decades, extensive comparative mapping research has been performed in the plant family Solanaceae. The recent identification of a large set of single-copy conserved orthologous (COSII) markers has greatly accelerated comparative mapping studies among major solanaceous species including tomato, potato, eggplant, pepper and diploid Nicotiana species (as well as tetraploid tobacco). The large amount of comparative data now available for these species provides the opportunity to describe the overall patterns of chromosomal evolution in this important plant family. The results of this investigation are described herein. We combined data from multiple COSII studies, and other comparative mapping studies performed in tomato, potato, eggplant, pepper and diploid Nicotiana species, to deduce the features and outcomes of chromosomal evolution in the Solanaceae over the past 30 million years. This includes estimating the rates and timing of chromosomal changes (inversions and translocations) as well as deducing the age of ancestral progenitor species and predicting their genome configurations. The Solanaceae has experienced chromosomal changes at a modest rate compared with other families and the rates are likely conserved across different lineages of the family. Chromosomal inversions occur at a consistently higher rate than do translocations. Further, we find evidences for non-random positioning of the chromosomal rearrangement breakpoints. This finding is consistent with the similar finding in mammals, where hot spots for chromosomal breakages have apparently played a significant role in shaping genome evolution. Finally, by utilizing multiple genome comparisons we were able to reconstruct the most likely genome configuration for a number of now-extinct progenitor species that gave rise to the extant solanaceous species used in this research. The results from this study provide the first broad overview of chromosomal evolution in the family Solanaceae, and

  10. Evolution of the Crop Rhizosphere: Impact of Domestication on Root Exudates in Tetraploid Wheat (Triticum turgidumL.).

    Science.gov (United States)

    Iannucci, Anna; Fragasso, Mariagiovanna; Beleggia, Romina; Nigro, Franca; Papa, Roberto

    2017-01-01

    Domestication has induced major genetic changes in crop plants to satisfy human needs and as a consequence of adaptation to agroecosystems. This adaptation might have affected root exudate composition, which can influence the interactions in the rhizosphere. Here, using two different soil types (sand, soil), we provide an original example of the impact of domestication and crop evolution on root exudate composition through metabolite profiling of root exudates for a panel of 10 wheat genotypes that correspond to the key steps in domestication of tetraploid wheat (wild emmer, emmer, durum wheat). Our data show that soil type can dramatically affect the composition of root exudates in the rhizosphere. Moreover, the composition of the rhizosphere metabolites is associated with differences among the genotypes of the wheat domestication groups, as seen by the high heritability of some of the metabolites. Overall, we show that domestication and breeding have had major effects on root exudates in the rhizosphere, which suggests the adaptive nature of these changes.

  11. Microorganism and Fungi Drive Evolution of Plant Synapses

    Directory of Open Access Journals (Sweden)

    Frantisek eBaluska

    2013-08-01

    Full Text Available In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and symbiotic microorganisms. These microorganisms are the driving force behind the evolution of plant synapses and other neuronal aspects of higher plants; this is especially pronounced in the root apices. Plant synapses allow synaptic cell-cell communication and coordination in plants, as well as sensory-motor integration in root apices searching for water and mineral nutrition. These neuronal aspects of higher plants are closely linked with their unique ability to adapt to environmental changes.

  12. Microorganism and filamentous fungi drive evolution of plant synapses.

    Science.gov (United States)

    Baluška, František; Mancuso, Stefano

    2013-01-01

    In the course of plant evolution, there is an obvious trend toward an increased complexity of plant bodies, as well as an increased sophistication of plant behavior and communication. Phenotypic plasticity of plants is based on the polar auxin transport machinery that is directly linked with plant sensory systems impinging on plant behavior and adaptive responses. Similar to the emergence and evolution of eukaryotic cells, evolution of land plants was also shaped and driven by infective and symbiotic microorganisms. These microorganisms are the driving force behind the evolution of plant synapses and other neuronal aspects of higher plants; this is especially pronounced in the root apices. Plant synapses allow synaptic cell-cell communication and coordination in plants, as well as sensory-motor integration in root apices searching for water and mineral nutrition. These neuronal aspects of higher plants are closely linked with their unique ability to adapt to environmental changes.

  13. Energy crops for biogas plants. Bavaria; Energiepflanzen fuer Biogasanlagen. Bayern

    Energy Technology Data Exchange (ETDEWEB)

    Aigner, A.; Biertuempel, A.; Conrad, M. (and others)

    2012-08-15

    For agriculturists in Bavaria (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  14. Salicornia as a crop plant in temperate regions: selection of genetically characterized ecotypes and optimization of their cultivation conditions

    National Research Council Canada - National Science Library

    Singh, Devesh; Buhmann, Anne K; Flowers, Tim J; Seal, Charlotte E; Papenbrock, Jutta

    2014-01-01

    .... Therefore, it is important to find alternatives to grow food crops and vegetables. Halophytes are naturally evolved salt-tolerant plants that are adapted to grow in environments that inhibit the growth of most glycophytic crop plants substantially...

  15. Managing Phenol Contents in Crop Plants by Phytochemical Farming and Breeding?Visions and Constraints

    OpenAIRE

    Dieter Treutter

    2010-01-01

    Two main fields of interest form the background of actual demand for optimized levels of phenolic compounds in crop plants. These are human health and plant resistance to pathogens and to biotic and abiotic stress factors. A survey of agricultural technologies influencing the biosynthesis and accumulation of phenolic compounds in crop plants is presented, including observations on the effects of light, temperature, mineral nutrition, water management, grafting, elevated atmospheric CO2, growt...

  16. Flower Constancy, Insect Psychology, and Plant Evolution

    Science.gov (United States)

    Chittka, Lars; Thomson, James D.; Waser, Nickolas M.

    Individuals of some species of pollinating insects tend to restrict their visits to only a few of the available plant species, in the process bypassing valuable food sources. The question of why this flower constancy exists is a rich and important one with implications for the organization of natural communities of plants, floral evolution, and our understanding of the learning processes involved in finding food. Some scientists have assumed that flower constancy is adaptive per se. Others argued that constancy occurs because memory capacity for floral features in insects is limited, but attempts to identify the limitations often remained rather simplistic. We elucidate now different sensory and motor memories from natural foraging tasks are stored and retrieved, using concepts from modern learning science and visual search, and conclude that flower constancy is likely to have multiple causes. Possible constraints favoring constancy are interference sensitivity of short-term memory, and temporal limitations on retrieving information from long-term memory as rapidly as from short-term memory, but further empirical evidence is needed to substantiate these possibilities. In addition, retrieving memories may be slower and more prone to errors when there are several options than when an insect copes with only a single task. In addition to memory limitations, we also point out alternative explanations for flower constancy. We then consider the way in which floral parameters, such as interplant distances, nectar rewards, flower morphology, and floral color (as seen through bees' eyes) affect constancy. Finally, we discuss the implications of pollinator constancy for plant evolution. To date there is no evidence that flowers have diverged to favor constancy, although the appropriate tests may not have yet been conducted. However, there is good evidence against the notion that pollinator constancy is involved in speciation or maintenance of plant species integrity.

  17. Molecular Genetic Approaches for Environmental Stress Tolerant Crop Plants: Progress and Prospects.

    Science.gov (United States)

    Kaur, Ranjeet; Kumar Bhunia, Rupam; Ghosh, Ananta Kumar

    2016-01-01

    Global food security is threatened by the severe environmental conditions that have reduced the worldwide crop yield. Plants possess inherent mechanisms to cope with the initial stress phase but to ensure their survival through harsh climate, the intervention of genetic engineering is desirable. We present a comprehensive review on the progress made in the field of developing environmental stress tolerant crops and the prospects that can be undertaken for achieving it. We review the effects of abiotic and biotic stresses on crop plants, and the use of different molecular genetic approaches to cope with these environmental stresses for establishment of sustainable agriculture. The various strategies employed in different crops have also been discussed. We also summarized the major patents in the field of plant stress tolerance that have been granted in the last five years. On the basis of these analyses, we propose that genetic engineering of crops is the preferred approach over the traditional methods for yielding healthier and viable agriculture in response to the different stressful environments. The wild progenitors of cultivated crop species can prove to be highly potential genetic resources in this regard and can be exploited to produce better crops that are relatively tolerant towards various environmental stresses. Thus, elucidation of genetic loci and deciphering the underlying mechanisms that confer tolerance to plants against stressful conditions followed by its successful introgression into elite, high-yielding crop varieties can be an effective way to engineer the crops for sustainable agriculture.

  18. Diverse influence of nanoparticles on plant growth with a particular emphasis on crop plants

    Directory of Open Access Journals (Sweden)

    Anna Milewska-Hendel

    2016-12-01

    Full Text Available The article describes the current knowledge about the impact of nanoparticles on plant development with a particular emphasis on crop plants. Nanotechnology is an intensively developing field of science. This is due to the enormous hopes that have been placed on the achievements of nanotechnology in various areas of life. Increasingly, it has been noted that apart from the future benefits of nanotechnology in our everyday life, nanoparticles (NPs may also have adverse effects that have not been sufficiently explored and understood. Most analyses to date have been focused on the influence of nanomaterials on the physiological processes primarily in animals, humans and bacteria. Although our knowledge about the influence of NPs on the development of plants is considerably smaller, the current views are presented below. Such knowledge is extremely important since NPs can enter the food chain, which may have an influence on human health.

  19. Energy crops for biogas plants. Brandenburg; Energiepflanzen fuer Biogasanlagen. Brandenburg

    Energy Technology Data Exchange (ETDEWEB)

    Adam, L.; Barthelmes, G.; Biertuempfel, A. (and others)

    2012-06-15

    In the brochure under consideration, the Agency for Renewable Resources (Guelzen-Pruezen, Federal Republic of Germany) reported on recommendations on alternative cropping systems for energy crop rotations in order to achieve high yields in combination with high diversity, risk spreading and sustainability. In particular, the natural site conditions in the Federal State of Brandenburg (Federal Republic of Germany) are determined.

  20. Forage radish winter cover crop suppresses winter annual weeds in fall and before corn planting

    Science.gov (United States)

    Forage radish (Raphanus sativus L. var. longipinnatus) is a new winter cover crop in the Mid-Atlantic region. The objective of this project was to characterize the repeatability, amount, and duration of weed suppression during and after a fall-planted forage radish cover crop and to quantify the sub...

  1. Fusarium oxysporum f.sp. cepae dynamics: in-plant multiplication and crop sequence simulations

    NARCIS (Netherlands)

    Leoni, C.; Vries, de M.; Braak, ter C.J.F.; Bruggen, van A.H.C.; Rossing, W.A.H.

    2013-01-01

    To reduce Fusarium Basal Rot caused by Fusarium oxysporum f.sp. cepae (Foc) through crop rotation, plant species should be selected based on Foc multiplication in their roots. Foc multiplication rates in 13 plant species were tested in a greenhouse. All plant species enabled Foc multiplication. The

  2. Novel enabling technologies of gene isolation and plant transformation for improved crop protection

    Energy Technology Data Exchange (ETDEWEB)

    Torok, Tamas

    2013-02-04

    Meeting the needs of agricultural producers requires the continued development of improved transgenic crop protection products. The completed project focused on developing novel enabling technologies of gene discovery and plant transformation to facilitate the generation of such products.

  3. The Nutritional Value of Selected Moist-soil Plants and Agricultural crops for Canada Geese

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Migrant and wintering waterfowl commonly utilize both agricultural crops and native plants as food. Producing these foods and making them available for consumption...

  4. Molecular genetic approaches for environmental stress tolerant crop plants: Progress and prospects.

    Science.gov (United States)

    Kaur, Ranjeet; Ghosh, Ananta Kumar; Bhunia, Rupam Kumar

    2016-08-05

    Global food security is threatened by the severe environmental conditions that have reduced the worldwide crop yield. Plants possess inherent mechanisms to cope with the initial stress phase but to ensure their survival through harsh climate, the intervention of genetic engineering is desirable. Elucidation of genetic loci and deciphering the underlying mechanisms that confer tolerance to plants against stressful conditions followed by its successful introgression into elite, high-yielding crop varieties can be an effective way to engineer the crops for increasing productivity. This review provides an overview about the effects of abiotic and biotic stresses on crop plants and the use of genetic engineering approach to cope with these environmental stresses for a sustainable agriculture. Major patents in the field of plant stress tolerance in the last five years have also been summarized.

  5. Energy crops for biogas plants. Lower Saxony; Energiepflanzen fuer Biogasanlagen. Niedersachsen

    Energy Technology Data Exchange (ETDEWEB)

    Aurbacher, J.; Benke, M.; Formowitz, B. (and others)

    2012-06-15

    In the brochure under consideration the Agency for Renewable Resources (Guelzow-Pruezen, Federal Republic of Germany) reports on the support of the implementation of different plant cultures in structure of plantations and crop rotation systems of companies under consideration of the Federal State Lower Saxony. The main chapters of this brochure are: Crops for the production of biogas; implementation in plantations; ensilage and biogas yields; economy of the cultivation of energy plants.

  6. Insect oviposition behavior affects the evolution of adaptation to Bt crops: consequences for refuge policies

    NARCIS (Netherlands)

    Jongsma, M.A.; Gould, F.; Legros, M.; Yang, L.; Loon, van J.J.A.; Dicke, M.

    2010-01-01

    The major lepidopteran insect pests of cotton and maize harbor intra-specific variation for behavior determining the selection of host plants for oviposition. Yet, the consequences of behavioral adaptation for fitness have neither been modeled nor monitored for Bt cotton and maize crops, the most

  7. Plant retroviruses: structure, evolution and future applications | Zaki ...

    African Journals Online (AJOL)

    Until recently, retroviruses were thought to be restricted to vertebrates. Plant sequencing projects revealed that plant genomes contain retroviral-like sequences. This review aims to address the structure and evolution of plant retroviruses. In addition, it proposes future applications for these important key components of plant ...

  8. Evolution Analysis of Simple Sequence Repeats in Plant Genome.

    Science.gov (United States)

    Qin, Zhen; Wang, Yanping; Wang, Qingmei; Li, Aixian; Hou, Fuyun; Zhang, Liming

    2015-01-01

    Simple sequence repeats (SSRs) are widespread units on genome sequences, and play many important roles in plants. In order to reveal the evolution of plant genomes, we investigated the evolutionary regularities of SSRs during the evolution of plant species and the plant kingdom by analysis of twelve sequenced plant genome sequences. First, in the twelve studied plant genomes, the main SSRs were those which contain repeats of 1-3 nucleotides combination. Second, in mononucleotide SSRs, the A/T percentage gradually increased along with the evolution of plants (except for P. patens). With the increase of SSRs repeat number the percentage of A/T in C. reinhardtii had no significant change, while the percentage of A/T in terrestrial plants species gradually declined. Third, in dinucleotide SSRs, the percentage of AT/TA increased along with the evolution of plant kingdom and the repeat number increased in terrestrial plants species. This trend was more obvious in dicotyledon than monocotyledon. The percentage of CG/GC showed the opposite pattern to the AT/TA. Forth, in trinucleotide SSRs, the percentages of combinations including two or three A/T were in a rising trend along with the evolution of plant kingdom; meanwhile with the increase of SSRs repeat number in plants species, different species chose different combinations as dominant SSRs. SSRs in C. reinhardtii, P. patens, Z. mays and A. thaliana showed their specific patterns related to evolutionary position or specific changes of genome sequences. The results showed that, SSRs not only had the general pattern in the evolution of plant kingdom, but also were associated with the evolution of the specific genome sequence. The study of the evolutionary regularities of SSRs provided new insights for the analysis of the plant genome evolution.

  9. Land plants, weathering, and Paleozoic climatic evolution

    Science.gov (United States)

    Goddéris, Yves; Maffre, Pierre; Donnadieu, Yannick; Carretier, Sébastien

    2017-04-01

    At the end of the Paleozoic, the Earth plunged into the longest and most severe glaciation of the Phanerozoic eon (Montanez et al., 2013). The triggers for this event (called the Late Paleozoic Ice Age, LPIA) are still debated. Based on field observations and laboratory experiments showing that CO2 consumption by rock weathering is enhanced by the presence of plants, the onset of the LPIA has been related to the colonization of the continents by vascular plants in the latest Devonian. By releasing organic acids, concentrating respired CO2 in the soil, and by mechanically breaking rocks with their roots, land plants may have increased the weatherability of the continental surfaces. The "greening" of the continents may also have contributed to an enhanced burial of organic carbon in continental sedimentary basins, assuming that lignin decomposers have not yet evolved (Berner, 2004). As a consequence, CO2 went down, setting the conditions for the onset of the LPIA. This scenario is now widely accepted in the scientific community, and reinforces the feeling that biotic evolutionary steps are main drivers of the long-term climatic evolution. Although appealing, this scenario suffers from some weaknesses. The timing of the continent colonization by vascular plants was achieved in the late Devonian, several tens of million years before the onset of the LPIA (Davies and Gibling, 2013). Second, lignin decomposer fungi were present at the beginning of the Carboniferous, 360 million years ago while the LPIA started around 340-330 Ma (Nelsen et al., 2016). Land plants have also decreased the continental albedo, warming the Earth surface and promoting runoff. Weathering was thus facilitated and CO2 went down. Yet, temperature may have stayed constant, the albedo change compensating for the CO2 fall (Le Hir et al., 2010). From a modelling point of view, the effect of land plants on CO2 consumption by rock weathering is accounted for by forcing the weatherability of the

  10. New method to determine crop planting date in the ACME Land Model

    Science.gov (United States)

    Drewniak, B.

    2016-12-01

    Crops in the ACME Land Model (ALM) are currently restricted to temperate latitudes because the day of planting is determined by a temperature threshold that is not appropriate for use in tropical zones. Tropical regions typically have temperature ranges that can support crop production year-round; however, the growing season in many areas of the tropics and sub-tropics is limited by water availability. In these regions, precipitation should be considered when establishing planting date. Therefore, a new scheme that takes into account temperature and precipitation seasonality is applied to determine plant date. The type of seasonality of a region is determined by coefficients of variation of temperature and precipitation. Plant date in areas with temperature seasonality is determined by soil temperature thresholds. In areas with precipitation seasonality, planting occurs at the beginning of the main wet season, which is determined by the ratio of precipitation to potential evapotranspiration, calculated with the Penman-Monteith method. The new plant date methodology in ALM functions globally, allows the plant date to evolve with changes in local climate, and easily accommodates changes in land use because potential plant dates are calculated in grid cells where crops are currently not grown, thereby requiring no external inputs. Global estimates of plant dates are generally consistent with observations. The new plant date scheme will be presented, including results on the variability of planting day of year and how plant dates may change under future climate scenarios.

  11. New thrips-transmitted plant viruses in Florida crops

    Science.gov (United States)

    The thrips-transmitted tospoviruses Tomato spotted wilt virus, Groundnut ringspot virus and Tomato chlorotic spot virus are present in south Florida. All three species cause economically significant disease in vegetable and ornamental crops, and may also be problematic in peanut. Control of both t...

  12. Public Acceptance of Plant Biotechnology and GM Crops.

    Science.gov (United States)

    Lucht, Jan M

    2015-07-30

    A wide gap exists between the rapid acceptance of genetically modified (GM) crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths-also affecting the development of virus resistant transgenic crops-of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer's attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion-including calls for labeling of GM food-in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers' concerns with transgenic crops, but it is not clear yet how consumers' attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values.

  13. Utilization of urea, ammonia, nitrite, and nitrate by crop plants in a Controlled Ecological Life Support System (CELSS)

    Science.gov (United States)

    Huffaker, R. C.; Rains, D. W.; Qualset, C. O.

    1982-01-01

    The utilization of nitrogen compounds by crop plants is studied. The selection of crop varieties for efficient production using urea, ammonia, nitrite, and nitrate, and the assimilation of mixed nitrogen sources by cereal leaves and roots are discussed.

  14. Plant structure in crop production: considerations on application of FSPM

    NARCIS (Netherlands)

    Vos, J.; Evers, J.B.

    2013-01-01

    Cereals, potato and glasshouse cut rose, representing monocot annuals, vegetative propagated dicot annual and woody perennials, have different structural development. ‘Bud break’, initiating tillering (monocots) and branching (dicots) is a key process determining plant structure. Plant population

  15. Managing Phenol Contents in Crop Plants by Phytochemical Farming and Breeding—Visions and Constraints

    Directory of Open Access Journals (Sweden)

    Dieter Treutter

    2010-03-01

    Full Text Available Two main fields of interest form the background of actual demand for optimized levels of phenolic compounds in crop plants. These are human health and plant resistance to pathogens and to biotic and abiotic stress factors. A survey of agricultural technologies influencing the biosynthesis and accumulation of phenolic compounds in crop plants is presented, including observations on the effects of light, temperature, mineral nutrition, water management, grafting, elevated atmospheric CO2, growth and differentiation of the plant and application of elicitors, stimulating agents and plant activators. The underlying mechanisms are discussed with respect to carbohydrate availability, trade-offs to competing demands as well as to regulatory elements. Outlines are given for genetic engineering and plant breeding. Constraints and possible physiological feedbacks are considered for successful and sustainable application of agricultural techniques with respect to management of plant phenol profiles and concentrations.

  16. Managing phenol contents in crop plants by phytochemical farming and breeding-visions and constraints.

    Science.gov (United States)

    Treutter, Dieter

    2010-03-02

    Two main fields of interest form the background of actual demand for optimized levels of phenolic compounds in crop plants. These are human health and plant resistance to pathogens and to biotic and abiotic stress factors. A survey of agricultural technologies influencing the biosynthesis and accumulation of phenolic compounds in crop plants is presented, including observations on the effects of light, temperature, mineral nutrition, water management, grafting, elevated atmospheric CO(2), growth and differentiation of the plant and application of elicitors, stimulating agents and plant activators. The underlying mechanisms are discussed with respect to carbohydrate availability, trade-offs to competing demands as well as to regulatory elements. Outlines are given for genetic engineering and plant breeding. Constraints and possible physiological feedbacks are considered for successful and sustainable application of agricultural techniques with respect to management of plant phenol profiles and concentrations.

  17. Tissue culture as a plant production technique for horticultural crops ...

    African Journals Online (AJOL)

    Over 100 years ago, Haberlandt envisioned the concept of plant tissue culture and provided the groundwork for the cultivation of plant cells, tissues and organs in culture. Initially plant tissue cultures arose as a research tool and focused on attempts to culture and study the development of small, isolated cells and segments ...

  18. zone of nigeria as affected by planting pattern, crop

    African Journals Online (AJOL)

    grain yield, threshing percentage, harvest index, gross monetary returns significantly under all planting patterns .... dàys after planting (DAP) to when at least 50% of the plants in the plot had ... and ripening of cowpea compared to the no-spray.

  19. Recruitment and attrition of associated plants under a shading crop canopy: Model selection and calibration

    NARCIS (Netherlands)

    Stilma, E.S.C.; Keesman, K.J.; Werf, van der W.

    2009-01-01

    Associated plant and animal diversity provides ecosystem services within crop production systems. The importance of the maintenance or restoration of diversity is therefore increasingly acknowledged. Here we study the population dynamics of associated annual plants (`weeds¿) during the growth of a

  20. Leaf epidermal changes in three common crop plants found in a gas ...

    African Journals Online (AJOL)

    The study investigated the impact of gas flaring on soil and air quality, as well as quantitative and qualitative anatomical characters of three selected plants Musa paradisiaca, Carica papaya and Talinum triangulare in and around Oben Flow Station. Most of these test crop plants located around the gas flare site showed ...

  1. Impact of crop residues on seed germination of native desert plants ...

    African Journals Online (AJOL)

    Allelopathy refers to an ecological phenomenon where there is plant-plant interference through release of organic chemicals (allelochemicals) in the surrounding soil environment as water leachates or root exudates. Crop residues produce allelochemicals that may inhibit seed germination of many weeds. In this study, I ...

  2. Reproduction - a factor of plant evolution

    Directory of Open Access Journals (Sweden)

    Ion I. Bǎra

    2014-01-01

    Full Text Available The process of reproduction (amphimixis and apomixis represents a major factor of evolution. The facultative apomictic species are the pioneers of evolution. They combine the adventages of amphimixis (high degree of variability and heterogenesis and apomixis (relative stability and low material expenditure assuring a rapid rate of adaptive evolution.

  3. Public Acceptance of Plant Biotechnology and GM Crops

    Directory of Open Access Journals (Sweden)

    Jan M. Lucht

    2015-07-01

    Full Text Available A wide gap exists between the rapid acceptance of genetically modified (GM crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths—also affecting the development of virus resistant transgenic crops—of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer’s attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion—including calls for labeling of GM food—in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers’ concerns with transgenic crops, but it is not clear yet how consumers’ attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values.

  4. Insect-plant interactions in a crop protection perspective

    OpenAIRE

    Kaiser, L; Ode, P.; van Nouhuys, S.; Calatayud, Paul-André; Colazza, S.; Cortesero, A.M.; Thiel, A.; J. Van der Baaren

    2017-01-01

    Populations of herbivorous insects are naturally consumed by other predacious or predatory insect species. These entomophagous insects are thus plant-dwelling organisms that use the plant for several vital functions and are affected by plant traits at the evolutionary, organism and population levels. Many entomophagous species are used for the biological control of insect pests worldwide. The aim of this chapter is to provide an exhaustive review of mechanisms underlying the interactions betw...

  5. Single-tube hydroponics as a novel idea for small-scale production of crop seed in a plant incubator.

    Science.gov (United States)

    Kuroda, Masaharu; Ikenaga, Sachiko

    2015-01-01

    We present a novel protocol for small-scale production of crop seed in a plant incubator termed "Single-tube hydroponics." Our protocol minimizes the materials and methods for cultivation whereby a large number of independent plants can be cultured in a limited space. This study may aid in the improvement of crop seed components, especially in the cultivation of transgenic plants.

  6. Cover Image Identification of Plant Species for Crop Pollinator Habitat Enhancement in the Northern Prairies

    OpenAIRE

    Diana Bizecki Robson

    2014-01-01

    Wild pollinators have a positive impact on the productivity of insect-pollinated crops. Consequently, landowners are being encouraged to maintain and grow wildflower patches to provide habitat for important pollinators. Research on plant-pollinator interaction matrices indicates that a small number of “core” plants provide a disproportionately high amount of pollen and nectar to insects. This matrix data can be used to help design wildflower plantings that provide optimal resources for desira...

  7. Plant prebiotics and human health: Biotechnology to breed prebiotic-rich nutritious food crops

    Directory of Open Access Journals (Sweden)

    Sangam Dwivedi

    2014-09-01

    Full Text Available Microbiota in the gut play essential roles in human health. Prebiotics are non-digestible complex carbohydrates that are fermented in the colon, yielding energy and short chain fatty acids, and selectively promote the growth of Bifidobacteria and Lactobacillae in the gastro-intestinal tract. Fructans and inulin are the best-characterized plant prebiotics. Many vegetable, root and tuber crops as well as some fruit crops are the best-known sources of prebiotic carbohydrates, while the prebiotic-rich grain crops include barley, chickpea, lentil, lupin, and wheat. Some prebiotic-rich crop germplasm have been reported in barley, chickpea, lentil, wheat, yacon, and Jerusalem artichoke. A few major quantitative trait loci and gene-based markers associated with high fructan are known in wheat. More targeted search in genebanks using reduced subsets (representing diversity in germplasm is needed to identify accessions with prebiotic carbohydrates. Transgenic maize, potato and sugarcane with high fructan, with no adverse effects on plant development, have been bred, which suggests that it is feasible to introduce fructan biosynthesis pathways in crops to produce health-imparting prebiotics. Developing prebiotic-rich and super nutritious crops will alleviate the widespread malnutrition and promote human health. A paradigm shift in breeding program is needed to achieve this goal and to ensure that newly-bred crop cultivars are nutritious, safe and health promoting.

  8. Plant Residual Management in different Crop Rotations System on Potato Tuber Yield Loss Affected by Wireworms

    Directory of Open Access Journals (Sweden)

    A. Zarea Feizabadi

    2016-07-01

    Full Text Available Introduction: Selection a proper crop rotation based on environmental conservation rules is a key factor for increasing long term productivity. On the other hand, the major problem in reaching agricultural sustainability is lack of soil organic matter. Recently, a new viewpoint has emerged based on efficient use of inputs, environmental protection, ecological economy, food supply and security. Crop rotation cannot supply and restore plant needed nutrients, so gradually the productivity of rotation system tends to be decreased. Returning the plant residues to the soil helps to increase its organic matter and fertility in long-term period. Wireworms are multi host pests and we can see them in wheat and barley too. The logic way for their control is agronomic practices like as crop rotation. Wireworms’ population and damages are increased with using grasses and small seed gramineas in mild winters, variation in cropping pattern, reduced chemical control, and cover crops in winter. In return soil cultivation, crop rotation, planting date, fertilizing, irrigation and field health are the examples for the effective factors in reducing wireworms’ damage. Materials and Methods: In order to study the effect of crop rotations, residue management and yield damage because of wireworms’ population in soil, this experiment was conducted using four rotation systems for five years in Jolgeh- Rokh agricultural research station. Crop rotations were included, 1 Wheat monoculture for the whole period (WWWWW, 2 Wheat- wheat- wheat- canola- wheat (WWWCW, 3 Wheat- sugar beet- wheat- potato- wheat (WSWPW, 4 Wheat- maize- wheat- potato- wheat (WMWPW as main plots and three levels of returning crop residues to soil (returning 0, 50 and 100% produced crop residues to soil were allocated as sub plots. This experiment was designed as split plot based on RCBD design with three replications. After ending each rotation treatment, the field was sowed with potato cv. Agria

  9. Grass plants crop water consumption model in urban parks located ...

    African Journals Online (AJOL)

    The most important issue is the to use of urban space to increase the number and size of green areas. As well as another important issue is to work towards maintaining these spaces. One such important effort is to meet the water needs of plants. Naturally, the amount of water needed by plants depends on the species.

  10. Food and feed safety aspects of cisgenic crop plant varieties

    NARCIS (Netherlands)

    Prins, T.W.; Kok, E.J.

    2010-01-01

    This report presents the results of the discussions that identified food and feed safety aspects of cisgenic plant varieties in comparison to conventional varieties on the one hand and transgenic plant varieties on the other hand. It was concluded that on the basis of the general characteristics of

  11. Editorial: Plant organ abscission: from models to crops

    Science.gov (United States)

    The shedding of plant organs is a highly coordinated process essential for both vegetative and reproductive development (Addicott, 1982; Sexton and Roberts, 1982; Roberts et al., 2002; Leslie et al., 2007; Roberts and Gonzalez-Carranza, 2007; Estornell et al., 2013). Research with model plants, name...

  12. Crops in silico: A community wide multi-scale computational modeling framework of plant canopies

    Science.gov (United States)

    Srinivasan, V.; Christensen, A.; Borkiewic, K.; Yiwen, X.; Ellis, A.; Panneerselvam, B.; Kannan, K.; Shrivastava, S.; Cox, D.; Hart, J.; Marshall-Colon, A.; Long, S.

    2016-12-01

    Current crop models predict a looming gap between supply and demand for primary foodstuffs over the next 100 years. While significant yield increases were achieved in major food crops during the early years of the green revolution, the current rates of yield increases are insufficient to meet future projected food demand. Furthermore, with projected reduction in arable land, decrease in water availability, and increasing impacts of climate change on future food production, innovative technologies are required to sustainably improve crop yield. To meet these challenges, we are developing Crops in silico (Cis), a biologically informed, multi-scale, computational modeling framework that can facilitate whole plant simulations of crop systems. The Cis framework is capable of linking models of gene networks, protein synthesis, metabolic pathways, physiology, growth, and development in order to investigate crop response to different climate scenarios and resource constraints. This modeling framework will provide the mechanistic details to generate testable hypotheses toward accelerating directed breeding and engineering efforts to increase future food security. A primary objective for building such a framework is to create synergy among an inter-connected community of biologists and modelers to create a realistic virtual plant. This framework advantageously casts the detailed mechanistic understanding of individual plant processes across various scales in a common scalable framework that makes use of current advances in high performance and parallel computing. We are currently designing a user friendly interface that will make this tool equally accessible to biologists and computer scientists. Critically, this framework will provide the community with much needed tools for guiding future crop breeding and engineering, understanding the emergent implications of discoveries at the molecular level for whole plant behavior, and improved prediction of plant and ecosystem

  13. Impact of genetically modified crops and their management on soil microbially mediated plant nutrient transformations.

    Science.gov (United States)

    Motavalli, P P; Kremer, R J; Fang, M; Means, N E

    2004-01-01

    One of the potential environmental effects of the recent rapid increase in the global agricultural area cultivated with transgenic crops is a change in soil microbially mediated processes and functions. Among the many essential functions of soil biota are soil organic matter decomposition, nutrient mineralization and immobilization, oxidation-reduction reactions, biological N fixation, and solubilization. However, relatively little research has examined the direct and indirect effects of transgenic crops and their management on microbially mediated nutrient transformations in soils. The objectives of this paper are to review the available literature related to the environmental effects of transgenic crops and their management on soil microbially mediated nutrient transformations, and to consider soil properties and climatic factors that may affect the impact of transgenic crops on these processes. Targeted genetic traits for improved plant nutrition include greater plant tolerance to low Fe availability in alkaline soils, enhanced acquisition of soil inorganic and organic P, and increased assimilation of soil N. Among the potential direct effects of transgenic crops and their management are changes in soil microbial activity due to differences in the amount and composition of root exudates, changes in microbial functions resulting from gene transfer from the transgenic crop, and alteration in microbial populations because of the effects of management practices for transgenic crops, such as pesticide applications, tillage, and application of inorganic and organic fertilizer sources. Possible indirect effects of transgenic crops, including changes in the fate of transgenic crop residues and alterations in land use and rates of soil erosion, deserve further study. Despite widespread public concern, no conclusive evidence has yet been presented that currently released transgenic crops, including both herbicide and pest resistant crops, are causing significant direct

  14. Selection during crop diversification involves correlated evolution of the circadian clock and ecophysiological traits in Brassica rapa.

    Science.gov (United States)

    Yarkhunova, Yulia; Edwards, Christine E; Ewers, Brent E; Baker, Robert L; Aston, Timothy Llewellyn; McClung, C Robertson; Lou, Ping; Weinig, Cynthia

    2016-04-01

    Crop selection often leads to dramatic morphological diversification, in which allocation to the harvestable component increases. Shifts in allocation are predicted to impact (as well as rely on) physiological traits; yet, little is known about the evolution of gas exchange and related anatomical features during crop diversification. In Brassica rapa, we tested for physiological differentiation among three crop morphotypes (leaf, turnip, and oilseed) and for correlated evolution of circadian, gas exchange, and phenological traits. We also examined internal and surficial leaf anatomical features and biochemical limits to photosynthesis. Crop types differed in gas exchange; oilseed varieties had higher net carbon assimilation and stomatal conductance relative to vegetable types. Phylogenetically independent contrasts indicated correlated evolution between circadian traits and both gas exchange and biomass accumulation; shifts to shorter circadian period (closer to 24 h) between phylogenetic nodes are associated with higher stomatal conductance, lower photosynthetic rate (when CO2 supply is factored out), and lower biomass accumulation. Crop type differences in gas exchange are also associated with stomatal density, epidermal thickness, numbers of palisade layers, and biochemical limits to photosynthesis. Brassica crop diversification involves correlated evolution of circadian and physiological traits, which is potentially relevant to understanding mechanistic targets for crop improvement. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  15. Photoreceptor Mediated Plant Growth Responses: Implications for Photoreceptor Engineering toward Improved Performance in Crops

    Directory of Open Access Journals (Sweden)

    Ophilia I. L. Mawphlang

    2017-07-01

    Full Text Available Rising temperatures during growing seasons coupled with altered precipitation rates presents a challenging task of improving crop productivity for overcoming such altered weather patterns and cater to a growing population. Light is a critical environmental factor that exerts a powerful influence on plant growth and development ranging from seed germination to flowering and fruiting. Higher plants utilize a suite of complex photoreceptor proteins to perceive surrounding red/far-red (phytochromes, blue/UV-A (cryptochromes, phototropins, ZTL/FKF1/LKP2, and UV-B light (UVR8. While genomic studies have also shown that light induces extensive reprogramming of gene expression patterns in plants, molecular genetic studies have shown that manipulation of one or more photoreceptors can result in modification of agronomically beneficial traits. Such information can assist researchers to engineer photoreceptors via genome editing technologies to alter expression or even sensitivity thresholds of native photoreceptors for targeting aspects of plant growth that can confer superior agronomic value to the engineered crops. Here we summarize the agronomically important plant growth processes influenced by photoreceptors in crop species, alongwith the functional interactions between different photoreceptors and phytohormones in regulating these responses. We also discuss the potential utility of synthetic biology approaches in photobiology for improving agronomically beneficial traits of crop plants by engineering designer photoreceptors.

  16. Phytohormones and their metabolic engineering for abiotic stress tolerance in crop plants

    Directory of Open Access Journals (Sweden)

    Shabir H. Wani

    2016-06-01

    Full Text Available Abiotic stresses including drought, salinity, heat, cold, flooding, and ultraviolet radiation causes crop losses worldwide. In recent times, preventing these crop losses and producing more food and feed to meet the demands of ever-increasing human populations have gained unprecedented importance. However, the proportion of agricultural lands facing multiple abiotic stresses is expected only to rise under a changing global climate fueled by anthropogenic activities. Identifying the mechanisms developed and deployed by plants to counteract abiotic stresses and maintain their growth and survival under harsh conditions thus holds great significance. Recent investigations have shown that phytohormones, including the classical auxins, cytokinins, ethylene, and gibberellins, and newer members including brassinosteroids, jasmonates, and strigolactones may prove to be important metabolic engineering targets for producing abiotic stress-tolerant crop plants. In this review, we summarize and critically assess the roles that phytohormones play in plant growth and development and abiotic stress tolerance, besides their engineering for conferring abiotic stress tolerance in transgenic crops. We also describe recent successes in identifying the roles of phytohormones under stressful conditions. We conclude by describing the recent progress and future prospects including limitations and challenges of phytohormone engineering for inducing abiotic stress tolerance in crop plants.

  17. Evolution of the Crop Rhizosphere: Impact of Domestication on Root Exudates in Tetraploid Wheat (Triticum turgidum L.

    Directory of Open Access Journals (Sweden)

    Anna Iannucci

    2017-12-01

    Full Text Available Domestication has induced major genetic changes in crop plants to satisfy human needs and as a consequence of adaptation to agroecosystems. This adaptation might have affected root exudate composition, which can influence the interactions in the rhizosphere. Here, using two different soil types (sand, soil, we provide an original example of the impact of domestication and crop evolution on root exudate composition through metabolite profiling of root exudates for a panel of 10 wheat genotypes that correspond to the key steps in domestication of tetraploid wheat (wild emmer, emmer, durum wheat. Our data show that soil type can dramatically affect the composition of root exudates in the rhizosphere. Moreover, the composition of the rhizosphere metabolites is associated with differences among the genotypes of the wheat domestication groups, as seen by the high heritability of some of the metabolites. Overall, we show that domestication and breeding have had major effects on root exudates in the rhizosphere, which suggests the adaptive nature of these changes.

  18. On streamlining the Ukrainian names of plants. Information 5. Species names for pome fruit crops

    Directory of Open Access Journals (Sweden)

    В. М. Меженський

    2015-12-01

    Full Text Available To analyse the modern classification and nomenclature of species of pome fruit crops which varieties are listed in the State Register of Plants Varieties Suitable for Dissemination in Ukraine, and improve terminological system of the Ukrainian names of both species and garden crops. Results. Fruit cultivars and most apple clonal rootstocks belong to Malus pumila, and ornamental cultivars belong to Malus gloriosa. The most common scientific name of the cultivated apple, especially among horticulturists, is Malus domestica, although according to the principle of priority the name Malus pumila should have the advantage. As far as Nomenclature Committee for Vascular Plants has rejected the proposal to conserve the name Malus domestica, Malus pumila is correct name for the cultivated apple. The use of synonymic name Malus domestica should be avoided in both scientific and scientific-popular papers for stability of nomenclature. Pear cultivars listed in the State Register of Plants Varieties Suitable for Dissemination in Ukraine are presented by Pyrus communis, and pear rootstocks – by Cydonia oblonga. Fruit cultivars of the latter belong to separate fruit crop named quince. An apple-quince hybrid was registered as universal clonal rootstock for pome fruit crops. The State Register of Plants Varieties Suitable for Dissemination in Ukraine also contains nonconventional fruit crops such as Chaenomeles and hawthorn that consist of some species and nothospecies. Conclusions. In scientific publications one should stop the use of synonymic name Malus domestica in favour of the correct name for cultivated apple Malus pumila. Apple, pears and Chaenomeles cultivars listed in the State Register of Plants Varieties Suitable for Dissemination in Ukraine have a complex multispecies origin whereas quince, hawthorn and pear roostock cultivars systematically are monospecies. A universal roootstock of pome fruit crops is Cydolus, or apple-quince, that resulted

  19. Fertilizers and Mixed Crop Cultivation of Chromium Tolerant and Sensitive Plants under Chromium Toxicity

    Directory of Open Access Journals (Sweden)

    B. Dheeba

    2015-01-01

    Full Text Available Zea mays (maize and Vigna radiata (green gram are found to be the chromium (Cr tolerant and sensitive plants, respectively. In the present paper, we investigate the reduction of the toxicity of Cr in the sensitive plants by the mixed crop cultivation in the field using various amendments. Further, the potassium dichromate was used as the source of hexavalent Cr. The results indicated that Cr adversely affects both the growth and yield of plants. The soil properties vary with Cr and different fertilizer amendments and the yield of both plants were affected by Cr. We conclude that metal accumulation of seeds of green gram was higher than corn and the application of single fertilizer either farm yard manure (FYM or nitrogen, phosphorous, and potassium (NPK enhances the growth and yield of both the tolerant and sensitive plants in the mixed crop cultivations.

  20. Coping Mechanisms for Crop Plants in Drought-prone Environments

    National Research Council Canada - National Science Library

    PETER M. NEUMANN

    2008-01-01

    .... • Scope After a general introduction to the problems of water availability, this review focuses on a critical evaluation of recent progress in unravelling mechanisms for modifying plant growth responses to drought...

  1. Plant glutathione S-transferase classification, structure and evolution ...

    African Journals Online (AJOL)

    Glutathione S-transferases are multifunctional proteins involved in diverse intracellular events such as primary and secondary metabolisms, stress metabolism, herbicide detoxification and plant protection ... Key words: Glutathione S-transferases (GST), classification, structure, evolution, phylogenetic analysis, xenobiotics.

  2. Functional evolution in the plant SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL gene family

    Directory of Open Access Journals (Sweden)

    Jill Christine Preston

    2013-04-01

    Full Text Available The SQUAMOSA-PROMOTER BINDING PROTEIN-LIKE (SPL family of transcription factors is functionally diverse, controlling a number of fundamental aspects of plant growth and development, including vegetative phase change, flowering time, branching, and leaf initiation rate. In natural plant populations, variation in flowering time and shoot architecture have major consequences for fitness. Likewise, in crop species, variation in branching and developmental rate impact biomass and yield. Thus, studies aimed at dissecting how the various functions are partitioned among different SPL genes in diverse plant lineages are key to providing insight into the genetic basis of local adaptation and have already garnered attention by crop breeders. Here we use phylogenetic reconstruction to reveal nine major SPL gene lineages, each of which is described in terms of function and diversification. To assess evidence for ancestral and derived functions within each SPL gene lineage, we use ancestral character state reconstructions. Our analyses suggest an emerging pattern of sub-functionalization, neo-functionalization, and possible convergent evolution following both ancient and recent gene duplication. Based on these analyses we suggest future avenues of research that may prove fruitful for elucidating the importance of SPL gene evolution in plant growth and development.

  3. Linkage disequilibrium, genetic association mapping and gene localization in crop plants

    Directory of Open Access Journals (Sweden)

    Karim Sorkheh

    2008-12-01

    Full Text Available DNA-based molecular markers have been extensively utilized for a variety of studies in both plant and animal systems. One of the major uses of these markers is the construction of genome-wide molecular maps and the genetic analysis of simple and complex traits. However, these studies are generally based on linkage analysis in mapping populations, thus placing serious limitations in using molecular markers for genetic analysis in a variety of plant populations. Therefore, alternative approach has been suggested, linkage disequilibrium-based association analysis which detects and locates quantitative trait loci (QTL by the strength of the correlation between a trait and a marker. Although association analysis has already been used for studies on genetics of complex traits in humans, its use in plants has newly started. In the present review, we describe what is known about variation in linkage disequilibrium (LD and summarize published results on association studies in crop plant species. We give a list of different factors affecting LD, and discuss the current issues of LD research in plants. Later, we also describe the various uses of LD in crop plants research and summarize the present status of LD researches in different plant genomes. Finally, future key issues about the application of these studies on the localization of genes in these crop plants have been also discussed.

  4. Taller plants have lower rates of molecular evolution.

    Science.gov (United States)

    Lanfear, Robert; Ho, Simon Y W; Jonathan Davies, T; Moles, Angela T; Aarssen, Lonnie; Swenson, Nathan G; Warman, Laura; Zanne, Amy E; Allen, Andrew P

    2013-01-01

    Rates of molecular evolution have a central role in our understanding of many aspects of species' biology. However, the causes of variation in rates of molecular evolution remain poorly understood, particularly in plants. Here we show that height accounts for about one-fifth of the among-lineage rate variation in the chloroplast and nuclear genomes of plants. This relationship holds across 138 families of flowering plants, and when accounting for variation in species richness, temperature, ultraviolet radiation, latitude and growth form. Our observations can be explained by a link between height and rates of genome copying in plants, and we propose a mechanistic hypothesis to account for this-the 'rate of mitosis' hypothesis. This hypothesis has the potential to explain many disparate observations about rates of molecular evolution across the tree of life. Our results have implications for understanding the evolutionary history and future of plant lineages in a changing world.

  5. Impact of Cropping Systems, Soil Inoculum, and Plant Species Identity on Soil Bacterial Community Structure.

    Science.gov (United States)

    Ishaq, Suzanne L; Johnson, Stephen P; Miller, Zach J; Lehnhoff, Erik A; Olivo, Sarah; Yeoman, Carl J; Menalled, Fabian D

    2017-02-01

    Farming practices affect the soil microbial community, which in turn impacts crop growth and crop-weed interactions. This study assessed the modification of soil bacterial community structure by organic or conventional cropping systems, weed species identity [Amaranthus retroflexus L. (redroot pigweed) or Avena fatua L. (wild oat)], and living or sterilized inoculum. Soil from eight paired USDA-certified organic and conventional farms in north-central Montana was used as living or autoclave-sterilized inoculant into steam-pasteurized potting soil, planted with Am. retroflexus or Av. fatua and grown for two consecutive 8-week periods to condition soil nutrients and biota. Subsequently, the V3-V4 regions of the microbial 16S rRNA gene were sequenced by Illumina MiSeq. Treatments clustered significantly, with living or sterilized inoculum being the strongest delineating factor, followed by organic or conventional cropping system, then individual farm. Living inoculum-treated soil had greater species richness and was more diverse than sterile inoculum-treated soil (observed OTUs, Chao, inverse Simpson, Shannon, P Organically farmed inoculum-treated soil had greater species richness, more diversity (observed OTUs, Chao, Shannon, P conventionally farmed inoculum-treated soil. Cyanobacteria were higher in pots growing Am. retroflexus, regardless of inoculum type, for three of the four organic farms. Results highlight the potential of cropping systems and species identity to modify soil bacterial communities, subsequently modifying plant growth and crop-weed competition.

  6. Horizontal Gene Transfer Contributes to Plant Evolution: The Case of Agrobacterium T-DNAs

    Directory of Open Access Journals (Sweden)

    Dora G. Quispe-Huamanquispe

    2017-11-01

    Full Text Available Horizontal gene transfer (HGT can be defined as the acquisition of genetic material from another organism without being its offspring. HGT is common in the microbial world including archaea and bacteria, where HGT mechanisms are widely understood and recognized as an important force in evolution. In eukaryotes, HGT now appears to occur more frequently than originally thought. Many studies are currently detecting novel HGT events among distinct lineages using next-generation sequencing. Most examples to date include gene transfers from bacterial donors to recipient organisms including fungi, plants, and animals. In plants, one well-studied example of HGT is the transfer of the tumor-inducing genes (T-DNAs from some Agrobacterium species into their host plant genomes. Evidence of T-DNAs from Agrobacterium spp. into plant genomes, and their subsequent maintenance in the germline, has been reported in Nicotiana, Linaria and, more recently, in Ipomoea species. The transferred genes do not produce the usual disease phenotype, and appear to have a role in evolution of these plants. In this paper, we review previous reported cases of HGT from Agrobacterium, including the transfer of T-DNA regions from Agrobacterium spp. to the sweetpotato [Ipomoea batatas (L. Lam.] genome which is, to date, the sole documented example of a naturally-occurring incidence of HGT from Agrobacterium to a domesticated crop plant. We also discuss the possible evolutionary impact of T-DNA acquisition on plants.

  7. Horizontal Gene Transfer Contributes to Plant Evolution: The Case ofAgrobacteriumT-DNAs.

    Science.gov (United States)

    Quispe-Huamanquispe, Dora G; Gheysen, Godelieve; Kreuze, Jan F

    2017-01-01

    Horizontal gene transfer (HGT) can be defined as the acquisition of genetic material from another organism without being its offspring. HGT is common in the microbial world including archaea and bacteria, where HGT mechanisms are widely understood and recognized as an important force in evolution. In eukaryotes, HGT now appears to occur more frequently than originally thought. Many studies are currently detecting novel HGT events among distinct lineages using next-generation sequencing. Most examples to date include gene transfers from bacterial donors to recipient organisms including fungi, plants, and animals. In plants, one well-studied example of HGT is the transfer of the tumor-inducing genes (T-DNAs) from some Agrobacterium species into their host plant genomes. Evidence of T-DNAs from Agrobacterium spp. into plant genomes, and their subsequent maintenance in the germline, has been reported in Nicotiana , Linaria and, more recently, in Ipomoea species. The transferred genes do not produce the usual disease phenotype, and appear to have a role in evolution of these plants. In this paper, we review previous reported cases of HGT from Agrobacterium , including the transfer of T-DNA regions from Agrobacterium spp. to the sweetpotato [ Ipomoea batatas (L.) Lam.] genome which is, to date, the sole documented example of a naturally-occurring incidence of HGT from Agrobacterium to a domesticated crop plant. We also discuss the possible evolutionary impact of T-DNA acquisition on plants.

  8. The fascinating facets of plant selenium accumulation - biochemistry, physiology, evolution and ecology.

    Science.gov (United States)

    Schiavon, Michela; Pilon-Smits, Elizabeth A H

    2017-03-01

    Contents 1582 I. 1582 II. 1583 III. 1588 IV. 1590 V. 1592 1592 References 1592 SUMMARY: The importance of selenium (Se) for medicine, industry and the environment is increasingly apparent. Se is essential for many species, including humans, but toxic at elevated concentrations. Plant Se accumulation and volatilization may be applied in crop biofortification and phytoremediation. Topics covered here include beneficial and toxic effects of Se on plants, mechanisms of Se accumulation and tolerance in plants and algae, Se hyperaccumulation, and ecological and evolutionary aspects of these processes. Plant species differ in the concentration and forms of Se accumulated, Se partitioning at the whole-plant and tissue levels, and the capacity to distinguish Se from sulfur. Mechanisms of Se hyperaccumulation and its adaptive significance appear to involve constitutive up-regulation of sulfate/selenate uptake and assimilation, associated with elevated concentrations of defense-related hormones. Hyperaccumulation has evolved independently in at least three plant families, probably as an elemental defense mechanism and perhaps mediating elemental allelopathy. Elevated plant Se protects plants from generalist herbivores and pathogens, but also gives rise to the evolution of Se-resistant specialists. Plant Se accumulation affects ecological interactions with herbivores, pollinators, neighboring plants, and microbes. Hyperaccumulation tends to negatively affect Se-sensitive ecological partners while facilitating Se-resistant partners, potentially affecting species composition and Se cycling in seleniferous ecosystems. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  9. Integrated genomics and molecular breeding approaches for dissecting the complex quantitative traits in crop plants.

    Science.gov (United States)

    Kujur, Alice; Saxena, Maneesha S; Bajaj, Deepak; Laxmi; Parida, Swarup K

    2013-12-01

    The enormous population growth, climate change and global warming are now considered major threats to agriculture and world's food security. To improve the productivity and sustainability of agriculture, the development of highyielding and durable abiotic and biotic stress-tolerant cultivars and/climate resilient crops is essential. Henceforth, understanding the molecular mechanism and dissection of complex quantitative yield and stress tolerance traits is the prime objective in current agricultural biotechnology research. In recent years, tremendous progress has been made in plant genomics and molecular breeding research pertaining to conventional and next-generation whole genome, transcriptome and epigenome sequencing efforts, generation of huge genomic, transcriptomic and epigenomic resources and development of modern genomics-assisted breeding approaches in diverse crop genotypes with contrasting yield and abiotic stress tolerance traits. Unfortunately, the detailed molecular mechanism and gene regulatory networks controlling such complex quantitative traits is not yet well understood in crop plants. Therefore, we propose an integrated strategies involving available enormous and diverse traditional and modern -omics (structural, functional, comparative and epigenomics) approaches/resources and genomics-assisted breeding methods which agricultural biotechnologist can adopt/utilize to dissect and decode the molecular and gene regulatory networks involved in the complex quantitative yield and stress tolerance traits in crop plants. This would provide clues and much needed inputs for rapid selection of novel functionally relevant molecular tags regulating such complex traits to expedite traditional and modern marker-assisted genetic enhancement studies in target crop species for developing high-yielding stress-tolerant varieties.

  10. Aluminium toxicity tolerance in crop plants: Present status of research

    African Journals Online (AJOL)

    Soil acidity is one of the major constraints to agricultural production in large parts around the world. In acid soils, aluminium toxicity and consequent low phosphorous availability impair plant growth. The primary response to aluminium stress is visible in the roots. Exclusion and neutralization are two well known mechanism ...

  11. Volatile Semiochemical Mediated Plant Defense in Cereals: A Novel Strategy for Crop Protection

    Directory of Open Access Journals (Sweden)

    Amanuel Tamiru

    2017-09-01

    Full Text Available Plants have evolved highly intriguing ways of defending themselves against insect attacks, including through emission of defense volatiles. These volatiles serve the plant’s defense by directly repelling phytophagous insects and/or indirectly through attracting natural enemies antagonistic to the herbivores. Several laboratory studies established the potential of improving plant resistance against insect attacks by manipulating the plant-derived volatile semiochemicals emissions. Yet, more efforts need to be conducted to translate the promising laboratory studies to fight economically-important crop pests under real field conditions. This is needed to address an increasing demand for alternative pest control options driven by ecological and environmental costs associated with the use of broad-spectrum insecticides. The practical examples discussed in this review paper demonstrate the real prospect of exploiting an inducible and constitutive plant volatile semiochemicals for developing novel and ecologically-sustainable pest management strategies to protect cereal crops from damaging insect pests.

  12. The plant vascular system: Evolution, development and functions

    Science.gov (United States)

    William J. Lucas; Andrew Groover; Raffael Lichtenberger; Kaori Furuta; Shri-Ram Yadav; Yka Helariutta; Xin-Qiang He; Hiroo Fukuda; Julie Kang; Siobhan M. Brady; John W. Patrick; John Sperry; Akiko Yoshida; Ana-Flor Lopez-Millan; Michael A. Grusak; Pradeep Kachroo

    2013-01-01

    The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of environmental habitats. Recently, considerable progress has been made...

  13. Regulating transgenic crops sensibly: lessons from plant breeding, biotechnology and genomics.

    Science.gov (United States)

    Bradford, Kent J; Van Deynze, Allen; Gutterson, Neal; Parrott, Wayne; Strauss, Steven H

    2005-04-01

    The costs of meeting regulatory requirements and market restrictions guided by regulatory criteria are substantial impediments to the commercialization of transgenic crops. Although a cautious approach may have been prudent initially, we argue that some regulatory requirements can now be modified to reduce costs and uncertainty without compromising safety. Long-accepted plant breeding methods for incorporating new diversity into crop varieties, experience from two decades of research on and commercialization of transgenic crops, and expanding knowledge of plant genome structure and dynamics all indicate that if a gene or trait is safe, the genetic engineering process itself presents little potential for unexpected consequences that would not be identified or eliminated in the variety development process before commercialization. We propose that as in conventional breeding, regulatory emphasis should be on phenotypic rather than genomic characteristics once a gene or trait has been shown to be safe.

  14. Evolution Is an Experiment: Assessing Parallelism in Crop Domestication and Experimental Evolution: (Nei Lecture, SMBE 2014, Puerto Rico).

    Science.gov (United States)

    Gaut, Brandon S

    2015-07-01

    In this commentary, I make inferences about the level of repeatability and constraint in the evolutionary process, based on two sets of replicated experiments. The first experiment is crop domestication, which has been replicated across many different species. I focus on results of whole-genome scans for genes selected during domestication and ask whether genes are, in fact, selected in parallel across different domestication events. If genes are selected in parallel, it implies that the number of genetic solutions to the challenge of domestication is constrained. However, I find no evidence for parallel selection events either between species (maize vs. rice) or within species (two domestication events within beans). These results suggest that there are few constraints on genetic adaptation, but conclusions must be tempered by several complicating factors, particularly the lack of explicit design standards for selection screens. The second experiment involves the evolution of Escherichia coli to thermal stress. Unlike domestication, this highly replicated experiment detected a limited set of genes that appear prone to modification during adaptation to thermal stress. However, the number of potentially beneficial mutations within these genes is large, such that adaptation is constrained at the genic level but much less so at the nucleotide level. Based on these two experiments, I make the general conclusion that evolution is remarkably flexible, despite the presence of epistatic interactions that constrain evolutionary trajectories. I also posit that evolution is so rapid that we should establish a Speciation Prize, to be awarded to the first researcher who demonstrates speciation with a sexual organism in the laboratory. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Photosynthesis of crop plants as influenced by light, carbon dioxide, temperature, and stomatal diffusion resistance

    NARCIS (Netherlands)

    Gaastra, P.

    1959-01-01

    The effect was estimated of light intensity, leaf temperature, and C0 2 concentration on photosynthetic rate in leaves of crop plants. The potential capacities of photochemical and biochemical processes and of C0 2 transport were compared.

    Resistance to C0 2

  16. Accurate measure of transgene copy number in crop plants using droplet digital PCR

    Science.gov (United States)

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy numb...

  17. Nematode Interactions in Nature: Models for Sustainable Control of Nematode Pests of Crop Plants?

    NARCIS (Netherlands)

    Putten, van der W.H.; Cook, R.; Costa, S.; Davies, K.G.; Fargette, M.; Freitas, H.; Hol, W.H.G.; Kerry, B.R.; Maher, N.; Mateille, T.; Moens, M.; Peña, de la E.; Piskiewicz, A.M.; Raeymaekers, A.D.W.; Rodriquez-Echeverria, S.; Wurff, van der A.W.G.

    2006-01-01

    Plant-parasitic nematodes are major crop pests in agro-ecosystems while in nature their impact may range from substantial to no significant growth reduction. The aim of this review is to determine if nematode population control in natural ecosystems may provide us with a model for enhancing

  18. Nematode interactions in nature: models for sustainable control of nematode pests of crop plants?

    NARCIS (Netherlands)

    Van der Putten, W.H.; Cook, R.; Costa, S.R.; Davies, K.G.; Fargette, M.; Freitas, H.; Hol, W.H.G.; Kerry, B.R.; Maher, N.; Mateille, T.; Moens, M.; De la Peña, E.; Piskiewicz, A.; Raeymaekers, A.; Rodríguez-Echeverría, S.; Van der Wurff, A.W.G.

    2006-01-01

    Plant-parasitic nematodes are major crop pests in agro-ecosystems while in nature their impact may range from substantial to no significant growth reduction. The aim of this review is to determine if nematode population control in natural ecosystems may provide us with a model for enhancing

  19. Host plant preference of Lygus hesperus exposed to three desert-adapted industrial crops

    Science.gov (United States)

    The desert-adapted crops vernonia (Centrapalus pauciflorus), lesquerella (Physaria fendleri), and camelina (Camelina sativa) are being grown in the arid southwestern USA as potential feedstock for biofuel and/or other environmentally friendly products. A plant feeding choice test was conducted to de...

  20. A crop growth simulation model for operational management support in pot plant production.

    NARCIS (Netherlands)

    Leutscher, K.J.; Vogelezang, J.V.M.

    1990-01-01

    The elaboration of a crop growth model for pot plant production which takes account of the physiological processes controlling growth and yet is suitable for management purposes is described. The parameters of the model are specified for Schefflera arboricola cv. Compacta using

  1. Accurate measurement of transgene copy number in crop plants using droplet digital PCR

    Science.gov (United States)

    Technical abstract: Genetic transformation is a powerful means for the improvement of crop plants, but requires labor and resource intensive methods. An efficient method for identifying single copy transgene insertion events from a population of independent transgenic lines is desirable. Currently ...

  2. Magnetic field effects on plant growth, development and evolution

    Directory of Open Access Journals (Sweden)

    Massimo E. Maffei

    2014-09-01

    Full Text Available The geomagnetic field (GMF is a natural component of our environment. Plants, which are known to sense different wavelengths of light, respond to gravity, react to touch and electrical signaling, cannot escape the effect of GMF. While phototropism, gravitropism, and tigmotropism have been thoroughly studied, the impact of GMF on plant growth and development is not well understood. This review describes the effects of altering MF conditions on plants by considering plant responses to MF values either lower or higher than those of the GMF. The possible role of GMF on plant evolution and the nature of the magnetoreceptor is also discussed.

  3. Evolution of the future plants operation for a better safety

    Energy Technology Data Exchange (ETDEWEB)

    Papin, B.; Malvache, P.

    1994-12-31

    This paper describes a coordinated research project of the french CEA, addressing to the evolutions in plant operation apt to bring perceptible and assessable improvement in the operational safety. This program has been scheduled for the 1992-1996 period, with a global 40 men/year effort. The present status of the two main parts of the project is presented: ESCRIME (program aiming at defining the optimal share of tasks between humans and computers in plant operation), IMAGIN (research in the domain of plant information management, in order to ensure the global coherence of the image of the plant, used by the different actors in plant operation). (authors). 3 refs., 4 figs.

  4. Plant Productivity and Characterization of Zeoponic Substrates after Three Successive Crops of Radish (Raphanus sativus L.)

    Science.gov (United States)

    Gruener, J. E.; Ming, Douglas W.; Galindo, C., Jr.; Henderson, K. E.; Golden, D. C.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) has developed a zeolite-based synthetic substrate, termed zeoponics. The zeoponic substrate (consisting of NH4(-) and K-exchanged clinoptilolite, synthetic apatite, and dolomite) provides all of the plant-essential nutrients through mineral dissolution and ion exchange, with only the addition of water. Previous studies have shown high productivity of wheat in zeoponic substrates; however, no experiments have been conducted on other crops. The objective of this study was to determine the productivity and nutrient uptake of radish (Raphanus sativus L.) grown in zeoponic substrates with three successive crops in the same substrate. Radish was chosen because of its sensitivities to NH4(+). Average fresh weights of edible roots were similar for radish grown in zeoponic substrates watered with deionized H2O (10.97 g/plant) and in potting mix control substrate irrigated with nutrient solution (10.92 g/plant). Average fresh weight production of edible roots for radish grown in same zeoponic substrate increased in yield over time with the lowest yield in the first crop (7.10 g/plant) and highest in the third crop (13.90 g/plant). The Ca plant tissue levels in radishes (1.8-2.9 wt. %) grown in zeoponic substrates are lower than the suggested sufficient range of 3.0-4.5 wt. % Ca; however, the Ca level is highest (2.9 wt. %) in radishes grown in the third crop in the same zeoponic substrates. The higher radish yield in the third crop was attributed to a reduction in an NH4(-) induced Ca deficiency that has been previously described for wheat grown in zeoponic substrates. The P levels in plant tissues of radish grown in the zeoponic substrates ranged from 0.94-1.15 wt. %; which is slightly higher than the sufficient levels of 0.3-0.7 wt. %. With the exception of Ca and P, other macronutrient and micronutrient levels in radish grown in zeoponic substrates were well within the recommended sufficient ranges. After three

  5. plant: A package for modelling forest trait ecology and evolution

    OpenAIRE

    Falster, D.S.; FitzJohn, R.G.; Brännström, Å; Dieckmann, U.; Westoby, M; McMahon, S

    2016-01-01

    1. Population dynamics in forests are strongly size-structured: larger plants shade smaller plants while also expending proportionately more energy on building and maintaining woody stems. Although the importance of size structure for demography is widely recognized, many models either omit it entirely or include only coarse approximations. 2. Here, we introduce the plant package, an extensible framework for modelling size- and trait-structured demography, ecology and evolution in simulat...

  6. Biogeographic, molecular evolution, and diversification patterns in Neotropical plants

    Science.gov (United States)

    Smith, S. A.; Dick, C. W.

    2014-12-01

    Neotropical plants demonstrate a phenomenal range of ecological and morphological diversity. We will explore the phylogenetic and biogeographic patterns of a group of Neotropical plants and how these patterns relate to the geological history of the area. This includes the timing and location of biological exchange between areas. Neotropical plants also demonstrate repeated examples of rapid speciation and diversification. We will examine these evolutionary patterns and how they relate to molecular evolution.

  7. PLANT EVOLUTION. Convergent evolution of strigolactone perception enabled host detection in parasitic plants.

    Science.gov (United States)

    Conn, Caitlin E; Bythell-Douglas, Rohan; Neumann, Drexel; Yoshida, Satoko; Whittington, Bryan; Westwood, James H; Shirasu, Ken; Bond, Charles S; Dyer, Kelly A; Nelson, David C

    2015-07-31

    Obligate parasitic plants in the Orobanchaceae germinate after sensing plant hormones, strigolactones, exuded from host roots. In Arabidopsis thaliana, the α/β-hydrolase D14 acts as a strigolactone receptor that controls shoot branching, whereas its ancestral paralog, KAI2, mediates karrikin-specific germination responses. We observed that KAI2, but not D14, is present at higher copy numbers in parasitic species than in nonparasitic relatives. KAI2 paralogs in parasites are distributed into three phylogenetic clades. The fastest-evolving clade, KAI2d, contains the majority of KAI2 paralogs. Homology models predict that the ligand-binding pockets of KAI2d resemble D14. KAI2d transgenes confer strigolactone-specific germination responses to Arabidopsis thaliana. Thus, the KAI2 paralogs D14 and KAI2d underwent convergent evolution of strigolactone recognition, respectively enabling developmental responses to strigolactones in angiosperms and host detection in parasites. Copyright © 2015, American Association for the Advancement of Science.

  8. Molecular breeding to create optimized crops: from genetic manipulation to potential applications in plant factories

    Directory of Open Access Journals (Sweden)

    Kyoko eHiwasa-Tanase

    2016-04-01

    Full Text Available Crop cultivation in controlled environment plant factories offers great potential to stabilize the yield and quality of agricultural products. However, many crops are currently unsuited to these environments, particularly closed cultivation systems, due to space limitations, low light intensity, high implementation costs, and high energy requirements. A major barrier to closed system cultivation is the high running cost, which necessitates the use of high-margin crops for economic viability. High-value crops include those with enhanced nutritional value or containing additional functional components for pharmaceutical production or with the aim of providing health benefits. In addition, it is important to develop cultivars equipped with growth parameters that are suitable for closed cultivation. Small plant size is of particular importance due to the limited cultivation space. Other advantageous traits are short production cycle, the ability to grow under low light, and high nutriculture availability. Cost-effectiveness is improved from the use of cultivars that are specifically optimized for closed system cultivation. This review describes the features of closed cultivation systems and the potential application of molecular breeding to create crops that are optimized for cost-effectiveness and productivity in closed cultivation systems.

  9. Soil erosion control, plant diversity, and arthropod communities under heterogeneous cover crops in an olive orchard.

    Science.gov (United States)

    Gómez, José Alfonso; Campos, Mercedes; Guzmán, Gema; Castillo-Llanque, Franco; Vanwalleghem, Tom; Lora, Ángel; Giráldez, Juan V

    2018-01-01

    A 3-year experiment compared in an olive orchard the effect of different cover crops' composition on runoff, water erosion, diversity of annual plants, and arthropod communities which could provide an alternative to conventional management based on tillage (CT). The cover crops evaluated were a seeded homogeneous grass (GC), a seeded mix of ten different species (MCseeded), and a non-seeded cover by vegetation naturally present at the farm after 20 years of mowing (MCnatural). The results suggest that heterogeneous cover crops can provide a viable alternative to homogeneous ones in olives, providing similar benefits in reducing runoff and soil losses compared to management based on bare soil. The reduction in soil loss was particularly large: 46.7 in CT to 6.5 and 7.9 t ha-1 year-1 in GC and MCseeded, respectively. The heterogeneous cover crops resulted in greater diversity of plant species and a modification of the arthropod communities with an increased number of predators for pests. The reduction of the cost of implanting heterogeneous cover crops, improvement of the seeding techniques, and selection of species included in the mixes require additional research to promote the use of this practice which can deliver enhanced environmental benefits.

  10. Advances in plant proteomics towards improvement of crop productivity and stress resistance

    Directory of Open Access Journals (Sweden)

    Junjie eHu

    2015-04-01

    Full Text Available Abiotic and biotic stresses constrain plant growth and development negatively impacting crop production. Plants have developed stress-specific adaptations as well as simultaneous responses to a combination of various abiotic stresses with pathogen infection. The efficiency of stress-induced adaptive responses is dependent on activation of molecular signaling pathways and intracellular networks by modulating expression, or abundance, and/or posttranslational modification of proteins primarily associated with defense mechanisms. In this review, we summarize and evaluate the contribution of proteomic studies to our understanding of stress response mechanisms in different plant organs and tissues. Advanced quantitative proteomic techniques have improved the coverage of total proteomes and sub-proteomes from small amounts of starting material, and characterized post-translational modifications as well as protein–protein interactions at the cellular level, providing detailed information on organ- and tissue-specific regulatory mechanisms responding to a variety of individual stresses or stress combinations during plant life cycle. In particular, we address the tissue-specific signaling networks localized to various organelles that participate in stress-related physiological plasticity and adaptive mechanisms, such as photosynthetic efficiency, symbiotic nitrogen fixation, plant growth, tolerance and common responses to environmental stresses. We also provide an update on the progress of proteomics with major crop species and discuss the current challenges and limitations inherent to proteomics techniques and data interpretation for non-model organisms. Future directions in proteomics research towards crop improvement are further discussed.

  11. Transposable elements and genetic instabilities in crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Burr, B.; Burr, F.

    1981-04-10

    Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.

  12. [The application of genome editing in identification of plant gene function and crop breeding].

    Science.gov (United States)

    Zhou, Xiang-chun; Xing, Yong-zhong

    2016-03-01

    Plant genome can be modified via current biotechnology with high specificity and excellent efficiency. Zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALEN) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system are the key engineered nucleases used in the genome editing. Genome editing techniques enable gene targeted mutagenesis, gene knock-out, gene insertion or replacement at the target sites during the endogenous DNA repair process, including non-homologous end joining (NHEJ) and homologous recombination (HR), triggered by the induction of DNA double-strand break (DSB). Genome editing has been successfully applied in the genome modification of diverse plant species, such as Arabidopsis thaliana, Oryza sativa, and Nicotiana tabacum. In this review, we summarize the application of genome editing in identification of plant gene function and crop breeding. Moreover, we also discuss the improving points of genome editing in crop precision genetic improvement for further study.

  13. Understanding and engineering beneficial plant–microbe interactions: plant growth promotion in energy crops

    Science.gov (United States)

    Farrar, Kerrie; Bryant, David; Cope-Selby, Naomi

    2014-01-01

    Plant production systems globally must be optimized to produce stable high yields from limited land under changing and variable climates. Demands for food, animal feed, and feedstocks for bioenergy and biorefining applications, are increasing with population growth, urbanization and affluence. Low-input, sustainable, alternatives to petrochemical-derived fertilizers and pesticides are required to reduce input costs and maintain or increase yields, with potential biological solutions having an important role to play. In contrast to crops that have been bred for food, many bioenergy crops are largely undomesticated, and so there is an opportunity to harness beneficial plant–microbe relationships which may have been inadvertently lost through intensive crop breeding. Plant–microbe interactions span a wide range of relationships in which one or both of the organisms may have a beneficial, neutral or negative effect on the other partner. A relatively small number of beneficial plant–microbe interactions are well understood and already exploited; however, others remain understudied and represent an untapped reservoir for optimizing plant production. There may be near-term applications for bacterial strains as microbial biopesticides and biofertilizers to increase biomass yield from energy crops grown on land unsuitable for food production. Longer term aims involve the design of synthetic genetic circuits within and between the host and microbes to optimize plant production. A highly exciting prospect is that endosymbionts comprise a unique resource of reduced complexity microbial genomes with adaptive traits of great interest for a wide variety of applications. PMID:25431199

  14. The Evolution of Sex Chromosomes and Dosage Compensation in Plants

    Science.gov (United States)

    Shearn, Rylan; Marais, Gabriel AB

    2017-01-01

    Plant sex chromosomes can be vastly different from those of the few historical animal model organisms from which most of our understanding of sex chromosome evolution is derived. Recently, we have seen several advancements from studies on green algae, brown algae, and land plants that are providing a broader understanding of the variable ways in which sex chromosomes can evolve in distant eukaryotic groups. Plant sex-determining genes are being identified and, as expected, are completely different from those in animals. Species with varying levels of differentiation between the X and Y have been found in plants, and these are hypothesized to be representing different stages of sex chromosome evolution. However, we are also finding that sex chromosomes can remain morphologically unchanged over extended periods of time. Where degeneration of the Y occurs, it appears to proceed similarly in plants and animals. Dosage compensation (a phenomenon that compensates for the consequent loss of expression from the Y) has now been documented in a plant system, its mechanism, however, remains unknown. Research has also begun on the role of sex chromosomes in sexual conflict resolution, and it appears that sex-biased genes evolve similarly in plants and animals, although the functions of these genes remain poorly studied. Because the difficulty in obtaining sex chromosome sequences is increasingly being overcome by methodological developments, there is great potential for further discovery within the field of plant sex chromosome evolution. PMID:28391324

  15. An Alternative Use of Horticultural Crops: Stressed Plants as Biofactories of Bioactive Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Luis Cisneros-Zevallos

    2012-09-01

    Full Text Available Plants subjected to abiotic stresses synthesize secondary metabolites with potential application in the functional foods, dietary supplements, pharmaceutical, cosmetics and agrochemical markets. This approach can be extended to horticultural crops. This review describes previous reports regarding the effect of different postharvest abiotic stresses on the accumulation of phenolic compounds. Likewise, the physiological basis for the biosynthesis of phenolic compounds as an abiotic stress response is described. The information presented herein would be useful for growers and the fresh produce market which are interested in finding alternative uses for their crops, especially for those not meeting quality standards and thus are considered as waste.

  16. Genetic engineering for increasing fungal and bacterial disease resistance in crop plants.

    Science.gov (United States)

    Wally, Owen; Punja, Zamir K

    2010-01-01

    We review the current and future potential of genetic engineering strategies used to make fungal and bacterial pathogen-resistant GM crops, illustrating different examples of the technologies and the potential benefits and short-falls of the strategies. There are well- established procedures for the production of transgenic plants with resistance towards these pathogens and considerable progress has been made using a range of new methodologies. There are no current commercially available transgenic plant species with increased resistance towards fungal and bacterial pathogens; only plants with increased resistance towards viruses are available. With an improved understanding of plant signaling pathways in response to a range of other pathogens, such as fungi, additional candidate genes for achieving resistance are being investigated. The potential for engineering plants for resistance against individual devastating diseases or for plants with resistance towards multiple pathogens is discussed in detail.

  17. Repeated evolution of crop theft in fungus-farming ambrosia beetles.

    Science.gov (United States)

    Hulcr, Jiri; Cognato, Anthony I

    2010-11-01

    Ambrosia beetles, dominant wood degraders in the tropics, create tunnels in dead trees and employ gardens of symbiotic fungi to extract nutrients from wood. Specificity of the beetle-fungus relationship has rarely been examined, and simple vertical transmission of a specific fungal cultivar by each beetle species is often assumed in literature. We report repeated evolution of fungal crop stealing, termed mycocleptism, among ambrosia beetles. The mycocleptic species seek brood galleries of other species, and exploit their established fungal gardens by tunneling through the ambient mycelium-laden wood. Instead of carrying their own fungal sybmbionts, mycocleptae depend on adopting the fungal assemblages of their host species, as shown by an analysis of fungal DNA from beetle galleries. The evidence for widespread horizontal exchange of fungi between beetles challenges the traditional concept of ambrosia fungi as species-specific symbionts. Fungus stealing appears to be an evolutionarily successful strategy. It evolved independently in several beetle clades, two of which have radiated, and at least one case was accompanied by a loss of the beetles' fungus-transporting organs. We demonstrate this using the first robust phylogeny of one of the world's largest group of ambrosia beetles, Xyleborini. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  18. Cover Image Identification of Plant Species for Crop Pollinator Habitat Enhancement in the Northern Prairies

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    Diana Bizecki Robson

    2014-09-01

    Full Text Available Wild pollinators have a positive impact on the productivity of insect-pollinated crops. Consequently, landowners are being encouraged to maintain and grow wildflower patches to provide habitat for important pollinators. Research on plant-pollinator interaction matrices indicates that a small number of “core” plants provide a disproportionately high amount of pollen and nectar to insects. This matrix data can be used to help design wildflower plantings that provide optimal resources for desirable pollinators. Existing interaction matrices from three tall grass prairie preserves in the northern prairies were used to identify core plant species that are visited by wild pollinators of a common insect-pollinated crop, namely canola (Brassica napus L.. The wildflower preferences of each insect taxon were determined using quantitative insect visitation and floral abundance data. Phenology data were used to calculate the degree of floral synchrony between the wildflowers and canola. Using this information I ranked the 41 wildflowers that share insect visitors with canola according to how useful they are for providing pollinators with forage before and after canola flowers. The top five species were smooth blue aster (Symphyotrichum laeve (L. A. & D. Löve, stiff goldenrod (Solidago rigida L., wild bergamot (Monarda fistulosa L., purple prairie-clover (Dalea purpurea Vent. and Lindley’s aster (Symphyotrichum ciliolatum (Lindl. A. & D. Löve. By identifying the most important wild insects for crop pollination, and determining when there will be “pollen and nectar gaps”, appropriate plant species can be selected for companion plantings to increase pollinator populations and crop production.

  19. DNA damage and repair in plants – from models to crops

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    Vasilissa eManova

    2015-10-01

    Full Text Available The genomic integrity of every organism is constantly challenged by endogenous and exogenous DNA-damaging factors. Mutagenic agents cause reduced stability of plant genome and have a deleterious effect on development, and in the case of crop species lead to yield reduction. It is crucial for all organisms, including plants, to develop efficient mechanisms for maintenance of the genome integrity. DNA repair processes have been characterized in bacterial, fungal and mammalian model systems. The description of these processes in plants, in contrast, was initiated relatively recently and has been focused largely on the model plant Arabidopsis thaliana. Consequently, our knowledge about DNA repair in plant genomes- particularly in the genomes of crops plants- is by far more limited. However, the relatively small size of the Arabidopsis genome, its rapid life cycle and availability of various transformation methods make this species an attractive model for the study of eukaryotic DNA repair mechanisms and mutagenesis. Moreover, abnormalities in DNA repair which proved to be lethal for animal models are tolerated in plant genomes, although sensitivity to DNA damaging agents is retained. Due to the high conservation of DNA repair processes and factors mediating them among eukaryotes, genes and proteins that have been identified in model species may serve to identify homologous sequences in other species, including crop plants, in which these mechanisms are poorly understood. Crop breeding programs have provided remarkable advances in food quality and yield over the last century. Although the human population is predicted to peak by 2050, further advances in yield will be required to feed this population. Breeding requires genetic diversity. The biological impact of any mutagenic agent used for the creation of genetic diversity depends on the chemical nature of the induced lesions and on the efficiency and accuracy of their repair. More recent targeted

  20. Evolution of plant sucrose uptake transporters (SUTs

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    Anke eReinders

    2012-02-01

    Full Text Available In angiosperms, sucrose uptake transporters (SUTs have important functions especially in vascular tissue. Here we explore the evolutionary origins of SUTs by analysis of angiosperm SUTs and homologous transporters in a vascular early land plant, Selaginella moellendorffii, and a non-vascular plant, the bryophyte Physcomitrella patens, the charophyte algae Chlorokybus atmosphyticus, several red algae and fission yeast, Schizosaccharomyces pombe. Plant SUTs cluster into three types by phylogenetic analysis. Previous studies using angiosperms had shown that Types I and II are localized to plasma membrane while type III SUTs are associated with vacuolar membrane. SUT homologs were not found in the chlorophyte algae Chlamydomonas reinhardtii and Volvox carterii. However, the characean algae Chlorokybus atmosphyticus contains a SUT homolog (CaSUT1 and phylogenetic analysis indicated that it is basal to all other streptophyte SUTs analyzed. SUTs are present in both red algae and S. pombe but are less related to plant SUTs than CaSUT1. Both Selaginella and Physcomitrella encode type II and III SUTs suggesting that both plasma membrane and vacuolar sucrose transporter activities were present in early land plants. It is likely that SUT transporters are important for scavenging sucrose from the environment and intracellular compartments in charophyte and non-vascular plants. Type I SUTs were only found in eudicots and we conclude that they evolved from type III SUTs, possibly through loss of a vacuolar targeting sequence. Eudicots utilize type I SUTs for phloem (vascular tissue loading while monocots use type II SUTs for phloem loading. We show that HvSUT1 from barley, a type II SUT, reverted the growth defect of the Arabidopsis atsuc2 (type I mutant. This indicates that SUTs evolved similar (and interchangeable phloem loading transporter capabilities independently.

  1. Evolution and genome architecture in fungal plant pathogens.

    Science.gov (United States)

    Möller, Mareike; Stukenbrock, Eva H

    2017-12-01

    The fungal kingdom comprises some of the most devastating plant pathogens. Sequencing the genomes of fungal pathogens has shown a remarkable variability in genome size and architecture. Population genomic data enable us to understand the mechanisms and the history of changes in genome size and adaptive evolution in plant pathogens. Although transposable elements predominantly have negative effects on their host, fungal pathogens provide prominent examples of advantageous associations between rapidly evolving transposable elements and virulence genes that cause variation in virulence phenotypes. By providing homogeneous environments at large regional scales, managed ecosystems, such as modern agriculture, can be conducive for the rapid evolution and dispersal of pathogens. In this Review, we summarize key examples from fungal plant pathogen genomics and discuss evolutionary processes in pathogenic fungi in the context of molecular evolution, population genomics and agriculture.

  2. Agrobiodiversity and genetic erosion of crop varieties and plant resources in the Central Great Caucasus

    Directory of Open Access Journals (Sweden)

    Maia Akhalkatsi

    2017-03-01

    Full Text Available Kazbegi Municipality is located in the Central Great Caucasus at an altitude between 1250 and 5047 m a.s.l. Agriculture of this area is extreme internal variability and complexity, with a multiplicity of highly localized providing the habitats and agricultural lands for much genetic erosion of crop varieties, animals, plants, fungi, and other life forms for wild plant resources. Historically, Kazbegi producers had begun cultivating the land to prepare for planting in of distribution local varieties of wheat, barley, rye, oats, etc. In the only cereals, legumes, herbs and some fruits are cultivated in alpine zone as the upper limit till the location of 2160 m a.s.l. Genetic erosion has been determined historically of aboriginal crops from sheep and cattle grazing problem and reached extreme levels from 1970s in Kazbegi Municipality and causes a problem to maintain agriculture. Plant resources remained in forests and subalpine grasslands and shrub lands. The problems of these materials are habitat degradation by disturbance in many forest types with destroyed and burned. Tree seedlings are grazing by animals and forest is not restoring naturally. Forest planting is good relation for restoration of plant wild species resources. Investigation on exchange on mountain agriculture and plant resources will now be rapidly accelerated in the vital interests of mountain communities.

  3. Convergent evolution and parallelism in plant domestication revealed by an expanding archaeological record.

    Science.gov (United States)

    Fuller, Dorian Q; Denham, Tim; Arroyo-Kalin, Manuel; Lucas, Leilani; Stevens, Chris J; Qin, Ling; Allaby, Robin G; Purugganan, Michael D

    2014-04-29

    Recent increases in archaeobotanical evidence offer insights into the processes of plant domestication and agricultural origins, which evolved in parallel in several world regions. Many different crop species underwent convergent evolution and acquired domestication syndrome traits. For a growing number of seed crop species, these traits can be quantified by proxy from archaeological evidence, providing measures of the rates of change during domestication. Among domestication traits, nonshattering cereal ears evolved more quickly in general than seed size. Nevertheless, most domestication traits show similarly slow rates of phenotypic change over several centuries to millennia, and these rates were similar across different regions of origin. Crops reproduced vegetatively, including tubers and many fruit trees, are less easily documented in terms of morphological domestication, but multiple lines of evidence outline some patterns in the development of vegecultural systems across the New World and Old World tropics. Pathways to plant domestication can also be compared in terms of the cultural and economic factors occurring at the start of the process. Whereas agricultural societies have tended to converge on higher population densities and sedentism, in some instances cultivation began among sedentary hunter-gatherers whereas more often it was initiated by mobile societies of hunter-gatherers or herder-gatherers.

  4. Crop and Substrate Tests with Single Use Rooting "Pillows" for the VEGGIE Plant Growth Hardware

    Science.gov (United States)

    Massa, Gioia; Newsham, Gerard; Caro, Janicce; Stutte, Gary; Morrow, Robert; Wheeler, Raymond

    2011-01-01

    VEGGIE is a small plant production chamber built by ORBITEC. This chamber can be collapsed for easy stowage and deployed in orbit. It is designed for gravity independent operation, and provides 0.17 square m of crop growth area with three primary subsystems: an LED light panel, extendable transparent Teflon bellows to enclose the plants, and a wicking reservoir. VEGGIE would provide the capability for astronauts to grow fresh foods for dietary supplementation. Initial planting concepts tested with the VEGGIE included direct seeding or plug placement on the reservoir surface. These options had issues of salt accumulation and eventual toxicity if the reservoir was filled with nutrient solution, and hardware reuse was limited due to sanitation. In response a rooting packet or "pillow" concept was developed: single-use bags of media containing time release fertilizer with a wicking surface contacting the VEGGIE reservoir. Pillows being tested are small electrostatic bags with a Nitex nylon mesh side, each holding 100 mL of dry media. Six pillows fit in one VEGGIE unit; however pillow size could vary depending on crop selected. Seeds can be planted directly in pillows and planted pillows can be hydrated in space as desired. Our goals were to define optimal media and crops for an ISS mission scenario. Plant tests in pillows were performed in a controlled environment chamber set to habitat-relevant conditions, and capillary reservoir analogs were utilized. Media tested within pillows included: a commercial peat-based potting mix, arcillite (calcined clay), perlite: vermiculite, and peat-based: arcillite blends. Testing included 15 types of leafy greens, snow pea, radish, and herbs. Media performance was crop dependent, but generally plants showed the greatest growth in the peat-based: arcillite mixes. Crops with the best performance in pillows were identified, and testing is underway with select leafy greens examining plant and microbial load response to repeated harvest

  5. Resistance evolution to Bt crops: predispersal mating of European corn borers.

    Directory of Open Access Journals (Sweden)

    Ambroise Dalecky

    2006-06-01

    Full Text Available Over the past decade, the high-dose refuge (HDR strategy, aimed at delaying the evolution of pest resistance to Bacillus thuringiensis (Bt toxins produced by transgenic crops, became mandatory in the United States and is being discussed for Europe. However, precopulatory dispersal and the mating rate between resident and immigrant individuals, two features influencing the efficiency of this strategy, have seldom been quantified in pests targeted by these toxins. We combined mark-recapture and biogeochemical marking over three breeding seasons to quantify these features directly in natural populations of Ostrinia nubilalis, a major lepidopteran corn pest. At the local scale, resident females mated regardless of males having dispersed beforehand or not, as assumed in the HDR strategy. Accordingly, 0-67% of resident females mating before dispersal did so with resident males, this percentage depending on the local proportion of resident males (0% to 67.2%. However, resident males rarely mated with immigrant females (which mostly arrived mated, the fraction of females mating before dispersal was variable and sometimes substantial (4.8% to 56.8%, and there was no evidence for male premating dispersal being higher. Hence, O. nubilalis probably mates at a more restricted spatial scale than previously assumed, a feature that may decrease the efficiency of the HDR strategy under certain circumstances, depending for example on crop rotation practices.

  6. PERFORMANCE OF ‘NANICÃO JANGADA’ BANANA PLANTS INTERCROPPED WITH WINTER COVER CROPS

    Directory of Open Access Journals (Sweden)

    RICARDO SFEIR DE AGUIAR

    Full Text Available ABSTRACT The use of cover crops species may be an important strategy in the pursuit of sustainability of agroecosystems, considering benefits to soil, such as improvements of physical and chemical characteristics, and weed control. The objective of this study was to evaluate the effect of winter cover crops and other soil managements on chemical soil properties, on the cycle, on the production of the first cycle and on the fruit quality of banana cv. Nanicão Jangada in Andirá – PR, Brazil. The experiment was carried out in a commercial. Planting of banana suckers from the grower area occurred in the first half of March 2011, with a spacing of 2.40 m between rows and 1.90 m between plants. The experiment was designed in randomized blocks with four replications and six plants per plot. The six treatments were: black oat (Avenastrigosa Schreb, forage turnip (Raphanus sativus L. var. oleiferus, consortium of black oat and forage turnip, chicken litter, residues of banana plants, and bare ground. The evaluations were vegetative development and life cycle of banana plants, yield and quality of fruits, soil chemical characterstics, and fresh and dry mass of green manures. The results were submitted to ANOVA (F Test, and Tukey test at 5 % probability. Black oat and black oat with forage turnip consortium were superior in biomass production. Systems of soil management had no effect on the variables, except in the periods between planting and flowering and between planting and harvest, which were shorter in the treatment of soil management with crop residues, longer in the treatment with forage turnip, and intermediate in the other treatments.

  7. Engineering Mycorrhizal Symbioses to Alter Plant Metabolism and Improve Crop Health

    Science.gov (United States)

    French, Katherine E.

    2017-01-01

    Creating sustainable bioeconomies for the 21st century relies on optimizing the use of biological resources to improve agricultural productivity and create new products. Arbuscular mycorrhizae (phylum Glomeromycota) form symbiotic relationships with over 80% of vascular plants. In return for carbon, these fungi improve plant health and tolerance to environmental stress. This symbiosis is over 400 million years old and there are currently over 200 known arbuscular mycorrhizae, with dozens of new species described annually. Metagenomic sequencing of native soil communities, from species-rich meadows to mangroves, suggests biologically diverse habitats support a variety of mycorrhizal species with potential agricultural, medical, and biotechnological applications. This review looks at the effect of mycorrhizae on plant metabolism and how we can harness this symbiosis to improve crop health. I will first describe the mechanisms that underlie this symbiosis and what physiological, metabolic, and environmental factors trigger these plant-fungal relationships. These include mycorrhizal manipulation of host genetic expression, host mitochondrial and plastid proliferation, and increased production of terpenoids and jasmonic acid by the host plant. I will then discuss the effects of mycorrhizae on plant root and foliar secondary metabolism. I subsequently outline how mycorrhizae induce three key benefits in crops: defense against pathogen and herbivore attack, drought resistance, and heavy metal tolerance. I conclude with an overview of current efforts to harness mycorrhizal diversity to improve crop health through customized inoculum. I argue future research should embrace synthetic biology to create mycorrhizal chasses with improved symbiotic abilities and potentially novel functions to improve plant health. As the effects of climate change and anthropogenic disturbance increase, the global diversity of arbuscular mycorrhizal fungi should be monitored and protected to

  8. Engineering Mycorrhizal Symbioses to Alter Plant Metabolism and Improve Crop Health

    Directory of Open Access Journals (Sweden)

    Katherine E. French

    2017-07-01

    Full Text Available Creating sustainable bioeconomies for the 21st century relies on optimizing the use of biological resources to improve agricultural productivity and create new products. Arbuscular mycorrhizae (phylum Glomeromycota form symbiotic relationships with over 80% of vascular plants. In return for carbon, these fungi improve plant health and tolerance to environmental stress. This symbiosis is over 400 million years old and there are currently over 200 known arbuscular mycorrhizae, with dozens of new species described annually. Metagenomic sequencing of native soil communities, from species-rich meadows to mangroves, suggests biologically diverse habitats support a variety of mycorrhizal species with potential agricultural, medical, and biotechnological applications. This review looks at the effect of mycorrhizae on plant metabolism and how we can harness this symbiosis to improve crop health. I will first describe the mechanisms that underlie this symbiosis and what physiological, metabolic, and environmental factors trigger these plant-fungal relationships. These include mycorrhizal manipulation of host genetic expression, host mitochondrial and plastid proliferation, and increased production of terpenoids and jasmonic acid by the host plant. I will then discuss the effects of mycorrhizae on plant root and foliar secondary metabolism. I subsequently outline how mycorrhizae induce three key benefits in crops: defense against pathogen and herbivore attack, drought resistance, and heavy metal tolerance. I conclude with an overview of current efforts to harness mycorrhizal diversity to improve crop health through customized inoculum. I argue future research should embrace synthetic biology to create mycorrhizal chasses with improved symbiotic abilities and potentially novel functions to improve plant health. As the effects of climate change and anthropogenic disturbance increase, the global diversity of arbuscular mycorrhizal fungi should be monitored

  9. Engineering Mycorrhizal Symbioses to Alter Plant Metabolism and Improve Crop Health.

    Science.gov (United States)

    French, Katherine E

    2017-01-01

    Creating sustainable bioeconomies for the 21st century relies on optimizing the use of biological resources to improve agricultural productivity and create new products. Arbuscular mycorrhizae (phylum Glomeromycota) form symbiotic relationships with over 80% of vascular plants. In return for carbon, these fungi improve plant health and tolerance to environmental stress. This symbiosis is over 400 million years old and there are currently over 200 known arbuscular mycorrhizae, with dozens of new species described annually. Metagenomic sequencing of native soil communities, from species-rich meadows to mangroves, suggests biologically diverse habitats support a variety of mycorrhizal species with potential agricultural, medical, and biotechnological applications. This review looks at the effect of mycorrhizae on plant metabolism and how we can harness this symbiosis to improve crop health. I will first describe the mechanisms that underlie this symbiosis and what physiological, metabolic, and environmental factors trigger these plant-fungal relationships. These include mycorrhizal manipulation of host genetic expression, host mitochondrial and plastid proliferation, and increased production of terpenoids and jasmonic acid by the host plant. I will then discuss the effects of mycorrhizae on plant root and foliar secondary metabolism. I subsequently outline how mycorrhizae induce three key benefits in crops: defense against pathogen and herbivore attack, drought resistance, and heavy metal tolerance. I conclude with an overview of current efforts to harness mycorrhizal diversity to improve crop health through customized inoculum. I argue future research should embrace synthetic biology to create mycorrhizal chasses with improved symbiotic abilities and potentially novel functions to improve plant health. As the effects of climate change and anthropogenic disturbance increase, the global diversity of arbuscular mycorrhizal fungi should be monitored and protected to

  10. Small RNAs in plants: Recent development and application for crop improvement

    Directory of Open Access Journals (Sweden)

    Ayushi eKamthan

    2015-04-01

    Full Text Available The phenomenon of RNA interference (RNAi which involves sequence specific gene regulation by small non-coding RNAs i.e small interfering RNA (siRNA and micro RNA (miRNA has emerged as one of most powerful approaches for crop improvement. RNAi based on siRNA is one of the widely used tools of reverse genetics which aid in revealing gene functions in many species. This technology has been extensively applied to alter the gene expression in plants with an aim to achieve desirable traits. RNAi has been used for enhancing the crop yield and productivity by manipulating the gene involved in biomass, grain yield and enhanced shelf life of fruits & vegetables. It has also been applied for developing resistance against various biotic (bacteria, fungi, viruses, nematodes, insects and abiotic stresses (drought, salinity, cold etc.. Nutritional improvements of crops have also been achieved by enriching the crops with essential amino acids, fatty acids, antioxidants and other nutrients beneficial for human health or by reducing allergens or anti-nutrients. Micro RNAs are key regulators of important plant processes like growth, development and response to various stresses. In spite of similarity in size (20-24nt, miRNA differ from siRNA in precursor structures, pathway of biogenesis, and modes of action. This review also highlights the miRNA based genetic modification technology where various miRNAs/artificial miRNAs and their targets can be utilized for improving several desirable plant traits. Micro RNA based strategies are much efficient than siRNA-based RNAi strategies due to its specificity and less undesirable off target effects. As per the FDA guidelines, small RNA based transgenics are much safer for consumption than those over expressing proteins. This review thereby summarizes the emerging advances and achievement in the field of small RNAs and its application for crop improvement.

  11. Plant Adaptation to Acid Soils: The Molecular Basis for Crop Aluminum Resistance.

    Science.gov (United States)

    Kochian, Leon V; Piñeros, Miguel A; Liu, Jiping; Magalhaes, Jurandir V

    2015-01-01

    Aluminum (Al) toxicity in acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world's potentially arable soil is acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to Al toxicity has been a focus of intense research interest in the decade since the last article on crop acid soil tolerance was published in this journal. An impressive amount of progress has been made during that time that has greatly increased our understanding of the diversity of Al resistance genes and mechanisms, how resistance gene expression is regulated and triggered by Al and Al-induced signals, and how the proteins encoded by these genes function and are regulated. This review examines the state of our understanding of the physiological, genetic, and molecular bases for crop Al tolerance, looking at the novel Al resistance genes and mechanisms that have been identified over the past ten years. Additionally, it examines how the integration of molecular and genetic analyses of crop Al resistance is starting to be exploited for the improvement of crop plants grown on acid soils via both molecular-assisted breeding and biotechnology approaches.

  12. Assessment of water sources to plant growth in rice based cropping systems by stable water isotopes

    Science.gov (United States)

    Mahindawansha, Amani; Kraft, Philipp; Racela, Heathcliff; Breuer, Lutz

    2016-04-01

    Rice is one of the most water-consuming crops in the world. Understanding water source utilization of rice will help us to improve water use efficiency (WUE) in paddy management. The objectives of our study are to evaluate the isotopic compositions of surface ponded water, soil water, irrigation water, groundwater, rain water and plant water and based on stable water isotope signatures to evaluate the contributions of various water sources to plant growth (wet rice, aerobic rice and maize) together with investigating the contribution of water from different soil horizons for plant growth in different maturity periods during wet and dry seasons. Finally we will compare the water balances and crop yields in both crops during both seasons and calculate the water use efficiencies. This will help to identify the most efficient water management systems in rice based cropping ecosystems using stable water isotopes. Soil samples are collected from 9 different depths at up to 60 cm in vegetative, reproductive and matured periods of plant growth together with stem samples. Soil and plant samples are extracted by cryogenic vacuum extraction. Root samples are collected up to 60 cm depth from 10 cm intercepts leading calculation of root length density and dry weight. Groundwater, surface water, rain water and irrigation water are sampled weekly. All water samples are analyzed for hydrogen and oxygen isotope ratios (d18O and dD) using Los Gatos Research DLT100. Rainfall records, ground water level, surface water level fluctuations and the amount of water irrigated in each field will be measured during the sampling period. The direct inference approach which is based on comparing isotopic compositions (dD and d18O) between plant stem water and soil water will be used to determine water sources taken up by plant. Multiple-source mass balance assessment can provide the estimated range of potential contributions of water from each soil depth to root water uptake of a crop. These

  13. Breeding crop plants with deep roots: their role in sustainable carbon, nutrient and water sequestration

    Science.gov (United States)

    Kell, Douglas B.

    2011-01-01

    Background The soil represents a reservoir that contains at least twice as much carbon as does the atmosphere, yet (apart from ‘root crops’) mainly just the above-ground plant biomass is harvested in agriculture, and plant photosynthesis represents the effective origin of the overwhelming bulk of soil carbon. However, present estimates of the carbon sequestration potential of soils are based more on what is happening now than what might be changed by active agricultural intervention, and tend to concentrate only on the first metre of soil depth. Scope Breeding crop plants with deeper and bushy root ecosystems could simultaneously improve both the soil structure and its steady-state carbon, water and nutrient retention, as well as sustainable plant yields. The carbon that can be sequestered in the steady state by increasing the rooting depths of crop plants and grasses from, say, 1 m to 2 m depends significantly on its lifetime(s) in different molecular forms in the soil, but calculations (http://dbkgroup.org/carbonsequestration/rootsystem.html) suggest that this breeding strategy could have a hugely beneficial effect in stabilizing atmospheric CO2. This sets an important research agenda, and the breeding of plants with improved and deep rooting habits and architectures is a goal well worth pursuing. PMID:21813565

  14. Plant Fitness Assessment for Wild Relatives of Insect Resistant Bt-Crops

    Directory of Open Access Journals (Sweden)

    D. K. Letourneau

    2012-01-01

    Full Text Available When field tests of transgenic plants are precluded by practical containment concerns, manipulative experiments can detect potential consequences of crop-wild gene flow. Using topical sprays of bacterial Bacillus thuringiensis larvicide (Bt and larval additions, we measured fitness effects of reduced herbivory on Brassica rapa (wild mustard and Raphanus sativus (wild radish. These species represent different life histories among the potential recipients of Bt transgenes from Bt cole crops in the US and Asia, for which rare spontaneous crosses are expected under high exposure. Protected wild radish and wild mustard seedlings had approximately half the herbivore damage of exposed plants and 55% lower seedling mortality, resulting in 27% greater reproductive success, 14-day longer life-spans, and 118% more seeds, on average. Seed addition experiments in microcosms and in situ indicated that wild radish was more likely to spread than wild mustard in coastal grasslands.

  15. Grain characteristics of crops grown on power plant ash and bottom slag deposit

    Energy Technology Data Exchange (ETDEWEB)

    Dzeletovic, Zeljko S.; Filipovic, Radoslav [Institute for the Application of Nuclear Energy INEP, Zemun (Yugoslavia)

    1995-05-01

    Our objective was to study mature grains of crops grown on various areas of power plant ash and bottom slag deposits. It was found that good grain quality with the application of usual agricultural techniques and intensified fertilization on various parts of ash and bottom slag deposits may be achieved with: autumn rye (Secale cereale L.), alfalfa (Medicago sativa L.), barley (Hordeum sativum Jessen) and, to a lesser extent, winter raps (Brassica napus L.)

  16. Cryopreservation techniques and their application in vegetatively propagated crop plants in Finland

    OpenAIRE

    A. NUKARI; M. UOSUKAINEN; V-M. ROKKA

    2008-01-01

    Cryopreservation protocols have been introduced as techniques for germplasm preservation of vegetatively propagated horticultural and staple food crops. In Finland, cryopreservation has been studied since 1990s, beginning with cryopreservation of forest tree breeding material and since 2004 on cryopreservation of genetic resources of horticultural plants and potato. Priority was given to cryopreservation of raspberry (Rubus ideaus L.), strawberry (Fragaria x ananassa Duch.) and potato (Solanu...

  17. Organic farming provides improved management of plant parasitic nematodes in maize and bean cropping systems

    OpenAIRE

    Atandi, Janet G.; Haukeland, Solveig; Kariuki, George M.; Coyne, Danny L.; Karanja, Edward N.; Musyoka, Martha W.; Fiaboe, Komi K.M.; Bautze, David; Adamtey, Noah

    2017-01-01

    Intensification of agriculture, combined with poor agronomic practices have increased the incidence of plant parasitic nematodes (PPN) and other soil pathogens in East Africa, which consequently affects crop productivity in small holder farms. The objective of the study was to assess the effectiveness of farming systems in management of PPN and to recommend the best practice to farmers. Therefore, two field trials were established, one infarmer fieldsandoneon-station,usingmaize (Zeamays L.), inter...

  18. Generation of transgenic plants of a potential oilseed crop Camelina sativa by Agrobacterium-mediated transformation.

    Science.gov (United States)

    Lu, Chaofu; Kang, Jinling

    2008-02-01

    Camelina sativa is an alternative oilseed crop that can be used as a potential low-cost biofuel crop or a source of health promoting omega-3 fatty acids. Currently, the fatty acid composition of camelina does not uniquely fit any particular uses, thus limit its commercial value and large-scale production. In order to improve oil quality and other agronomic characters, we have developed an efficient and simple in planta method to generate transgenic camelina plants. The method included Agrobacterium-mediated inoculation of plants at early flowering stage along with a vacuum infiltration procedure. We used a fluorescent protein (DsRed) as a visual selection marker, which allowed us to conveniently screen mature transgenic seeds from a large number of untransformed seeds. Using this method, over 1% of transgenic seeds can be obtained. Genetic analysis revealed that most of transgenic plants contain a single copy of transgene. In addition, we also demonstrated that transgenic camelina seeds produced novel hydroxy fatty acids by transforming a castor fatty acid hydroxylase. In conclusion, our results provide a rapid means to genetically improve agronomic characters of camelina, including fatty acid profiles of its seed oils. Camelina may serve as a potential industrial crop to produce novel biotechnology products.

  19. Crop Production under Drought and Heat Stress: Plant Responses and Management Options.

    Science.gov (United States)

    Fahad, Shah; Bajwa, Ali A; Nazir, Usman; Anjum, Shakeel A; Farooq, Ayesha; Zohaib, Ali; Sadia, Sehrish; Nasim, Wajid; Adkins, Steve; Saud, Shah; Ihsan, Muhammad Z; Alharby, Hesham; Wu, Chao; Wang, Depeng; Huang, Jianliang

    2017-01-01

    Abiotic stresses are one of the major constraints to crop production and food security worldwide. The situation has aggravated due to the drastic and rapid changes in global climate. Heat and drought are undoubtedly the two most important stresses having huge impact on growth and productivity of the crops. It is very important to understand the physiological, biochemical, and ecological interventions related to these stresses for better management. A wide range of plant responses to these stresses could be generalized into morphological, physiological, and biochemical responses. Interestingly, this review provides a detailed account of plant responses to heat and drought stresses with special focus on highlighting the commonalities and differences. Crop growth and yields are negatively affected by sub-optimal water supply and abnormal temperatures due to physical damages, physiological disruptions, and biochemical changes. Both these stresses have multi-lateral impacts and therefore, complex in mechanistic action. A better understanding of plant responses to these stresses has pragmatic implication for remedies and management. A comprehensive account of conventional as well as modern approaches to deal with heat and drought stresses have also been presented here. A side-by-side critical discussion on salient responses and management strategies for these two important abiotic stresses provides a unique insight into the phenomena. A holistic approach taking into account the different management options to deal with heat and drought stress simultaneously could be a win-win approach in future.

  20. Bioaccumulation of heavy metals in crop plants grown near Almeda Textile Factory, Adwa, Ethiopia.

    Science.gov (United States)

    Gitet, Hintsa; Hilawie, Masho; Muuz, Mehari; Weldegebriel, Yirgaalem; Gebremichael, Dawit; Gebremedhin, Desta

    2016-09-01

    The contents of heavy metals cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) present in water (wastewater and wetland), soils, and food crops collected from the vicinity of Almeda Textile Factory were quantified using Flame Atomic Absorption Spectrometer (FAAS) in order to assess the environmental impact of the textile factory. The contents of heavy metals determined in the wastewater were found below the recommended limit set by WHO and United States Environmental Protection Agency (US EPA) except for Cr, which was found slightly higher than WHO permissible limit. Besides, the contents of the heavy metals determined in soils were below the permissible level of FAO/WHO and Canada maximum allowable limits. Moreover, only the concentrations of Cd and Pb were found above the permissible level set by FAO/WHO in the crop plants studied. Generally, the mean concentrations of heavy metals in the plants were in the decreasing order of: Mn > Zn > Cu > Pb > Ni > Co > Cr > Cd. Nevertheless, higher bioconcentration factor (BCF) was found for Cd (0.108-1.156) followed by Zn (0.081-0.499). In conclusion, comparison of heavy metal concentrations with the permissible limits in all collected sample types i.e. water, soil, and crop plants did not show significant pollution from the factory.

  1. Quantitative Resistance to Plant Pathogens in Pyramiding Strategies for Durable Crop Protection

    Directory of Open Access Journals (Sweden)

    Marie-Laure Pilet-Nayel

    2017-10-01

    Full Text Available Quantitative resistance has gained interest in plant breeding for pathogen control in low-input cropping systems. Although quantitative resistance frequently has only a partial effect and is difficult to select, it is considered more durable than major resistance (R genes. With the exponential development of molecular markers over the past 20 years, resistance QTL have been more accurately detected and better integrated into breeding strategies for resistant varieties with increased potential for durability. This review summarizes current knowledge on the genetic inheritance, molecular basis, and durability of quantitative resistance. Based on this knowledge, we discuss how strategies that combine major R genes and QTL in crops can maintain the effectiveness of plant resistance to pathogens. Combining resistance QTL with complementary modes of action appears to be an interesting strategy for breeding effective and potentially durable resistance. Combining quantitative resistance with major R genes has proven to be a valuable approach for extending the effectiveness of major genes. In the plant genomics era, improved tools and methods are becoming available to better integrate quantitative resistance into breeding strategies. Nevertheless, optimal combinations of resistance loci will still have to be identified to preserve resistance effectiveness over time for durable crop protection.

  2. Evolution of operational parameters in a UASB wastewater plant ...

    African Journals Online (AJOL)

    The objective of this research was to establish the operational parameters of the plant and evolution of elimination of pollutants. Influent and effluent parameters used for this research, were oils, volatile fatty acidity, alkalinity, ammonium, bacteria, flow, chlorides, BOD, detergents, COD, phosphates, total nitrogen, pH, ...

  3. Soil and plant nitrogen dynamics of a tomato crop under different fertilization strategies

    DEFF Research Database (Denmark)

    Doltra, Jordi; Muñoz, P; Antón, A

    2010-01-01

    A field experiment was conducted in 2007 to investigate the effects of the N fertilizer source on the soil and plant N dynamics of a tomato crop grown in a sandy loam soil. The fertilization treatments were: mineral N-fertilization applied by fertigation (TM); organic N-fertilization (TO...... basis. Soil samples were taken before planting and at harvest from depths of up to 90 cm in order to determine moisture and N-NO3- levels. The estimated amounts of total N-NO3- available in the different treatments, including the initial content in the 0-90 cm soil layer, were 560 (TC), 570 (TO) and 610...

  4. Plant productivity and characterization of zeoponic substrates after three successive crops of radish

    Science.gov (United States)

    Gruener, J. E.; Ming, Doug; Galindo, C., Jr.; Henderson, K. E.

    2006-01-01

    The National Aeronautics and Space Administration (NASA) has developed advanced life support (ALS) systems for long duration space missions that incorporate plants to regenerate the atmosphere (CO2 to O2), recycle water (via evapotranspiration), and produce food. NASA has also developed a zeolite-based synthetic substrate consisting of clinoptilolite and synthetic apatite to support plant growth for ALS systems (Ming et al., 1995). The substrate is called zeoponics and has been designed to slowly release all plant essential elements into "soil" solution. The substrate consists of K- and NH4-exchanged clinoptilolite and a synthetic hydroxyapatite that has Mg, S, and the plant-essential micronutrients incorporated into its structure in addition to Ca and P. Plant performance in zeoponic substrates has been improved by the addition of dolomite pH buffers, nitrifying bacteria, and other calcium-bearing minerals (Henderson et al., 2000; Gruener et al., 2003). Wheat was used as the test crop for all of these studies. The objectives of this study were to expand upon the previous studies to determine the growth and nutrient uptake of radish in zeoponic substrates and to determine the nutrient availability of the zeoponic substrate after three successive radish crops.

  5. Crop Establishment Practices Are a Driver of the Plant Microbiota in Winter Oilseed Rape (Brassica napus)

    Science.gov (United States)

    Rathore, Ridhdhi; Dowling, David N.; Forristal, Patrick D.; Spink, John; Cotter, Paul D.; Bulgarelli, Davide; Germaine, Kieran J.

    2017-01-01

    Gaining a greater understanding of the plant microbiota and its interactions with its host plant heralds a new era of scientific discovery in agriculture. Different agricultural management practices influence soil microbial populations by changing a soil’s physical, chemical and biological properties. However, the impact of these practices on the microbiota associated with economically important crops such as oilseed rape, are still understudied. In this work we investigated the impact of two contrasting crop establishment practices, conventional (plow based) and conservation (strip–tillage) systems, on the microbiota inhabiting different plant microhabitats, namely rhizosphere, root and shoot, of winter oilseed rape under Irish agronomic conditions. Illumina 16S rRNA gene sequence profiling showed that the plant associated microhabitats (root and shoot), are dominated by members of the bacterial phyla Proteobacteria, Actinobacteria and Bacteroidetes. The root and shoot associated bacterial communities displayed markedly distinct profiles as a result of tillage practices. We observed a very limited ‘rhizosphere effect’ in the root zone of WOSR, i.e., there was little or no increase in bacterial community richness and abundance in the WOSR rhizosphere compared to the bulk soil. The two tillage systems investigated did not appear to lead to any major long term differences on the bulk soil or rhizosphere bacterial communities. Our data suggests that the WOSR root and shoot microbiota can be impacted by management practices and is an important mechanism that could allow us to understand how plants respond to different management practices and environments. PMID:28848510

  6. Crop Establishment Practices Are a Driver of the Plant Microbiota in Winter Oilseed Rape (Brassica napus

    Directory of Open Access Journals (Sweden)

    Ridhdhi Rathore

    2017-08-01

    Full Text Available Gaining a greater understanding of the plant microbiota and its interactions with its host plant heralds a new era of scientific discovery in agriculture. Different agricultural management practices influence soil microbial populations by changing a soil’s physical, chemical and biological properties. However, the impact of these practices on the microbiota associated with economically important crops such as oilseed rape, are still understudied. In this work we investigated the impact of two contrasting crop establishment practices, conventional (plow based and conservation (strip–tillage systems, on the microbiota inhabiting different plant microhabitats, namely rhizosphere, root and shoot, of winter oilseed rape under Irish agronomic conditions. Illumina 16S rRNA gene sequence profiling showed that the plant associated microhabitats (root and shoot, are dominated by members of the bacterial phyla Proteobacteria, Actinobacteria and Bacteroidetes. The root and shoot associated bacterial communities displayed markedly distinct profiles as a result of tillage practices. We observed a very limited ‘rhizosphere effect’ in the root zone of WOSR, i.e., there was little or no increase in bacterial community richness and abundance in the WOSR rhizosphere compared to the bulk soil. The two tillage systems investigated did not appear to lead to any major long term differences on the bulk soil or rhizosphere bacterial communities. Our data suggests that the WOSR root and shoot microbiota can be impacted by management practices and is an important mechanism that could allow us to understand how plants respond to different management practices and environments.

  7. Co-evolution of insect proteases and plant protease inhibitors.

    Science.gov (United States)

    Jongsma, Maarten A; Beekwilder, Jules

    2011-08-01

    Plants are at the basis of the food chain, but there is no such thing as a "free lunch" for herbivores. To promote reproductive success, plants evolved multi-layered defensive tactics to avoid or discourage herbivory. To the detriment of plants, herbivores, in turn, evolved intricate strategies to find, eat, and successfully digest essential plant parts to raise their own offspring. In this battle the digestive tract is the arena determining final victory or defeat as measured by growth or starvation of the herbivore. Earlier, specific molecular opponents were identified as proteases and inhibitors: digestive proteases of herbivores evolved structural motifs to occlude plant protease inhibitors, or alternatively, the insects evolved proteases capable of specifically degrading the host plant inhibitors. In response plant inhibitors evolved hyper-variable and novel protein folds to remain active against potential herbivores. At the level of protease regulation in herbivorous insects, it was shown that inhibition-insensitive digestive proteases are up-regulated when sensitive proteases are inhibited. The way this regulation operates in mammals is known as negative feedback by gut-luminal factors, so-called 'monitor peptides' that are sensitive to the concentration of active enzymes. We propose that regulation of gut enzymes by endogenous luminal factors has been an open invitation to plants to "hijack" this regulation by evolving receptor antagonists, although yet these plant factors have not been identified. In future research the question of the co-evolution of insect proteases and plant inhibitors should, therefore, be better approached from a systems level keeping in mind that evolution is fundamentally opportunistic and that the plant's fitness is primarily improved by lowering the availability of essential amino acids to an herbivore by any available mechanism.

  8. The evolution of ethylene signaling in plant chemical ecology.

    Science.gov (United States)

    Groen, Simon C; Whiteman, Noah K

    2014-07-01

    Ethylene is a key hormone in plant development, mediating plant responses to abiotic environmental stress, and interactions with attackers and mutualists. Here, we provide a synthesis of the role of ethylene in the context of plant ecology and evolution, and a prospectus for future research in this area. We focus on the regulatory function of ethylene in multi-organismal interactions. In general, plant interactions with different types of organisms lead to reduced or enhanced levels of ethylene. This in turn affects not only the plant's response to the interacting organism at hand, but also to other organisms in the community. These community-level effects become observable as enhanced or diminished relationships with future commensals, and systemic resistance or susceptibility to secondary attackers. Ongoing comparative genomic and phenotypic analyses continue to shed light on these interactions. These studies have revealed that plants and interacting organisms from separate kingdoms of life have independently evolved the ability to produce, perceive, and respond to ethylene. This signature of convergent evolution of ethylene signaling at the phenotypic level highlights the central role ethylene metabolism and signaling plays in plant interactions with microbes and animals.

  9. Evolution of Tracheids and Lignification in Early Land Plants

    Science.gov (United States)

    Boyce, C. K.; Knoll, A. H.; Cody, G. D.; Fogel, M. L.; Hazen, R. M.

    2001-05-01

    Anatomically preserved land plant fossils from the Lower Devonian Rhynie Chert contain conducting tissues that range from dark colored, elongated cells without secondary wall thickenings to tracheids similar to those of extant plants. Observed differences in conducting cell differentiation may or may not correspond to the physiological innovations of lignin biosynthesis and deposition. In order to evaluate the degree to which the morphological and physiological evolution were coupled in the tissues of early land plants, three analytical techniques were employed to study anatomically preserved fossils: electron microprobe analysis to obtain micron scale resolution of elemental abundances, isotope ratio mass spectrometry to obtain millimeter scale resolution of carbon isotopic abundances, and soft X-ray microscopy in conjunction with NMR to obtain micron scale resolution of the preservation of organic molecular functionality. Studies demonstrate that original organics are not homogenized during diagenesis and are preserved in place with sufficient spatial resolution for paleobiological investigations. Tissue-specific isotopic and organic chemistry of Rhynie Chert plants suggests that the anatomical evolution of tracheid secondary thickenings and the biochemical evolution of lignin synthesis were originally independent: the earliest vascular thickenings were unlignified and cell wall lignification may have first appeared in other tissues. Only later were the anatomical and biochemical characteristics coupled to produce true tracheids like those of all living vascular plants.

  10. Changes in gene and protein expression during tomato ripening - consequences for the safety assessment of new crop plant varieties

    NARCIS (Netherlands)

    Kok, E.J.; Lehesranta, S.J.; Dijk, van J.P.; Helsdingen, J.R.; Dijksma, W.T.P.; Hoef, van A.M.A.; Koistinen, K.M.; Karenlampi, S.O.; Kuiper, H.A.; Keijer, J.

    2008-01-01

    An important part of the comparative approach to assess the safety of new crop plant varieties is an extensive compositional analysis, including the measurement of all key nutrients and antinutrients in a specific crop. The study described here investigates the applicability of `omics' technologies,

  11. Monitoring crop health status at greenhouse scale on the basis of volatiles emitted from the plants: a review

    NARCIS (Netherlands)

    Jansen, R.M.C.; Takayama, K.; Wildt, J.; Hofstee, J.W.; Bouwmeester, H.J.; Henten, van E.J.

    2009-01-01

    This review focuses on the monitoring of crop health status at greenhouse scale, based on the measurement of volatile organic compounds (VOCs) emitted from the plants. The review includes the most important factors that affect the emission of these VOCs from greenhouse crops. Since both, stress

  12. A review of plant-pharmaceutical interactions: from uptake and effects in crop plants to phytoremediation in constructed wetlands.

    Science.gov (United States)

    Carvalho, Pedro N; Basto, M Clara P; Almeida, C Marisa R; Brix, Hans

    2014-10-01

    Pharmaceuticals are commonly found both in the aquatic and the agricultural environments as a consequence of the human activities and associated discharge of wastewater effluents to the environment. The utilization of treated effluent for crop irrigation, along with land application of manure and biosolids, accelerates the introduction of these compounds into arable lands and crops. Despite the low concentrations of pharmaceuticals usually found, the continuous introduction into the environment from different pathways makes them 'pseudo-persistent'. Several reviews have been published regarding the potential impact of veterinary and human pharmaceuticals on arable land. However, plant uptake as well as phytotoxicity data are scarcely studied. Simultaneously, phytoremediation as a tool for pharmaceutical removal from soils, sediments and water is starting to be researched, with promising results. This review gives an in-depth overview of the phytotoxicity of pharmaceuticals, their uptake and their removal by plants. The aim of the current work was to map the present knowledge concerning pharmaceutical interactions with plants in terms of uptake and the use of plant-based systems for phytoremediation purposes.

  13. Using modern plant breeding to improve the nutritional and technological qualities of oil crops

    Directory of Open Access Journals (Sweden)

    Murphy Denis J.

    2014-11-01

    Full Text Available The last few decades have seen huge advances in our understanding of plant biology and in the development of new technologies for the manipulation of crop plants. The application of relatively straightforward breeding and selection methods made possible the “Green Revolution” of the 1960s and 1970s that effectively doubled or trebled cereal production in much of the world and averted mass famine in Asia. During the 2000s, much attention has been focused on genomic approaches to plant breeding with the deployment of a new generation of technologies, such as marker-assisted selection, next-generation sequencing, transgenesis (genetic engineering or GM and automatic mutagenesis/selection (TILLING, TargetIng Local Lesions IN Genomes. These methods are now being applied to a wide range of crops and have particularly good potential for oil crop improvement in terms of both overall food and non-food yield and nutritional and technical quality of the oils. Key targets include increasing overall oil yield and stability on a per seed or per fruit basis and very high oleic acid content in seed and fruit oils for both premium edible and oleochemical applications. Other more specialised targets include oils enriched in nutritionally desirable “fish oil”-like fatty acids, especially very long chain !-3 acids such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA, or increased levels of lipidic vitamins such as carotenoids, tocopherols and tocotrienes. Progress in producing such oils in commercial crops has been good in recent years with several varieties being released or at advanced stages of development.

  14. Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

    Science.gov (United States)

    Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

    2017-06-01

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  15. Characterization and potential of plant growth promoting rhizobacteria isolated from native Andean crops.

    Science.gov (United States)

    Ogata-Gutiérrez, Katty; Chumpitaz-Segovia, Carolina; Lirio-Paredes, Jesus; Finetti-Sialer, Mariella M; Zúñiga-Dávila, Doris

    2017-10-27

    Bacteria isolated from soil and rhizosphere samples collected in Peru from Andean crops were tested in vitro and in vivo to determine their potential as plant growth promoters and their ability to induce systemic resistance to Alternaria alternata in tomato plants. The isolates were identified by sequencing their 16S ribosomal RNA gene. Test for phosphate solubilization, and indolacetic acid were also carried out, together with in vitro antagonism assays in dual cultures towards the plant pathogens Fusarium solani, A. alternata and Curvularia lunata. The three most promising isolates (Pa15, Ps155, Ps168) belonged to the genus Pseudomonas. Further assays were carried out with tomato plants to assess their plant protection effect towards A. alternata and as growth promoters. Inoculation of tomato seeds with all isolates significantly enhanced seed germination, plantlets emergence and plant development. Bacterial inoculation also reduce damage level caused by A. alternata. The expression levels of three tomato genes involved in the jasmonate (AOS), ethylene responsive (ERF-2) and pathogenesis related (PR-P2) pathways were determined in plants challenged with A. alternata, alone or with each bacterial isolate, respectively. Results showed that at 24 h after infection, in absence of the pathogen, the expression level of the tested genes was very low. The presence of A. alternata alone and in combination with bacteria increased the transcripts of all genes. Data showed a potential of best performing isolate Ps168 to sustain tomato plants nutrition and activate defense-related genes for protection by pathogenic fungi.

  16. Optimizing experimental procedures for quantitative evaluation of crop plant performance in high throughput phenotyping systems.

    Science.gov (United States)

    Junker, Astrid; Muraya, Moses M; Weigelt-Fischer, Kathleen; Arana-Ceballos, Fernando; Klukas, Christian; Melchinger, Albrecht E; Meyer, Rhonda C; Riewe, David; Altmann, Thomas

    2014-01-01

    Detailed and standardized protocols for plant cultivation in environmentally controlled conditions are an essential prerequisite to conduct reproducible experiments with precisely defined treatments. Setting up appropriate and well defined experimental procedures is thus crucial for the generation of solid evidence and indispensable for successful plant research. Non-invasive and high throughput (HT) phenotyping technologies offer the opportunity to monitor and quantify performance dynamics of several hundreds of plants at a time. Compared to small scale plant cultivations, HT systems have much higher demands, from a conceptual and a logistic point of view, on experimental design, as well as the actual plant cultivation conditions, and the image analysis and statistical methods for data evaluation. Furthermore, cultivation conditions need to be designed that elicit plant performance characteristics corresponding to those under natural conditions. This manuscript describes critical steps in the optimization of procedures for HT plant phenotyping systems. Starting with the model plant Arabidopsis, HT-compatible methods were tested, and optimized with regard to growth substrate, soil coverage, watering regime, experimental design (considering environmental inhomogeneities) in automated plant cultivation and imaging systems. As revealed by metabolite profiling, plant movement did not affect the plants' physiological status. Based on these results, procedures for maize HT cultivation and monitoring were established. Variation of maize vegetative growth in the HT phenotyping system did match well with that observed in the field. The presented results outline important issues to be considered in the design of HT phenotyping experiments for model and crop plants. It thereby provides guidelines for the setup of HT experimental procedures, which are required for the generation of reliable and reproducible data of phenotypic variation for a broad range of applications.

  17. GIS based evaluation of crop suitability for agricultural sustainability around Kolaghat thermal power plant, India.

    Science.gov (United States)

    Adak, Subhas; Adhikari, Kalyan; Brahmachari, Koushik

    2016-09-01

    Fly ash exhaust from Kolaghat thermal power plant, West Bengal, India,?? affects the areas within the radius of 3 - 4 km. Land information system indicated that surface texture within 4 km was silty loam and clay content increased with increase of distance. Soil pH was alkaline (7.58-8.01) in affected circles, whereas soil was acidic (5.95-6.41) in rest of block. Organic carbon (OC) is roving from 0.36 to 0.64% in the nearer circles which is lesser from others. The present Crop suitability analysis revealed that 96.98 % area was suitable (S1) for maize, sesame, jute, whereas these were cultivated in less than 1% of land. Flowers are the best suitable (S1) in 88.9 % but it was grown in 6.02 % area.? The present rice area within 4 km of KTPP is showing moderately suitable (S2) and S1 for the rest. Wheat is moderately suitable (S2) in the almost all the circles.? Cultivation of vegetable crops is limited in the affected circles while the highly suitable (S1) comprises 67.49 % for the remaining areas though it covered only 6.01 % of the block.? This evaluation precisely improves more than 300% from the earlier cropping intensity of 177.95 %. Suitability based land use allocation serves as stepping stone to promote agricultural sustainability. Geographic information system (GIS) model has been developed to assess site specific crop suitability for sustainable agricultural planning.

  18. Induced plant resistance as a pest management tactic on piercing sucking insects of sesame crop

    Directory of Open Access Journals (Sweden)

    M. F. Mahmoud

    2013-09-01

    Full Text Available Sesame, Sesamum indicum L. is the most oil seed crop of the world and also a major oil seed crop of Egypt. One of the major constraints in its production the damage caused by insect pests, particularly sucking insects which suck the cell sap from leaves, flowers and capsules. Impact of three levels of potassin-F, salicylic acid and combination between them on reduction infestation of Stink bug Nezara viridula L., Mirid bug Creontiades sp., Green peach aphid Myzus persicae (Sulzer, Leafhopper Empoasca lybica de Berg and Whitefly Bemisia tabaci (Gennadius of sesame crop cultivar Shandawil 3 was carried out during 2010-2011 crop season at Experimental farm, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt. Also, the impacts of potassin-F and salicylic acid on yield production of sesame were studied. Results indicated that percent of reduction of infestation by N. viridula, M. persicae, Creontiades sp., E. lybicae, B. tabaci and phyllody disease were significantly higher at Level 2 (Potassin-F= 2.5 cm/l, Salicylic acid= 0.001 M and Potassin + Salicylic= 2.5 cm/l + 0.001 M and consequently higher seed yield per plant were obtained.

  19. PLANTING TIMES AND SPACING OF CARROT CROPS IN THE SÃO FRANCISCO VALLEY, PERNAMBUCO STATE, BRAZIL

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    GERALDO MILANEZ DE RESENDE

    2016-01-01

    Full Text Available Climate variations over the year and plant density tend to strongly affect the agronomic performance of carrot crops. Thus, the objective of this work was to evaluate the performance of the cultivar Brasilia in crops under mild (winter and high (summer temperatures. An experiment was conducted from May 2011 to February 2012, using a randomized block design and treatments arranged in split plot, with three replications. The plots consisted of planting seasons (winter and summer and the subplots of plant spacing (4, 6, 8 and 10 cm. The height of plants presented a linear decrease, from 53.4 to 51.0 cm, with an increase in spacing in summer planting, while in winter the greatest height (50.7 cm was obtained with spacing of 8.0 cm between plants. The lowest commercial yields were found in summer crops and with the widest spacing between plants. The smallest spacing between plants (4 cm had yields of 45.9 Mg ha-1 in summer and of 63.1 Mg ha-1 in winter crops. The winter planting had higher fresh root weight (89.9 g root-1 compared to the summer (81.4 g root-1, reaching higher weight with increasing plant spacing. Higher yields are achieved with plant spacing of 4 cm during winter. The carrot can be grown throughout the year in the Submiddle of the São Francisco Valley.

  20. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae in Four Crop Plants.

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    John W Gordy

    Full Text Available Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA, benzothiadiazole (BTH, gibberellic acid (GA, harpin, and jasmonic acid (JA are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith (FAW (Lepidoptera: Noctuidae larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

  1. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants.

    Science.gov (United States)

    Gordy, John W; Leonard, B Rogers; Blouin, David; Davis, Jeffrey A; Stout, Michael J

    2015-01-01

    Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

  2. Crop residue harvest for bioenergy production and its implications on soil functioning and plant growth: A review

    Directory of Open Access Journals (Sweden)

    Maurício Roberto Cherubin

    Full Text Available ABSTRACT: The use of crop residues as a bioenergy feedstock is considered a potential strategy to mitigate greenhouse gas (GHG emissions. However, indiscriminate harvesting of crop residues can induce deleterious effects on soil functioning, plant growth and other ecosystem services. Here, we have summarized the information available in the literature to identify and discuss the main trade-offs and synergisms involved in crop residue management for bioenergy production. The data consistently showed that crop residue harvest and the consequent lower input of organic matter into the soil led to C storage depletions over time, reducing cycling, supply and availability of soil nutrients, directly affecting the soil biota. Although the biota regulates key functions in the soil, crop residue can also cause proliferation of some important agricultural pests. In addition, crop residues act as physical barriers that protect the soil against raindrop impact and temperature variations. Therefore, intensive crop residue harvest can cause soil structure degradation, leading to soil compaction and increased risks of erosion. With regard to GHG emissions, there is no consensus about the potential impact of management of crop residue harvest. In general, residue harvest decreases CO2 and N2O emissions from the decomposition process, but it has no significant effect on CH4 emissions. Plant growth responses to soil and microclimate changes due to crop residue harvest are site and crop specific. Adoption of the best management practices can mitigate the adverse impacts of crop residue harvest. Longterm experiments within strategic production regions are essential to understand and monitor the impact of integrated agricultural systems and propose customized solutions for sustainable crop residue management in each region or landscape. Furthermore, private and public investments/cooperations are necessary for a better understanding of the potential environmental

  3. Genetic basis and detection of unintended effects in genetically modified crop plants.

    Science.gov (United States)

    Ladics, Gregory S; Bartholomaeus, Andrew; Bregitzer, Phil; Doerrer, Nancy G; Gray, Alan; Holzhauser, Thomas; Jordan, Mark; Keese, Paul; Kok, Esther; Macdonald, Phil; Parrott, Wayne; Privalle, Laura; Raybould, Alan; Rhee, Seung Yon; Rice, Elena; Romeis, Jörg; Vaughn, Justin; Wal, Jean-Michel; Glenn, Kevin

    2015-08-01

    In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled "Genetic Basis of Unintended Effects in Modified Plants" was held in Ottawa, Canada, bringing together over 75 scientists from academia, government, and the agro-biotech industry. The objectives of the meeting were to explore current knowledge and identify areas requiring further study on unintended effects in plants and to discuss how this information can inform and improve genetically modified (GM) crop risk assessments. The meeting featured presentations on the molecular basis of plant genome variability in general, unintended changes at the molecular and phenotypic levels, and the development and use of hypothesis-driven evaluations of unintended effects in assessing conventional and GM crops. The development and role of emerging "omics" technologies in the assessment of unintended effects was also discussed. Several themes recurred in a number of talks; for example, a common observation was that no system for genetic modification, including conventional methods of plant breeding, is without unintended effects. Another common observation was that "unintended" does not necessarily mean "harmful". This paper summarizes key points from the information presented at the meeting to provide readers with current viewpoints on these topics.

  4. Energy efficiency and energy homeostasis as genetic and epigenetic components of plant performance and crop productivity.

    Science.gov (United States)

    De Block, Marc; Van Lijsebettens, Mieke

    2011-06-01

    The importance of energy metabolism in plant performance and plant productivity is conceptually well recognized. In the eighties, several independent studies in Lolium perenne (ryegrass), Zea mays (maize), and Festuca arundinacea (tall fescue) correlated low respiration rates with high yields. Similar reports in the nineties largely confirmed this correlation in Solanum lycopersicum (tomato) and Cucumis sativus (cucumber). However, selection for reduced respiration does not always result in high-yielding cultivars. Indeed, the ratio between energy content and respiration, defined here as energy efficiency, rather than respiration on its own, has a major impact on the yield potential of a crop. Besides energy efficiency, energy homeostasis, representing the balance between energy production and consumption in a changing environment, also contributes to an enhanced plant performance and this happens mainly through an increased stress tolerance. Although a few single gene approaches look promising, probably whole interacting networks have to be modulated, as is done by classical breeding, to improve the energy status of plants. Recent developments show that both energy efficiency and energy homeostasis have an epigenetic component that can be directed and stabilized by artificial selection (i.e. selective breeding). This novel approach offers new opportunities to improve yield potential and stress tolerance in a wide variety of crops. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Plant Water Stress Affects Interactions Between an Invasive and a Naturalized Aphid Species on Cereal Crops.

    Science.gov (United States)

    Foote, N E; Davis, T S; Crowder, D W; Bosque-Pérez, N A; Eigenbrode, S D

    2017-06-01

    In cereal cropping systems of the Pacific Northwestern United States (PNW), climate change is projected to increase the frequency of drought during summer months, which could increase water stress for crop plants. Yet, it remains uncertain how interactions between herbivore species are affected by drought stress. Here, interactions between two cereal aphids present in PNW cereal systems, Metopolophium festucae (Theobald) subsp. cerealium (a newly invasive species) and Rhopalosiphum padi L. (a naturalized species), were tested relative to wheat water stress. When aphids were confined in leaf cages on wheat, asymmetrical facilitation occurred; per capita fecundity of R. padi was increased by 46% when M. festucae cerealium was also present, compared to when only R. padi was present. Imposed water stress did not influence this interaction. When aphids were confined on whole wheat plants, asymmetrical competition occurred; cocolonization inhibited M. festucae cerealium population growth but did not affect R. padi population growth. Under conditions of plant water stress, however, the inhibitory effect of R. padi on M. festucae cerealium was not observed. We conclude that beneficial effects of cocolonization on R. padi are due to a localized plant response to M. festucae cerealium feeding, and that cocolonization of plants is likely to suppress M. festucae cerealium populations under ample water conditions, but not when plants are water stressed. This suggests that plant responses to water stress alter the outcome of competition between herbivore species, with implications for the structure of pest communities on wheat during periods of drought. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  6. Optimizing experimental procedures for quantitative evaluation of crop plant performance in high throughput phenotyping systems

    Directory of Open Access Journals (Sweden)

    Astrid eJunker

    2015-01-01

    Full Text Available Detailed and standardized protocols for plant cultivation in environmentally controlled conditions are an essential prerequisite to conduct reproducible experiments with precisely defined treatments. Setting up appropriate and well defined experimental procedures is thus crucial for the generation of solid evidence and is thus indispensable for successful plant research. Non-invasive and high throughput (HT phenotyping technologies offer the opportunity to monitor and quantify performance dynamics of several hundreds of plants at a time. Compared to small scale plant cultivations, HT systems have much higher demands, from a conceptual and a logistic point of view, on experimental design, as well as the actual plant cultivation conditions, and the image analysis and statistical methods for data evaluation. Furthermore, cultivation conditions need to be designed that elicit plant performance characteristics corresponding to those under natural conditions. This manuscript describes critical steps in the optimization of procedures for HT plant phenotyping systems. Starting with the model plant Arabidopsis, HT-compatible methods were tested, and optimized with regard to growth substrate, soil coverage, watering regime, experimental design (considering environmental inhomogeneities in automated plant cultivation and imaging systems. As revealed by metabolite profiling, plant movement did not affect the plants’ physiological status. Based on these results, procedures for maize HT cultivation and monitoring were established. Variation of maize vegetative growth in the HT phenotyping system did match well with that observed in the field. The presented results outline important issues to be considered in the design of HT phenotyping experiments for model and crop plants. It thereby provides guidelines for the setup of HT experimental procedures, which are required for the generation of reliable and reproducible data of phenotypic variation for a broad

  7. Neonicotinoid insecticides alter induced defenses and increase susceptibility to spider mites in distantly related crop plants.

    Directory of Open Access Journals (Sweden)

    Adrianna Szczepaniec

    Full Text Available Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae, in multiple, distantly related crop plants.Using cotton (Gossypium hirsutum, corn (Zea mays and tomato (Solanum lycopersicum plants, we show that transcription of phenylalanine ammonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment.Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated.

  8. Neonicotinoid insecticides alter induced defenses and increase susceptibility to spider mites in distantly related crop plants.

    Science.gov (United States)

    Szczepaniec, Adrianna; Raupp, Michael J; Parker, Roy D; Kerns, David; Eubanks, Micky D

    2013-01-01

    Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine ammonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment. Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated.

  9. Principle and application of plant mutagenesis in crop improvement: a review

    Directory of Open Access Journals (Sweden)

    Yusuff Oladosu

    2016-01-01

    Full Text Available The first step in plant breeding is to identify suitable genotypes containing the desired genes among existing varieties, or to create one if it is not found in nature. In nature, variation occurs mainly as a result of mutations and without it, plant breeding would be impossible. In this context, the major aim in mutation-based breeding is to develop and improve well-adapted plant varieties by modifying one or two major traits to increase their productivity or quality. Both physical and chemical mutagenesis is used in inducing mutations in seeds and other planting materials. Then, selection for agronomic traits is done in the first generation, whereby most mutant lines may be discarded. The agronomic traits are confirmed in the second and third generations through evident phenotypic stability, while other evaluations are carried out in the subsequent generations. Finally, only the mutant lines with desirable traits are selected as a new variety or as a parent line for cross breeding. New varieties derived by induced mutatgenesis are used worldwide: rice in Vietnam, Thailand, China and the United States; durum wheat in Italy and Bulgaria; barley in Peru and European nations; soybean in Vietnam and China; wheat in China; as well as leguminous food crops in Pakistan and India. This paper integrates available data about the impact of mutation breeding-derived crop varieties around the world and highlights the potential of mutation breeding as a flexible and practicable approach applicable to any crop provided that appropriate objectives and selection methods are used.

  10. Mapping Crop Planting Quality in Sugarcane from UAV Imagery: A Pilot Study in Nicaragua

    Directory of Open Access Journals (Sweden)

    Inti Luna

    2016-06-01

    Full Text Available Sugarcane is an important economic resource for many tropical countries and optimizing plantations is a serious concern with economic and environmental benefits. One of the best ways to optimize the use of resources in those plantations is to minimize the occurrence of gaps. Typically, gaps open in the crop canopy because of damaged rhizomes, unsuccessful sprouting or death young stalks. In order to avoid severe yield decrease, farmers need to fill the gaps with new plants. Mapping gap density is therefore critical to evaluate crop planting quality and guide replanting. Current field practices of linear gap evaluation are very labor intensive and cannot be performed with sufficient intensity as to provide detailed spatial information for mapping, which makes replanting difficult to perform. Others have used sensors carried by land vehicles to detect gaps, but these are complex and require circulating over the entire area. We present a method based on processing digital mosaics of conventional images acquired from a small Unmanned Aerial Vehicle  (UAV that produced a map of gaps at 23.5 cm resolution in a study area of 8.7 ha with 92.9% overall accuracy. Linear Gap percentage estimated from this map for a grid with cells of 10 m × 10 m linearly correlates with photo-interpreted linear gap percentage with a coefficient of determination (R2= 0.9; a root mean square error (RMSE = 5.04; and probability (p << 0.01. Crop Planting Quality levels calculated from image-derived gaps agree with those calculated from a photo-interpreted version of currently used field methods (Spearman coefficient = 0.92. These results clearly demonstrate the effectiveness of processing mosaics of Unmanned Aerial System (UAS images for mapping gap density and, together with previous studies using satellite and hand-held spectroradiometry, suggests the extension towards multi-spectral imagery to add insight on plant condition.

  11. The compact Selaginella genome identifies changes in gene content associated with the evolution of vascular plants

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.; Banks, Jo Ann; Nishiyama, Tomoaki; Hasebe, Mitsuyasu; Bowman, John L.; Gribskov, Michael; dePamphilis, Claude; Albert, Victor A.; Aono, Naoki; Aoyama, Tsuyoshi; Ambrose, Barbara A.; Ashton, Neil W.; Axtell, Michael J.; Barker, Elizabeth; Barker, Michael S.; Bennetzen, Jeffrey L.; Bonawitz, Nicholas D.; Chapple, Clint; Cheng, Chaoyang; Correa, Luiz Gustavo Guedes; Dacre, Michael; DeBarry, Jeremy; Dreyer, Ingo; Elias, Marek; Engstrom, Eric M.; Estelle, Mark; Feng, Liang; Finet, Cedric; Floyd, Sandra K.; Frommer, Wolf B.; Fujita, Tomomichi; Gramzow, Lydia; Gutensohn, Michael; Harholt, Jesper; Hattori, Mitsuru; Heyl, Alexander; Hirai, Tadayoshi; Hiwatashi, Yuji; Ishikawa, Masaki; Iwata, Mineko; Karol, Kenneth G.; Koehler, Barbara; Kolukisaoglu, Uener; Kubo, Minoru; Kurata, Tetsuya; Lalonde, Sylvie; Li, Kejie; Li, Ying; Litt, Amy; Lyons, Eric; Manning, Gerard; Maruyama, Takeshi; Michael, Todd P.; Mikami, Koji; Miyazaki, Saori; Morinaga, Shin-ichi; Murata, Takashi; Mueller-Roeber, Bernd; Nelson, David R.; Obara, Mari; Oguri, Yasuko; Olmstead, Richard G.; Onodera, Naoko; Petersen, Bent Larsen; Pils, Birgit; Prigge, Michael; Rensing, Stefan A.; Riano-Pachon, Diego Mauricio; Roberts, Alison W.; Sato, Yoshikatsu; Scheller, Henrik Vibe; Schulz, Burkhard; Schulz, Christian; Shakirov, Eugene V.; Shibagaki, Nakako; Shinohara, Naoki; Shippen, Dorothy E.; Sorensen, Iben; Sotooka, Ryo; Sugimoto, Nagisa; Sugita, Mamoru; Sumikawa, Naomi; Tanurdzic, Milos; Theilsen, Gunter; Ulvskov, Peter; Wakazuki, Sachiko; Weng, Jing-Ke; Willats, William W.G.T.; Wipf, Daniel; Wolf, Paul G.; Yang, Lixing; Zimmer, Andreas D.; Zhu, Qihui; Mitros, Therese; Hellsten, Uffe; Loque, Dominique; Otillar, Robert; Salamov, Asaf; Schmutz, Jeremy; Shapiro, Harris; Lindquist, Erika; Lucas, Susan; Rokhsar, Daniel

    2011-04-28

    We report the genome sequence of the nonseed vascular plant, Selaginella moellendorffii, and by comparative genomics identify genes that likely played important roles in the early evolution of vascular plants and their subsequent evolution

  12. Genetic engineering of cytokinin metabolism: prospective way to improve agricultural traits of crop plants.

    Science.gov (United States)

    Zalabák, David; Pospíšilová, Hana; Šmehilová, Mária; Mrízová, Katarína; Frébort, Ivo; Galuszka, Petr

    2013-01-01

    Cytokinins (CKs) are ubiquitous phytohormones that participate in development, morphogenesis and many physiological processes throughout plant kingdom. In higher plants, mutants and transgenic cells and tissues with altered activity of CK metabolic enzymes or perception machinery, have highlighted their crucial involvement in different agriculturally important traits, such as productivity, increased tolerance to various stresses and overall plant morphology. Furthermore, recent precise metabolomic analyses have elucidated the specific occurrence and distinct functions of different CK types in various plant species. Thus, smooth manipulation of active CK levels in a spatial and temporal way could be a very potent tool for plant biotechnology in the future. This review summarises recent advances in cytokinin research ranging from transgenic alteration of CK biosynthetic, degradation and glucosylation activities and CK perception to detailed elucidation of molecular processes, in which CKs work as a trigger in model plants. The first attempts to improve the quality of crop plants, focused on cereals are discussed, together with proposed mechanism of action of the responses involved. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Plastid genomics in horticultural species: Importance and applications for plant diversity, evolution and biotechnology

    Directory of Open Access Journals (Sweden)

    Marcelo eRogalski

    2015-07-01

    Full Text Available During the evolution of the eukaryotic cell, plastids and mitochondria arose from an endosymbiotic process, which determined the presence of three genetic compartments into the incipient plant cell. After that, these three genetic materials from host and symbiont suffered several rearrangements, bringing on a complex interaction between nuclear and organellar gene products. Nowadays, plastids harbor a small genome with ~130 genes in a 100-220 kb sequence in higher plants. Plastid genes are mostly highly conserved between plant species, being useful for phylogenetic analysis in higher taxa. However, intergenic spacers have a relatively higher mutation rate and are important markers to study genetic diversity and divergence within natural plant populations. The predominant uniparental inheritance of plastids is like a highly desirable feature for phylogeny studies. Moreover, the gene content and genome rearrangements are efficient tools to capture and understand evolutionary events between different plant species. Currently, genetic engineering of the plastid genome (plastome offers a number of attractive advantages as high-level of foreign protein expression, marker-gene excision, gene expression in operon and transgene containment because of maternal inheritance of plastid genome in most crops. Therefore, plastid genome can be used for adding new characteristics related to synthesis of metabolic compounds, biopharmaceutical and tolerance to biotic and abiotic stresses. Here, we describe the importance and applications of plastid genome as tools for genetic and evolutionary studies, and plastid transformation focusing on increasing the performance of horticultural species in the field.

  14. The evolution of the coal handling plant operations

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, S. [British Steel, Scunthorpe (United Kingdom). Dawes Lane Coke Ovens

    1997-12-31

    The Dawes Lane Coal Handling Plant was built during the mid 1970s, to supply blended and crushed coal to the various coke ovens on Scunthorpe Works in Yorkshire, UK. The plant was equipped with a wagon unloading station, two stacker reclaimers, crushing facilities, appropriate silo capacity and associated stockyard and conveying systems. Currently the plant is processing around 2.5 million tonnes of coal per annum. The paper describes the evolution of the plant, details some of the changes made over the years to improve efficiency, and reports some of the more unusual events that have occurred. The paper was presented to the Midland Section of the Coke Oven Managers` Association in March 1996. 7 photos.

  15. Effects of crop residue on soil and plant water evaporation in a dryland cotton system

    Science.gov (United States)

    Lascano, R. J.; Baumhardt, R. L.

    1996-03-01

    Dryland agricultural cropping systems emphasize sustaining crop yields with limited use of fertilizer while conserving both rain water and the soil. Conservation of these resources may be achieved with management systems that retain residues at the soil surface simultaneously modifying both its energy and water balance. A conservation practice used with cotton grown on erodible soils of the Texas High Plains is to plant cotton into chemically terminated wheat residues. In this study, the partitioning of daily and seasonal evapotranspiration ( E t) into soil and plant water evaporation was compared for a conventional and a terminated-wheat cotton crop using the numerical model ENWATBAL. The model was configured to account for the effects of residue on the radiative fluxes and by introducing an additional resistance to latent and sensible heat fluxes derived from measurements of wind speed and vapor conductance from a soil covered with wheat-stubble. Our results showed that seasonal E t was similar in both systems and that cumulative soil water evaporation was 50% of E t in conventional cotton and 31% of E t in the wheat-stubble cotton. Calculated values of E t were in agreement with measured values. The main benefit of the wheat residues was to suppress soil water evaporation by intercepting irradiance early in the growing season when the crop leaf area index (LAI) was low. In semiarid regions LAI of dryland cotton seldom exceeds 2 and residues can improve water conservation. Measured soil temperatures showed that early in the season residues reduced temperature at 0.1 m depth by as much as 5°C and that differences between systems diminished with depth and over time. Residues increased lint yield per unit of E t while not modifying seasonal E t and reducing cumulative soil water evaporation.

  16. Evolution of allosteric regulation in chorismate mutases from early plants

    Energy Technology Data Exchange (ETDEWEB)

    Kroll, Kourtney; Holland, Cynthia K.; Starks, Courtney M.; Jez, Joseph M.

    2017-09-28

    Plants, fungi, and bacteria synthesize the aromatic amino acids: l-phenylalanine, l-tyrosine, and l-tryptophan. Chorismate mutase catalyzes the branch point reaction of phenylalanine and tyrosine biosynthesis to generate prephenate. In Arabidopsis thaliana, there are two plastid-localized chorismate mutases that are allosterically regulated (AtCM1 and AtCM3) and one cytosolic isoform (AtCM2) that is unregulated. Previous analysis of plant chorismate mutases suggested that the enzymes from early plants (i.e. bryophytes/moss, lycophytes, and basal angiosperms) formed a clade distinct from the isoforms found in flowering plants; however, no biochemical information on these enzymes is available. To understand the evolution of allosteric regulation in plant chorismate mutases, we analyzed a basal lineage of plant enzymes homologous to AtCM1 based on sequence similarity. The chorismate mutases from the moss/bryophyte Physcomitrella patens (PpCM1 and PpCM2), the lycophyte Selaginella moellendorffii (SmCM), and the basal angiosperm Amborella trichopoda (AmtCM1 and AmtCM2) were characterized biochemically. Tryptophan was a positive effector for each of the five enzymes examined. Histidine was a weak positive effector for PpCM1 and AmtCM1. Neither tyrosine nor phenylalanine altered the activity of SmCM; however, tyrosine was a negative regulator of the other four enzymes. Phenylalanine down-regulates both moss enzymes and AmtCM2. The 2.0 Å X-ray crystal structure of PpCM1 in complex with the tryptophan identified the allosteric effector site and reveals structural differences between the R- (more active) and T-state (less active) forms of plant chorismate mutases. Molecular insight into the basal plant chorismate mutases guides our understanding of the evolution of allosteric regulation in these enzymes.

  17. The evolution of land plants: a perspective from horizontal gene transfer

    Directory of Open Access Journals (Sweden)

    Qia Wang

    2014-12-01

    Full Text Available Recent studies suggest that horizontal gene transfer (HGT played a significant role in the evolution of eukaryotic lineages. We here review the mechanisms of HGT in plants and the importance of HGT in land plant evolution. In particular, we discuss the role of HGT in plant colonization of land, phototropic response, C4 photosynthesis, and mitochondrial genome evolution.

  18. The first crop plant genetically engineered to release an insect pheromone for defence.

    Science.gov (United States)

    Bruce, Toby J A; Aradottir, Gudbjorg I; Smart, Lesley E; Martin, Janet L; Caulfield, John C; Doherty, Angela; Sparks, Caroline A; Woodcock, Christine M; Birkett, Michael A; Napier, Johnathan A; Jones, Huw D; Pickett, John A

    2015-06-25

    Insect pheromones offer potential for managing pests of crop plants. Volatility and instability are problems for deployment in agriculture but could be solved by expressing genes for the biosynthesis of pheromones in the crop plants. This has now been achieved by genetically engineering a hexaploid variety of wheat to release (E)-β-farnesene (Eβf), the alarm pheromone for many pest aphids, using a synthetic gene based on a sequence from peppermint with a plastid targeting amino acid sequence, with or without a gene for biosynthesis of the precursor farnesyl diphosphate. Pure Eβf was produced in stably transformed wheat lines with no other detectable phenotype but requiring targeting of the gene produced to the plastid. In laboratory behavioural assays, three species of cereal aphids were repelled and foraging was increased for a parasitic natural enemy. Although these studies show considerable potential for aphid control, field trials employing the single and double constructs showed no reduction in aphids or increase in parasitism. Insect numbers were low and climatic conditions erratic suggesting the need for further trials or a closer imitation, in the plant, of alarm pheromone release.

  19. Brassinosteroids play a critical role in the regulation of pesticide metabolism in crop plants

    Science.gov (United States)

    Zhou, Yanhong; Xia, Xiaojian; Yu, Gaobo; Wang, Jitao; Wu, Jingxue; Wang, Mengmeng; Yang, Youxin; Shi, Kai; Yu, Yunlong; Chen, Zhixiang; Gan, Jay; Yu, Jingquan

    2015-01-01

    Pesticide residues in agricultural produce pose a threat to human health worldwide. Although the detoxification mechanisms for xenobiotics have been extensively studied in mammalian cells, information about the regulation network in plants remains elusive. Here we show that brassinosteroids (BRs), a class of natural plant hormones, decreased residues of common organophosphorus, organochlorine and carbamate pesticides by 30–70% on tomato, rice, tea, broccoli, cucumber, strawberry, and other plants when treated externally. Genome-wide microarray analysis showed that fungicide chlorothalonil (CHT) and BR co-upregulated 301 genes, including a set of detoxifying genes encoding cytochrome P450, oxidoreductase, hydrolase and transferase in tomato plants. The level of BRs was closely related to the respiratory burst oxidase 1 (RBOH1)-encoded NADPH oxides-dependent H2O2 production, glutathione biosynthesis and the redox homeostasis, and the activity of glutathione S-transferase (GST). Gene silencing treatments showed that BRs decreased pesticide residues in plants likely by promoting their metabolism through a signaling pathway involving BRs-induced H2O2 production and cellular redox change. Our study provided a novel approach for minimizing pesticide residues in crops by exploiting plants' own detoxification mechanisms. PMID:25761674

  20. Cryopreservation techniques and their application in vegetatively propagated crop plants in Finland

    Directory of Open Access Journals (Sweden)

    A. NUKARI

    2008-12-01

    Full Text Available Cryopreservation protocols have been introduced as techniques for germplasm preservation of vegetatively propagated horticultural and staple food crops. In Finland, cryopreservation has been studied since 1990’s, beginning with cryopreservation of forest tree breeding material and since 2004 on cryopreservation of genetic resources of horticultural plants and potato. Priority was given to cryopreservation of raspberry (Rubus ideaus L., strawberry (Fragaria x ananassa Duch. and potato (Solanum tuberosum L. and the possibility to use cryotherapy in eradication of raspberry bushy dwarf virus (RBDV from in vitro cultures were studied on raspberry. Modified droplet vitrification cryopreservation protocols were designed for raspberry and strawberry and cryotherapy combined with thermotherapy was proven to be a successful application to eliminate RBDV from infected raspberries. Cryotherapy method can be applied for a large scale elimination of viruses from plant germplasm and from candidate nuclear stock in a certified plant production scheme. Routine use of cryotechniques in germplasm preservation of vegetatively propagated horticultural plants was started. Besides for long term germplasm preservation, cryopreservation techniques can be applied also for maintenance of mother stocks in certified plant production schemes and in commercial plant production. Cryopreservation of potato shoot tips needs additional detailed research to obtain sufficient recovery and regrowth rates.;

  1. Reconciling functions and evolution of isoprene emission in higher plants.

    Science.gov (United States)

    Loreto, Francesco; Fineschi, Silvia

    2015-04-01

    Compilation and analysis of existing inventories reveal that isoprene is emitted by c. 20% of the perennial vegetation of tropical and temperate regions of the world. Isoprene emitters are found across different plant families without any clear phylogenetic thread. However, by critically appraising information in inventories, several ecological patterns of isoprene emission can be highlighted, including absence of emission from C4 and annual plants, and widespread emission from perennial and deciduous plants of temperate environments. Based on this analysis, and on available information on biochemistry, ecology and functional roles of isoprene, it is suggested that isoprene may not have evolved to help plants face heavy or prolonged stresses, but rather assists C3 plants to run efficient photosynthesis and to overcome transient and mild stresses, especially during periods of active plant growth in warm seasons. When the stress status persists, or when evergreen leaves cope with multiple and repeated stresses, isoprene biosynthesis is replaced by the synthesis of less volatile secondary compounds, in part produced by the same biochemical pathway, thus indicating causal determinism in the evolution of isoprene-emitting plants in response to the environment. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  2. The Relation between Sludge Compost Application and Dense Planting Effect on the Rice Cropping

    OpenAIRE

    奥村, 俊勝

    2004-01-01

    [Synopsis] In the field experiment, the relation between sludge compost application and dense planting effects was investigated on the rice cropping. When 1000g/m2 of the compost application was added, it increase about 60g/m2 of rice grain yield. This in turn will suggest that the compost applicationincrease gave rise to produce rice yield increase. The grain yield increase was occurred significantly from density effect on the compost application. It was large effect on yield that tiller num...

  3. Alelopatia de cultivos de cobertura vegetal sobre plantas infestantes = Allelopathy of cover crop on weed plants

    Directory of Open Access Journals (Sweden)

    Luciene Kazue Tokura

    2006-07-01

    Full Text Available O presente trabalho avaliou o potencial alelopático de cultivos de cobertura vegetal de trigo, aveia preta, milheto, nabo forrageiro e colza sobre o desenvolvimento de plantas infestantes e verificou qual das coberturas vegetais exerce maior controle sobre as mesmas. Os cultivos de cobertura vegetal foram implantados sob preparo convencional (uma aração e uma gradagem no Núcleo Experimental de Engenharia Agrícola (NEEA, da Universidade Estadual do Oeste do Paraná (Unioeste, Cascavel, Estado do Paraná. Mensalmente, realizou-se o acompanhamento e identificação das plantas infestantes emersas nas áreas de cobertura vegetal no período de agosto de 2000 a agosto de 2001. Os resultados obtidos permitiram concluir que das espécies encontradas, o capim marmelada foi o que apresentou maior potencial alelopático e a erva-de-santa-maria o menor. As coberturasvegetais que apresentaram melhor controle do total de plantas infestantes presentes na área experimental, incluindo àquelas com reconhecido potencial alelopático, foram aveia preta, colza, nabo forrageiro e milheto.This work evaluated the cover crop allelopathic potential of wheat, black oat, pearl millet, turnip and rape on the development of weed plants. It also verified which cover crop has larger control on the weed plants. The cover crop was implanted under conventional tillage (one disk plowing plus one disk harrowing in the Experimental Nucleus of Agricultural Engineering (NEEA, of the State University of the West of Paraná (Unioeste, Cascavel, Paraná State. Monthly (from August 2000 to August 2001, weed plants identification in the cover crop area was made. Results showed that from the found species, the alexander grass was the one that presented larger allelopathic potential, and, the mexican-tea was the one that presented smaller control. The vegetable coverings that presented larger control of the total of weed plants in the experimental area, including those with

  4. Biological determinants of plant and crop productivity of flax (Linum usitatissimum L.

    Directory of Open Access Journals (Sweden)

    Tadeusz Zając

    2012-12-01

    Full Text Available In Poland the cultivation of the fibrous form of flax (Linum usitatissimum L. is dying out, but the acreage of its oilseed form, linseed, which provides seed (Semen lini used in therapy and being a source of -linolenic acid, is expanding. Nowadays, linseed is grown in 64 countries of the world, but yield levels in these countries vary greatly. Under European conditions, seed yield of linseed shows high variation, which is evidence of little knowledge of the biology of this plant and the lack of precise cultivation solutions in agricultural technologies used. A major reason is the difficulty in obtaining optimal crop density. A sparse crop results in low above-ground biomass yield, which is translated into insufficient crop yields. The selection of highly productive domestic and foreign varieties can partially increase linseed yield; apart from some domestic varieties, the Canadian cultivar 'Flanders' and the Hungarian cultivar 'Barbara' are positive examples in this respect. There is a possibility of effective selection at early stages of linseed breeding, which bodes well for the prospect of obtaining highly productive varieties with normal or very low -linolenic acid content.

  5. Modeling plant interspecific interactions from experiments with perennial crop mixtures to predict optimal combinations.

    Science.gov (United States)

    Halty, Virginia; Valdés, Matías; Tejera, Mauricio; Picasso, Valentín; Fort, Hugo

    2017-12-01

    The contribution of plant species richness to productivity and ecosystem functioning is a longstanding issue in ecology, with relevant implications for both conservation and agriculture. Both experiments and quantitative modeling are fundamental to the design of sustainable agroecosystems and the optimization of crop production. We modeled communities of perennial crop mixtures by using a generalized Lotka-Volterra model, i.e., a model such that the interspecific interactions are more general than purely competitive. We estimated model parameters -carrying capacities and interaction coefficients- from, respectively, the observed biomass of monocultures and bicultures measured in a large diversity experiment of seven perennial forage species in Iowa, United States. The sign and absolute value of the interaction coefficients showed that the biological interactions between species pairs included amensalism, competition, and parasitism (asymmetric positive-negative interaction), with various degrees of intensity. We tested the model fit by simulating the combinations of more than two species and comparing them with the polycultures experimental data. Overall, theoretical predictions are in good agreement with the experiments. Using this model, we also simulated species combinations that were not sown. From all possible mixtures (sown and not sown) we identified which are the most productive species combinations. Our results demonstrate that a combination of experiments and modeling can contribute to the design of sustainable agricultural systems in general and to the optimization of crop production in particular. © 2017 by the Ecological Society of America.

  6. Rapid evolution of manifold CRISPR systems for plant genome editing

    Directory of Open Access Journals (Sweden)

    Yiping Qi

    2016-11-01

    Full Text Available Advanced CRISPR-Cas9 based technologies first validated in mammalian cell systems are quickly being adapted for use in plants. These new technologies increase CRISPR-Cas9’s utility and effectiveness by diversifying cellular capabilities through expression construct system evolution and enzyme orthogonality, as well as enhanced efficiency through delivery and expression mechanisms. Here, we review the current state of advanced CRISPR-Cas9 and Cpf1 capabilities in plants and cover the rapid evolution of these tools from first generation inducers of double strand breaks for basic genetic manipulations to second and third generation multiplexed systems with myriad functionalities, capabilities and specialized applications. We offer perspective on how to utilize these tools for currently untested research endeavors and analyze strengths and weaknesses of novel CRISPR systems in plants. Advanced CRISPR functionalities and delivery options demonstrated in plants are primarily reviewed but new technologies just coming to the forefront of CRISPR development, or those on the horizon, are briefly discussed. Topics covered are focused on the expansion of expression and delivery capabilities for CRISPR-Cas9 components and broadening targeting range through orthogonal Cas9 and Cpf1 proteins.

  7. Polyploidy and interspecific hybridization: partners for adaptation, speciation and evolution in plants.

    Science.gov (United States)

    Alix, Karine; Gérard, Pierre R; Schwarzacher, Trude; Heslop-Harrison, J S Pat

    2017-08-01

    Polyploidy or whole-genome duplication is now recognized as being present in almost all lineages of higher plants, with multiple rounds of polyploidy occurring in most extant species. The ancient evolutionary events have been identified through genome sequence analysis, while recent hybridization events are found in about half of the world's crops and wild species. Building from this new paradigm for understanding plant evolution, the papers in this Special Issue address questions about polyploidy in ecology, adaptation, reproduction and speciation of wild and cultivated plants from diverse ecosystems. Other papers, including this review, consider genomic aspects of polyploidy. Discovery of the evolutionary consequences of new, evolutionarily recent and ancient polyploidy requires a range of approaches. Large-scale studies of both single species and whole ecosystems, with hundreds to tens of thousands of individuals, sometimes involving 'garden' or transplant experiments, are important for studying adaptation. Molecular studies of genomes are needed to measure diversity in genotypes, showing ancestors, the nature and number of polyploidy and backcross events that have occurred, and allowing analysis of gene expression and transposable element activation. Speciation events and the impact of reticulate evolution require comprehensive phylogenetic analyses and can be assisted by resynthesis of hybrids. In this Special Issue, we include studies ranging in scope from experimental and genomic, through ecological to more theoretical. The success of polyploidy, displacing the diploid ancestors of almost all plants, is well illustrated by the huge angiosperm diversity that is assumed to originate from recurrent polyploidization events. Strikingly, polyploidization often occurred prior to or simultaneously with major evolutionary transitions and adaptive radiation of species, supporting the concept that polyploidy plays a predominant role in bursts of adaptive speciation

  8. Root isolations of Metarhizium spp. from crops reflect diversity in the soil and indicate no plant specificity

    DEFF Research Database (Denmark)

    Steinwender, Bernhardt M.; Enkerli, Jürg; Widmer, Franco

    2015-01-01

    Metarhizium spp. have recently been shown to be associated with the roots of different plants. Here we evaluated which Metarhizium species were associated with roots of oat (Avena sativa), rye (Secale cereale) and cabbage (Brassica oleracea), common crop plants in Denmark. Thirty-six root samples...

  9. Sugard sorghum yield (Sorghum saccharatum (L. Pers. subject to varietal characteristics and varying plant density in crops

    Directory of Open Access Journals (Sweden)

    В. Л. Курило

    2013-08-01

    Full Text Available The example of various varieties and hybrids of sugar sorghum illustrates the summary of study on assessing varying density of plants in crops on phonological cha­racteristics of sugar sorghum plants, carbohydrate composition of sorghum juice and yield of its plants. The completed study established that one hectare of sugar sorghum, subject to varietal characteristics and varying density of plants in crop, may provide the green weight of 40.83 до 106.87 t/ha at stem juice yield of 22,27 to 56,24 t/ha, which would contain 2.31 to 6.09 t/ha of total sugars suitable for bioethanol production in at the rate of 198.25 to 501.19 dal/ha. However, despite of higher estimate of total sugars yield and bioethanol at 300 thousand plants per ha density in crop, industrial plots would preferably have plant density in crops ranging within 200...250 thousand pieces per ha. Since higher density increases dry matter content of plants, consequentially, cellulose and lignin in stems, this may create preconditions for harvest losses due to stem lod­ ging Besides, 200 thousand plants per hectare enables to reach the highest level of photosynthesis net productivity which combines high intensity of the photosynthesis with photosynthetic activity of leaf surface.

  10. LTR-retrotransposons in plants: Engines of evolution.

    Science.gov (United States)

    Galindo-González, Leonardo; Mhiri, Corinne; Deyholos, Michael K; Grandbastien, Marie-Angèle

    2017-08-30

    LTR retrotransposons are the most abundant group of transposable elements (TEs) in plants. These elements can fall inside or close to genes, and therefore influence their expression and evolution. This review aims to examine how LTR retrotransposons, especially Ty1-copia elements, mediate gene regulation and evolution. Various stimuli, including polyploidization and biotic and abiotic elicitors, result in the transcription and movement of these retrotransposons, and can facilitate adaptation. The presence of cis-regulatory motifs in the LTRs are central to their stress-mediated responses and are shared with host stress-responsive genes, showing a complex evolutionary history in which TEs provide new regulatory units to genes. The presence of retrotransposon remnants in genes that are necessary for normal gene function, demonstrates the importance of exaptation and co-option, and is also a consequence of the abundance of these elements in plant genomes. Furthermore, insertions of LTR retrotransposons in and around genes provide potential for alternative splicing, epigenetic control, transduction, duplication and recombination. These characteristics can become an active part of the evolution of gene families as in the case of resistance genes (R-genes). The character of TEs as exclusively selfish is now being re-evaluated. Since genome-wide reprogramming via TEs is a long evolutionary process, the changes we can examine are case-specific and their fitness advantage may not be evident until TE-derived motifs and domains have been completely co-opted and fixed. Nevertheless, the presence of LTR retrotransposons inside genes and as part of gene promoter regions is consistent with their roles as engines of plant genome evolution. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Genotoxic stress and DNA repair in plants: emerging functions and tools for improving crop productivity.

    Science.gov (United States)

    Balestrazzi, Alma; Confalonieri, Massimo; Macovei, Anca; Donà, Mattia; Carbonera, Daniela

    2011-03-01

    Crop productivity is strictly related to genome stability, an essential requisite for optimal plant growth/development. Genotoxic agents (e.g., chemical agents, radiations) can cause both chemical and structural damage to DNA. In some cases, they severely affect the integrity of plant genome by inducing base oxidation, which interferes with the basal processes of replication and transcription, eventually leading to cell death. The cell response to oxidative stress includes several DNA repair pathways, which are activated to remove the damaged bases and other lesions. Information concerning DNA repair in plants is still limited, although results from gene profiling and mutant analysis suggest possible differences in repair mechanisms between plants and other eukaryotes. The present review focuses on the base- and nucleotide excision repair (BER, NER) pathways, which operate according to the most common DNA repair rule (excision of damaged bases and replacement by the correct nucleotide), highlighting the most recent findings in plants. An update on DNA repair in organelles, chloroplasts and mitochondria is also provided. Finally, it is generally acknowledged that DNA repair plays a critical role during seed imbibition, preserving seed vigor. Despite this, only a limited number of studies, described here, dedicated to seeds are currently available.

  12. Uptake and translocation of Ti from nanoparticles in crops and wetland plants.

    Science.gov (United States)

    Jacob, Donna L; Borchardt, Joshua D; Navaratnam, Leelaruban; Otte, Marinus L; Bezbaruah, Achintya N

    2013-01-01

    Bioavailability of engineered metal nanoparticles affects uptake in plants, impacts on ecosystems, and phytoremediation. We studied uptake and translocation of Ti in plants when the main source of this metal was TiO2 nanoparticles. Two crops (Phaseolus vulgaris (bean) and Triticum aestivum (wheat)), a wetland species (Rumex crispus, curly dock), and the floating aquatic plant (Elodea canadensis, Canadian waterweed), were grown in nutrient solutions with TiO2 nanoparticles (0, 6, 18 mmol Ti L(-1) for P. vulgaris, T. aestivum, and R. crispus; and 0 and 12 mmol Ti L(-1) for E. canadensis). Also examined in E. canadensis was the influence of TiO2 nanoparticles upon the uptake of Fe, Mn, and Mg, and the influence of P on Ti uptake. For the rooted plants, exposure to TiO2 nanoparticles did not affect biomass production, but significantly increased root Ti sorption and uptake. R. crispus showed translocation of Ti into the shoots. E. canadensis also showed significant uptake of Ti, P in the nutrient solution significantly decreased Ti uptake, and the uptake patterns of Mn and Mg were altered. Ti from nano-Ti was bioavailable to plants, thus showing the potential for cycling in ecosystems and for phytoremediation, particularly where water is the main carrier.

  13. Biotechnological approaches to determine the impact of viruses in the energy crop plant Jatropha curcas

    Directory of Open Access Journals (Sweden)

    Maghuly Fatemeh

    2011-08-01

    Full Text Available Abstract Background Geminiviruses infect a wide range of plant species including Jatropha and cassava both belonging to family Euphorbiaceae. Cassava is traditionally an important food crop in Sub - Saharan countries, while Jatropha is considered as valuable biofuel plant with great perspectives in the future. Results A total of 127 Jatropha samples from Ethiopia and Kenya and 124 cassava samples from Kenya were tested by Enzyme-Linked Immunosorbent Assay (ELISA for RNA viruses and polymerase chain reaction for geminiviruses. Jatropha samples from 4 different districts in Kenya and Ethiopia (analyzed by ELISA were negative for all three RNA viruses tested: Cassava brown streak virus (CBSV, Cassava common mosaic virus, Cucumber mosaic virus, Three cassava samples from Busia district (Kenya contained CBSV. Efforts to develop diagnostic approaches allowing reliable pathogen detection in Jatropha, involved the amplification and sequencing of the entire DNA A molecules of 40 Kenyan isolates belonging to African cassava mosaic virus (ACMV and East African cassava mosaic virus - Uganda. This information enabled the design of novel primers to address different questions: a primers amplifying longer sequences led to a phylogenetic tree of isolates, allowing some predictions on the evolutionary aspects of Begomoviruses in Jatrophia; b primers amplifying shorter sequences represent a reliable diagnostic tool. This is the first report of the two Begomoviruses in J. curcas. Two cassava samples were co - infected with cassava mosaic geminivirus and CBSV. A Defective DNA A of ACMV was found for the first time in Jatropha. Conclusion Cassava geminiviruses occurring in Jatropha might be spread wider than anticipated. If not taken care of, this virus infection might negatively impact large scale plantations for biofuel production. Being hosts for similar pathogens, the planting vicinity of the two crop plants needs to be handled carefully.

  14. Biotechnological approaches to determine the impact of viruses in the energy crop plant Jatropha curcas

    Science.gov (United States)

    2011-01-01

    Background Geminiviruses infect a wide range of plant species including Jatropha and cassava both belonging to family Euphorbiaceae. Cassava is traditionally an important food crop in Sub - Saharan countries, while Jatropha is considered as valuable biofuel plant with great perspectives in the future. Results A total of 127 Jatropha samples from Ethiopia and Kenya and 124 cassava samples from Kenya were tested by Enzyme-Linked Immunosorbent Assay (ELISA) for RNA viruses and polymerase chain reaction for geminiviruses. Jatropha samples from 4 different districts in Kenya and Ethiopia (analyzed by ELISA) were negative for all three RNA viruses tested: Cassava brown streak virus (CBSV), Cassava common mosaic virus, Cucumber mosaic virus, Three cassava samples from Busia district (Kenya) contained CBSV. Efforts to develop diagnostic approaches allowing reliable pathogen detection in Jatropha, involved the amplification and sequencing of the entire DNA A molecules of 40 Kenyan isolates belonging to African cassava mosaic virus (ACMV) and East African cassava mosaic virus - Uganda. This information enabled the design of novel primers to address different questions: a) primers amplifying longer sequences led to a phylogenetic tree of isolates, allowing some predictions on the evolutionary aspects of Begomoviruses in Jatrophia; b) primers amplifying shorter sequences represent a reliable diagnostic tool. This is the first report of the two Begomoviruses in J. curcas. Two cassava samples were co - infected with cassava mosaic geminivirus and CBSV. A Defective DNA A of ACMV was found for the first time in Jatropha. Conclusion Cassava geminiviruses occurring in Jatropha might be spread wider than anticipated. If not taken care of, this virus infection might negatively impact large scale plantations for biofuel production. Being hosts for similar pathogens, the planting vicinity of the two crop plants needs to be handled carefully. PMID:21812981

  15. A targeted management of the nutrient solution in a soilless tomato crop according to plant needs

    Directory of Open Access Journals (Sweden)

    Angelo eSignore

    2016-03-01

    Full Text Available The adoption of closed soilless systems is useful in minimizing the environmental impact of the greenhouse crops. Instead, a significant problem in closed soilless systems is represented by the accumulation of ions in the recycled nutrient solution, in particular the unabsorbed or poorly absorbed ones. To overcome such problem, we: 1 studied the effect of several values of the electrical conductivity (EC of nutrient solution in a NFT (Nutrient Film Technique system on a cherry type tomato crop, and 2 define a NS (called recovery solution, based on the concept of uptake concentration and transpiration-biomass ratio, that fits the real needs of the plant with respect to water and nutrients. Three levels of EC set point (SP, above which the NS was completely replaced (SP5, SP7.5, and SP10 for the EC limit of 5, 7.5 and 10 dS m-1, respectively, were established. The SP10 treatment yield was not different from other treatments, and it allowed a better quality of the berries (for dry matter and total soluble solids and higher environmental sustainability due to a lower discharge of total nutrients into the environment (37 and 59% with respect to SP7.5 and SP5, respectively.The recovery solution used in the second trial allowed a more punctual NS management, by adapting to the real needs of the crop. Moreover, it allowed a lesser amount of water and nutrients to be discharged into the environment and a better use of brackish water, due to a more accurate management of the EC of the NS. The targeted management, based on transpiration-biomass ratio, indicates that, in some stages of the plant cycle, the nutrient solution used can be diluted, in order to save water and nutrients. With such management a closed cycle can be realized without affecting the yield, but improving the quality of the tomato berries.

  16. Population Dynamics of Plant-parasitic Nematodes on Cover Crops of Corn and Sorghum.

    Science.gov (United States)

    McSorley, R; Gallaher, R N

    1993-09-01

    Buildup of plant-parasitic nematode populations on corn (Zea mays), soybean (Glycine max), and sorghum (Sorghum bicolor) were compared in 1991 and 1992. Final population densities (Pf) of Meloidogyne incognita were lower following sorghum than after soybean in both seasons, and Pf after sorghum was lower than Pf after corn in 1992. In both seasons, Pf differed among the sorghum cultivars used. No differences in Pf on corn, sorghum, and soybean were observed for Criconemella spp. (a mixture of C. sphaerocephala and C. ornata) or Paratrichodorus minor in either season. Pf levels of Pratylenchus spp. (a mixture of P. brachyurus and P. scribneri) were greatest after corn in 1992, but no differences with crop treatments were observed in 1991. When data from field tests conducted with corn and sorghum during the past four seasons were pooled, negative linear relationships between ln(Pf/Pi) and ln(Pi) were observed for Criconemella spp. and P. minor on each crop, and for M. incognita on corn (Pi = initial population density). Although ln(Pf/Pi) and ln(Pi) were not related for M. incognita with pooled sorghum data, separate relationships were derived for various sorghum cultivars. Regression equations from pooled data were used to obtain estimates of equilibrium density and maximum reproductive rate, and these estimates were used to construct models expressing nematode Pf across a range of initial densities. Many of these models were robust, encompassing a range of sites, season, crop cultivars, and planting dates. Quadratic models derived from pooled field data provided an alternative method for expressing Pf as a function of Pi.

  17. Diversity, biocontrol, and plant growth promoting abilities of xylem residing bacteria from solanaceous crops.

    Science.gov (United States)

    Achari, Gauri A; Ramesh, Raman

    2014-01-01

    Eggplant (Solanum melongena L.) is one of the solanaceous crops of economic and cultural importance and is widely cultivated in the state of Goa, India. Eggplant cultivation is severely affected by bacterial wilt caused by Ralstonia solanacearum that colonizes the xylem tissue. In this study, 167 bacteria were isolated from the xylem of healthy eggplant, chilli, and Solanum torvum Sw. by vacuum infiltration and maceration. Amplified rDNA restriction analysis (ARDRA) grouped these xylem residing bacteria (XRB) into 38 haplotypes. Twenty-eight strains inhibited growth of R. solanacearum and produced volatile and diffusible antagonistic compounds and plant growth promoting substances in vitro. Antagonistic strains XB86, XB169, XB177, and XB200 recorded a biocontrol efficacy greater than 85% against BW and exhibited 12%-22 % increase in shoot length in eggplant in the greenhouse screening. 16S rRNA based identification revealed the presence of 23 different bacterial genera. XRB with high biocontrol and plant growth promoting activities were identified as strains of Staphylococcus sp., Bacillus sp., Streptomyces sp., Enterobacter sp., and Agrobacterium sp. This study is the first report on identity of bacteria from the xylem of solanaceous crops having traits useful in cultivation of eggplant.

  18. Diversity, Biocontrol, and Plant Growth Promoting Abilities of Xylem Residing Bacteria from Solanaceous Crops

    Directory of Open Access Journals (Sweden)

    Gauri A. Achari

    2014-01-01

    Full Text Available Eggplant (Solanum melongena L. is one of the solanaceous crops of economic and cultural importance and is widely cultivated in the state of Goa, India. Eggplant cultivation is severely affected by bacterial wilt caused by Ralstonia solanacearum that colonizes the xylem tissue. In this study, 167 bacteria were isolated from the xylem of healthy eggplant, chilli, and Solanum torvum Sw. by vacuum infiltration and maceration. Amplified rDNA restriction analysis (ARDRA grouped these xylem residing bacteria (XRB into 38 haplotypes. Twenty-eight strains inhibited growth of R. solanacearum and produced volatile and diffusible antagonistic compounds and plant growth promoting substances in vitro. Antagonistic strains XB86, XB169, XB177, and XB200 recorded a biocontrol efficacy greater than 85% against BW and exhibited 12%–22 % increase in shoot length in eggplant in the greenhouse screening. 16S rRNA based identification revealed the presence of 23 different bacterial genera. XRB with high biocontrol and plant growth promoting activities were identified as strains of Staphylococcus sp., Bacillus sp., Streptomyces sp., Enterobacter sp., and Agrobacterium sp. This study is the first report on identity of bacteria from the xylem of solanaceous crops having traits useful in cultivation of eggplant.

  19. Ecogeography and utility to plant breeding of the crop wild relatives of sunflower (Helianthus annuus L.)

    Science.gov (United States)

    Kantar, Michael B.; Sosa, Chrystian C.; Khoury, Colin K.; Castañeda-Álvarez, Nora P.; Achicanoy, Harold A.; Bernau, Vivian; Kane, Nolan C.; Marek, Laura; Seiler, Gerald; Rieseberg, Loren H.

    2015-01-01

    Crop wild relatives (CWR) are a rich source of genetic diversity for crop improvement. Combining ecogeographic and phylogenetic techniques can inform both conservation and breeding. Geographic occurrence, bioclimatic, and biophysical data were used to predict species distributions, range overlap and niche occupancy in 36 taxa closely related to sunflower (Helianthus annuus L.). Taxa lacking comprehensive ex situ conservation were identified. The predicted distributions for 36 Helianthus taxa identified substantial range overlap, range asymmetry and niche conservatism. Specific taxa (e.g., Helianthus deblis Nutt., Helianthus anomalus Blake, and Helianthus divaricatus L.) were identified as targets for traits of interest, particularly for abiotic stress tolerance, and adaptation to extreme soil properties. The combination of techniques demonstrates the potential for publicly available ecogeographic and phylogenetic data to facilitate the identification of possible sources of abiotic stress traits for plant breeding programs. Much of the primary genepool (wild H. annuus) occurs in extreme environments indicating that introgression of targeted traits may be relatively straightforward. Sister taxa in Helianthus have greater range overlap than more distantly related taxa within the genus. This adds to a growing body of literature suggesting that in plants (unlike some animal groups), geographic isolation may not be necessary for speciation. PMID:26500675

  20. Biochar potential in intensive cultivation of Capsicum annuum L. (sweet pepper): crop yield and plant protection.

    Science.gov (United States)

    Kumar, Abhay; Elad, Yigal; Tsechansky, Ludmila; Abrol, Vikas; Lew, Beni; Offenbach, Rivka; Graber, Ellen R

    2018-01-01

    The influence of various biochars on crop yield and disease resistance of Capsicum annuum L. (sweet pepper) under modern, high input, intensive net house cultivation was tested over the course of 2011-2014 in the Arava desert region of Israel. A pot experiment with Lactuca sativa L. (lettuce) grown in the absence of fertilizer employed the 3-year-old field trial soils to determine if biochar treatments contributed to soil intrinsic fertility. Biochar amendments resulted in a significant increase in the number and weight of pepper fruits over 3 years. Concomitant with the increased yield, biochar significantly decreased the severity of powdery mildew (Leveillula taurica) disease and broad mite (Polyphagotarsonemus latus) pest infestation. Biochar additions resulted in increased soil organic matter but did not influence the pH, electrical conductivity or soil or plant mineral nutrients. Intrinsic fertility experiments with lettuce showed that two of the four biochar-treated field soils had significant positive impacts on lettuce fresh weight and total chlorophyll, carotenoid and anthocyanin contents. Biochar-based soil management can enhance the functioning of intensive, commercial, net house production of peppers under the tested conditions, resulting in increased crop yield and plant resistance to disease over several years. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  1. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Directory of Open Access Journals (Sweden)

    Xin Liu

    Full Text Available Modelling crop evapotranspiration (ET response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1 and summer maize (scenario 2 by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  2. Effect of crop development on biogenic emissions from plant populations grown in closed plant growth chambers

    Science.gov (United States)

    Batten, J. H.; Stutte, G. W.; Wheeler, R. M.

    1995-01-01

    The Biomass Production Chamber at John F. Kennedy Space Center is a closed plant growth chamber facility that can be used to monitor the level of biogenic emissions from large populations of plants throughout their entire growth cycle. The head space atmosphere of a 26-day-old lettuce (Lactuca sativa cv. Waldmann's Green) stand was repeatedly sampled and emissions identified and quantified using GC-mass spectrometry. Concentrations of dimethyl sulphide, carbon disulphide, alpha-pinene, furan and 2-methylfuran were not significantly different throughout the day; whereas, isoprene showed significant differences in concentration between samples collected in light and dark periods. Volatile organic compounds from the atmosphere of wheat (Triticum aestivum cv. Yecora Rojo) were analysed and quantified from planting to maturity. Volatile plant-derived compounds included 1-butanol, 2-ethyl-1-hexanol, nonanal, benzaldehyde, tetramethylurea, tetramethylthiourea, 2-methylfuran and 3-methylfuran. Concentrations of volatiles were determined during seedling establishment, vegetative growth, anthesis, grain fill and senescence and found to vary depending on the developmental stage. Atmospheric concentrations of benzaldehyde and nonanal were highest during anthesis, 2-methylfuran and 3-methylfuran concentrations were greatest during grain fill, and the concentration of the tetramethylurea peaked during senescence.

  3. High yielding tropical energy crops for bioenergy production: Effects of plant components, harvest years and locations on biomass composition.

    Science.gov (United States)

    Surendra, K C; Ogoshi, Richard; Zaleski, Halina M; Hashimoto, Andrew G; Khanal, Samir Kumar

    2017-12-18

    The composition of lignocellulosic feedstock, which depends on crop type, crop management, locations and plant parts, significantly affects the conversion efficiency of biomass into biofuels and biobased products. Thus, this study examined the composition of different parts of two high yielding tropical energy crops, Energycane and Napier grass, collected across three locations and years. Significantly higher fiber content was found in the leaves of Energycane than stems, while fiber content was significantly higher in the stems than the leaves of Napier grass. Similarly, fiber content was higher in Napier grass than Energycane. Due to significant differences in biomass composition between the plant parts within a crop type, neither biological conversion, including anaerobic digestion, nor thermochemical pretreatment alone is likely to efficiently convert biomass components into biofuels and biobased products. However, combination of anaerobic digestion with thermochemical conversion technologies could efficiently utilize biomass components in generating biofuels and biobased products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Enhancing crop yield with the use of N-based fertilizers co-applied with plant hormones or growth regulators.

    Science.gov (United States)

    Zaman, Mohammad; Kurepin, Leonid V; Catto, Warwick; Pharis, Richard P

    2015-07-01

    Crop yield, vegetative or reproductive, depends on access to an adequate supply of essential mineral nutrients. At the same time, a crop plant's growth and development, and thus yield, also depend on in situ production of plant hormones. Thus optimizing mineral nutrition and providing supplemental hormones are two mechanisms for gaining appreciable yield increases. Optimizing the mineral nutrient supply is a common and accepted agricultural practice, but the co-application of nitrogen-based fertilizers with plant hormones or plant growth regulators is relatively uncommon. Our review discusses possible uses of plant hormones (gibberellins, auxins, cytokinins, abscisic acid and ethylene) and specific growth regulators (glycine betaine and polyamines) to enhance and optimize crop yield when co-applied with nitrogen-based fertilizers. We conclude that use of growth-active gibberellins, together with a nitrogen-based fertilizer, can result in appreciable and significant additive increases in shoot dry biomass of crops, including forage crops growing under low-temperature conditions. There may also be a potential for use of an auxin or cytokinin, together with a nitrogen-based fertilizer, for obtaining additive increases in dry shoot biomass and/or reproductive yield. Further research, though, is needed to determine the potential of co-application of nitrogen-based fertilizers with abscisic acid, ethylene and other growth regulators. © 2014 Society of Chemical Industry.

  5. Biotechnological applications in in vitro plant regeneration studies of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

    Science.gov (United States)

    Kumar, Pankaj; Srivastava, Dinesh Kumar

    2016-04-01

    Biotechnology holds promise for genetic improvement of important vegetable crops. Broccoli (Brassica oleracea L. var. italica) is an important vegetable crop of the family Brassicaceae. However, various biotic and abiotic stresses cause enormous crop yield losses during commercial cultivation of broccoli. Establishment of a reliable, reproducible and efficient in vitro plant regeneration system with cell and tissue culture is a vital prerequisite for biotechnological application of crop improvement programme. An in vitro plant regeneration technique refers to culturing, cell division, cell multiplication, de-differentiation and differentiation of cells, protoplasts, tissues and organs on defined liquid/solid medium under aseptic and controlled environment. Recent progress in the field of plant tissue culture has made this area one of the most dynamic and promising in experimental biology. There are many published reports on in vitro plant regeneration studies in broccoli including direct organogenesis, indirect organogenesis and somatic embryogenesis. This review summarizes those plant regeneration studies in broccoli that could be helpful in drawing the attention of the researchers and scientists to work on it to produce healthy, biotic and abiotic stress resistant plant material and to carry out genetic transformation studies for the production of transgenic plants.

  6. Tempo and mode in plant breeding system evolution.

    Science.gov (United States)

    Goldberg, Emma E; Igić, Boris

    2012-12-01

    Classic questions about trait evolution-including the directionality of character change and its interactions with lineage diversification-intersect in the study of plant breeding systems. Transitions from self-incompatibility to self-compatibility are frequent, and they may proceed within a species ("anagenetic" mode of breeding system change) or in conjunction with speciation events ("cladogenetic" mode of change). We apply a recently developed phylogenetic model to the nightshade family Solanaceae, quantifying the relative contributions of these two modes of evolution along with the tempo of breeding system change, speciation, and extinction. We find that self-incompatibility, a genetic mechanism that prevents self-fertilization, is lost largely by the cladogenetic mode. Self-compatible species are thus more likely to arise from the isolation of a newly self-compatible population than from species-wide fixation of self-compatible mutants. Shared polymorphism at the locus that governs self-incompatibility shows it to be ancestral and not regained within this family. We demonstrate that failing to account for cladogenetic character change misleads phylogenetic tests of evolutionary irreversibility, both for breeding system in Solanaceae and on simulated trees. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  7. Soil-to-Plant Transfer Factors of {sup 99}Tc for Korean Major Upland Crops

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yong Ho; Lim, Kwang Muk; Jun, In; Keum, Dong Kwon [Korea Atomic Energy Reserach Institute, Daejeon (Korea, Republic of)

    2011-12-15

    In order to investigate the soil-to-plant transfer factor (TF) of {sup 99}Tc for Korean major upland crops (soybean, radish and Chinese cabbage), pot experiments were performed in a greenhouse. Soils were collected from four upland fields (two for soybean and two for radish and Chinese cabbage) around Gyeongju radioactive-waste disposal site. Three to four weeks before sowing, dried soils were mixed with a {sup 99}Tc solution and the mixtures were put into pots and irrigated. TF values were expressed as the ratios of the {sup 99}Tc concentrations in plants (Bq kg{sup -1}-dry or fresh) to those in soils (Bq kg{sup -1}-dry). There was no great difference in the TF value between soils. The TF values for soybean seeds were extremely lower than those for the straws, indicating a very low mobility of {sup 99}Tc to seeds. As representative TF values of{sup 99}Tc,1.8 X 10{sup -1}, 1.2 X 10{sup 1}, 3.2 X 10{sup 2} and 1.3 X 10{sup 2} (for dry plants), arithmetic means for two soils, were proposed for soybean seeds, radish roots, radish leaves and Chinese cabbage leaves, respectively. In the case of the vegetables, proposals for fresh plants were also made. The proposed values are not sufficiently representative so successive updates are needed.

  8. Next biotech plants: new traits, crops, developers and technologies for addressing global challenges.

    Science.gov (United States)

    Ricroch, Agnès E; Hénard-Damave, Marie-Cécile

    2016-08-01

    Most of the genetically modified (GM) plants currently commercialized encompass a handful of crop species (soybean, corn, cotton and canola) with agronomic characters (traits) directed against some biotic stresses (pest resistance, herbicide tolerance or both) and created by multinational companies. The same crops with agronomic traits already on the market today will continue to be commercialized, but there will be also a wider range of species with combined traits. The timeframe anticipated for market release of the next biotech plants will not only depend on science progress in research and development (R&D) in laboratories and fields, but also primarily on how demanding regulatory requirements are in countries where marketing approvals are pending. Regulatory constraints, including environmental and health impact assessments, have increased significantly in the past decades, delaying approvals and increasing their costs. This has sometimes discouraged public research entities and small and medium size plant breeding companies from using biotechnology and given preference to other technologies, not as stringently regulated. Nevertheless, R&D programs are flourishing in developing countries, boosted by the necessity to meet the global challenges that are food security of a booming world population while mitigating climate change impacts. Biotechnology is an instrument at the service of these imperatives and a wide variety of plants are currently tested for their high yield despite biotic and abiotic stresses. Many plants with higher water or nitrogen use efficiency, tolerant to cold, salinity or water submergence are being developed. Food security is not only a question of quantity but also of quality of agricultural and food products, to be available and accessible for the ones who need it the most. Many biotech plants (especially staple food) are therefore being developed with nutritional traits, such as biofortification in vitamins and metals. The main

  9. A photorespiratory bypass increases plant growth and seed yield in biofuel crop Camelina sativa.

    Science.gov (United States)

    Dalal, Jyoti; Lopez, Harry; Vasani, Naresh B; Hu, Zhaohui; Swift, Jennifer E; Yalamanchili, Roopa; Dvora, Mia; Lin, Xiuli; Xie, Deyu; Qu, Rongda; Sederoff, Heike W

    2015-01-01

    Camelina sativa is an oilseed crop with great potential for biofuel production on marginal land. The seed oil from camelina has been converted to jet fuel and improved fuel efficiency in commercial and military test flights. Hydrogenation-derived renewable diesel from camelina is environmentally superior to that from canola due to lower agricultural inputs, and the seed meal is FDA approved for animal consumption. However, relatively low yield makes its farming less profitable. Our study is aimed at increasing camelina seed yield by reducing carbon loss from photorespiration via a photorespiratory bypass. Genes encoding three enzymes of the Escherichia coli glycolate catabolic pathway were introduced: glycolate dehydrogenase (GDH), glyoxylate carboxyligase (GCL) and tartronic semialdehyde reductase (TSR). These enzymes compete for the photorespiratory substrate, glycolate, convert it to glycerate within the chloroplasts, and reduce photorespiration. As a by-product of the reaction, CO2 is released in the chloroplast, which increases photosynthesis. Camelina plants were transformed with either partial bypass (GDH), or full bypass (GDH, GCL and TSR) genes. Transgenic plants were evaluated for physiological and metabolic traits. Expressing the photorespiratory bypass genes in camelina reduced photorespiration and increased photosynthesis in both partial and full bypass expressing lines. Expression of partial bypass increased seed yield by 50-57 %, while expression of full bypass increased seed yield by 57-73 %, with no loss in seed quality. The transgenic plants also showed increased vegetative biomass and faster development; they flowered, set seed and reached seed maturity about 1 week earlier than WT. At the transcriptional level, transgenic plants showed differential expression in categories such as respiration, amino acid biosynthesis and fatty acid metabolism. The increased growth of the bypass transgenics compared to WT was only observed in ambient or low CO

  10. Plants + soil/wetland microbes: Food crop systems that also clean air and water

    Science.gov (United States)

    Nelson, Mark; Wolverton, B. C.

    2011-02-01

    The limitations that will govern bioregenerative life support applications in space, especially volume and weight, make multi-purpose systems advantageous. This paper outlines two systems which utilize plants and associated microbial communities of root or growth medium to both produce food crops and clean air and water. Underlying these approaches are the large numbers and metabolic diversity of microbes associated with roots and found in either soil or other suitable growth media. Biogeochemical cycles have microbial links and the ability of microbes to metabolize virtually all trace gases, whether of technogenic or biogenic origin, has long been established. Wetland plants and the rootzone microbes of wetland soils/media also been extensively researched for their ability to purify wastewaters of a great number of potential water pollutants, from nutrients like N and P, to heavy metals and a range of complex industrial pollutants. There is a growing body of research on the ability of higher plants to purify air and water. Associated benefits of these approaches is that by utilizing natural ecological processes, the cleansing of air and water can be done with little or no energy inputs. Soil and rootzone microorganisms respond to changing pollutant types by an increase of the types of organisms with the capacity to use these compounds. Thus living systems have an adaptive capacity as long as the starting populations are sufficiently diverse. Tightly sealed environments, from office buildings to spacecraft, can have hundreds or even thousands of potential air pollutants, depending on the materials and equipment enclosed. Human waste products carry a plethora of microbes which are readily used in the process of converting its organic load to forms that can be utilized by green plants. Having endogenous means of responding to changing air and water quality conditions represents safety factors as these systems operate without the need for human intervention. We review

  11. Plants + microbes: Innovative food crop systems that also clean air and water

    Science.gov (United States)

    Nelson, Mark; Wolverton, B. C.

    The limitations that will govern bioregenerative life support applications in space, especially volume and weight, make multi-purpose systems advantageous. This paper outlines two systems which utilize plants and associated microbial communities of root or growth medium to both produce food crops and clean air and water. Underlying these approaches are the large numbers and metabolic diversity of microbes associated with roots and found in either soil or other suitable growth media. It is known that most biogeochemical cycles have a microbial link, and the ability of microbes to metabolize virtually all trace gases, whether of technogenic or biogenic origin, have long been established. Wetland plants and soil/media also been extensively researched for their ability to purify wastewaters of all kinds of potential water pollutants, from nutrients like N and P, to heavy metals and a range of complex industrial pollutants. There is a growing body of research on the ability of higher plants to purify air and water. Associated benefits of these approaches is that by utilizing natural ecological processes, the cleansing of air and water can be done with little or no energy inputs. Soil and root microorganisms respond to changing pollutant types by an increase of the types of organisms with the capacity to use these compounds. Thus living systems have an extraordinary adaptive capacity as long as the starting populations are sufficiently diverse. It is known that tightly sealed environments, from office buildings to spacecraft, can have hundreds or even thousands of potential air pollutants, depending on the materials and machines enclosed. Human waste products carry a plethora of microbes can are readily used in the process of converting its organic load to forms that can be utilized by green plants. Having endogenous means of responding to changing air and water quality conditions represents safety factors which operate without the need for human direction. We will

  12. A history of plant biotechnology: from the Cell Theory of Schleiden and Schwann to biotech crops.

    Science.gov (United States)

    Vasil, Indra K

    2008-09-01

    Plant biotechnology is founded on the principles of cellular totipotency and genetic transformation, which can be traced back to the Cell Theory of Matthias Jakob Schleiden and Theodor Schwann, and the discovery of genetic transformation in bacteria by Frederick Griffith, respectively. On the 25th anniversary of the genetic transformation of plants, this review provides a historical account of the evolution of the theoretical concepts and experimental strategies that led to the production and commercialization of biotech (transformed or transgenic) plants expressing many useful genes, and emphasizes the beneficial effects of plant biotechnology on food security, human health, the environment, and conservation of biodiversity. In so doing, it celebrates and pays tribute to the contributions of scores of scientists who laid the foundation of modern plant biotechnology by their bold and unconventional thinking and experimentation. It highlights also the many important lessons to be learnt from the fascinating history of plant biotechnology, the significance of history in science teaching and research, and warns against the danger of the growing trends of ignoring history and historical illiteracy.

  13. The evolution of the plant genome-to-morphology auxin circuit.

    Science.gov (United States)

    Kutschera, Ulrich; Niklas, Karl J

    2016-09-01

    In his Generelle Morphologie der Organismen (1866), 150 years ago, Ernst Haeckel (1834-1919) combined developmental patterns in animals with the concept of organismic evolution, and 50 years ago, a new era of plant research started when focus shifted from crop species (sunflower, maize etc.) to thale cress (Arabidopsis thaliana) as a model organism. In this contribution, we outline the general principles of developmental evolutionary biology sensu Haeckel and describe the evolutionary genome-to-morphology-plant hormone auxin (IAA, indole-3-acetic acid)-circuit with reference to other phytohormones and a focus on land plants (embryophytes) plus associated epiphytic microbes. Our primary conclusion is that a system-wide approach is required to truly understand the ontogeny of any organism, because development proceeds according to signal pathways that integrate and respond to external as well as internal stimuli. We also discuss IAA-regulated embryology in A. thaliana and epigenetic phenomena in the gametophyte development, and outline how these processes are connected to the seminal work of Ernst Haeckel.

  14. Functional Roles of microRNAs in Agronomically Important Plants-Potential as Targets for Crop Improvement and Protection.

    Science.gov (United States)

    Djami-Tchatchou, Arnaud T; Sanan-Mishra, Neeti; Ntushelo, Khayalethu; Dubery, Ian A

    2017-01-01

    MicroRNAs (miRNAs) are a class of small non-coding RNAs that have recently emerged as important regulators of gene expression, mainly through cleavage and/or translation inhibition of the target mRNAs during or after transcription. miRNAs play important roles by regulating a multitude of biological processes in plants which include maintenance of genome integrity, development, metabolism, and adaptive responses toward environmental stresses. The increasing population of the world and their food demands requires focused efforts for the improvement of crop plants to ensure sustainable food production. Manipulation of mRNA transcript abundance via miRNA control provides a unique strategy for modulating differential plant gene expression and miRNAs are thus emerging as the next generation targets for genetic engineering for improvement of the agronomic properties of crops. However, a deeper understanding of its potential and the mechanisms involved will facilitate the design of suitable strategies to obtain the desirable traits with minimum trade-offs in the modified crops. In this regard, this review highlights the diverse roles of conserved and newly identified miRNAs in various food and industrial crops and recent advances made in the uses of miRNAs to improve plants of agronomically importance so as to significantly enhance crop yields and increase tolerance to various environmental stress agents of biotic-or abiotic origin.

  15. Community evolution increases plant productivity at low diversity.

    Science.gov (United States)

    van Moorsel, Sofia J; Hahl, Terhi; Wagg, Cameron; De Deyn, Gerlinde B; Flynn, Dan F B; Zuppinger-Dingley, Debra; Schmid, Bernhard

    2018-01-01

    Species extinctions from local communities negatively affect ecosystem functioning. Ecological mechanisms underlying these impacts are well studied, but the role of evolutionary processes is rarely assessed. Using a long-term field experiment, we tested whether natural selection in plant communities increased biodiversity effects on productivity. We re-assembled communities with 8-year co-selection history adjacent to communities with identical species composition but no history of co-selection ('naïve communities'). Monocultures, and in particular mixtures of two to four co-selected species, were more productive than their corresponding naïve communities over 4 years in soils with or without co-selected microbial communities. At the highest diversity level of eight plant species, no such differences were observed. Our findings suggest that plant community evolution can lead to rapid increases in ecosystem functioning at low diversity but may take longer at high diversity. This effect was not modified by treatments simulating co-evolutionary processes between plants and soil organisms. © 2017 John Wiley & Sons Ltd/CNRS.

  16. Divergence and Conservative Evolution of XTNX Genes in Land Plants

    Directory of Open Access Journals (Sweden)

    Yan-Mei Zhang

    2017-10-01

    Full Text Available The Toll-interleukin-1 receptor (TIR and Nucleotide-binding site (NBS domains are two major components of the TIR-NBS-leucine-rich repeat family plant disease resistance genes. Extensive functional and evolutionary studies have been performed on these genes; however, the characterization of a small group of genes that are composed of atypical TIR and NBS domains, namely XTNX genes, is limited. The present study investigated this specific gene family by conducting genome-wide analyses of 59 green plant genomes. A total of 143 XTNX genes were identified in 51 of the 52 land plant genomes, whereas no XTNX gene was detected in any green algae genomes, which indicated that XTNX genes originated upon emergence of land plants. Phylogenetic analysis revealed that the ancestral XTNX gene underwent two rounds of ancient duplications in land plants, which resulted in the formation of clades I/II and clades IIa/IIb successively. Although clades I and IIb have evolved conservatively in angiosperms, the motif composition difference and sequence divergence at the amino acid level suggest that functional divergence may have occurred since the separation of the two clades. In contrast, several features of the clade IIa genes, including the absence in the majority of dicots, the long branches in the tree, the frequent loss of ancestral motifs, and the loss of expression in all detected tissues of Zea mays, all suggest that the genes in this lineage might have undergone pseudogenization. This study highlights that XTNX genes are a gene family originated anciently in land plants and underwent specific conservative pattern in evolution.

  17. Plant probiotic bacteria enhance the quality of fruit and horticultural crops

    Directory of Open Access Journals (Sweden)

    Alejandro Jiménez-Gómez

    2017-06-01

    Full Text Available The negative effects on the environment and human health caused by the current farming systems based on the overuse of chemical fertilizers have been reported in many studies. By contrast, bacterial inoculations produce positive effects on yields without causing this type of harm. Hence, during recent years, the commercialization of biofertilizers has been on the increase, and the number of companies and products available are expanding worldwide every year. In addition to the notable enhancement of crop production, many studies have shown how the application of bacteria has positive effects on food quality such as improved vitamin, flavonoid and antioxidant content, among other benefits. This advantage is interesting with respect to food that is consumed raw, such as fruits and many vegetables, as these bioactive molecules are maintained up until the moment the food is consumed. As regards this review focuses on the collection of studies that demonstrate that microorganisms can act as plant probiotics of fruit and horticultural crops, essential types of food that form part of a healthy diet.

  18. Mite Pests in Plant Crops – Current Issues, Inovative Approaches and Possibilities for Controlling Them (1

    Directory of Open Access Journals (Sweden)

    Radmila Petanović

    2010-01-01

    Full Text Available In the middle of the last century, mites moved into the focus of attention as pests relevantto agriculture, forestry and landscape horticulture, presumably in direct reactionto the “green revolution” that involved plant cultivation in large-plot monocropping systems,improved methods of cultivation, selection of high-yielding cultivars and intensifieduse of pesticides and mineral fertilizers. Agroecosystems in which phytophagous miteshave become harmful organisms are primarily orchards, vineyards, greenhouses, urbangreeneries, plant nurseries and stored plant products, as well as annual field crops to asomewhat lesser degree. Phytophagous mite species belong to a variety of spider mites(Tetranychidae, false spider mites (Tenuipalpidae, gall and rust mites (Eriophyoidae, tarsonemidmites (Tarsonemidae and acarid mites (Acaridae. Most of these harmful speciesare widespread, some of them having more economic impact than others and being moredetrimental as depending on various specificities of each outdoor agroecosystem in anyparticular climatic region.The first segment of this overview focuses on the most significant mite pests ofagroecosystemsand urban horticultural areas in European countries, our own region andin Serbia today, primarily on species that have caused problems in recent years regardingplant production, and it also discusses various molecular methods available for investigatingdifferent aspects of the biology of phytophagous mites. Also, acaricides are discussedas a method of controlling mite pests in the light of the current situation and trends on pesticidemarkets in Serbia and the European Union member-countries

  19. Location of Bioelectricity Plants in the Madrid Community Based on Triticale Crop: A Multicriteria Methodology

    Directory of Open Access Journals (Sweden)

    L. Romero

    2015-01-01

    Full Text Available This paper presents a work whose objective is, first, to quantify the potential of the triticale biomass existing in each of the agricultural regions in the Madrid Community through a crop simulation model based on regression techniques and multiple correlation. Second, a methodology for defining which area has the best conditions for the installation of electricity plants from biomass has been described and applied. The study used a methodology based on compromise programming in a discrete multicriteria decision method (MDM context. To make a ranking, the following criteria were taken into account: biomass potential, electric power infrastructure, road networks, protected spaces, and urban nuclei surfaces. The results indicate that, in the case of the Madrid Community, the Campiña region is the most suitable for setting up plants powered by biomass. A minimum of 17,339.9 tons of triticale will be needed to satisfy the requirements of a 2.2 MW power plant. The minimum range of action for obtaining the biomass necessary in Campiña region would be 6.6 km around the municipality of Algete, based on Geographic Information Systems. The total biomass which could be made available in considering this range in this region would be 18,430.68 t.

  20. [Biodiversity of phosphate-dissolving and plant growth--promoting endophytic bacteria of two crops].

    Science.gov (United States)

    Huang, Jing; Sheng, Xiafang; He, Linyan

    2010-06-01

    We isolated and characterized phosphate-dissolving endophytic bacteria from two commonly cultivated crops. Phosphate-dissolving endophytic bacteria were isolated by plating and screening from interior tissues of rape and maize plants on NBRIP medium with tricalcium phosphate as sole phosphate source. Bacteria were characterized regarding characteristics that may be relevant for a beneficial plant-microbe interaction-indoleacetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase production,and further classified by restriction analysis of 16S rDNA. Eleven typical strains were identified by 16S rDNA sequence analysis. Thirty-two phosphate-dissolving endophytic bacteria were isolated from maize and rape plants and classified by restriction analysis of 16S rDNA in 8 different taxonomic groups at the similarity level of 76%. All the isolates could release phosphate from tricalcium phosphate and decrease the pH of the medium. The maximum phosphate content (537.6 mg/L) in the solution was obtained with strain M1L5. Thirteen isolates isolated from rape produced indoleacetic acid and siderophore, 68.4% and 63.2% of the strains isolated from maize produced indoleacetic acid and siderophore,respectively. 63.2% of the strains isolated from maize were able to grow on 1-aminocyclopropane-1-carboxylic acid as the sole nitrogen source. The eleven strains belonged to five different genera including Pantoea, Pseudomonas, Burkholderia, Acinetobacter and Ralstonia. Phosphate-dissolving endophytic bacteria isolated from rape and maize plants have abundant characteristics relative to promoting plant growth and genetic diversity.

  1. Using The Corngrass1 Gene To Enhance The Biofuel Properties Of Crop Plants

    Energy Technology Data Exchange (ETDEWEB)

    Hake, Sarah [USDA Agricultural Research Service, Washington DC (United States); Chuck, George [USDA Agricultural Research Service, Washington DC (United States)

    2015-10-29

    The development of novel plant germplasm is vital to addressing our increasing bioenergy demands. The major hurdle to digesting plant biomass is the complex structure of the cell walls, the substrate of fermentation. Plant cell walls are inaccessible matrices of macromolecules that are polymerized with lignin, making fermentation difficult. Overcoming this hurdle is a major goal toward developing usable bioenergy crop plants. Our project seeks to enhance the biofuel properties of perennial grass species using the Corngrass1 (Cg1) gene and its targets. Dominant maize Cg1 mutants produce increased biomass by continuously initiating extra axillary meristems and leaves. We cloned Cg1 and showed that its phenotype is caused by over expression of a unique miR156 microRNA gene that negatively regulates SPL transcription factors. We transferred the Cg1 phenotype to other plants by expressing the gene behind constitutive promoters in four different species, including the monocots, Brachypodium and switchgrass, and dicots, Arabidopsis and poplar. All transformants displayed a similar range of phenotypes, including increased biomass from extended leaf production, and increased vegetative branching. Field grown switchgrass transformants showed that overall lignin content was reduced, the ratio of glucans to xylans was increased, and surprisingly, that starch levels were greatly increased. The goals of this project are to control the tissue and temporal expression of Cg1 by using different promoters to drive its expression, elucidate the function of the SPL targets of Cg1 by generating gain and loss of function alleles, and isolate downstream targets of select SPL genes using deep sequencing and chromatin immunoprecipitation. We believe it is possible to control biomass accumulation, cell wall properties, and sugar levels through manipulation of either the Cg1 gene and/or its SPL targets.

  2. In vitro effects of copper nanoparticles on plant pathogens, beneficial microbes and crop plants

    Directory of Open Access Journals (Sweden)

    Susanta Banik

    2017-07-01

    Full Text Available Copper-based chemicals are effectively used as antimicrobials in agriculture. However, with respect to its nanoparticulate form there has been limited number of studies. In this investigation, in vitro tests on effect of copper nanoparticles (CuNPs against plant pathogenic fungi, oomycete, bacteria, beneficial microbes Trichoderma harzianum and Rhizobium spp., and wheat seeds were conducted. Integration of CuNPs with non-nano copper like copper oxychloride (CoC at 50 mg/L concentration each recorded 76% growth inhibition of the oomycete Phytophthora cinnamomi in vitro compared to the control. CuNPs also showed synergistic inhibitory effect with CoC on mycelial growth and sporulation of A. alternata. Pseudomonas syringae was inhibited at 200 mg/L of CuNPs. CuNPs were not significantly biocidal against Rhizobium spp. and Trichoderma harzianum compared to CoC. Evaluation of the effect of CuNP on wheat revealed that rate of germination of wheat seeds was higher in presence of CuNPs and CoC compared to control. Germination vigor index, root length, shoot dry weight and seed metabolic efficiency of wheat were negatively affected. At low concentration, CuNPs promoted the growth of the plant pathogenic fungi Botrytis fabae, Fusarium oxysporum f.sp. ciceris, F.oxysporum f.sp. melonis, Alternaria alternate and P. syringae, and sporulation of T. harzianum. Synergistic effect of CuNPs and CoC in inhibiting P. cinnamomi offers a possibility of developing new fungicide formulation for better control of the oomycetes. Non-biocidal effect of CuNPs against beneficial microbes indicates its potential use in the agri-ecosystem.

  3. Direct derivation of maize plant and crop height from low-cost time-of-flight camera measurements.

    Science.gov (United States)

    Hämmerle, Martin; Höfle, Bernhard

    2016-01-01

    In agriculture, information about the spatial distribution of crop height is valuable for applications such as biomass and yield estimation, or increasing field work efficiency in terms of fertilizing, applying pesticides, irrigation, etc. Established methods for capturing crop height often comprise restrictions in terms of cost and time efficiency, flexibility, and temporal and spatial resolution of measurements. Furthermore, crop height is mostly derived from a measurement of the bare terrain prior to plant growth and measurements of the crop surface when plants are growing, resulting in the need of multiple field campaigns. In our study, we examine a method to derive crop heights directly from data of a plot of full grown maize plants captured in a single field campaign. We assess continuous raster crop height models (CHMs) and individual plant heights derived from data collected with the low-cost 3D camera Microsoft(®) Kinect(®) for Xbox One™ based on a comprehensive comparison to terrestrial laser scanning (TLS) reference data. We examine single measurements captured with the 3D camera and a combination of the single measurements, i.e. a combination of multiple perspectives. The quality of both CHMs, and individual plant heights is improved by combining the measurements. R(2) of CHMs derived from single measurements range from 0.48 to 0.88, combining all measurements leads to an R(2) of 0.89. In case of individual plant heights, an R(2) of 0.98 is achieved for the combined measures (with R(2) = 0.44 for the single measurements). The crop heights derived from the 3D camera measurements comprise an average underestimation of 0.06 m compared to TLS reference values. We recommend the combination of multiple low-cost 3D camera measurements, removal of measurement artefacts, and the inclusion of correction functions to improve the quality of crop height measurements. Operating low-cost 3D cameras under field conditions on agricultural machines or on

  4. Evolution of filamentous plant pathogens: gene exchange across eukaryotic kingdoms.

    Science.gov (United States)

    Richards, Thomas A; Dacks, Joel B; Jenkinson, Joanna M; Thornton, Christopher R; Talbot, Nicholas J

    2006-09-19

    Filamentous fungi and oomycetes are eukaryotic microorganisms that grow by producing networks of thread-like hyphae, which secrete enzymes to break down complex nutrients, such as wood and plant material, and recover the resulting simple sugars and amino acids by osmotrophy. These organisms are extremely similar in both appearance and lifestyle and include some of the most economically important plant pathogens . However, the morphological similarity of fungi and oomycetes is misleading because they represent some of the most distantly related eukaryote evolutionary groupings, and their shared osmotrophic growth habit is interpreted as being the result of convergent evolution . The fungi branch with the animals, whereas the oomycetes branch with photosynthetic algae as part of the Chromalveolata . In this report, we provide strong phylogenetic evidence that multiple horizontal gene transfers (HGT) have occurred from filamentous ascomycete fungi to the distantly related oomycetes. We also present evidence that a subset of the associated gene families was initially the product of prokaryote-to-fungi HGT. The predicted functions of the gene products associated with fungi-to-oomycete HGT suggest that this process has played a significant role in the evolution of the osmotrophic, filamentous lifestyle on two separate branches of the eukaryote tree.

  5. Evolution of 'smoke' induced seed germination in pyroendemic plants

    Science.gov (United States)

    Keeley, J. E.; Pausas, J.G.

    2016-01-01

    Pyroendemics are plants in which seedling germination and successful seedling recruitment are restricted to immediate postfire environments. In many fire-prone ecosystems species cue their germination to immediate postfire conditions. Here we address how species have evolved one very specific mechanism, which is using the signal of combustion products from biomass. This is often termed ‘smoke’ stimulated germination although it was first discovered in studies of charred wood effects on germination of species strictly tied to postfire conditions (pyroendemics). Smoke stimulated germination has been reported from a huge diversity of plant species. The fact that the organic compound karrikin (a product of the degradation of cellulose) is a powerful germination cue in many species has led to the assumption that this compound is the only chemical responsible for smoke-stimulated germination. Here we show that smoke-stimulated germination is a complex trait with different compounds involved. We propose that convergent evolution is a more parsimonious model for smoke stimulated germination, suggesting that this trait evolved multiple times in response to a variety of organic and inorganic chemical triggers in smoke. The convergent model is congruent with the evolution of many other fire-related traits.

  6. Using remote sensing to calculate plant available nitrogen needed by crops on swine factory farm sprayfields in North Carolina

    Science.gov (United States)

    Christenson, Elizabeth; Serre, Marc

    2015-10-01

    North Carolina (NC) is the second largest producer of hogs in the United States with Duplin county, NC having the densest population of hogs in the world. In NC, liquid swine manure is generally stored in open-air lagoons and sprayed onto sprayfields with sprinkler systems to be used as fertilizer for crops. Swine factory farms, termed concentrated animal feeding operations (CAFOs), are regulated by the Department of Environment and Natural Resources (DENR) based on nutrient management plans (NMPs) having balanced plant available nitrogen (PAN). The estimated PAN in liquid manure being sprayed must be less than the estimated PAN needed crops during irrigation. Estimates for PAN needed by crops are dependent on crop and soil types. Objectives of this research were to develop a new, time-efficient method to identify PAN needed by crops on Duplin county sprayfields for years 2010-2014. Using remote sensing data instead of NMP data to identify PAN needed by crops allowed calendar year identification of which crops were grown on sprayfields instead of a five-year range of values. Although permitted data have more detailed crop information than remotely sensed data, identification of PAN needed by crops using remotely sensed data is more time efficient, internally consistent, easily publically accessible, and has the ability to identify annual changes in PAN on sprayfields. Once PAN needed by crops is known, remote sensing can be used to quantify PAN at other spatial scales, such as sub-watershed levels, and can be used to inform targeted water quality monitoring of swine CAFOs.

  7. In vitro plant propagation and crop improvement in Lisianthus (Lisianthus Russelianus Hook.

    Directory of Open Access Journals (Sweden)

    Rodica Pop

    2016-11-01

    Full Text Available Romania assists at the present time to an increase of production crops for ornamental plants and as a consequence an increased demand of planting material. Thus, improvements of the current multiplication methods are sought after. Lisianthus russelianus Hook. (Eustoma grandiflorum Grise. is a relatively new floral crop to the international market, known for beautiful flowers of various colors and for having a long vase life. This study focused on the development of an efficient protocol for rapid regeneration of this species following known basic and applied aspects of lisianthus biotechnology but exploring new potentials. In the course of experiments conducted, for in vitro multiplication there were used nodal segments (1.5 cm with axillary buds from three F1 hybrids ‘Echo Lavender’, ‘Flamenco White’, ‘Mirage Pastel Pink’ that were inoculated on MS basal medium supplemented with 0.50 mg 1-1 TDZ, 1.0 mg 1-1 BAP and 0.50 mg 1-1 AIA. The results show that the medium with BAP was most effective for obtaining the highest shoots number compared to medium containing TDZ. For rooting induction, two different concentrations of auxin IBA 0.5 mg 1-1 and 1.5 mg 1-1 were used simultaneously on MS basal medium. The highest roots number occurred when using 1.5 mg 1-1 IBA. Both the number of shoots and rooting regeneration were dependent on the cultivar. The highest shoots number was achieved for ’Mirage Pastel Pink’ hybrid (6.91 on the medium containing 1.0 mg 1-1 BAP and 0.50 mg 1-1 IAA.

  8. Evaluation of developmental responses of two crop plants exposed to silver and zinc oxide nanoparticles.

    Science.gov (United States)

    Pokhrel, Lok R; Dubey, Brajesh

    2013-05-01

    The increasing applications of different nanomaterials in the myriad of nano-enabled products and their potential for leaching have raised considerable environmental, health and safety (EHS) concerns. As systematic studies investigating potential anomalies in the morphology and anatomy of crop plants are scarce, herein we report on the developmental responses of two agriculturally significant crop plants, maize (Zea mays L.) and cabbage (Brassica oleracea var. capitata L.), upon in vitro exposure to nanoparticles of citrate-coated silver (Citrate-nAg) and zinc oxide (nZnO). Analyses involve histology of the primary root morphology and anatomy using light microscopy, metal biouptake, moisture content, rate of germination, and root elongation. Comparative toxicity profiles of the ionic salts (AgNO3 and ZnSO4) are developed. Notably, we uncover structural changes in maize primary root cells upon exposure to Citrate-nAg, nZnO, AgNO3, and ZnSO4, possibly due to metal biouptake, suggesting potential for functional impairments in the plant growth and development. Citrate-nAg exposure results in lower Ag biouptake compared to AgNO3 treatment in maize. Microscopic evidence reveals 'tunneling-like effect' with nZnO treatment, while exposure to AgNO3 leads to cell erosion in maize root apical meristem. In maize, a significant change in metaxylem count is evident with Citrate-nAg, AgNO3, and ZnSO4 treatment, but not with nZnO treatment (p>0.1). In both maize and cabbage, measures of germination and root elongation reveal lower nanoparticle toxicity compared to free ions. As moisture data do not support osmotically-induced water stress hypothesis for explaining toxicity, we discuss other proximate mechanisms including the potential role of growth hormones and transcription factors. These findings highlight previously overlooked, anatomically significant effects of metal nanoparticles, and recommend considering detailed anatomical investigations in tandem with the standard

  9. Effect of sorghum-sudangrass and velvetbean cover crops on plant-parasitic nematodes associated with potato production in Florida.

    Science.gov (United States)

    Crow, W T; Weingartner, D P; Dickson, D W; McSorley, R

    2001-12-01

    In a 3-year field study, population densities of Belonolaimus longicaudatus and other plant-parasitic nematodes and crop yields were compared between potato (Solanum tuberosum) cropping systems where either sorghum-sudangrass (Sorghum bicolor x S. arundinaceum) or velvetbean (Mucuna pruriens) was grown as a summer cover crop. Population densities of B. longicaudatus, Paratrichodorus minor, Tylenchorhynchus sp., and Mesocriconema sp. increased on sorghum-sudangrass. Population densities of P. minor and Mesocriconema sp. increased on velvetbean. Sorghum-sudangrass increased population densities of B. longicaudatus and Mesocriconema sp. on a subsequent potato crop compared to velvetbean. Potato yields following velvetbean were not greater than following sorghum-sudangrass despite reductions in population densities of B. longicaudatus.

  10. Ecology and evolution of plant-pollinator interactions.

    Science.gov (United States)

    Mitchell, Randall J; Irwin, Rebecca E; Flanagan, Rebecca J; Karron, Jeffrey D

    2009-06-01

    Some of the most exciting advances in pollination biology have resulted from interdisciplinary research combining ecological and evolutionary perspectives. For example, these two approaches have been essential for understanding the functional ecology of floral traits, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant-pollinator interactions. However, as research in these and other areas has progressed, many pollination biologists have become more specialized in their research interests, focusing their attention on either evolutionary or ecological questions. We believe that the continuing vigour of a synthetic and interdisciplinary field like pollination biology depends on renewed connections between ecological and evolutionary approaches. In this Viewpoint paper we highlight the application of ecological and evolutionary approaches to two themes in pollination biology: (1) links between pollinator behaviour and plant mating systems, and (2) generalization and specialization in pollination systems. We also describe how mathematical models and synthetic analyses have broadened our understanding of pollination biology, especially in human-modified landscapes. We conclude with several suggestions that we hope will stimulate future research. This Viewpoint also serves as the introduction to this Special Issue on the Ecology and Evolution of Plant-Pollinator Interactions. These papers provide inspiring examples of the synergy between evolutionary and ecological approaches, and offer glimpses of great accomplishments yet to come.

  11. Integrating Plant Science and Crop Modeling: Assessment of the Impact of Climate Change on Soybean and Maize Production.

    Science.gov (United States)

    Fodor, Nándor; Challinor, Andrew; Droutsas, Ioannis; Ramirez-Villegas, Julian; Zabel, Florian; Koehler, Ann-Kristin; Foyer, Christine H

    2017-11-01

    Increasing global CO2 emissions have profound consequences for plant biology, not least because of direct influences on carbon gain. However, much remains uncertain regarding how our major crops will respond to a future high CO2 world. Crop model inter-comparison studies have identified large uncertainties and biases associated with climate change. The need to quantify uncertainty has drawn the fields of plant molecular physiology, crop breeding and biology, and climate change modeling closer together. Comparing data from different models that have been used to assess the potential climate change impacts on soybean and maize production, future yield losses have been predicted for both major crops. When CO2 fertilization effects are taken into account significant yield gains are predicted for soybean, together with a shift in global production from the Southern to the Northern hemisphere. Maize production is also forecast to shift northwards. However, unless plant breeders are able to produce new hybrids with improved traits, the forecasted yield losses for maize will only be mitigated by agro-management adaptations. In addition, the increasing demands of a growing world population will require larger areas of marginal land to be used for maize and soybean production. We summarize the outputs of crop models, together with mitigation options for decreasing the negative impacts of climate on the global maize and soybean production, providing an overview of projected land-use change as a major determining factor for future global crop production. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.

  12. Evolution of xyloglucan-related genes in green plants

    Directory of Open Access Journals (Sweden)

    Vincentz Michel GA

    2010-11-01

    Full Text Available Abstract Background The cell shape and morphology of plant tissues are intimately related to structural modifications in the primary cell wall that are associated with key processes in the regulation of cell growth and differentiation. The primary cell wall is composed mainly of cellulose immersed in a matrix of hemicellulose, pectin, lignin and some structural proteins. Xyloglucan is a hemicellulose polysaccharide present in the cell walls of all land plants (Embryophyta and is the main hemicellulose in non-graminaceous angiosperms. Results In this work, we used a comparative genomic approach to obtain new insights into the evolution of the xyloglucan-related enzymatic machinery in green plants. Detailed phylogenetic analyses were done for enzymes involved in xyloglucan synthesis (xyloglucan transglycosylase/hydrolase, α-xylosidase, β-galactosidase, β-glucosidase and α-fucosidase and mobilization/degradation (β-(1→4-glucan synthase, α-fucosyltransferases, β-galactosyltransferases and α-xylosyl transferase based on 12 fully sequenced genomes and expressed sequence tags from 29 species of green plants. Evidence from Chlorophyta and Streptophyta green algae indicated that part of the Embryophyta xyloglucan-related machinery evolved in an aquatic environment, before land colonization. Streptophyte algae have at least three enzymes of the xyloglucan machinery: xyloglucan transglycosylase/hydrolase, β-(1→4-glucan synthase from the celullose synthase-like C family and α-xylosidase that is also present in chlorophytes. Interestingly, gymnosperm sequences orthologs to xyloglucan transglycosylase/hydrolases with exclusively hydrolytic activity were also detected, suggesting that such activity must have emerged within the last common ancestor of spermatophytes. There was a positive correlation between the numbers of founder genes within each gene family and the complexity of the plant cell wall. Conclusions Our data support the idea that a

  13. Analysing crop yield and plant quality in an intercropping system using an ecophysiological model for interplant competition

    NARCIS (Netherlands)

    Baumann, D.T.; Bastiaans, L.; Goudriaan, J.; Laar, van H.H.; Kropff, M.J.

    2002-01-01

    An eco-physiological model was used to improve understanding of interplant competition based on physiological, morphological and phenological processes. The model was parameterised based on characteristics of the plants in monocultures and its performance was evaluated for the crop mixtures using

  14. Soil Organic Matter Quality of an Oxisol Affected by Plant Residues and Crop Sequence under No-Tillage

    Science.gov (United States)

    Cora, Jose; Marcelo, Adolfo

    2013-04-01

    Plant residues are considered the primarily resource for soil organic matter (SOM) formation and the amounts and properties of plant litter are important controlling factors for the SOM quality. We determined the amounts, quality and decomposition rate of plant residues and the effects of summer and winter crop sequences on soil organic C (TOC) content, both particulate organic C (POC) and mineral-associated organic C (MOC) pools and humic substances in a Brazilian Rhodic Eutrudox soil under a no-tillage system. The organic C analysis in specifics pools used in this study was effective and should be adopted in tropical climates to evaluate the soil quality and the sustainability of various cropping systems. Continuous growth of soybean (Glycine max L. Merrill) on summer provided higher contents of soil POC and continuous growth of maize (Zea mays L.) provided higher soil humic acid and MOC contents. Summer soybean-maize rotation provided the higher plant diversity, which likely improved the soil microbial activity and the soil organic C consumption. The winter sunn hemp (Crotalaria juncea L.), pigeon pea (Cajanus cajan (L.) Millsp), oilseed radish (Raphanus sativus L.) and pearl millet (Pennisetum americanum (L.) Leeke) enhanced the soil MOC, a finding that is attributable to the higher N content of the crop residue. Sunn hemp and pigeon pea provided the higher soil POC content. Sunn hemp showed better performance and positive effects on the SOM quality, making it a suitable winter crop choice for tropical conditions with a warm and dry winter.

  15. Effect of some detergents, humate, and composition of seedbed on crop of tomato plants in a hydroponic culture

    Science.gov (United States)

    Guminka, A. Z.; Gracz-Nalepka, M.; Lukasiewicz, B.; Sobolewicz, E.; Turkiewicz, I. T.

    1978-01-01

    It is established that single detergent doses distinctly stimulate vegetative development of plants in the initial stage when humates are available. When detergents are applied every four weeks in a hydroponic culture, in which the seedbed does not contain active humates, the crop is reduced by 50%. This adverse effect does not occur when the seedbed is a mixture of brown coal and peat.

  16. Production characteristics of lettuce Lactuca sativa L. in the frame of the first crop tests in the Higher Plant Chamber integrated into the MELiSSA Pilot Plant

    Science.gov (United States)

    Tikhomirova, Natalia; Lawson, Jamie; Stasiak, Michael; Dixon, Mike; Paille, Christel; Peiro, Enrique; Fossen, Arnaud; Godia, Francesc

    Micro-Ecological Life Support System Alternative (MELiSSA) is an artificial closed ecosystem that is considered a tool for the development of a bioregenerative life support system for manned space missions. One of the five compartments of MELiSSA loop -Higher Plant Chamber was recently integrated into the MELiSSA Pilot Plant facility at Universitat Aut`noma deo Barcelona. The main contributions expected by integration of this photosynthetic compartment are oxygen, water, vegetable food production and CO2 consumption. Production characteristics of Lactuca sativa L., as a MELiSSA candidate crop, were investigated in this work in the first crop experiments in the MELiSSA Pilot Plant facility. The plants were grown in batch culture and totaled 100 plants with a growing area 5 m long and 1 m wide in a sealed controlled environment. Several replicates of the experiments were carried out with varying duration. It was shown that after 46 days of lettuce cultivation dry edible biomass averaged 27, 2 g per plant. However accumulation of oxygen in the chamber, which required purging of the chamber, and decrease in the food value of the plants was observed. Reducing the duration of the tests allowed uninterrupted test without opening the system and also allowed estimation of the crop's carbon balance. Results of productivity, tissue composition, nutrient uptake and canopy photosynthesis of lettuce regardless of test duration are discussed in the paper.

  17. Chemical Processing of Non-Crop Plants for Jet Fuel Blends Production

    Science.gov (United States)

    Kulis, M. J.; Hepp, A. F.; McDowell, M.; Ribita, D.

    2009-01-01

    The use of Biofuels has been gaining in popularity over the past few years due to their ability to reduce the dependence on fossil fuels. Biofuels as a renewable energy source can be a viable option for sustaining long-term energy needs if they are managed efficiently. We describe our initial efforts to exploit algae, halophytes and other non-crop plants to produce synthetics for fuel blends that can potentially be used as fuels for aviation and non-aerospace applications. Our efforts have been dedicated to crafting efficient extraction and refining processes in order to extract constituents from the plant materials with the ultimate goal of determining the feasibility of producing biomass-based jet fuel from the refined extract. Two extraction methods have been developed based on communition processes, and liquid-solid extraction techniques. Refining procedures such as chlorophyll removal and transesterification of triglycerides have been performed. Gas chromatography in tandem with mass spectroscopy is currently being utilized in order to qualitatively determine the individual components of the refined extract. We also briefly discuss and compare alternative methods to extract fuel-blending agents from alternative biofuels sources.

  18. Camelina as a sustainable oilseed crop: contributions of plant breeding and genetic engineering.

    Science.gov (United States)

    Vollmann, Johann; Eynck, Christina

    2015-04-01

    Camelina is an underutilized Brassicaceae oilseed plant with a considerable agronomic potential for biofuel and vegetable oil production in temperate regions. In contrast to most Brassicaceae, camelina is resistant to alternaria black spot and other diseases and pests. Sequencing of the camelina genome revealed an undifferentiated allohexaploid genome with a comparatively large number of genes and low percentage of repetitive DNA. As there is a close relationship between camelina and the genetic model plant Arabidopsis, this review aims at exploring the potential of translating basic Arabidopsis results into a camelina oilseed crop for food and non-food applications. Recently, Arabidopsis genes for drought resistance or increased photosynthesis and overall productivity have successfully been expressed in camelina. In addition, gene constructs affecting lipid metabolism pathways have been engineered into camelina for synthesizing either long-chain polyunsaturated fatty acids, hydroxy fatty acids or high-oleic oils in particular camelina strains, which is of great interest in human food, industrial or biofuel applications, respectively. These results confirm the potential of camelina to serve as a biotechnology platform in biorefinery applications thus justifying further investment in breeding and genetic research for combining agronomic potential, unique oil quality features and biosafety into an agricultural production system. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A review of the use of engineered nanomaterials to suppress plant disease and enhance crop yield

    Energy Technology Data Exchange (ETDEWEB)

    Servin, Alia; Elmer, Wade; Mukherjee, Arnab; Torre-Roche, Roberto De la [The Connecticut Agricultural Experiment Station (United States); Hamdi, Helmi [University of Carthage, Water Research and Technology Center (Tunisia); White, Jason C., E-mail: jason.white@ct.gov [The Connecticut Agricultural Experiment Station (United States); Bindraban, Prem; Dimkpa, Christian [Virtual Fertilizer Research Center (United States)

    2015-02-15

    Nanotechnology has the potential to play a critical role in global food production, food security, and food safety. The applications of nanotechnology in agriculture include fertilizers to increase plant growth and yield, pesticides for pest and disease management, and sensors for monitoring soil quality and plant health. Over the past decade, a number of patents and products incorporating nanomaterials into agricultural practices (e.g., nanopesticides, nanofertilizers, and nanosensors) have been developed. The collective goal of all of these approaches is to enhance the efficiency and sustainability of agricultural practices by requiring less input and generating less waste than conventional products and approaches. This review evaluates the current literature on the use of nanoscale nutrients (metals, metal oxides, carbon) to suppress crop disease and subsequently enhance growth and yield. Notably, this enhanced yield may not only be directly linked to the reduced presence of pathogenic organisms, but also to the potential nutritional value of the nanoparticles themselves, especially for the essential micronutrients necessary for host defense. We also posit that these positive effects are likely a result of the greater availability of the nutrients in the “nano” form. Last, we offer comments on the current regulatory perspective for such applications.

  20. A review of the use of engineered nanomaterials to suppress plant disease and enhance crop yield

    Science.gov (United States)

    Servin, Alia; Elmer, Wade; Mukherjee, Arnab; De la Torre-Roche, Roberto; Hamdi, Helmi; White, Jason C.; Bindraban, Prem; Dimkpa, Christian

    2015-02-01

    Nanotechnology has the potential to play a critical role in global food production, food security, and food safety. The applications of nanotechnology in agriculture include fertilizers to increase plant growth and yield, pesticides for pest and disease management, and sensors for monitoring soil quality and plant health. Over the past decade, a number of patents and products incorporating nanomaterials into agricultural practices (e.g., nanopesticides, nanofertilizers, and nanosensors) have been developed. The collective goal of all of these approaches is to enhance the efficiency and sustainability of agricultural practices by requiring less input and generating less waste than conventional products and approaches. This review evaluates the current literature on the use of nanoscale nutrients (metals, metal oxides, carbon) to suppress crop disease and subsequently enhance growth and yield. Notably, this enhanced yield may not only be directly linked to the reduced presence of pathogenic organisms, but also to the potential nutritional value of the nanoparticles themselves, especially for the essential micronutrients necessary for host defense. We also posit that these positive effects are likely a result of the greater availability of the nutrients in the "nano" form. Last, we offer comments on the current regulatory perspective for such applications.

  1. Ecogeography and utility to plant breeding of the crop wild relatives of sunflower (Helianthus annuus L.)

    NARCIS (Netherlands)

    Kantar, M.B.; Sosa, C.C.; Khoury, C.K.; Castaneda-Alvarez, N.P.; Achicanoy, H.A.; Bernau, V.; Kane, N.C.; Marek, L.; Seiler, G.; Rieseberg, L.H.

    2015-01-01

    Crop wild relatives (CWR) are a rich source of genetic diversity for crop improvement. Combining ecogeographic and phylogenetic techniques can inform both conservation and breeding. Geographic occurrence, bioclimatic, and biophysical data were used to predict species distributions, range overlap and

  2. The Effect of Plant Cultivar, Growth Media, Harvest Method and Post Harvest Treatment on the Microbiology of Edible Crops

    Science.gov (United States)

    Hummerick, Mary P.; Gates, Justin R.; Nguyen, Bao-Thang; Massa, Gioia D.; Wheeler, Raymond M.

    2011-01-01

    Systems for the growth of crops in closed environments are being developed and tested for potential use in space applications to provide a source of fresh food. Plant growth conditions, growth media composition and harvest methods can have an effect on the microbial population of the plant, and therefore should be considered along with the optimization of plant growth and harvest yields to ensure a safe and palatable food crop. This work examines the effect of plant cultivar, growth media, and harvest method on plant microbial populations. Twelve varieties of leafy greens and herbs were grown on a mixture of Fafard #2 and Arcillite in the pillow root containment system currently being considered for the VEGGIE plant growth unit developed by Orbitec. In addition, ,Sierra and Outredgeous lettuce varieties were grown in three different mixtures (Fafard #2, Ardllite, and Perlite/Vermiculite). The plants were analyzed for microbial density. Two harvest methods, "cut and come again" (CACA) and terminal harvest were also compared. In one set ofexpe'riments red leaf lettuce and mizuna were grown in pots in a Biomass Production System for education. Plants were harvested every two weeks by either method. Another set of experiments was performed using the rooting pillows to grow 5 varieties of leafy greens and cut harvesting at different intervals. Radishes were harvested and replanted at two-week intervals. Results indicate up to a 3 IOglO difference in microbial counts between some varieties of plants. Rooting medium resulted in an approximately 2 IOglO lower count in the lettuce grown in arscillite then those grown in the other mixtures. Harvest method and frequency had less impact on microbial counts only showing a significant increase in one variety of plant. Post harvest methods to decrease the bacterial counts on edible crops were investigated in these and other experiments. The effectiveness of PRO-SAN and UV-C radiation is compared.

  3. Evolution of Soil Biochemical Parameters in Rainfed Crops: Effect of Organic and Mineral Fertilization

    Directory of Open Access Journals (Sweden)

    Marta M. Moreno

    2012-01-01

    Full Text Available In organic farming, crop fertilization is largely based on the decomposition of organic matter and biological fixation of nutrients. It is therefore necessary to develop studies conducted to know and understand the soil biological processes for the natural nutrient supplies. The effect of three fertilizer managements (chemical with synthetic fertilizers, organic with 2500 kg compost ha−1, and no fertilizer in a rainfed crop rotation (durum wheat-fallow-barley-vetch as green manure on different soil biochemical parameters in semi-arid conditions was investigated. Soil organic matter, microbial biomass carbon, organic matter mineralization, CO2 production-to-ATP ratio, and NO3-N content were analysed. Fertilization was only applied to cereals. The results showed the scarce effect of the organic fertilization on soil quality, which resulted more dependent on weather conditions. Only soil organic matter and NO3-N were affected by fertilization (significantly higher in the inorganic treatment, 1.28 g 100 g−1 and 17.3 ppm, resp.. Soil organic matter was maintained throughout the study period by the inclusion of a legume in the cropping system and the burying of crop residues. In fallow, soil microbial biomass carbon increased considerably (816 ng g−1, and NO3-N at the end of this period was around 35 ppm, equivalent to 100 kg N ha−1.

  4. Recent evolution of China's virtual water trade: analysis of selected crops and considerations for policy

    Science.gov (United States)

    Shi, J.; Liu, J.; Pinter, L.

    2014-04-01

    China has dramatically increased its virtual water import over recent years. Many studies have focused on the quantity of traded virtual water, but very few go into analysing geographic distribution and the properties of China's virtual water trade network. This paper provides a calculation and analysis of the crop-related virtual water trade network of China based on 27 major primary crops between 1986 and 2009. The results show that China is a net importer of virtual water from water-abundant areas of North America and South America, and a net virtual water exporter to water-stressed areas of Asia, Africa, and Europe. Virtual water import is far larger than virtual water export, and in both import and export a small number of trade partners control the supply chain. Grain crops are the major contributors to virtual water trade, and among grain crops, soybeans, mostly imported from the US, Brazil and Argentina, are the most significant. In order to mitigate water scarcity and secure the food supply, virtual water should actively be incorporated into national water management strategies. And the sources of virtual water import need to be further diversified to reduce supply chain risks and increase resilience.

  5. Effects of cover crop termination and cotton planting methods on cotton production in conservation systems

    Science.gov (United States)

    In conservation agriculture, cover crops are utilized to improve soil properties and to enhance cash crop growth. One important part of cover crop management is termination. With smaller profit margins and constraints on time and labor, producers are looking for ways to reduce time and labor require...

  6. Mulching as a countermeasure for crop contamination within the 30 km zone of Chernobyl Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Yera, T.S.; Vallejo, R.; Tent, J.; Rauret, G. [Univ. de Barcelona (Spain); Omelyanenko, N.; Ivanov, Y. [Ukrainian Inst. of Agricultural Radiology, Kiev (Ukraine)

    1999-03-15

    The effect of mulch soil cover on crop contamination by {sup 137}Cs was studied within the 30 km zone of Chernobyl Nuclear Power Plant. Experiments were performed with oats (Avena sativa) over a three year period. In 1992 soil surface was covered by a plastic net. In 1993 two straw mulch treatments were applied at a dose rate of 200 g m{sup {minus}2} using {sup 137}Cs contaminated and clean straw, respectively. A similar mulch treatment was applied in 1994, and two mulch doses of clean straw were tested. Protection of the soil with a plastic net significantly increased crop yield and reduced crop contamination. When clean straw was used as a mulch layer, a significant decrease of about 30--40% in {sup 137}Cs activity concentration was observed. Mulching with {sup 137}Cs contaminated straw did not reduce crop contamination, probably due to an increase in soil available {sup 137}Cs released from the contaminated mulch. Mulching has been shown to be an effective treatment both for reducing {sup 137}Cs plant contamination and improving crop yield. Therefore, it can be considered as a potential countermeasure in a post-accident situation.

  7. Population dynamics of plant nematodes in cultivated soil: effect of summer cover crops in newly cleared land.

    Science.gov (United States)

    Brodie, B B; Good, J M; Jaworski, C A

    1970-07-01

    Five nematode species were studied for ability to develop on seven summer cover crops in rotation with tomato transplants grown every third year. Increase of Tylenchorhynchus claytoni, Trichodorus christiei, Pratylenchus brachyurus, Helicotylenchus dihystera, and Xiphinema americanum in newly cleared soil varied with different cover crops. No substantial nematode population increases occurred until the third summer of crop growth. All species except X. americanum and H. dihystera developed best on sudangrass and millet. Crotalaria caused substantial increase of H. dihystera and P. brachyurus but suppressed the other species. Marigold suppressed all species except X. americanum which increased substantially on marigold during the 5th year. Cotton favored rapid increase of T. christiei, and moderate increases of all species except T. claytoni which was suppressed. Beggarweed favored moderate increases of T. christiei and H. dihystera but suppressed the other species. Hairy indigo favored rapid increase of H. dihystera, moderate increases of T. christiei and X. americanum, and suppressed the other species. Number of marketable transplants was reduced after 2 years of sudangrass and cotton; these crops favored increases of T. christiei and T. claytoni. The better cover crops prevented increases of most plant parasitic nematodes in land cropped to tomato, a suitable host.

  8. Energy crops for biogas plants. Saxony-Anhalt; Energiepflanzen fuer Biogasanlagen. Sachsen-Anhalt

    Energy Technology Data Exchange (ETDEWEB)

    Boese, L.; Buttlar, C. von; Boettcher, K. (and others)

    2012-07-15

    For agriculturists in Saxony-Anhalt (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  9. Energy crops for biogas plants. Baden-Wuerttemberg; Energiepflanzen fuer Biogasanlagen. Baden-Wuerttemberg

    Energy Technology Data Exchange (ETDEWEB)

    Butz, A.; Heiermann, M.; Herrmann, C. [and others

    2013-05-01

    For agriculturists in Baden-Wuerttemberg (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  10. Energy crops for biogas plants. Mecklenburg-Western Pomerania; Energiepflanzen fuer Biogasanlagen. Mecklenburg-Vorpommern

    Energy Technology Data Exchange (ETDEWEB)

    Aurbacher, J.; Bull, I.; Formowitz, B. (and others)

    2012-06-15

    For agriculturists in Mecklenburg-Western Pomerania (Federal Republic of Germany), the brochure under consideration provides recommendations on alternative crop rotation systems. With the help of these alternative cultivation systems, crop rotation with high yields in combination with high diversity, diversification and sustainability can be realized. Subsequently to the presentation of energy crops for the production of biogas, recommendations for the design of crop rotation are given. Other chapters of this booklet deal with ensilage and gas yields as well as the economics of energy crop cultivation.

  11. Cascade Cropping System with Horticultural and Ornamental Plants under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Pedro García-Caparrós

    2018-01-01

    Full Text Available The blending of drainage with water of low electrical conductivity and the sequential reuse of the drainage water are innovative technologies to manage salts in agricultural drainage. Plants of Cucumis melo were grown in coir grow bags, and Rosmarinus officinalis and Cacti spp. were grown in pots with a mixture of sphagnum peat-moss and perlite. In order to assess the effect and evolution over time of these water treatments on plant growth and water management and removal of nutrients, three water treatments were applied over a period of eight weeks. These were: (1 standard nutrient solution; (2 blended water treatment (drainage water blended with water of low electrical conductivity (EC and (3 sequential reuse of drainage water treatment. During the experimental growing period, samples of water supplies and drainages generated in each water treatment were collected weekly and from these data water volume and nutrient loads were calculated. At the end of the experiment, leaf fresh weight of rosemary plants decreased under the fertigation with the blended and sequential reuse water treatments. Nevertheless, the application of blended and sequentially reused water allowed for the saving of significant amounts of water and nutrients in comparison to the standard nutrient solution treatment. Considering these advantages, we strongly recommend the setting-up of these water treatments in areas with water scarcity such as in the Mediterranean Basin.

  12. Biofertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity

    Science.gov (United States)

    2014-01-01

    Current soil management strategies are mainly dependent on inorganic chemical-based fertilizers, which caused a serious threat to human health and environment. The exploitation of beneficial microbes as a biofertilizer has become paramount importance in agriculture sector for their potential role in food safety and sustainable crop production. The eco-friendly approaches inspire a wide range of application of plant growth promoting rhizobacteria (PGPRs), endo- and ectomycorrhizal fungi, cyanobacteria and many other useful microscopic organisms led to improved nutrient uptake, plant growth and plant tolerance to abiotic and biotic stress. The present review highlighted biofertilizers mediated crops functional traits such as plant growth and productivity, nutrient profile, plant defense and protection with special emphasis to its function to trigger various growth- and defense-related genes in signaling network of cellular pathways to cause cellular response and thereby crop improvement. The knowledge gained from the literature appraised herein will help us to understand the physiological bases of biofertlizers towards sustainable agriculture in reducing problems associated with the use of chemicals fertilizers. PMID:24885352

  13. Biofertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity.

    Science.gov (United States)

    Bhardwaj, Deepak; Ansari, Mohammad Wahid; Sahoo, Ranjan Kumar; Tuteja, Narendra

    2014-05-08

    Current soil management strategies are mainly dependent on inorganic chemical-based fertilizers, which caused a serious threat to human health and environment. The exploitation of beneficial microbes as a biofertilizer has become paramount importance in agriculture sector for their potential role in food safety and sustainable crop production. The eco-friendly approaches inspire a wide range of application of plant growth promoting rhizobacteria (PGPRs), endo- and ectomycorrhizal fungi, cyanobacteria and many other useful microscopic organisms led to improved nutrient uptake, plant growth and plant tolerance to abiotic and biotic stress. The present review highlighted biofertilizers mediated crops functional traits such as plant growth and productivity, nutrient profile, plant defense and protection with special emphasis to its function to trigger various growth- and defense-related genes in signaling network of cellular pathways to cause cellular response and thereby crop improvement. The knowledge gained from the literature appraised herein will help us to understand the physiological bases of biofertlizers towards sustainable agriculture in reducing problems associated with the use of chemicals fertilizers.

  14. Evaluation of developmental responses of two crop plants exposed to silver and zinc oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pokhrel, Lok R. [Department of Environmental Health, College of Public Health, East Tennessee State University, Johnson City, TN 37614–1700 (United States); Dubey, Brajesh, E-mail: bdubey@uoguelph.ca [Environmental Engineering, School of Engineering, University of Guelph, 50 Stone Road East, Guelph, Ontario (Canada)

    2013-05-01

    The increasing applications of different nanomaterials in the myriad of nano-enabled products and their potential for leaching have raised considerable environmental, health and safety (EHS) concerns. As systematic studies investigating potential anomalies in the morphology and anatomy of crop plants are scarce, herein we report on the developmental responses of two agriculturally significant crop plants, maize (Zea mays L.) and cabbage (Brassica oleracea var. capitata L.), upon in vitro exposure to nanoparticles of citrate-coated silver (Citrate–nAg) and zinc oxide (nZnO). Analyses involve histology of the primary root morphology and anatomy using light microscopy, metal biouptake, moisture content, rate of germination, and root elongation. Comparative toxicity profiles of the ionic salts (AgNO{sub 3} and ZnSO{sub 4}) are developed. Notably, we uncover structural changes in maize primary root cells upon exposure to Citrate–nAg, nZnO, AgNO{sub 3}, and ZnSO{sub 4}, possibly due to metal biouptake, suggesting potential for functional impairments in the plant growth and development. Citrate–nAg exposure results in lower Ag biouptake compared to AgNO{sub 3} treatment in maize. Microscopic evidence reveals ‘tunneling-like effect’ with nZnO treatment, while exposure to AgNO{sub 3} leads to cell erosion in maize root apical meristem. In maize, a significant change in metaxylem count is evident with Citrate–nAg, AgNO{sub 3}, and ZnSO{sub 4} treatment, but not with nZnO treatment (p > 0.1). In both maize and cabbage, measures of germination and root elongation reveal lower nanoparticle toxicity compared to free ions. As moisture data do not support osmotically-induced water stress hypothesis for explaining toxicity, we discuss other proximate mechanisms including the potential role of growth hormones and transcription factors. These findings highlight previously overlooked, anatomically significant effects of metal nanoparticles, and recommend considering

  15. Communicative interactions involving plants: information, evolution, and ecology.

    Science.gov (United States)

    Mescher, Mark C; Pearse, Ian S

    2016-08-01

    The role of information obtained via sensory cues and signals in mediating the interactions of organisms with their biotic and abiotic environments has been a major focus of work on sensory and behavioral ecology. Information-mediated interactions also have important implications for broader ecological patterns emerging at the community and ecosystem levels that are only now beginning to be explored. Given the extent to which plants dominate the sensory landscapes of terrestrial ecosystems, information-mediated interactions involving plants should be a major focus of efforts to elucidate these broader patterns. Here we explore how such efforts might be enhanced by a clear understanding of information itself-a central and potentially unifying concept in biology that has nevertheless been the subject of considerable confusion-and of its relationship to adaptive evolution and ecology. We suggest that information-mediated interactions should be a key focus of efforts to more fully integrate evolutionary biology and ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Physiological response and sulfur metabolism of the V. dahliae-infected tomato plants in tomato/potato onion companion cropping

    Science.gov (United States)

    Fu, Xuepeng; Li, Chunxia; Zhou, Xingang; Liu, Shouwei; Wu, Fengzhi

    2016-01-01

    Companion cropping with potato onions (Allium cepa var. agrogatum Don.) can enhance the disease resistance of tomato plants (Solanum lycopersicum) to Verticillium dahliae infection by increasing the expressions of genes related to disease resistance. However, it is not clear how tomato plants physiologically respond to V. dahliae infection and what roles sulfur plays in the disease-resistance. Pot experiments were performed to examine changes in the physiology and sulfur metabolism of tomato roots infected by V. dahliae under the companion cropping (tomato/potato onion). The results showed that the companion cropping increased the content of total phenol, lignin and glutathione and increased the activities of peroxidase, polyphenol oxidase and phenylalanine ammonia lyase in the roots of tomato plants. RNA-seq analysis showed that the expressions of genes involved in sulfur uptake and assimilation, and the formation of sulfur-containing defense compounds (SDCs) were up-regulated in the V. dahlia-infected tomatoes in the companion cropping. In addition, the interactions among tomato, potato onion and V. dahliae induced the expression of the high- affinity sulfate transporter gene in the tomato roots. These results suggest that sulfur may play important roles in tomato disease resistance against V. dahliae. PMID:27808257

  17. Hydro-gelified and film forming formulation of microbial plant biostimulants for crop residues treatment on conservation agriculture systems

    Directory of Open Access Journals (Sweden)

    Oancea F.

    2016-05-01

    Full Text Available Microbial plant biostimulants represent one of the solutions for the negative impacts associated with high residues agricultural systems. We developed a hydro-gelified and film forming formulation, which we used for in situ formation of a bio-composite mulch, by treatment on crop residues. Into this hydro-gelified and film forming composition we included microbial biostimulants strains, Trichoderma asperellum T36 and Brevibacillus parabrevis B50. We tested the effects of application of such microbial plant biostimulant formulation on polyamines and ortosilicic acid release from a mixture of hairy vetch and corn residues, on controlled conditions. We evaluated the influence of crop residues treatment with our formulation on crop yield and soil characteristics - water stable aggregates, glomalin related soil proteins. The results demonstrate that treatments on crop residues with our formulation of microbial plant biostimulants compensates some disadvantages of high residues conservation agriculture, enhancing its effects on soil aggregate stability, due to the promotion of glomalin related soil proteins formation.

  18. Physiological response and sulfur metabolism of the V. dahliae-infected tomato plants in tomato/potato onion companion cropping.

    Science.gov (United States)

    Fu, Xuepeng; Li, Chunxia; Zhou, Xingang; Liu, Shouwei; Wu, Fengzhi

    2016-11-03

    Companion cropping with potato onions (Allium cepa var. agrogatum Don.) can enhance the disease resistance of tomato plants (Solanum lycopersicum) to Verticillium dahliae infection by increasing the expressions of genes related to disease resistance. However, it is not clear how tomato plants physiologically respond to V. dahliae infection and what roles sulfur plays in the disease-resistance. Pot experiments were performed to examine changes in the physiology and sulfur metabolism of tomato roots infected by V. dahliae under the companion cropping (tomato/potato onion). The results showed that the companion cropping increased the content of total phenol, lignin and glutathione and increased the activities of peroxidase, polyphenol oxidase and phenylalanine ammonia lyase in the roots of tomato plants. RNA-seq analysis showed that the expressions of genes involved in sulfur uptake and assimilation, and the formation of sulfur-containing defense compounds (SDCs) were up-regulated in the V. dahlia-infected tomatoes in the companion cropping. In addition, the interactions among tomato, potato onion and V. dahliae induced the expression of the high- affinity sulfate transporter gene in the tomato roots. These results suggest that sulfur may play important roles in tomato disease resistance against V. dahliae.

  19. Environmental stress-mediated changes in transcriptional and translational regulation of protein synthesis in crop plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The research described in this final report focused on the influence of stress agents on protein synthesis in crop plants (primarily soybean). Investigations into the `heat shock` (HS) stress mediated changes in transcriptional and translocational regulation of protein synthesis coupled with studies on anaerobic water deficit and other stress mediated alterations in protein synthesis in plants provided the basis of the research. Understanding of the HS gene expression and function(s) of the HSPs may clarify regulatory mechanisms operative in development. Since the reproductive systems of plants if often very temperature sensitive, it may be that the system could be manipulated to provide greater thermotolerance.

  20. Evolution of specifier proteins in glucosinolate-containing plants

    Directory of Open Access Journals (Sweden)

    Kuchernig Jennifer C

    2012-07-01

    independently in different Brassicaceae lineages as suggested by the phylogeny. The ability to form non-isothiocyanate products by specifier protein activity may provide plants with a selective advantage. The evolution of specifier proteins in the Brassicaceae demonstrates the plasticity of secondary metabolism within an activated plant defense system.

  1. The evolution of crop cultivation and paleoenvironment in the Longji Terraces, southern China: Organic geochemical evidence from paleosols.

    Science.gov (United States)

    Jiang, Yongjian; Li, Shijie; Chen, Wei; Cai, Desuo; Liu, Yan

    2017-11-01

    The Longji ancient agricultural terraces in the Longji Mountain area (Guilin, southern China), which still remain in use, are famous for their magnificent terraced landscape with a mix of ecosystem and human inhabitation. Previous research has revealed the genesis and preliminary paleoenvironmental record of the agricultural terraces, but little is known about variations in crop cultivation over time. In this study, organic geochemical analyses and radiocarbon dating of an aggradational cultivated soil from a terrace profile were used to explore crop type variation and relevant paleoenvironmental change during the period of cultivation on the Longji Terraces. Hydroponic farming with rice (C 3 ) planting has been the dominant cultivation mode since the initial construction of the terraces. Warm-dry climate contributed to the growth of drought-tolerant crop (C 4 ) cultivation in the late 15th century. Temperature deterioration during the Little Ice Age had a negative impact on dry and hydroponic farming activities from the late 15th century to the late 19th century, while climate warming after the Little Ice Age promoted the redevelopment of hydroponic farming. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Prioritizing stream types according to their potential risk to receive crop plant material--A GIS-based procedure to assist in the risk assessment of genetically modified crops and systemic insecticide residues.

    Science.gov (United States)

    Bundschuh, Rebecca; Kuhn, Ulrike; Bundschuh, Mirco; Naegele, Caroline; Elsaesser, David; Schlechtriemen, Ulrich; Oehen, Bernadette; Hilbeck, Angelika; Otto, Mathias; Schulz, Ralf; Hofmann, Frieder

    2016-03-15

    Crop plant residues may enter aquatic ecosystems via wind deposition or surface runoff. In the case of genetically modified crops or crops treated with systemic pesticides, these materials may contain insecticidal Bt toxins or pesticides that potentially affect aquatic life. However, the particular exposure pattern of aquatic ecosystems (i.e., via plant material) is not properly reflected in current risk assessment schemes, which primarily focus on waterborne toxicity and not on plant material as the route of uptake. To assist in risk assessment, the present study proposes a prioritization procedure of stream types based on the freshwater network and crop-specific cultivation data using maize in Germany as a model system. To identify stream types with a high probability of receiving crop materials, we developed a formalized, criteria-based and thus transparent procedure that considers the exposure-related parameters, ecological status--an estimate of the diversity and potential vulnerability of local communities towards anthropogenic stress--and availability of uncontaminated reference sections. By applying the procedure to maize, ten stream types out of 38 are expected to be the most relevant if the ecological effects from plant-incorporated pesticides need to be evaluated. This information is an important first step to identifying habitats within these stream types with a high probability of receiving crop plant material at a more local scale, including accumulation areas. Moreover, the prioritization procedure developed in the present study may support the selection of aquatic species for ecotoxicological testing based on their probability of occurrence in stream types having a higher chance of exposure. Finally, this procedure can be adapted to any geographical region or crop of interest and is, therefore, a valuable tool for a site-specific risk assessment of crop plants carrying systemic pesticides or novel proteins, such as insecticidal Bt toxins, expressed

  3. Rare earth elements (REEs): effects on germination and growth of selected crop and native plant species.

    Science.gov (United States)

    Thomas, Philippe J; Carpenter, David; Boutin, Céline; Allison, Jane E

    2014-02-01

    The phytotoxicity of rare earth elements (REEs) is still poorly understood. The exposure-response relationships of three native Canadian plant species (common milkweed, Asclepias syriaca L., showy ticktrefoil, Desmodium canadense (L.) DC. and switchgrass, Panicum virgatum L.) and two commonly used crop species (radish, Raphanus sativus L., and tomato, Solanum lycopersicum L.) to the REEs lanthanum (La), yttrium (Y) and cerium (Ce) were tested. In separate experiments, seven to eight doses of each element were added to the soil prior to sowing seeds. Effects of REE dose on germination were established through measures of total percent germination and speed of germination; effects on growth were established through determination of above ground biomass. Ce was also tested at two pH levels and plant tissue analysis was conducted on pooled samples. Effects on germination were mostly observed with Ce at low pH. However, effects on growth were more pronounced, with detectable inhibition concentrations causing 10% and 25% reductions in biomass for the two native forb species (A. syriaca and D. canadense) with all REEs and on all species tested with Ce in both soil pH treatments. Concentration of Ce in aboveground biomass was lower than root Ce content, and followed the dose-response trend. From values measured in natural soils around the world, our results continue to support the notion that REEs are of limited toxicity and not considered extremely hazardous to the environment. However, in areas where REE contamination is likely, the slow accumulation of these elements in the environment could become problematic. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. The Importance of the Microbial N Cycle in Soil for Crop Plant Nutrition.

    Science.gov (United States)

    Hirsch, Penny R; Mauchline, Tim H

    2015-01-01

    Nitrogen is crucial for living cells, and prior to the introduction of mineral N fertilizer, fixation of atmospheric N2 by diverse prokaryotes was the primary source of N in all ecosystems. Microorganisms drive the N cycle starting with N2 fixation to ammonia, through nitrification in which ammonia is oxidized to nitrate and denitrification where nitrate is reduced to N2 to complete the cycle, or partially reduced to generate the greenhouse gas nitrous oxide. Traditionally, agriculture has relied on rotations that exploited N fixed by symbiotic rhizobia in leguminous plants, and recycled wastes and manures that microbial activity mineralized to release ammonia or nitrate. Mineral N fertilizer provided by the Haber-Bosch process has become essential for modern agriculture to increase crop yields and replace N removed from the system at harvest. However, with the increasing global population and problems caused by unintended N wastage and pollution, more sustainable ways of managing the N cycle in soil and utilizing biological N2 fixation have become imperative. This review describes the biological N cycle and details the steps and organisms involved. The effects of various agricultural practices that exploit fixation, retard nitrification, and reduce denitrification are presented, together with strategies that minimize inorganic fertilizer applications and curtail losses. The development and implementation of new technologies together with rediscovering traditional practices are discussed to speculate how the grand challenge of feeding the world sustainably can be met. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Accelerated Generation of Selfed Pure Line Plants for Gene Identification and Crop Breeding

    Directory of Open Access Journals (Sweden)

    Guijun Yan

    2017-10-01

    Full Text Available Production of pure lines is an important step in biological studies and breeding of many crop plants. The major types of pure lines for biological studies and breeding include doubled haploid (DH lines, recombinant inbred lines (RILs, and near isogenic lines (NILs. DH lines can be produced through microspore and megaspore culture followed by chromosome doubling while RILs and NILs can be produced through introgressions or repeated selfing of hybrids. DH approach was developed as a quicker method than conventional method to produce pure lines. However, its drawbacks of genotype-dependency and only a single chance of recombination limited its wider application. A recently developed fast generation cycling system (FGCS achieved similar times to those of DH for the production of selfed pure lines but is more versatile as it is much less genotype-dependent than DH technology and does not restrict recombination to a single event. The advantages and disadvantages of the technologies and their produced pure line populations for different purposes of biological research and breeding are discussed. The development of a concept of complete in vitro meiosis and mitosis system is also proposed. This could integrate with the recently developed technologies of single cell genomic sequencing and genome wide selection, leading to a complete laboratory based pre-breeding scheme.

  6. Plant genetic resources: what can they contribute toward increased crop productivity?

    Science.gov (United States)

    Hoisington, D; Khairallah, M; Reeves, T; Ribaut, J M; Skovmand, B; Taba, S; Warburton, M

    1999-05-25

    To feed a world population growing by up to 160 people per minute, with >90% of them in developing countries, will require an astonishing increase in food production. Forecasts call for wheat to become the most important cereal in the world, with maize close behind; together, these crops will account for approximately 80% of developing countries' cereal import requirements. Access to a range of genetic diversity is critical to the success of breeding programs. The global effort to assemble, document, and utilize these resources is enormous, and the genetic diversity in the collections is critical to the world's fight against hunger. The introgression of genes that reduced plant height and increased disease and viral resistance in wheat provided the foundation for the "Green Revolution" and demonstrated the tremendous impact that genetic resources can have on production. Wheat hybrids and synthetics may provide the yield increases needed in the future. A wild relative of maize, Tripsacum, represents an untapped genetic resource for abiotic and biotic stress resistance and for apomixis, a trait that could provide developing world farmers access to hybrid technology. Ownership of genetic resources and genes must be resolved to ensure global access to these critical resources. The application of molecular and genetic engineering technologies enhances the use of genetic resources. The effective and complementary use of all of our technological tools and resources will be required for meeting the challenge posed by the world's expanding demand for food.

  7. Local adaptation of plant viruses: lessons from experimental evolution.

    Science.gov (United States)

    Elena, Santiago F

    2017-04-01

    For multihost pathogens, adaptation to multiple hosts has important implications for both applied and basic research. At the applied level, it is one of the main factors determining the probability and severity of emerging disease outbreaks. At the basic level, it is thought to be a key mechanism for the maintenance of genetic diversity both in host and pathogen species. In recent years, a number of evolution experiments have assessed the fate of plant virus populations replicating within and adapting to one single or to multiple hosts species. A first group of these experiments tackled the existence of trade-offs in fitness and virulence for viruses evolving either within a single hosts species or alternating between two different host species. A second set of experiments explored the role of genetic variability in susceptibility and resistance to infection among individuals from the same host species in the extent of virus local adaptation and of virulence. In general, when a single host species or genotype is available, these experiments show that local adaptation takes place, often but not always associated with a fitness trade-off. However, alternating between different host species or infecting resistant host genotypes may select for generalist viruses that experience no fitness cost. Therefore, the expected cost of generalism, arising from antagonistic pleiotropy and other genetic mechanisms generating fitness trade-offs between hosts, could not be generalized and strongly depend on the characteristics of each particular pathosystem. At the genomic level, these studies show pervasive convergent molecular evolution, suggesting that the number of accessible molecular pathways leading to adaptation to novel hosts is limited. © 2016 John Wiley & Sons Ltd.

  8. Plant available nitrogen from anaerobically digested sludge and septic tank sludge applied to crops grown in the tropics.

    Science.gov (United States)

    Sripanomtanakorn, S; Polprasert, C

    2002-04-01

    Agricultural land is an attractive alternative for the disposal of biosolids since it utilises the recyclable nutrients in the production of crops. In Thailand and other tropical regions, limited field-study information exists on the effect of biosolids management strategies on crop N utilisation and plant available N (PAN) of biosolids. A field study was conducted to quantify the PAN of the applied biosolids, and to evaluate the N uptake rates of some tropical crops. Sunflower (Helianthus annuus) and tomato (Lycopersicon esculentum) were chosen in this study. Two types of biosolids used were: anaerobically digested sludge and septic tank sludge. The soil is acid sulfate and is classified as Sulfic Tropaquepts with heavy clay in texture. The anaerobically digested sludge applied rates were: 0, 156 and 312 kg N ha(-1) for the sunflower plots, and 0, 586, and 1172 kg N ha(-1) for the tomato plots. The septic tank sludge applied rates were: 0, 95 and 190 kg N ha(-1) for the sunflower plots, and 0, 354 and 708 kg N ha(-1) for the tomato plots, respectively. The results indicated the feasibility of applying biosolids to grow tropical crops. The applications of the anaerobically digested sludge and the septic tank sludge resulted in the yields of sunflower seeds and tomato fruits and the plant N uptakes comparable or better than that applied with only the chemical fertiliser. The estimated PAN of the anaerobically digested sludge was about 27-42% of the sludge organic N during the growing season. For the septic tank sludge, the PAN was about 15-58% of the sludge organic N. It is interesting to observe that an increase of the rate of septic tank sludge incorporated into this heavy clay soil under the cropping system resulted in the decrease of N mineralisation rate. This situation could cause the reduction of yield and N uptake of crops.

  9. Induced mutation and epigenetics modification in plants for crop improvement by targeting CRISPR/Cas9 technology.

    Science.gov (United States)

    Khan, Muhammad Hafeez Ullah; Khan, Shahid U; Muhammad, Ali; Hu, Limin; Yang, Yang; Fan, Chuchuan

    2018-06-01

    Clustered regularly interspaced palindromic repeats associated protein Cas9 (CRISPR-Cas9), originally an adaptive immunity system of prokaryotes, is revolutionizing genome editing technologies with minimal off-targets in the present era. The CRISPR/Cas9 is now highly emergent, advanced, and highly specific tool for genome engineering. The technology is widely used to animal and plant genomes to achieve desirable results. The present review will encompass how CRISPR-Cas9 is revealing its beneficial role in characterizing plant genetic functions, genomic rearrangement, how it advances the site-specific mutagenesis, and epigenetics modification in plants to improve the yield of field crops with minimal side-effects. The possible pitfalls of using and designing CRISPR-Cas9 for plant genome editing are also discussed for its more appropriate applications in plant biology. Therefore, CRISPR/Cas9 system has multiple benefits that mostly scientists select for genome editing in several biological systems. © 2017 Wiley Periodicals, Inc.

  10. Increasing Crop Yields in Water Stressed Countries by Combining Operations of Freshwater Reservoir and Wastewater Reclamation Plant

    Science.gov (United States)

    Bhushan, R.; Ng, T. L.

    2015-12-01

    Freshwater resources around the world are increasing in scarcity due to population growth, industrialization and climate change. This is a serious concern for water stressed countries, including those in Asia and North Africa where future food production is expected to be negatively affected by this. To address this problem, we investigate the potential of combining freshwater reservoir and wastewater reclamation operations. Reservoir water is the cheaper source of irrigation, but is often limited and climate sensitive. Treated wastewater is a more reliable alternative for irrigation, but often requires extensive further treatment which can be expensive. We propose combining the operations of a reservoir and a wastewater reclamation plant (WWRP) to augment the supply from the reservoir with reclaimed water for increasing crop yields in water stressed regions. The joint system of reservoir and WWRP is modeled as a multi-objective optimization problem with the double objective of maximizing the crop yield and minimizing total cost, subject to constraints on reservoir storage, spill and release, and capacity of the WWRP. We use the crop growth model Aquacrop, supported by The Food and Agriculture Organization of the United Nations (FAO), to model crop growth in response to water use. Aquacrop considers the effects of water deficit on crop growth stages, and from there estimates crop yield. We generate results comparing total crop yield under irrigation with water from just the reservoir (which is limited and often interrupted), and yield with water from the joint system (which has the potential of higher supply and greater reliability). We will present results for locations in India and Africa to evaluate the potential of the joint operations for improving food security in those areas for different budgets.

  11. The Colletotrichum acutatum Species Complex as a Model System to Study Evolution and Host Specialization in Plant Pathogens

    Science.gov (United States)

    Baroncelli, Riccardo; Talhinhas, Pedro; Pensec, Flora; Sukno, Serenella A.; Le Floch, Gaetan; Thon, Michael R.

    2017-01-01

    Colletotrichum spp. infect a wide diversity of hosts, causing plant diseases on many economically important crops worldwide. The genus contains approximately 189 species organized into at least 11 major phylogenetic lineages, also known as species complexes. The Colletotrichum acutatum species complex is a diverse yet relatively closely related group of plant pathogenic fungi within this genus. Within the species complex we find a wide diversity of important traits such as host range and host preference, mode of reproduction and differences in the strategy used to infect their hosts. Research on fungal comparative genomics have attempted to find correlations in these traits and patterns of gene family evolution but such studies typically compare fungi from different genera or even different fungal Orders. The C. acutatum species complex contains most of this diversity within a group of relatively closely related species. This Perspective article presents a review of the current knowledge on C. acutatum phylogeny, biology, and pathology. It also demonstrates the suitability of C. acutatum for the study of gene family evolution on a fine scale to uncover evolutionary events in the genome that are associated with the evolution of phenotypic characters important for host interactions. PMID:29075253

  12. The Colletotrichum acutatum Species Complex as a Model System to Study Evolution and Host Specialization in Plant Pathogens

    Directory of Open Access Journals (Sweden)

    Riccardo Baroncelli

    2017-10-01

    Full Text Available Colletotrichum spp. infect a wide diversity of hosts, causing plant diseases on many economically important crops worldwide. The genus contains approximately 189 species organized into at least 11 major phylogenetic lineages, also known as species complexes. The Colletotrichum acutatum species complex is a diverse yet relatively closely related group of plant pathogenic fungi within this genus. Within the species complex we find a wide diversity of important traits such as host range and host preference, mode of reproduction and differences in the strategy used to infect their hosts. Research on fungal comparative genomics have attempted to find correlations in these traits and patterns of gene family evolution but such studies typically compare fungi from different genera or even different fungal Orders. The C. acutatum species complex contains most of this diversity within a group of relatively closely related species. This Perspective article presents a review of the current knowledge on C. acutatum phylogeny, biology, and pathology. It also demonstrates the suitability of C. acutatum for the study of gene family evolution on a fine scale to uncover evolutionary events in the genome that are associated with the evolution of phenotypic characters important for host interactions.

  13. Uptake of perfluoroalkyl substances and halogenated flame retardants by crop plants grown in biosolids-amended soils.

    Science.gov (United States)

    Navarro, Irene; de la Torre, Adrián; Sanz, Paloma; Porcel, Miguel Ángel; Pro, Javier; Carbonell, Gregoria; Martínez, María de Los Ángeles

    2017-01-01

    The bioaccumulation behavior of perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) was examined in three horticultural crops and earthworms. Two species, spinach (Spinacia oleracea) and tomato (Solanum lycopersicum L.), were grown in field soil amended with a single application of biosolids (at agronomic rate for nitrogen), to represent the scenario using commercial biosolids as fertilizer, and the third crop, corn (Zea mays) was grown in spiked soil (~50mg PFOS/kg soil, ~5mg Deca-BDE/kg soil and a mixture of both, ~50mg PFOS and ~5mg Deca-BDE/kg soil) to represent a worst-case scenario. To examine the bioaccumulation in soil invertebrates, earthworms (Eisenia andrei) were exposed to the spiked soil where corn had been grown. PFASs and HFRs were detected in the three crops and earthworms. To evaluate the distribution of the compounds in the different plant tissues, transfer factors (TFs) were calculated, with TF values higher for PFASs than PBDEs in all crop plants: from 2 to 9-fold in spinach, 2 to 34-fold in tomato and 11 to 309-fold in corn. Bioaccumulation factor (BAF) values in earthworms were also higher for PFASs (4.06±2.23) than PBDEs (0.02±0.02). Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Evolutionary Origin, Gradual Accumulation and Functional Divergence of Heat Shock Factor Gene Family with Plant Evolution

    Directory of Open Access Journals (Sweden)

    Xiaoming Wang

    2018-02-01

    Full Text Available Plants, as sessile organisms, evolved a complex and functionally diverse heat shock factor (HSF gene family to cope with various environmental stresses. However, the limited evolution studies of the HSF gene family have hindered our understanding of environmental adaptations in plants. In this study, a comprehensive evolution analysis on the HSF gene family was performed in 51 representative plant species. Our results demonstrated that the HSFB group which lacks a typical AHA activation domain, was the most ancient, and is under stronger purifying selection pressure in the subsequent evolutionary processes. While, dramatic gene expansion and functional divergence occurred at evolution timescales corresponding to plant land inhabit, which contribute to the emergence and diversification of the HSFA and HSFC groups in land plants. During the plant evolution, the ancestral functions of HSFs were maintained by strong purifying pressure that acted on the DNA binding domain, while the variable oligomerization domain and motif organization of HSFs underwent functional divergence and generated novel subfamilies. At the same time, variations were further accumulated with plant evolution, and this resulted in remarkable functional diversification among higher plant lineages, including distinct HSF numbers and selection pressures of several HSF subfamilies between monocots and eudicots, highlighting the fundamental differences in different plant lineages in response to environmental stresses. Taken together, our study provides novel insights into the evolutionary origin, pattern and selection pressure of plant HSFs and delineates critical clues that aid our understanding of the adaptation processes of plants to terrestrial environments.

  15. Environmental stress-mediated changes in transcriptional and translational regulation of protein synthesis in crop plants. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Key, J.L.

    1983-01-01

    Work during the 2 1/2 years of this contract has focused on: (1) descriptive biology of the heat shock (hs) response of soybean seedlings, (2) cDNA cloning and characterization of several hs specific mRNA sequences, (3) comparative analysis of the hs response in several crop plant systems using in vivo labeling/2D gel analysis of the newly synthesized proteins and soybean hs cDNA clones in northern hybridization analysis of hs mRNAs, (4) comparative analysis between different environmental stresses and hs in soybean using cloned cDNA, (5) an analysis of the physiological significance of the hs response in crop plants - thermal tolerance and selective localization of the hs proteins (hsp's) and (6) the influence of hs on normal (28/sup 0/) RNA metabolism.

  16. Cultivar and planting date selection for relay-cropping soybean with winter oilseeds

    Science.gov (United States)

    Double- and relay-cropping soybean with winter camelina (Camelina sativa L. Crantz) and pennycress (Thlaspi arvense L.) have been shown to be viable cropping systems for the Upper Midwest. Relaying soybean with these winter oilseeds can result in greater total seed yield (i.e., both combined) and ec...

  17. A rapid and efficient method to study the function of crop plant transporters in Arabidopsis

    Science.gov (United States)

    Iron (Fe) is an essential micronutrient for humans. Fe deficiency disease is wide-spread and has lead to extensive studies on the mechanisms of Fe uptake and storage, especially in staple food crops such as rice. However, studies of functionally related genes in rice and other crops are often time a...

  18. Simulating the partitioning of biomass and nitrogen between roots and shoot in crop and grass plants

    NARCIS (Netherlands)

    Yin, X.; Schapendonk, A.H.C.M.

    2004-01-01

    Quantification of the assimilate partitioning between roots and shoot has been one of the components that need improvement in crop growth models. In this study we derived two equations for root-shoot partitioning of biomass and nitrogen (N) that hold for crops grown under steady-state conditions.

  19. Biofertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity

    OpenAIRE

    Bhardwaj, Deepak; Ansari, Mohammad Wahid; Sahoo, Ranjan Kumar; Tuteja, Narendra

    2014-01-01

    Current soil management strategies are mainly dependent on inorganic chemical-based fertilizers, which caused a serious threat to human health and environment. The exploitation of beneficial microbes as a biofertilizer has become paramount importance in agriculture sector for their potential role in food safety and sustainable crop production. The eco-friendly approaches inspire a wide range of application of plant growth promoting rhizobacteria (PGPRs), endo- and ectomycorrhizal fungi, cyano...

  20. Root isolations of Metarhizium spp. from crops reflect diversity in the soil and indicate no plant specificity.

    Science.gov (United States)

    Steinwender, Bernhardt M; Enkerli, Jürg; Widmer, Franco; Eilenberg, Jørgen; Kristensen, Hanne L; Bidochka, Michael J; Meyling, Nicolai V

    2015-11-01

    Metarhizium spp. have recently been shown to be associated with the roots of different plants. Here we evaluated which Metarhizium species were associated with roots of oat (Avena sativa), rye (Secale cereale) and cabbage (Brassica oleracea), common crop plants in Denmark. Thirty-six root samples from each of the three crops were collected within an area of approximately 3ha. The roots were rinsed with sterile water, homogenized and the homogenate plated onto selective media. A subset of 126 Metarhizium isolates were identified to species by sequencing of the 5' end of the gene translation elongation factor 1-alpha and characterized by simple sequence repeat (SSR) analysis of 14 different loci. Metarhizium brunneum was the most common species isolated from plant roots (84.1% of all isolates), while M. robertsii (11.1%) and M. majus (4.8%) comprised the remainder. The SSR analysis revealed that six multilocus genotypes (MLGs) were present among the M. brunneum and M. robertsii isolates, respectively. A single MLG of M. brunneum represented 66.7%, 79.1% and 79.2% of the total isolates obtained from oat, rye and cabbage, respectively. The isolation of Metarhizium spp. and their MLGs from roots revealed a comparable community composition as previously reported from the same agroecosystem when insect baiting of soil samples was used as isolating technique. No specific MLG association with a certain crop was found. This study highlights the diversity of Metarhizium spp. found in the rhizosphere of different crops within a single agroecosystem and suggests that plants either recruit fungal associates from the surrounding soil environment or even govern the composition of Metarhizium populations. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Effects of Planting Dates, Irrigation Management and Cover Crops on Growth and Yield of Saffron (Crocus sativus L.

    Directory of Open Access Journals (Sweden)

    A Koocheki

    2017-01-01

    Full Text Available Introduction Saffron as a winter active plant with low water requirement is the most strategic medicinal plant in arid and semi-arid parts of Iran. This slow-growing plant has narrow leaves and no aerial stem, hence weeds can be overcome it. Moreover, because of its root and canopy structure an important part of different resources is not used by this low input crop. Therefore, the use of associated crops could be an effective way for increasing resources use efficiencies (Koocheki et al., 2016. Appropriate corm planting date is another important factor that affects saffron growth and yield. Results of some studies show that late spring is the best time for corm planting (Ghasemi-Rooshnavand, 2009; Koocheki et al., 2016. In addition, irrigation management has been evaluated in some studies, but irrigation immediately after corm planting has not been investigated previously. Therefore, the aim of this study was to investigate the effect of irrigation management, planting date and the use of some companion crops on flowering of saffron during two growth cycles. Materials and methods This experiment was carried out as a split-split plot experiment based on a Randomized Complete Block Design with three replications at Research Station, Ferdowsi University of Mashhad, Iran in 2009-2011. Experimental factors included: planting date of saffron as main factor (first of June, first of August and first of October, 2009, the irrigation management as sub factor (irrigation and no irrigation after each planting date and the companion crops as sub-sub factor [Persian clover (Trifolium resupinatum, Bitter vetch (Lathyrus sativus and control. Corm planting was done in 10×25 cm distances with 12 cm depth. In the second year irrigation was done again in the plots which were irrigated after planting in the first year at the same previous dates. Companion crops were sown after first flower picking (November, 2009, then their residue were returned to the soil in

  2. Crop quality control system: a tool to control the visual quality of pot plants

    NARCIS (Netherlands)

    Dijkshoorn-Dekker, M.W.C.

    2002-01-01

    Key words: quality, growth, model, leaf unfolding rate, internode, plant height, plant width, leaf area, temperature, plant spacing, season, light, development, image processing, grading, neural network, pot plant, Ficus benjamina

  3. Effect of planting date and crop density of autumn wheat (Triticum aestivum L. on density and biomass of weeds

    Directory of Open Access Journals (Sweden)

    R. Ghorbani

    2016-05-01

    Full Text Available Weeds in wheat (Triticum aestivum L. fields have always been a big problem in Iran and worldwide and must be managed by non-chemical especially cultural methods. A field experiment as factorial based on a randomized complete block design with four replications in a 1000 m2 field in Research Farm of Shirvan College of Agriculture was conducted during 2007-2008. Treatments included wheat densities of 400, 600 and 800 plants.m-2and planting dates of 1st of Nov., 20th of Nov., and 1st of Dec 2007. The results represented that the presence of Rapistrum rogusum, Phalaris spp., Descurainia sophia, Alopecurus myosurides and Hordeum murinum dominance. Delay in planting of wheat increased relative density of weeds. The lowest relative frequency of weeds was observed in planting date of 1st of November. Increase in crop density significantly decreased weed biomass, while it showed little effect on weed density trend. Effect of planting date was also significant on weed biomass. The highest weed biomass occurred in the planting date of Dec. the 1st. In conclusion, delay in planting of wheat create more chance and space for weed establishment, and therefore planting dense (600 plants.m-2 and early in season of wheat is recommended for lower weed damage.

  4. The recent recombinant evolution of a major crop pathogen, potato virus Y.

    Directory of Open Access Journals (Sweden)

    Johan Christiaan Visser

    Full Text Available Potato virus Y (PVY is a major agricultural disease that reduces crop yields worldwide. Different strains of PVY are associated with differing degrees of pathogenicity, of which the most common and economically important are known to be recombinant. We need to know the evolutionary origins of pathogens to prevent further escalations of diseases, but putatively reticulate genealogies are challenging to reconstruct with standard phylogenetic approaches. Currently available phylogenetic hypotheses for PVY are either limited to non-recombinant strains, represent only parts of the genome, and/or incorrectly assume a strictly bifurcating phylogenetic tree. Despite attempts to date potyviruses in general, no attempt has been made to date the origins of pathogenic PVY. We test whether diversification of the major strains of PVY and recombination between them occurred within the time frame of the domestication and modern cultivation of potatoes. In so doing, we demonstrate a novel extension of a phylogenetic approach for reconstructing reticulate evolutionary scenarios. We infer a well resolved phylogeny of 44 whole genome sequences of PVY viruses, representative of all known strains, using recombination detection and phylogenetic inference techniques. Using Bayesian molecular dating we show that the parental strains of PVY diverged around the time potatoes were first introduced to Europe, that recombination between them only occurred in the last century, and that the multiple recombination events that led to highly pathogenic PVY(NTN occurred within the last 50 years. Disease causing agents are often transported across the globe by humans, with disastrous effects for us, our livestock and crops. Our analytical approach is particularly pertinent for the often small recombinant genomes involved (e.g. HIV/influenza A. In the case of PVY, increased transport of diseased material is likely to blame for uniting the parents of recombinant pathogenic strains

  5. RNA Interference (RNAi) as a Potential Tool for Control of Mycotoxin Contamination in Crop Plants: Concepts and Considerations.

    Science.gov (United States)

    Majumdar, Rajtilak; Rajasekaran, Kanniah; Cary, Jeffrey W

    2017-01-01

    Mycotoxin contamination in food and feed crops is a major concern worldwide. Fungal pathogens of the genera Aspergillus. Fusarium , and Penicillium are a major threat to food and feed crops due to production of mycotoxins such as aflatoxins, 4-deoxynivalenol, patulin, and numerous other toxic secondary metabolites that substantially reduce the value of the crop. While host resistance genes are frequently used to introgress disease resistance into elite germplasm, either through traditional breeding or transgenic approaches, such resistance is often compromised by the evolving pathogen over time. RNAi-based host-induced gene silencing of key genes required by the pathogen for optimal growth, virulence and/or toxin production, can serve as an alternative, pre-harvest approach for disease control. RNAi represents a robust and efficient tool that can be used in a highly targeted, tissue specific manner to combat mycotoxigenic fungi infecting crop plants. Successful transgenic RNAi implementation depends on several factors including (1) designing vectors to produce double-stranded RNAs (dsRNAs) that will generate small interfering RNA (siRNA) species for optimal gene silencing and reduced potential for off-target effects; (2) availability of ample target siRNAs at the infection site; (3) efficient uptake of siRNAs by the fungus; (4) siRNA half-life and (5) amplification of the silencing effect. This review provides a critical and comprehensive evaluation of the published literature on the use of RNAi-based approaches to control mycotoxin contamination in crop plants. It also examines experimental strategies used to better understand the mode of action of RNAi with the aim of eliminating mycotoxin contamination, thereby improving food and feed safety.

  6. Growth and development of plants with potential for use as trap crops for potato cyst nematodes and their effects on the numbers of juveniles in cysts

    NARCIS (Netherlands)

    Scholte, K.

    2000-01-01

    Growth and development of three plant accessions with potential for use as trap crops for potato cyst nematodes (PCN), Solanum sisymbriifolium and two varieties of S. nigrum, were studied under 12 h and 17 h photoperiods. In pot experiments, rate of plant emergence, plant height, and shoot and root

  7. Hormonal and metabolic regulation of source-sink relations under salinity and drought: from plant survival to crop yield stability.

    Science.gov (United States)

    Albacete, Alfonso A; Martínez-Andújar, Cristina; Pérez-Alfocea, Francisco

    2014-01-01

    Securing food production for the growing population will require closing the gap between potential crop productivity under optimal conditions and the yield captured by farmers under a changing environment, which is termed agronomical stability. Drought and salinity are major environmental factors contributing to the yield gap ultimately by inducing premature senescence in the photosynthetic source tissues of the plant and by reducing the number and growth of the harvestable sink organs by affecting the transport and use of assimilates between and within them. However, the changes in source-sink relations induced by stress also include adaptive changes in the reallocation of photoassimilates that influence crop productivity, ranging from plant survival to yield stability. While the massive utilization of -omic technologies in model plants is discovering hundreds of genes with potential impacts in alleviating short-term applied drought and salinity stress (usually measured as plant survival), only in relatively few cases has an effect on crop yield stability been proven. However, achieving the former does not necessarily imply the latter. Plant survival only requires water status conservation and delayed leaf senescence (thus maintaining source activity) that is usually accompanied by growth inhibition. However, yield stability will additionally require the maintenance or increase in sink activity in the reproductive structures, thus contributing to the transport of assimilates from the source leaves and to delayed stress-induced leaf senescence. This review emphasizes the role of several metabolic and hormonal factors influencing not only the source strength, but especially the sink activity and their inter-relations, and their potential to improve yield stability under drought and salinity stresses. © 2013.

  8. How endogenous plant pararetroviruses shed light on Musa evolution

    Science.gov (United States)

    Duroy, Pierre-Olivier; Perrier, Xavier; Laboureau, Nathalie; Jacquemoud-Collet, Jean-Pierre; Iskra-Caruana, Marie-Line

    2016-01-01

    Background and Aims Banana genomes harbour numerous copies of viral sequences derived from banana streak viruses (BSVs) – dsDNA viruses belonging to the family Caulimoviridae. These viral integrants (eBSVs) are mostly defective, probably as a result of ‘pseudogenization’ driven by host genome evolution. However, some can give rise to infection by releasing a functional viral genome following abiotic stresses. These distinct infective eBSVs correspond to the three main widespread BSV species (BSOLV, BSGFV and BSIMV), fully described within the Musa balbisiana B genomes of the seedy diploid ‘Pisang Klutuk Wulung’ (PKW). Methods We characterize eBSV distribution among a Musa sampling including seedy BB diploids and interspecific hybrids with Musa acuminata exhibiting different levels of ploidy for the B genome (ABB, AAB, AB). We used representative samples of the two areas of sympatry between M. acuminata and M. balbisiana species representing the native area of the most widely cultivated AAB cultivars (in India and in East Asia, ranging from the Philippines to New Guinea). Seventy-seven accessions were characterized using eBSV-related PCR markers and Southern hybridization approaches. We coded both sets of results to create a common dissimilarity matrix with which to interpret eBSV distribution. Key Results We propose a Musa phylogeny driven by the M. balbisiana genome based on a dendrogram resulting from a joint neighbour-joining analysis of the three BSV species, showing for the first time lineages between BB and ABB/AAB hybrids. eBSVs appear to be relevant phylogenetic markers that can illustrate the M. balbisiana phylogeography story. Conclusion The theoretical implications of this study for further elucidation of the historical and geographical process of Musa domestication are numerous. Discovery of banana plants with B genome non-infective for eBSV opens the way to the introduction of new genitors in programmes of genetic banana improvement. PMID

  9. Planting Date and Seeding Rate Effects on Sunn Hemp Biomass and Nitrogen Production for a Winter Cover Crop

    Directory of Open Access Journals (Sweden)

    Kipling S. Balkcom

    2011-01-01

    Full Text Available Sunn hemp (Crotalaria juncea L. is a tropical legume that produces plant biomass and nitrogen (N quickly. Our objectives were to assess the growth of a new sunn hemp cultivar breed to produce seed in a temperate climate and determine the residual N effect on a rye (Secale cereale L. cover crop in east-central Alabama from 2007 to 2009. Plant populations, plant height, stem diameter, biomass production, and N content were determined for two sunn hemp planting dates, following corn (Zea mays L. and wheat (Triticum aestivum L. harvest, across different seeding rates (17, 34, 50, and 67 kg/ha. Rye biomass was measured the following spring. Sunn hemp biomass production was inconsistent across planting dates, but did relate to growing degree accumulation. Nitrogen concentrations were inversely related to biomass production, and subsequent N contents corresponded to biomass levels. Neither planting date nor seeding rate affected rye biomass production, but rye biomass averaged over both planting dates following wheat/sunn hemp averaged 43% and 33% greater than rye following fallow. Rye biomass following corn/sunn hemp was equivalent to fallow plots. Early planting dates are recommended for sunn hemp with seeding rates between 17 and 34 kg/ha to maximize biomass and N production.

  10. Intensity of Ground Cover Crop Arachis pintoi, Rhizobium Inoculation and Phosphorus Application and Their Effects on Field Growth and Nutrient Status of Cocoa Plants

    Directory of Open Access Journals (Sweden)

    John Bako Baon

    2006-08-01

    Full Text Available Arachis pintoiis potentially as a cover crop for cocoa (Theobroma cacaoL. farm, however information regarding its effect on the growth of cocoa plants in the field is very limited. The objective of this experiment is to investigate the combined influence of ground cover crop A. pintoi, rhizobial bacterial inoculation and phosphorus (P fertilizer on the growth of cocoa in the field and nutrient status. This experiment laid out in split-split plot design consisted of three levels of cover crop (without, A. pintoiand Calopogonium caeruleum, two levels of rhizobium inoculation (not inoculated and inoculated and two levels of phosphorus application (no P added and P added. The results showed that in field condition the presence of A. pintoias cover crop did not affect the growth of cocoa. On the other hand, C. caeruleumas cover crop tended to restrict cocoa growth compared to A. pintoi. Application of P increased leaf number of cocoa plant. Biomass production of A. pintoiwas 40% higher than C. caeruleum. Soil organic carbon and nitrogen contents were not affected by ground cover crops, though higher value (0.235% N and 1.63% organic C was obtained from combined treatments of inoculation and P addition or neither inoculation nor P addition. In the case of no rhizobium inoculation, soil N content in cocoa farm with A. pintoicover crop was lower than that of without cover crop or with C. caeruleum. Cover crop increased plant N content when there was no inoculation, on the other hand rhizobium inoculation decreased N content of cocoa tissue. Tissue P content of cocoa plant was not influenced by A. Pintoicover crop or by rhizobium inoculation, except that the P tissue content of cocoa was 28% higher when the cover crop was C. caeruleumand inoculated. Key words : Arachis pintoi, Theobroma cacao, Calopogonium caeruleum, rhizobium, nitrogen, phosphorus.

  11. A photorespiratory bypass increases plant growth and seed yield in biofuel crop Camelinasativa

    National Research Council Canada - National Science Library

    Dalal, Jyoti; Lopez, Harry; Vasani, Naresh B; Hu, Zhaohui; Swift, Jennifer E; Yalamanchili, Roopa; Dvora, Mia; Lin, Xiuli; Xie, Deyu; Qu, Rongda; Sederoff, Heike W

    2015-01-01

    is an oilseed crop with great potential for biofuel production on marginal land. The seed oil from camelina has been converted to jet fuel and improved fuel efficiency in commercial and military test flights...

  12. The Technology Roadmap for Plant/Crop-Based Renewable Resources 2020

    National Research Council Canada - National Science Library

    2005-01-01

    .... Renewable materials from home-grown crops trees and agricultural wastes can provide many of the same chemical building blocks-plus others that petrochemicals cannot Despite the expertise and ingenuity of U.S...

  13. Facilitated by nature and agriculture: performance of a specialist herbivore improves with host-plant life history evolution, domestication, and breeding.

    Science.gov (United States)

    Dávila-Flores, Amanda M; DeWitt, Thomas J; Bernal, Julio S

    2013-12-01

    Plant defenses against herbivores are predicted to change as plant lineages diversify, and with domestication and subsequent selection and breeding in the case of crop plants. We addressed whether defense against a specialist herbivore declined coincidently with life history evolution, domestication, and breeding within the grass genus Zea (Poaceae). For this, we assessed performance of corn leafhopper (Dalbulus maidis) following colonization of one of four Zea species containing three successive transitions: the evolutionary transition from perennial to annual life cycle, the agricultural transition from wild annual grass to primitive crop cultivar, and the agronomic transition from primitive to modern crop cultivar. Performance of corn leafhopper was measured through seven variables relevant to development speed, survivorship, fecundity, and body size. The plants included in our study were perennial teosinte (Zea diploperennis), Balsas teosinte (Zea mays parviglumis), a landrace maize (Zea mays mays), and a hybrid maize. Perennial teosinte is a perennial, iteroparous species, and is basal in Zea; Balsas teosinte is an annual species, and the progenitor of maize; the landrace maize is a primitive, genetically diverse cultivar, and is ancestral to the hybrid maize; and, the hybrid maize is a highly inbred, modern cultivar. Performance of corn leafhopper was poorest on perennial teosinte, intermediate on Balsas teosinte and landrace maize, and best on hybrid maize, consistent with our expectation of declining defense from perennial teosinte to hybrid maize. Overall, our results indicated that corn leafhopper performance increased most with the agronomic transition, followed by the life history transition, and least with the domestication transition.

  14. Crop growth, light utilization and yield of relay intercropped cotton as affected by plant density and a plant growth regulator

    NARCIS (Netherlands)

    Mao, L.; Zhang, L.; Zhao, X.; Liu, S.; Werf, van der W.; Zhang, S.; Spiertz, J.H.J.; Li, Z.

    2014-01-01

    Modern cotton cultivation requires high plant densities and compact plants. Here we study planting density and growth regulator effects on plant structure and production of cotton when the cotton is grown in a relay intercrop with wheat, a cultivation system that is widespread in China. Field

  15. Plant Stress Responses and Phenotypic Plasticity in the Epigenomics Era: Perspectives on the Grapevine Scenario, a Model for Perennial Crop Plants.

    Science.gov (United States)

    Fortes, Ana M; Gallusci, Philippe

    2017-01-01

    Epigenetic marks include Histone Post-Translational Modifications and DNA methylation which are known to participate in the programming of gene expression in plants and animals. These epigenetic marks may be subjected to dynamic changes in response to endogenous and/or external stimuli and can have an impact on phenotypic plasticity. Studying how plant genomes can be epigenetically shaped under stressed conditions has become an essential issue in order to better understand the molecular mechanisms underlying plant stress responses and enabling epigenetic in addition to genetic factors to be considered when breeding crop plants. In this perspective, we discuss the contribution of epigenetic mechanisms to our understanding of plant responses to biotic and abiotic stresses. This regulation of gene expression in response to environment raises important biological questions for perennial species such as grapevine which is asexually propagated and grown worldwide in contrasting terroirs and environmental conditions. However, most species used for epigenomic studies are annual herbaceous plants, and epigenome dynamics has been poorly investigated in perennial woody plants, including grapevine. In this context, we propose grape as an essential model for epigenetic and epigenomic studies in perennial woody plants of agricultural importance.

  16. How healthy is urban horticulture in high traffic areas? Trace metal concentrations in vegetable crops from plantings within inner city neighbourhoods in Berlin, Germany.

    Science.gov (United States)

    Säumel, Ina; Kotsyuk, Iryna; Hölscher, Marie; Lenkereit, Claudia; Weber, Frauke; Kowarik, Ingo

    2012-06-01

    Food production by urban dwellers is of growing importance in developing and developed countries. Urban horticulture is associated with health risks as crops in urban settings are generally exposed to higher levels of pollutants than those in rural areas. We determined the concentration of trace metals in the biomass of different horticultural crops grown in the inner city of Berlin, Germany, and analysed how the local setting shaped the concentration patterns. We revealed significant differences in trace metal concentrations depending on local traffic, crop species, planting style and building structures, but not on vegetable type. Higher overall traffic burden increased trace metal content in the biomass. The presence of buildings and large masses of vegetation as barriers between crops and roads reduced trace metal content in the biomass. Based on this we discuss consequences for urban horticulture, risk assessment, and planting and monitoring guidelines for cultivation and consumption of crops. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Changing techniques in crop plant classification: molecularization at the National Institute of Agricultural Botany during the 1980s.

    Science.gov (United States)

    Holmes, Matthew

    2017-04-01

    Modern methods of analysing biological materials, including protein and DNA sequencing, are increasingly the objects of historical study. Yet twentieth-century taxonomic techniques have been overlooked in one of their most important contexts: agricultural botany. This paper addresses this omission by harnessing unexamined archival material from the National Institute of Agricultural Botany (NIAB), a British plant science organization. During the 1980s the NIAB carried out three overlapping research programmes in crop identification and analysis: electrophoresis, near infrared spectroscopy (NIRS) and machine vision systems. For each of these three programmes, contemporary economic, statutory and scientific factors behind their uptake by the NIAB are discussed. This approach reveals significant links between taxonomic practice at the NIAB and historical questions around agricultural research, intellectual property and scientific values. Such links are of further importance given that the techniques developed by researchers at the NIAB during the 1980s remain part of crop classification guidelines issued by international bodies today.

  18. A new synthetic biology approach allows transfer of an entire metabolic pathway from a medicinal plant to a biomass crop.

    Science.gov (United States)

    Fuentes, Paulina; Zhou, Fei; Erban, Alexander; Karcher, Daniel; Kopka, Joachim; Bock, Ralph

    2016-06-14

    Artemisinin-based therapies are the only effective treatment for malaria, the most devastating disease in human history. To meet the growing demand for artemisinin and make it accessible to the poorest, an inexpensive and rapidly scalable production platform is urgently needed. Here we have developed a new synthetic biology approach, combinatorial supertransformation of transplastomic recipient lines (COSTREL), and applied it to introduce the complete pathway for artemisinic acid, the precursor of artemisinin, into the high-biomass crop tobacco. We first introduced the core pathway of artemisinic acid biosynthesis into the chloroplast genome. The transplastomic plants were then combinatorially supertransformed with cassettes for all additional enzymes known to affect flux through the artemisinin pathway. By screening large populations of COSTREL lines, we isolated plants that produce more than 120 milligram artemisinic acid per kilogram biomass. Our work provides an efficient strategy for engineering complex biochemical pathways into plants and optimizing the metabolic output.

  19. Co-Evolution of Insect Proteases and Plant Protease Inhibitors.

    NARCIS (Netherlands)

    Jongsma, M.A.; Beekwilder, M.J.

    2011-01-01

    Plants are at the basis of the food chain, but there is no such thing as a “free lunch” for herbivores. To promote reproductive success, plants evolved multi-layered defensive tactics to avoid or discourage herbivory. To the detriment of plants, herbivores, in turn, evolved intricate strategies to

  20. Cocowood fibrovascular tissue system – another wonder of plant evolution

    Directory of Open Access Journals (Sweden)

    Oswaldo Mauricio González

    2016-08-01

    Full Text Available The coconut palm (Cocos nucifera L. stem tissue (referred to as cocowood in this study is a complex fibrovascular system that is made up of fibrovascular bundles embedded into a parenchymatous ground tissue. The complex configuration of fibrovascular bundles along with the non-uniform distribution of the material properties likely allow senile coconut stems to optimize their biomechanical performance per unit mass (i.e. mechanical efficiency and grow into tall, slender and very flexible plants with minimum resources of biomass and water. For the first time, to the best of the authors’ knowledge, this paper examines, from the integral (i.e. stem structure and macroscopic (i.e. tissue structure levels of hierarchy, the characteristic triple helix formation depicted by the fibrovascular bundles within the monocotyledon cocowood. The natural course of the tangential orientation of the axial fibrovascular bundles is mapped for the whole cocowood structure by quantifying 264 cocowood discs, corresponding to 41 senile coconut palms estimated to be greater than 70 years old. The observed variations were modelled in this paper by simple equations that partially enabled characterization of the cocowood fibrovascular tissue system. Furthermore, 11 finite element analyses (FEA were performed over a three dimensional (3D finite element (FE model resembling a characteristic coconut palm stem of 25 m in height to analyze the biomaterial reactions produced by the progressive deviation of the tangential fibrovascular bundles on the cocowood mechanical response (i.e. on the material compressive strength and the bending stiffness. The analyses in this study were carried out for the critical wind speed of 23 m/s (i.e. Gale tornado according to the Fujita tornado scale. For each analysis, the characteristic average maxima degree of orientation of the cocowood fibrovascular bundles was varied from 0˚ to 51˚. The acquired results provided a deep understanding of

  1. Uptake and accumulation of selenium by terrestrial plants growing on a coal fly ash landfill. 2. Forage and root crops

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, M.A.; Rubin, G.; Woodbury, P.B.; Schneider, R.E.; Weinstein, L.H. (Boyce Thompson Institute for Plant Research, Ithaca, NY (USA). Environmental Biology Program)

    1992-09-01

    Plants grown on fly ash landfills can accumulate relatively high concentrations of selenium (Se), although concentrations can vary greatly among and within species. The accumulation of Se in forage and root crops grown on a fly ash landfill and nonlandfill sites and the relationship of soil Se to plant Se concentrations were examined. Because sulfur (S) can act as a competitive ion with Se in plant uptake of nutrients, gypsum (CaSO[sub 4].2H[sub 2]O) was applied to soil on a fly ash landfill to determine whether Se was reduced in plants in its presence. Slightly more Se was accumulated in plants grown on the landfill than on the nonlandfill site. Total Se concentration in soil was poorly correlated with Se concentration in alfalfa plants grown on the landfill. In alfalfa ([ital Medicago sativa L.]), oats ([ital Avena sativa L.]), and rutabaga ([ital Brassica napus L.]), application of gypsum at rates of 5.6 to 16.8 t ha[sup -1] reduced the uptake of Se from that of plants grown without gypsum. Results from this study indicate that gypsum amendment may be effective in decreasing the uptake of Se by plants growing on a fly ash landfill, but the response is quite variable, probably due to variability in concentration and availability of Se in the soil cap. The use of gypsum in limiting Se uptake by plants offers a possible management tool to control the cycling of Se through plants to other biota on fly ash landfills.

  2. Evolution of plant parasitism in the phylum Nematoda.

    Science.gov (United States)

    Quist, Casper W; Smant, Geert; Helder, Johannes

    2015-01-01

    Within the species-rich and trophically diverse phylum Nematoda, at least four independent major lineages of plant parasites have evolved, and in at least one of these major lineages plant parasitism arose independently multiple times. Ribosomal DNA data, sequence information from nematode-produced, plant cell wall-modifying enzymes, and the morphology and origin of the style(t), a protrusible piercing device used to penetrate the plant cell wall, all suggest that facultative and obligate plant parasites originate from fungivorous ancestors. Data on the nature and diversification of plant cell wall-modifying enzymes point at multiple horizontal gene transfer events from soil bacteria to bacterivorous nematodes resulting in several distinct lineages of fungal or oomycete-feeding nematodes. Ribosomal DNA frameworks with sequence data from more than 2,700 nematode taxa combined with detailed morphological information allow for explicit hypotheses on the origin of agronomically important plant parasites, such as root-knot, cyst, and lesion nematodes.

  3. Evolution and applications of plant pathway resources and databases

    DEFF Research Database (Denmark)

    Sucaet, Yves; Deva, Taru

    2011-01-01

    systems deserves much more attention. Study of plant biological pathways, the interconnection between these pathways and plant systems biology on the whole has in general lagged behind human systems biology. In this article we review plant pathway databases and the resources that are currently available....... We lay out trends and challenges in the ongoing efforts to integrate plant pathway databases and the applications of database integration. We also discuss how progress in non-plant communities can serve as an example for the improvement of the plant pathway database landscape and thereby allow...... quantitative modeling of plant biosystems. We propose Good Database Practice as a possible model for collaboration and to ease future integration efforts....

  4. Estimating potential productivity cobenefits for crops and trees from reduced ozone with U.S. coal power plant carbon standards

    Science.gov (United States)

    Capps, Shannon L.; Driscoll, Charles T.; Fakhraei, Habibollah; Templer, Pamela H.; Craig, Kenneth J.; Milford, Jana B.; Lambert, Kathleen F.

    2016-12-01

    A standard for carbon dioxide emissions from power plants in the United States, known as the Clean Power Plan, has been finalized by the Environmental Protection Agency. Decreases in carbon dioxide emissions from fossil fuel combustion have the potential cobenefit of reductions in emissions of oxides of nitrogen, which contribute to the formation of ground-level ozone. Emissions of ozone precursors may result in elevated ozone concentrations nearby or downwind. Chronic exposure of sensitive vegetation to tropospheric ozone reduces its potential productivity. To evaluate the cobenefits of the Clean Power Plan to sensitive vegetation, we estimate ozone concentrations in the continental U.S. in 2020 with a chemical transport model in accordance with reference and alternative Clean Power Plan policy scenarios, which represent a range of possible approaches to reducing carbon dioxide emissions from power plants. The reductions in biomass, or the potential productivity losses, due to the exposure of 4 crops and 11 tree species to ozone are as large as 1.9% and 32%, respectively, in the reference scenario. The least stringent policy scenario reduces these losses by less than 3% for any given species; however, the scenarios consistent with policies resulting in more rigorous nitrogen oxide reductions produce potential productivity losses lower than the reference scenario by as much as 16% and 13% for individual crops or tree species, respectively. This analysis affords the opportunity to consider public welfare cobenefits of a regulation that is designed to reduce carbon dioxide emissions from power plants.

  5. History of the common bean crop: its evolution beyond its areas of origin and domestication

    Directory of Open Access Journals (Sweden)

    De Ron, Antonio M.

    2016-06-01

    Full Text Available The common bean (Phaseolus vulgaris L. is the most important grain legume for direct human consumption on a global scale. Current bean germplasm collections show a wide variation of phenotypes, although genetic erosion is gradually affecting this species as in many countries local traditional varieties are being replaced by elite cultivars. This crop has spread to every continent over the past few centuries, which has resulted in a complex genetic structure of bean germplasm outside its areas of origin and domestication (South and Central America. Some evidence indicates that this germplasm is more complex than previously thought and contains additional, as yet unexplored, diversity. This is especially the case in southern Europe, particularly in the Iberian Peninsula, where it was introduced in the early sixteenth century and has been documented as a secondary focus of domestication of the species. The integration of omic data into bean germplasm documentation databases and its combination with genotypic, phenotypic and agro-ecological data is opening a new era for the enhancement and efficient use of common bean genetic resources as the main grain legume in Europe and worldwide.La judía común (Phaseolus vulgaris L. es la leguminosa de grano más relevante para el consumo humano directo en escala global. Las colecciones de germoplasma de judía actuales muestran una amplia variación de fenotipos, aunque en muchos países las variedades locales están siendo reemplazados por cultivares de élite, concentrando la producción agraria en un número cada vez más reducido de cultivares con la consecuente erosión genética o pérdida de biodiversidad. Este cultivo se ha extendido por todos los continentes durante los últimos siglos, lo que ha dado lugar a una compleja estructura genética fuera de sus áreas de origen y domesticación (Mesoamérica y Sudamérica. Diversas evidencias indican que el germoplasma europeo contiene una diversidad

  6. A Biopolymer Chitosan and Its Derivatives as Promising Antimicrobial Agents against Plant Pathogens and Their Applications in Crop Protection

    Directory of Open Access Journals (Sweden)

    Mohamed E. I. Badawy

    2011-01-01

    Full Text Available Recently, much attention has been paid to chitosan as a potential polysaccharide resource. Although several efforts have been reported to prepare functional derivatives of chitosan by chemical modifications, few attained their antimicrobial activity against plant pathogens. The present paper aims to present an overview of the antimicrobial effects, mechanisms, and applications of a biopolymer chitosan and its derivatives in crop protection. In addition, this paper takes a closer look at the physiochemical properties and chemical modifications of chitosan molecule. The recent growth in this field and the latest research papers published will be introduced and discussed.

  7. Exploring the evolution of the proteins of the plant nuclear envelope.

    Science.gov (United States)

    Poulet, Axel; Probst, Aline V; Graumann, Katja; Tatout, Christophe; Evans, David

    2017-01-02

    In this study, we explore the plasticity during evolution of proteins of the higher plant nuclear envelope (NE) from the most ancestral plant species to advanced angiosperms. The higher plant NE contains a functional Linker of Nucleoskeleton and Cytoskeleton (LINC) complex based on conserved Sad1-Unc84 (SUN) domain proteins and plant specific Klarsicht/Anc1/Syne homology (KASH) domain proteins. Recent evidence suggests the presence of a plant lamina underneath the inner membrane and various coiled-coil proteins have been hypothesized to be associated with it including Crowded Nuclei (CRWN; also termed LINC and NMCP), Nuclear Envelope Associated Protein (NEAP) protein families as well as the CRWN binding protein KAKU4. SUN domain proteins appear throughout with a key role for mid-SUN proteins suggested. Evolution of KASH domain proteins has resulted in increasing complexity, with some appearing in all species considered, while other KASH proteins are progressively gained during evolution. Failure to identify CRWN homologs in unicellular organisms included in the study and their presence in plants leads us to speculate that convergent evolution may have occurred in the formation of the lamina with each kingdom having new proteins such as the Lamin B receptor (LBR) and Lamin-Emerin-Man1 (LEM) domain proteins (animals) or NEAPs and KAKU4 (plants). Our data support a model in which increasing complexity at the nuclear envelope occurred through the plant lineage and suggest a key role for mid-SUN proteins as an early and essential component of the nuclear envelope.

  8. The fossil recordand evolution of freshwater plants: A review

    OpenAIRE

    Martín-Closas, Carles

    2003-01-01

    Palaeobotany applied to freshwater plants is an emerging field of palaeontology. Hydrophytic plants reveal evolutionary trends of their own, clearly distinct from those of the terrestrial and marine flora. During the Precambrian, two groups stand out in the fossil record of freshwater plants: the Cyanobacteria (stromatolites) in benthic environments and the prasinophytes (leiosphaeridian acritarchs) in transitional planktonic environments. During the Palaeozoic, green algae (Chlorococcales, Z...

  9. The fossil record and evolution of freshwater plants: a review /

    OpenAIRE

    Martin-Closas, Carles

    2009-01-01

    Palaeobotany applied to freshwater plants is an emerging field of palaeontology. Hydrophytic plants reveal evolutionary trends of their own, clearly distinct from those of the terrestrial and marine flora. During the Precambrian, two groups stand out in the fossil record of freshwater plants: the Cyanobacteria (stromatolites) in benthic environments and the prasinophytes (leiosphaeridian acritarchs) in transitional planktonic environments. During the Palaeozoic, green algae (Chlorococcales, Z...

  10. The Effects of Cropping Regimes on Fungal and Bacterial Communities of Wheat and Faba Bean in a Greenhouse Pot Experiment Differ between Plant Species and Compartment.

    Science.gov (United States)

    Granzow, Sandra; Kaiser, Kristin; Wemheuer, Bernd; Pfeiffer, Birgit; Daniel, Rolf; Vidal, Stefan; Wemheuer, Franziska

    2017-01-01

    Many bacteria and fungi in the plant rhizosphere and endosphere are beneficial to plant nutrient acquisition, health, and growth. Although playing essential roles in ecosystem functioning, our knowledge about the effects of multiple cropping regimes on the plant microbiome and their interactions is still limited. Here, we designed a pot experiment simulating different cropping regimes. For this purpose, wheat and faba bean plants were grown under controlled greenhouse conditions in monocultures and in two intercropping regimes: row and mixed intercropping. Bacterial and fungal communities in bulk and rhizosphere soils as well as in the roots and aerial plant parts were analyzed using large-scale metabarcoding. We detected differences in microbial richness and diversity between the cropping regimes. Generally, observed effects were attributed to differences between mixed and row intercropping or mixed intercropping and monoculture. Bacterial and fungal diversity were significantly higher in bulk soil samples of wheat and faba bean grown in mixed compared to row intercropping. Moreover, microbial communities varied between crop species and plant compartments resulting in different responses of these communities toward cropping regimes. Leaf endophytes were not affected by cropping regime but bacterial and fungal community structures in bulk and rhizosphere soil as well as fungal community structures in roots. We further recorded highly complex changes in microbial interactions. The number of negative inter-domain correlations between fungi and bacteria decreased in bulk and rhizosphere soil in intercropping regimes compared to monocultures due to beneficial effects. In addition, we observed plant species-dependent differences indicating that intra- and interspecific competition between plants had different effects on the plant species and thus on their associated microbial communities. To our knowledge, this is the first study investigating microbial communities in

  11. The Effects of Cropping Regimes on Fungal and Bacterial Communities of Wheat and Faba Bean in a Greenhouse Pot Experiment Differ between Plant Species and Compartment

    Directory of Open Access Journals (Sweden)

    Sandra Granzow

    2017-05-01

    Full Text Available Many bacteria and fungi in the plant rhizosphere and endosphere are beneficial to plant nutrient acquisition, health, and growth. Although playing essential roles in ecosystem functioning, our knowledge about the effects of multiple cropping regimes on the plant microbiome and their interactions is still limited. Here, we designed a pot experiment simulating different cropping regimes. For this purpose, wheat and faba bean plants were grown under controlled greenhouse conditions in monocultures and in two intercropping regimes: row and mixed intercropping. Bacterial and fungal communities in bulk and rhizosphere soils as well as in the roots and aerial plant parts were analyzed using large-scale metabarcoding. We detected differences in microbial richness and diversity between the cropping regimes. Generally, observed effects were attributed to differences between mixed and row intercropping or mixed intercropping and monoculture. Bacterial and fungal diversity were significantly higher in bulk soil samples of wheat and faba bean grown in mixed compared to row intercropping. Moreover, microbial communities varied between crop species and plant compartments resulting in different responses of these communities toward cropping regimes. Leaf endophytes were not affected by cropping regime but bacterial and fungal community structures in bulk and rhizosphere soil as well as fungal community structures in roots. We further recorded highly complex changes in microbial interactions. The number of negative inter-domain correlations between fungi and bacteria decreased in bulk and rhizosphere soil in intercropping regimes compared to monocultures due to beneficial effects. In addition, we observed plant species-dependent differences indicating that intra- and interspecific competition between plants had different effects on the plant species and thus on their associated microbial communities. To our knowledge, this is the first study investigating

  12. Importance of Genetic Diversity Assessment in Crop Plants and Its Recent Advances: An Overview of Its Analytical Perspectives

    Directory of Open Access Journals (Sweden)

    M. Govindaraj

    2015-01-01

    Full Text Available The importance of plant genetic diversity (PGD is now being recognized as a specific area since exploding population with urbanization and decreasing cultivable lands are the critical factors contributing to food insecurity in developing world. Agricultural scientists realized that PGD can be captured and stored in the form of plant genetic resources (PGR such as gene bank, DNA library, and so forth, in the biorepository which preserve genetic material for long period. However, conserved PGR must be utilized for crop improvement in order to meet future global challenges in relation to food and nutritional security. This paper comprehensively reviews four important areas; (i the significance of plant genetic diversity (PGD and PGR especially on agriculturally important crops (mostly field crops; (ii risk associated with narrowing the genetic base of current commercial cultivars and climate change; (iii analysis of existing PGD analytical methods in pregenomic and genomic era; and (iv modern tools available for PGD analysis in postgenomic era. This discussion benefits the plant scientist community in order to use the new methods and technology for better and rapid assessment, for utilization of germplasm from gene banks to their applied breeding programs. With the advent of new biotechnological techniques, this process of genetic manipulation is now being accelerated and carried out with more precision (neglecting environmental effects and fast-track manner than the classical breeding techniques. It is also to note that gene banks look into several issues in order to improve levels of germplasm distribution and its utilization, duplication of plant identity, and access to database, for prebreeding activities. Since plant breeding research and cultivar development are integral components of improving food production, therefore, availability of and access to diverse genetic sources will ensure that the global food production network becomes more

  13. Sinapate esters in brassicaceous plants: biochemistry, molecular biology, evolution and metabolic engineering.

    Science.gov (United States)

    Milkowski, Carsten; Strack, Dieter

    2010-06-01

    Brassicaceous plants are characterized by a pronounced metabolic flux toward sinapate, produced by the shikimate/phenylpropanoid pathway, which is converted into a broad spectrum of O-ester conjugates. The abundant sinapate esters in Brassica napus and Arabidopsis thaliana reflect a well-known metabolic network, including UDP-glucose:sinapate glucosyltransferase (SGT), sinapoylglucose:choline sinapoyltransferase (SCT), sinapoylglucose:L-malate sinapoyltransferase (SMT) and sinapoylcholine (sinapine) esterase (SCE). 1-O-Sinapoylglucose, produced by SGT during seed development, is converted to sinapine by SCT and hydrolyzed by SCE in germinating seeds. The released sinapate feeds via sinapoylglucose into the biosynthesis of sinapoylmalate in the seedlings catalyzed by SMT. Sinapoylmalate is involved in protecting the leaves against the deleterious effects of UV-B radiation. Sinapine might function as storage vehicle for ready supply of choline for phosphatidylcholine biosynthesis in young seedlings. The antinutritive character of sinapine and related sinapate esters hamper the use of the valuable seed protein of the oilseed crop B. napus for animal feed and human nutrition. Due to limited variation in seed sinapine content within the assortment of B. napus cultivars, low sinapine lines cannot be generated by conventional breeding giving rise to genetic engineering of sinapate ester metabolism as a promising means. In this article we review the progress made throughout the last decade in identification of genes involved in sinapate ester metabolism and characterization of the encoded enzymes. Based on gene structures and enzyme recruitment, evolution of sinapate ester metabolism is discussed. Strategies of targeted metabolic engineering, designed to generate low-sinapate ester lines of B. napus, are evaluated.

  14. Why do smallholders plant biofuel crops? The ‘politics of consent’ in Mexico

    NARCIS (Netherlands)

    Castellanos-Navarrete, Antonio; Jansen, Kees

    2017-01-01

    Recent studies have addressed the social and environmental impacts of biofuel crops but seldom the question as to why rural producers engage in their production. It is particularly unclear how governments worldwide, especially in middle-income countries such as Brazil, Thailand, and Mexico, could

  15. Plant effects on biological control of spider mites in the ornamental crop gerbera

    NARCIS (Netherlands)

    Krips, O.E.

    2000-01-01

    Introduction

    The spider mite Tetranychus urticae Koch is an important pest in many greenhouse crops. In vegetables it can be successfully controlled with the predatory mite Phytoseiulus persimilis

  16. Response of Crops to Limited Water: Understanding and Modeling Water Stress Effects on Plant Growth Processes

    Science.gov (United States)

    The semi-arid regions of western U.S., India, China, and other parts of the world produce a major portion of the world’s food and fiber needs—from staple food grains of wheat, rice, and corn, to vegetables, fruits, nuts, wine, cotton, and forage crops for cattle and poultry. Most of this production ...

  17. Vertical Distribution of the Plant-Parasitic Nematode, Pratylenchus penetrans, Under Four Field Crops

    NARCIS (Netherlands)

    Pudassaini, M.P.; Schomaker, C.H.; Been, T.H.; Moens, M.

    2006-01-01

    The vertical distribution of Pratylenchus penetrans was monitored in four fields cropped with maize, black salsify, carrot, or potato. Soil samples were collected at 21-day intervals from May 2002 until April 2003 from five plots (2 × 5 m(^2)) per field. Per plot, 15 cores were taken to a depth of

  18. Integrated soil and plant phosphorus management for crop and environment in China

    NARCIS (Netherlands)

    Li, H.; Huang, G.; Meng, Q.; Ma, L.; Yuan, L.; Wang, F.; Zhang, W.; Cui, Z.; Shen, J.; Chen, X.; Jiang, R.; Zhang, F.

    2011-01-01

    Crop production in China has been greatly improved by increasing phosphorus (P) fertilizer input, but overuse of P by farmers has caused low use efficiency, increasing environmental risk and accumulation of P in soil. From 1980 to 2007, average 242 kg P ha-1 accumulated in soil, resulting in average

  19. A dialogue on interdisciplinary collaboration to bridge the gap between plant genomics and crop sciences

    NARCIS (Netherlands)

    Struik, P.C.; Cassman, K.G.; Koornneef, M.

    2007-01-01

    In the future, more food needs to be produced with increasingly scarce natural resources. Genomics can play a key role in accelerating yield gains because it helps to improve our understanding ofgenetic traits and assists in breeding for better crop performance. The scientific muscle of

  20. Developing robust crop plants for sustaining growth and yield under adverse climatic changes

    Science.gov (United States)

    Agricultural production and quality are expected to suffer from adverse changes in climatic conditions, including global warming, and this will affect worldwide human and animal food security. Global warming has been shown to negatively impact crop yield and therefore will affect sustainability of a...

  1. Plant adaptation to acid soils: the molecular basis for crop aluminum resistance

    Science.gov (United States)

    Aluminum (Al) toxicity on acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world’s potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to ...

  2. Effects of Plant Density and Water Stress on Competitive Ability and Yield of Medicago Sativa L. and Bromus tomentellus Boiss.in Mono and Mixed Cropping

    Directory of Open Access Journals (Sweden)

    S. Barati

    2016-03-01

    Full Text Available The effects of plant density and water stress on yield of Medicago sativa and Bromus tomentellus was studied. A greenhouse experiment was conducted at Isfahan University of Technology in 2013. The experiment included 18 treatments, three crop compositions (M.sativa, B. tomentellus or mixture of the two, two plant density levels, three watering regimes and four replicates, arranged in a completely randomized block design. Results showed that total yield of M. sativa mono-cropping was higher than mixed cropping and it was higher than B. tomentellus mono-cropping. Land Equivalent Ratio (LER values were less than 1 for all mixed cropping treatments, indicated the interspecific competition in mixed cropping. The biomass production per plant decreased with increasing density, competition for resource utilization and water stress. Compare of above-ground and below-ground dry matter showed that M. sativa appeared to be more constrained by intraspecific than by interspecific competition, Conversely, B. tomentellus was more suppressed by interspecific competition exerted by M. sativa than by intraspecific competition. Relative competition intensity (RCI values were positive for B. tomentellus and negative for M.sativa, implying that competitive ability of M.sativa was higher than B. tomentellus in mixed cropping .

  3. Caesium-137 soil-to-plant transfer for representative agricultural crops of monocotyledonous and dicotyledonous plants in post-Chernobyl steppe landscape

    Science.gov (United States)

    Paramonova, Tatiana; Komissarova, Olga; Turykin, Leonid; Kuzmenkova, Natalia; Belyaev, Vladimir

    2016-04-01

    The accident at the Chernobyl nuclear power plant in 1986 had a large-scale action on more than 2.3 million hectares agricultural lands in Russia. The area of radioactively contaminated chernozems of semi-arid steppe zone with initial levels of Cs-137 185-555 kBq/m2 in Tula region received the name "Plavsky radioactive hotspot". Nowadays, after the first half-life period of Cs-137 arable chernozems of the region are still polluted with 3-6-fold excess above the radioactive safety standard (126-228 kBq/m2). Therefore, qualitative and quantitative characteristics of Cs-137 soil-to-plant transfer are currently a central problem for land use on the territory. The purpose of the present study was revealing the biological features of Cs-137 root uptake from contaminated arable chernozems by different agricultural crops. The components of a grass mixture growing at the central part of Plavsky radioactive hotspot with typical dicotyledonous and monocotyledonous plants - galega (Galega orientalis, Fabaceae family) and bromegrass (Bromus inermis, Gramineae family) respectively - were selected for the investigation, that was conducted during the period of harvesting in 2015. An important point was that the other factors influenced on Cs-137 soil-to-plant transfer - the level of soil pollution, soil properties, climatic conditions, vegetative phase, etc. - were equal. So, biological features of Cs-137 root uptake could be estimated the most credible manner. As a whole, general discrimination of Cs-137 root uptake was clearly shown for both agricultural crops. Whereas Cs-137 activity in rhizosphere 30-cm layer of arable chernozem was 371±74 Bq/kg (140±32 kBq/m2), Cs-137 activities in plant biomass were one-two orders of magnitude less, and transfer factor (TF) values (the ratio of the Cs-137 activities in vegetation and in soil) not exceeded 0.11. At the same time bioavailability of Cs-137 for bromegrass was significantly higher than for galega: TFs in total biomass of the

  4. Multitrophic effects of plant resistance: from basic ecology to application in transgenic crops

    NARCIS (Netherlands)

    Kos, M.

    2012-01-01

    Plants have evolved a wide array of direct and indirect resistance traits that prevent or reduce herbivory by insects. The aim of this thesis was to study the effects of direct and indirect plant resistance traits on the multitrophic interactions between brassicaceous plants, leaf-chewing and

  5. Plant growth regulation in seed crops of perennial ryegrass (Lolium perenne L)

    DEFF Research Database (Denmark)

    Boelt, Birte; Lemaire, Charles; Abel, Simon

    2016-01-01

    Seed yield components were recorded in plants of perennial ryegrass cv. Calibra a medium late, forage type (4n) in a two factorial block design with Nitrogen (N) and plant growth regulator (PGR) application in 2014 and 2015 at Aarhus University (AU), Flakkebjerg. For each plant, reproductive...

  6. Discovering ways to improve crop production and plant quality [Chapter 17

    Science.gov (United States)

    Kim M. Wilkinson

    2009-01-01

    Working with plants is a process of discovery. Being curious and aware, paying close attention, and staying open and adaptive are important practices. Books and people can help us learn about plants in the nursery, but the very best teachers are the plants themselves. "Research" is simply paying close attention, tracking what is happening and what is causing...

  7. Evolution of Plant Parasitism in the Phylum Nematoda

    NARCIS (Netherlands)

    Quist, C.W.; Smant, G.; Helder, J.

    2015-01-01

    Within the species-rich and trophically diverse phylum Nematoda, at least four independent major lineages of plant parasites have evolved, and in at least one of these major lineages plant parasitism arose independently multiple times. Ribosomal DNA data, sequence information from nematode-produced,

  8. Keystone Herbivores and the Evolution of Plant Defenses

    NARCIS (Netherlands)

    Poelman, Erik H.; Kessler, André

    2016-01-01

    Plants need to defend themselves against a diverse and dynamic herbivore community. Such communities may be shaped by keystone herbivores that through their feeding alter the plant phenotype as well as the likelihood of attack by other herbivores. Here, we discuss such herbivores that have a

  9. A review of plant-pharmaceutical interactions: from uptake and effects in crop plants to phytoremediation in constructed wetlands

    DEFF Research Database (Denmark)

    Carvalho, Pedro N; Basto, M Clara P; Almeida, C Marisa R

    2014-01-01

    the potential impact of veterinary and human pharmaceuticals on arable land. However, plant uptake as well as phytotoxicity data are scarcely studied. Simultaneously, phytoremediation as a tool for pharmaceutical removal from soils, sediments and water is starting to be researched, with promising results....... This review gives an in-depth overview of the phytotoxicity of pharmaceuticals, their uptake and their removal by plants. The aim of the current work was to map the present knowledge concerning pharmaceutical interactions with plants in terms of uptake and the use of plant-based systems for phytoremediation...

  10. 75 FR 65423 - Crop Assistance Program

    Science.gov (United States)

    2010-10-25

    ..., for a producer ] in a disaster county as of October 22, 2010. Subsequent crops, replacement crops.... Replacement crop means the planting or approved prevented planting of any crop for harvest following the... cotton, soybeans, or sweet potatoes not in a recognized double- cropping sequence. Replacement crops are...

  11. Host plant resistance to aphids in cultivated crops: genetic and molecular bases, and interactions with aphid populations.

    Science.gov (United States)

    Dogimont, Catherine; Bendahmane, Abdelhafid; Chovelon, Véronique; Boissot, Nathalie

    2010-01-01

    Host plant resistance is an efficient and environmentally friendly means of controlling insects, including aphids, but resistant-breaking biotypes have occurred in several plant-aphid systems. Our review of the genetic and molecular bases of aphid resistance in crop species emphasizes the limited number of aphid resistance genes and alleles. Inheritance of aphid resistance may be monogenic (dominant or recessive genes) or polygenic. Two dominant, aphid resistance genes have been isolated to date. They both encode NBS-LRR proteins involved in the specific recognition of aphids. Strategies to ensure aphid resistance effectiveness and durability are discussed. Innovative research activities are proposed. Copyright 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  12. Chemodiversity in Selaginella: a reference system for parallel and convergent metabolic evolution in terrestrial plants

    Directory of Open Access Journals (Sweden)

    Jing-Ke eWeng

    2013-05-01

    Full Text Available Early plants began colonizing the terrestrial earth approximately 450 million years ago. Their success on land has been partially attributed to the evolution of specialized metabolic systems from core metabolic pathways, the former yielding structurally and functionally diverse chemicals to cope with a myriad of biotic and abiotic pressures. Over the past two decades, functional genomics, primarily focused on flowering plants, has begun cataloging the biosynthetic players underpinning assorted classes of plant specialized metabolites. However, the molecular mechanisms enriching specialized metabolic pathways during land plant evolution remain largely unexplored. Selaginella is an extant lycopodiophyte genus representative of an ancient lineage of tracheophytes. Notably, the lycopodiophytes diverged from euphyllophytes over 400 million years ago. The recent completion of the whole-genome sequence of an extant lycopodiophyte, Selaginella moellendorffii, provides new genomic and biochemical resources for studying metabolic evolution in vascular plants. 400 million years of independent evolution of lycopodiophytes and euphyllophytes resulted in numerous metabolic traits confined to each lineage. Surprisingly, a cadre of specialized metabolites, generally accepted to be restricted to seed plants, have been identified in Selaginella. Initial work suggested that Selaginella lacks obvious catalytic homologues known to be involved in the biosynthesis of well-studied specialized metabolites in seed plants. Therefore, these initial functional analyses suggest that the same chemical phenotypes arose independently more commonly than anticipated from our conventional understanding of divergent evolution of metabolism. Notably, the emergence of analogous and homologous catalytic machineries through convergent and parallel evolution, respectively, seems to have occurred repeatedly in different plant lineages.

  13. Promiscuity, impersonation and accommodation: evolution of plant specialized metabolism.

    Science.gov (United States)

    Leong, Bryan J; Last, Robert L

    2017-12-01

    Specialized metabolic enzymes and metabolite diversity evolve through a variety of mechanisms including promiscuity, changes in substrate specificity, modifications of gene expression and gene duplication. For example, gene duplication and substrate binding site changes led to the evolution of the glucosinolate biosynthetic enzyme, AtIPMDH1, from a Leu biosynthetic enzyme. BAHD acyltransferases illustrate how enzymatic promiscuity leads to metabolite diversity. The examples 4-coumarate:CoA ligase and aromatic acid methyltransferases illustrate how promiscuity can potentiate the evolution of these specialized metabolic enzymes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Flexible Coal: Evolution from Baseload to Peaking Plant (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, J.; Lew, D.; Kumar, N.

    2013-12-01

    Twenty-first century power systems, with higher penetration levels of low-carbon energy, smart grids, and other emerging technologies, will favor resources that have low marginal costs and provide system flexibility (e.g., the ability to cycle on and off to follow changes in variable renewable energy plant output). Questions remain about both the fate of coal plants in this scenario and whether they can cost-effectively continue to operate if they cycle routinely. The experience from the CGS plant demonstrates that coal plants can become flexible resources. This flexibility - namely the ability to cycle on and off and run at lower output (below 40% of capacity) - requires limited hardware modifications but extensive modifications to operational practice. Cycling does damage the plant and impact its life expectancy compared to baseload operations. Nevertheless, strategic modifications, proactive inspections and training programs, among other operational changes to accommodate cycling, can minimize the extent of damage and optimize the cost of maintenance. CGS's cycling, but not necessarily the associated price tag, is replicable. Context - namely, power market opportunities and composition of the generation fleet - will help determine for other coal plants the optimal balance between the level of cycling-related forced outages and the level of capital investment required to minimize those outages. Replicating CGS's experience elsewhere will likely require a higher acceptance of forced outages than regulators and plant operators are accustomed to; however, an increase in strategic maintenance can minimize the impact on outage rates.

  15. Effect of integrated approach of plant nutrients on yield and yield attributes of different crops in wheat-sesame-T. Aman cropping pattern

    Directory of Open Access Journals (Sweden)

    M.A. Islam

    2013-12-01

    Full Text Available The experiment was carried out at FSRD site, Pushpopara, Pabna, during November, 2010 to December, 2011 to observe the comparative performance of integrated plant nutrients management (IPNS system through the use of organic (cowdung, cowdung slurry manure and inorganic fertilizer on wheat, sesame and T. Aman crops under wheat-sesame-T. Aman cropping pattern. The experiment was consisted with four treatments viz. T1: Soil test based inorganic fertilizer dose for high yield goal, T2: Cowdung @ 5 t ha-1 + IPNS basis inorganic fertilizer dose for high yield goal, T3: Cowdung slurry @ 5 t ha-1 + IPNS basis inorganic fertilizer dose for high yield goal and T4: Fertilizer dose usually practiced by the farmers. In case of wheat, the highest grain yield (3.80 t ha-1 was obtained from bio-slurry treated plot that means T3 treatment followed by T2 and the lowest (3.31 t ha-1 from T4. Higher seed yield (1.31 t ha-1 of sesame was obtained from T3 that was statistically identical to T2 and T1 and the lower (1.01 t ha-1 from T4. For T. Aman rice, the highest grain yield (4.89 t ha-1 was obtained from T3 which was statistically indistinguishable from T1 where as the lowest grain yield (4.1 t ha-1 was recorded from T4. Considering the whole pattern, it is observed that the highest gross return (271100 Tk ha-1 was obtained from T3 followed by T2 and the lowest (225650 Tk ha-1 from T1 treatment. Total variable cost was recorded as the highest (100368 Tk ha-1 in T2 followed by T3 and the lowest (86775 Tk ha-1 in T4 treatment. The highest marginal value of product (45450 Tk ha-1 was recorded in T3 followed by T2 where as the minimum (28710 Tk ha-1 was found in T1 over the T4 treatment. Marginal variable cost was observed as the highest (13593 Tk ha-1 in T2 treatment followed by T3 and the minimum (8899 Tk ha-1 was recorded in T1 treatment. The highest MBCR (4.15 was recorded from T3 followed by T2 and the minimum (2.31 from T2 treatment.

  16. Cloning plants by seeds: Inheritance models and candidate genes to increase fundamental knowledge for engineering apomixis in sexual crops.

    Science.gov (United States)

    Pupilli, Fulvio; Barcaccia, Gianni

    2012-06-30

    Apomixis is desirable in agriculture as a reproductive strategy for cloning plants by seeds. Because embryos derive from the parthenogenic development of apomeiotic egg cells, apomixis excludes fertilization in addition to meiotic segregation and recombination, resulting in offspring that are exact replicas of the parent. Introgression of apomixis from wild relatives to crop species and transformation of sexual genotypes into apomictically reproducing ones are long-held goals of plant breeding. In fact, it is generally accepted that the introduction of apomixis into agronomically important crops will have revolutionary implications for agriculture. This review deals with the current genetic and molecular findings that have been collected from model species to elucidate the mechanisms of apomeiosis, parthenogenesis and apomixis as a whole. Our goal is to critically determine whether biotechnology can combine key genes known to control the expression of the processes miming the main components of apomixis in plants. Two natural apomicts, as the eudicot Hypericum perforatum L. (St. John's wort) and the monocot Paspalum spp. (crowngrass), and the sexual model species Arabidopsis thaliana are ideally suited for such investigations at the genomic and biotechnological levels. Some novel views and original concepts have been faced on this review, including (i) the parallel between Y-chromosome and apomixis-bearing chromosome (e.g., comparative genomic analyses revealed common features as repression of recombination events, accumulation of transposable elements and degeneration of genes) from the most primitive (Hypericum-type) to the most advanced (Paspalum-type) in evolutionary terms, and (ii) the link between apomixis and gene-specific silencing mechanisms (i.e., likely based on chromatin remodelling factors), with merging lines of evidence regarding the role of auxin in cell fate specification of embryo sac and egg cell development in Arabidopsis. The production of

  17. Leaf blade and petiole nutritional evolution and variability throughout the crop season for Vitis vinifera L. cv. Graciano

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez, N.; García-Escudero, N.; Romero, I.; Benito, A.; Martín, I.

    2015-07-01

    An adequate nutritional state of a crop can be kept by means of a well-designed fertilization plan based on the assessment of the nutrient availability throughout the growing season. The objective of this study was to determine the reliability of leaf blade and petiole diagnosis and the period of validity of their references at both flowering and veraison by means of systematic monitoring throughout the complete growing season. The study was carried out in two plots planted with Vitis vinifera L. cv. Graciano within the AOC Rioja (Spain). Blades and petioles were collected throughout a growing season (2006) and total N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B concentrations were analyzed in both tissues. Results suggest, in general, that petioles have higher variability and lower analysis reproducibility than blades. Therefore, blade could be a more appropriate tissue to evaluate N, P, K, Ca, and Mg at both flowering and veraison in this variety. Micronutrients in blade and petiole showed different variability behaviour in each of the vineyards studied, therefore, based on our results, it was difficult to determine which one could be the best tissue for the nutritional diagnosis of the ‘Graciano’ variety. Seasonal changes of nutrient concentration in both tissues also confirmed the need for reference values for each tissue and each phenological stage. (Author)

  18. Plant genetic resources: What can they contribute toward increased crop productivity?

    OpenAIRE

    Hoisington, David; Khairallah, Mireille; Reeves, Timothy; Ribaut, Jean-Marcel; Skovmand, Bent; Taba, Suketoshi; Warburton, Marilyn

    1999-01-01

    To feed a world population growing by up to 160 people per minute, with >90% of them in developing countries, will require an astonishing increase in food production. Forecasts call for wheat to become the most important cereal in the world, with maize close behind; together, these crops will account for ≈80% of developing countries’ cereal import requirements. Access to a range of genetic diversity is critical to the success of breeding programs. The global effort...

  19. Plant water use efficiency over geological time--evolution of leaf stomata configurations affecting plant gas exchange.

    Directory of Open Access Journals (Sweden)

    Shmuel Assouline

    Full Text Available Plant gas exchange is a key process shaping global hydrological and carbon cycles and is often characterized by plant water use efficiency (WUE - the ratio of CO2 gain to water vapor loss. Plant fossil record suggests that plant adaptation to changing atmospheric CO2 involved correlated evolution of stomata density (d and size (s, and related maximal aperture, amax . We interpreted the fossil record of s and d correlated evolution during the Phanerozoic to quantify impacts on gas conductance affecting plant transpiration, E, and CO2 uptake, A, independently, and consequently, on plant WUE. A shift in stomata configuration from large s-low d to small s-high d in response to decreasing atmospheric CO2 resulted in large changes in plant gas exchange characteristics. The relationships between gas conductance, gws , A and E and maximal relative transpiring leaf area, (amax ⋅d, exhibited hysteretic-like behavior. The new WUE trend derived from independent estimates of A and E differs from established WUE-CO2 trends for atmospheric CO2 concentrations exceeding 1,200 ppm. In contrast with a nearly-linear decrease in WUE with decreasing CO2 obtained by standard methods, the newly estimated WUE trend exhibits remarkably stable values for an extended geologic period during which atmospheric CO2 dropped from 3,500 to 1,200 ppm. Pending additional tests, the findings may affect projected impacts of increased atmospheric CO2 on components of the global hydrological cycle.

  20. Growth response of maize plants (Zea mays L.) to wheat and lentil pre-cropping and to indigenous mycorrhizal in field soil

    Energy Technology Data Exchange (ETDEWEB)

    Almaca, A.; Ortas, I.

    2010-07-01

    The presence of indigenous mycorrhizal fungi may have significant effects on the growth and on the root morphology of plants, under arid and semi arid soil conditions. Lentil and wheat are the traditional crops grown in Southeastern Turkey. In this study soil samples from the Harran plain were collected from the 0-15 cm surface layer under wheat or lentil crop residues and used in a pot experiment carried out under greenhouse conditions with four levels of P fertilization: 0, 20, 40 and 80 mg kg{sup -}1 soil as Ca(H{sub 2}PO{sub 4}){sub 2}. Half of the soil batches were submitted to a heating treatment (80 degree centigrade, 2 h). The maize variety PX-9540 was grown in the pots for 57 days. At harvest, plant dry weight, root length, P and Zn concentrations in plant tissues were measured and the extent of root colonization by arbuscular mycorrhizal fungi (AMF) was determined. Results showed that maize plants grown in soils where lentil had been previously cultivated grew better than those grown after wheat cultivation. In both cases, P concentration in plant tissues increased with increased P fertilization. There were no significant differences in root AMF colonization between soils with different crop sequences, nor with soils submitted to high temperature. Previous crops had a significant influence on the growth of plants that could be related to differences in the indigenous mycorrhizas inoculum potential and efficacy that can promote P uptake and benefit plant growth. (Author) 29 refs.

  1. Optimizing experimental procedures for quantitative evaluation of crop plant performance in high throughput phenotyping systems

    National Research Council Canada - National Science Library

    Junker, Astrid; Muraya, Moses M; Weigelt-Fischer, Kathleen; Arana-Ceballos, Fernando; Klukas, Christian; Melchinger, Albrecht E; Meyer, Rhonda C; Riewe, David; Altmann, Thomas

    2015-01-01

    Detailed and standardized protocols for plant cultivation in environmentally controlled conditions are an essential prerequisite to conduct reproducible experiments with precisely defined treatments...

  2. Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management.

    Science.gov (United States)

    Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

    2015-01-01

    Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3(-)-N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha(-1) biomass, whereas mixtures averaged 4.1 Mg ha(-1) and hairy vetch 2.3 Mg ha(-1). Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha(-1) N and had mean C:N ratio Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures.

  3. Plant evolution at the interface of paleontology and developmental biology: An organism-centered paradigm.

    Science.gov (United States)

    Rothwell, Gar W; Wyatt, Sarah E; Tomescu, Alexandru M F

    2014-06-01

    Paleontology yields essential evidence for inferring not only the pattern of evolution, but also the genetic basis of evolution within an ontogenetic framework. Plant fossils provide evidence for the pattern of plant evolution in the form of transformational series of structure through time. Developmentally diagnostic structural features that serve as "fingerprints" of regulatory genetic pathways also are preserved by plant fossils, and here we provide examples of how those fingerprints can be used to infer the mechanisms by which plant form and development have evolved. When coupled with an understanding of variations and systematic distributions of specific regulatory genetic pathways, this approach provides an avenue for testing evolutionary hypotheses at the organismal level that is analogous to employing bioinformatics to explore genetics at the genomic level. The positions where specific genes, gene families, and developmental regulatory mechanisms first appear in phylogenies are correlated with the positions where fossils with the corresponding structures occur on the tree, thereby yielding testable hypotheses that extend our understanding of the role of developmental changes in the evolution of the body plans of vascular plant sporophytes. As a result, we now have new and powerful methodologies for characterizing major evolutionary changes in morphology, anatomy, and physiology that have resulted from combinations of genetic regulatory changes and that have produced the synapomorphies by which we recognize major clades of plants. © 2014 Botanical Society of America, Inc.

  4. A new grading system for plant-available potassium using exhaustive cropping techniques combined with chemical analyses of soils

    Science.gov (United States)

    Li, Ting; Wang, Huoyan; Zhou, Zijun; Chen, Xiaoqin; Zhou, Jianmin

    2016-11-01

    A new grading system for plant-available potassium (K) in soils based on K release rate from soils and plant growth indices was established. In the study, fourteen different agricultural soils from the southern subtropical to the northern temperate zones in China were analyzed by both chemical extraction methods and exhaustive cropping techniques. Based on the change trends in plant growth indices, relative biomass yields of 70% and 50%, K-deficient coefficients of 35 and 22 under conventional exhaustive experiments, and tissue K concentrations of 40 g kg-1 and 15 g kg-1 under intensive exhaustive experiments were obtained as critical values that represent different change trends. In addition, the extraction method using 0.2 mol L-1 sodium tetraphenylboron (NaTPB) suggested soil K release rates of 12 mg kg-1 min-1 and 0.4 mg kg-1 min-1 as turning points that illustrated three different release trends. Thus, plant-available K in soils was classified into three categories: high available K, medium available K and low available K, and grading criteria and measurement methods were also proposed. This work has increased our understanding of soil K bioavailability and has direct application in terms of routine assessment of agriculture soils.

  5. Evolution of the YABBY gene family in seed plants.

    Science.gov (United States)

    Finet, Cédric; Floyd, Sandra K; Conway, Stephanie J; Zhong, Bojian; Scutt, Charles P; Bowman, John L

    2016-01-01

    Members of the YABBY gene family of transcription factors in angiosperms have been shown to be involved in the initiation of outgrowth of the lamina, the maintenance of polarity, and establishment of the leaf margin. Although most of the dorsal-ventral polarity genes in seed plants have homologs in non-spermatophyte lineages, the presence of YABBY genes is restricted to seed plants. To gain insight into the origin and diversification of this gene family, we reconstructed the evolutionary history of YABBY gene lineages in seed plants. Our findings suggest that either one or two YABBY genes were present in the last common ancestor of extant seed plants. We also examined the expression of YABBY genes in the gymnosperms Ephedra distachya (Gnetales), Ginkgo biloba (Ginkgoales), and Pseudotsuga menziesii (Coniferales). Our data indicate that some YABBY genes are expressed in a polar (abaxial) manner in leaves and female cones in gymnosperms. We propose that YABBY genes already acted as polarity genes in the last common ancestor of extant seed plants. © 2016 Wiley Periodicals, Inc.

  6. Plant expansins in bacteria and fungi: evolution by horizontal gene transfer and independent domain fusion.

    Science.gov (United States)

    Nikolaidis, Nikolas; Doran, Nicole; Cosgrove, Daniel J

    2014-02-01

    Horizontal gene transfer (HGT) has been described as a common mechanism of transferring genetic material between prokaryotes, whereas genetic transfers from eukaryotes to prokaryotes have been rarely documented. Here we report a rare case of HGT in which plant expansin genes that code for plant cell-wall loosening proteins were transferred from plants to bacteria, fungi, and amoebozoa. In several cases, the species in which the expansin gene was found is either in intimate association with plants or is a known plant pathogen. Our analyses suggest that at least two independent genetic transfers occurred from plants to bacteria and fungi. These events were followed by multiple HGT events within bacteria and fungi. We have also observed that in bacteria expansin genes have been independently fused to DNA fragments that code for an endoglucanase domain or for a carbohydrate binding module, pointing to functional convergence at the molecular level. Furthermore, the functional similarities between microbial expansins and their plant xenologs suggest that these proteins mediate microbial-plant interactions by altering the plant cell wall and therefore may provide adaptive advantages to these species. The evolution of these nonplant expansins represents a unique case in which bacteria and fungi have found innovative and adaptive ways to interact with and infect plants by acquiring genes from their host. This evolutionary paradigm suggests that despite their low frequency such HGT events may have significantly contributed to the evolution of prokaryotic and eukaryotic species.

  7. Fructan biosynthesis in crop plants : the molecular regulation of fructan biosynthesis in chicory (Cichorium intybus L.)

    NARCIS (Netherlands)

    Arkel, van J.

    2013-01-01

    Fructan is a polymer of fructose produced by plants and microorganisms. Within the plant kingdom about 45.000 species accumulate fructan as storage carbohydrate in addition to, or instead of, starch. Fructan accumulating species are mainly found in temperate and sub-tropical regions with seasonal or

  8. In vitro culture of higher plants as a tool in the propagation of horticultural crops.

    NARCIS (Netherlands)

    Pierik, R.L.M.

    1988-01-01

    In vitro culture of higher plants is the culture, under sterile conditions, of plants, seeds, embryos, organs, explants, tissues, cells and protoplasts on nutrient media. This type of culture has shown spectacular development since 1975, resulting in the production and regeneration of viable

  9. ADVANCES IN THE APPLICATION OF REMOTE SENSING TO PLANT INCORPORATED PROTECTANT CROP MONITORING

    Science.gov (United States)

    Current forecasts call for significant increases to the plantings of transgenic corn in the United States for the 2007 growing season and beyond. Transgenic acreage approaching 80% of the total corn plantings could be realized by 2009. These conditions call for a new approach to ...

  10. Secondary School Students' and Their Parents' Knowledge and Interest in Crop Plants: Why Should We Care?

    Science.gov (United States)

    Fritsch, Eva-Maria; Dreesmann, Daniel C.

    2015-01-01

    While there is increasing world-wide discussion of the importance of renewable biological resources and a bio-based economy, science educators around the world have become aware of a declining general interest in plants and agriculture and of little knowledge of plants among the public. Recently, there have been few systematic investigations on…

  11. Study of laticiferous (latex-bearing) plants as potential petro-crops

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, V.K.; Garg, V.K.; Gupta, Y.K.; Rawat, S.S.; Singh, J.; Srivastava, G.S.

    1983-08-01

    While examining the possibility of using renewable plant materials as sources of hydrocarbons, indigenous laticiferous plants belonging to the families of Asclepiadaceae, Apocynaceae, Moraceae and Convolvulaceae have been evaluated. A few potential species have been selected as potential sources. Final selection can be made when biomass data on each of these are available.

  12. The Exogenous Amelioration Roles of Growth Regulators on Crop Plants Grow under Different Osmotic Potential

    Directory of Open Access Journals (Sweden)

    Hamdia M. Abd El-Samad

    2014-03-01

    Full Text Available The production of fresh and dry matter of maize, wheat, cotton, broad and parsley plants show a variable response to the elevation of salinity stress. The production of fresh and dry matter of shoots and roots in wheat and broad bean plants tended to decrease with increasing NaCl concentration, salt stress progressively decrease in fresh and dry matter yield of maize plants. The increase in salinization levels induced a general insignificant change in production of fresh and dry matter of both organs of parsley plants. However, salinity induced a marked increase in the values of fresh and dry matter yields of cotton plants grown at the lowest level (-0.3 MPa NaCl and a reduction at higher salinization levels. Leaf area of unsprayed plants was excesivly decreased with the rise of osmotic stress levels especially at higher salinity levels of maize, wheat, cotton, and broad bean and parsley plants. the total pigments concentration decreased with rise of salinization levels in maize and cotton, these contents remained more or less un affected up to the level of 0.6 MPa NaCl in wheat and up to 0.9 MPa in parsley plants, there above, they were significantly reduced with increasing salinity levels. In broad bean plants the total pigments contents showed a non-significant alterations at all salinity stress. Spraying the vegetative parts of the five tested plants with 200 ppm of either GA3 or kinetin completely ameliorated the deleterious effect of salinity in fresh, dry matter, leaf area and pigment contents.

  13. Salicornia as a crop plant in temperate regions: selection of genetically characterized ecotypes and optimization of their cultivation conditions.

    Science.gov (United States)

    Singh, Devesh; Buhmann, Anne K; Flowers, Tim J; Seal, Charlotte E; Papenbrock, Jutta

    2014-11-10

    Rising sea levels and salinization of groundwater due to global climate change result in fast-dwindling sources of freshwater. Therefore, it is important to find alternatives to grow food crops and vegetables. Halophytes are naturally evolved salt-tolerant plants that are adapted to grow in environments that inhibit the growth of most glycophytic crop plants substantially. Members of the Salicornioideae are promising candidates for saline agriculture due to their high tolerance to salinity. Our aim was to develop genetically characterized lines of Salicornia and Sarcocornia for further breeding and to determine optimal cultivation conditions. To obtain a large and diverse genetic pool, seeds were collected from different countries and ecological conditions. The external transcribed spacer (ETS) sequence of 62 Salicornia and Sarcocornia accessions was analysed: ETS sequence data showed a clear distinction between the two genera and between different Salicornia taxa. However, in some cases the ETS was not sufficiently variable to resolve morphologically distinct species. For the determination of optimal cultivation conditions, experiments on germination, seedling establishment and growth to a harvestable size were performed using different accessions of Salicornia spp. Experiments revealed that the percentage germination was greatest at lower salinities and with temperatures of 20/10 °C (day/night). Salicornia spp. produced more harvestable biomass in hydroponic culture than in sand culture, but the nutrient concentration requires optimization as hydroponically grown plants showed symptoms of stress. Salicornia ramosissima produced more harvestable biomass than Salicornia dolichostachya in artificial sea water containing 257 mM NaCl. Based on preliminary tests on ease of cultivation, gain in biomass, morphology and taste, S. dolichostachya was investigated in more detail, and the optimal salinity for seedling establishment was found to be 100 mM. Harvesting of S

  14. Exchange of atmospheric formic and acetic acids with trees and crop plants under controlled chamber and purified air conditions

    Science.gov (United States)

    Kesselmeier, J.; Bode, K.; Gerlach, C.; Jork, E.-M.

    We investigated the exchange of formic and acetic acids between the atmosphere and various tree species such as beech ( Fagus sylvatica L.), ash ( Fraxinus excelsior L.), spruce ( Picea abies L.) Karst, holm oak ( Quercus ilex L.), and birch ( Betula pendula L.). and some crop-plant species such as corn ( Zea mays, var. Banjo), pea ( Pisum sativum, var. Solara), barley ( Hordeum vulgare, var. Igri) and oat (Avena sativa, var. Wiesel). All experiments were done with dynamic enclosures flushed with purified oxidant-free air, containing only low or controlled amounts of the two acids. Significant and light-triggered emission of both acids from all tree species was observed. For one tree species (ash) a seasonal large increase in fall due to early leaf decomposition was found. The standard emission factors (30°C and PAR=1000 μmol m 2 s -1) given as (nmol m -2 min -1) for acetic and formic acids, respectively, were 8.1 and 29.7 (ash, autumn), 1.0 and 3.3 (ash, summer), 0.9 and 1.4 (beech), 0.7 and 1.45 (spruce), 1.9 and 2.4 (Holm oak) and 1.7 and 6.7 (birch). Rough estimation of global annual emissions range between 20 and 130 Gmol formic acid and 10 and 33 Gmol acetic acid. These numbers reflect a 15-30% contribution by forest emissions to the continental organic acid budget. As compared to the global total NMHC emissions low molecular weight organic acids are of minor importance. In contrast to the trees, none of the crop-plant species investigated showed an emission, but always a clear deposition of both acids. Both emission from trees as well as uptake by the agricultural plants could be related to transpiration rates and leaf conductances.

  15. CROPS AND CHEMISM OF PLANTS OF A MULTIVARIANT MODEL EXPERIMENT ON COAL COMBUSTION WASTE DEPOSITS. PART II (2012 – 2013

    Directory of Open Access Journals (Sweden)

    Jan Siuta

    2015-03-01

    Full Text Available Reclamation efficiency of composts produced from the mixture of municipal waste (Radiowo and ZUSOK, urban green waste composts (Complex, housing estate lawn mowing waste (plants and sewage sludge, as well as mineral fertilizer (NPK – without the use of any organic fertilizer, was assessed in a model experiment on an ash soil. The experiment was launched in 2005 and continued until the end of 2013. Crops were collected and subjected to the analysis in 2005, 2006 and between 2011 and 2012. In the period between 2007 and 2010 no agrotechnical treatments were carried out, with the experiment being limited to mere observation of the natural (spontaneous succession of plants. Reclamation doses of composts and sewage sludge were measured quantitatively, therefore they differed in the content of dry matter as well as in the contents of organic substances and minerals in the dry matter. The largest aggregated dry matter yield of plants (2005–2013 was reported in the Complex variant, and similarly, in the Radiowo and plant variants, whereas the ZUSOK variant reported the lowest aggregated dry matter field of plants. The yield-forming efficiency of NPK fertilizer was lower than in the case of compost and sludge variants. However, the field-forming efficiency of sewage sludge was lower than its fertilization potential as it was unstable and difficult to mix with the experimental soil. The results showed the yield-forming potential of plants on the experimental coal combustion waste deposits fertilized with composts and sewage sludge as well as the examples of the sites where sewage sludge could be used for the biological reclamation of landfills and spoil tips.

  16. The influence of pre-crop plants on the occurrence of arbuscular mycorrhizal fungi (Glomales and Phialophora graminicola associated with roots of winter XTriticosecale

    Directory of Open Access Journals (Sweden)

    Janusz Błaszkowski

    2014-08-01

    Full Text Available The influence of four pre-crop plant species on the occurrence of arbuscular mycorrhizal fungal (AMF, Glomales, Zygomycetes spores, mycorrhizae and Phialophora graminicola (Deacon Walker associated with roots of field-culuvated XTriticosecale Wittmack cv. Malno was investigated. The pre-crop plant species were Hordeum vutgare L., Lupinus luteus L., Pisum sativum L., and Vicia faba v. major Harz. Most spores and species of AMF were found when XTriticosecale was cultivated following P. sativum. Prior cropping with L. luteus caused the occurrence of the lowest number of spores among XTriticosecale roots. Mycorrhizal colonization of XTriticosecale was highest when planted after P. sativum and lowest when grown after L. luteus.

  17. Changes in plant-parasitic nematode populations in pineapple fields following inter-cycle cover crops.

    Science.gov (United States)

    Ko, M P; Schmitt, D P

    1996-12-01

    The use of plant-covers oat (Arena sativa L.), rhodesgrass (Chloris gayana Kunth), soybean (Glycine max [L.] Merr.), and marigold (Tagetes patula L.) during pineapple inter-cycle planting periods was investigated at two sites (Kunia and Whitmore, Oahu, HI) as a potential means to reduce population densities of Rotylenchulus reniformis, Helicotylenchus dihystera, and Paratylenchus spp. Clean fallow and fallow covered with pineapple-plant residues (mulch) were the controls without plant-cover. Regardless of treatments, population densities of R. reniformis declined with time at both sites to low residue levels by the end of the 6-month period. Treatment means of R. reniformis population densities in the plant-cover treatments were lower than the controls' (P = 0.05). The plant-cover treatments also effected higher rates of R. reniformis population decline at both sites during the period, being 2.0 to 2.2 times that of the mulch control and 1.2 to 1.4 times that of the fallow control. Plant-covers' effect on H. dihystera during the same period at both sites was variable, resulting in decreased, unchanged, or increased population densities. The change was especially obvious in the oat-cover treatment, where H. dihystera population densities increased 9 to 15-fold at both sites. Population of Paratylenchus spp. was absent or present at low levels at the sites throughout the period. Biological activities antagonistic to R. reniformis at Kunia were estimated at the end of 6 months by comparing the extent of nematode's reproduction (on cowpea seedlings) in the treatment soils that had been subjected to autoclaving or freezing temperature. Although higher indices of antagonistic activities were observed in soils with prior plant-cover treatments than in soils from the controls, none of the treatments resulted in conferring soils the increased ability to suppress re-introduced R. reniformis populations or enhance subsequent pineapple-plant growth.

  18. Plant evolution: pulses of extinction and speciation in gymnosperm diversity.

    Science.gov (United States)

    Davis, Charles C; Schaefer, Hanno

    2011-12-20

    Living gymnosperms represent the survivors of ancient seed plant lineages whose fossil record reaches back 270 million years. Two recent studies find that recent pulses of extinction and speciation have shaped today's gymnosperm diversity, contradicting the widespread assumption that gymnosperms have remained largely unchanged for tens of millions of years. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Evolution of operational parameters in a UASB wastewater plant

    African Journals Online (AJOL)

    DRINIE

    Keywords: wastewater, anaerobic treatment, UASB reactor, percentage elimination of pollutants. Introduction. Of the techniques used for the ... pollutant removal by the anaerobic digestion process used in the plant for different experimental conditions. ... Two sand-bed sludge dryers. Sampling and control parameters.

  20. Evolution of operational parameters in a UASB wastewater plant

    African Journals Online (AJOL)

    DRINIE

    2 Dpto. de Ingeniería Química y del Medio Ambiente, Escuela Superior de Ingenieros, Alameda de Urquijo s/n, 48013, Bilbao, Spain. Abstract. The results reported here are based on data of the Nova Pampulha Wastewater Treatment Plant, in the metropolitan region of Belo. Horizonte (Minas Gerais, Brazil) containing an ...

  1. Plant cell walls throughout evolution: towards a molecular understanding of their design principles

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-02-16

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche,which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  2. Suitability of non-lethal marker and marker-free systems for development of transgenic crop plants: present status and future prospects.

    Science.gov (United States)

    Manimaran, P; Ramkumar, G; Sakthivel, K; Sundaram, R M; Madhav, M S; Balachandran, S M

    2011-01-01

    Genetically modified crops are one of the prudent options for enhancing the production and productivity of crop plants by safeguarding from the losses due to biotic and abiotic stresses. Agrobacterium-mediated and biolistic transformation methods are used to develop transgenic crop plants in which selectable marker genes (SMG) are generally deployed to identify 'true' transformants. The commonly used SMG obtained from prokaryotic sources when employed in transgenic plants pose risks due to their lethal nature during selection process. In the recent past, some non-lethal SMGs have been identified and used for selection of transformants with increased precision and high selection efficiency. Considering the concerns related to bio-safety of the environment, it is desirable to remove the SMG in order to maximize the commercial success through wide adoption and public acceptance of genetically modified (GM) food crops. In this review, we examine the availability, and the suitability of wide range of non-lethal selection markers and elimination of SMG methods to develop marker-free transgenics for achieving global food security. As the strategies for marker-free plants are still in proof-of-concept stage, adaptation of new genomics tools for identification of novel non-lethal marker systems and its application for developing marker-free transgenics would further strengthen the crop improvement program. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Characterising microbial protein test substances and establishing their equivalence with plant-produced proteins for use in risk assessments of transgenic crops.

    Science.gov (United States)

    Raybould, Alan; Kilby, Peter; Graser, Gerson

    2013-04-01

    Most commercial transgenic crops are genetically engineered to produce new proteins. Studies to assess the risks to human and animal health, and to the environment, from the use of these crops require grams of the transgenic proteins. It is often extremely difficult to produce sufficient purified transgenic protein from the crop. Nevertheless, ample protein of acceptable purity may be produced by over-expressing the protein in microbes such as Escherichia coli. When using microbial proteins in a study for risk assessment, it is essential that their suitability as surrogates for the plant-produced transgenic proteins is established; that is, the proteins are equivalent for the purposes of the study. Equivalence does not imply that the plant and microbial proteins are identical, but that the microbial protein is sufficiently similar biochemically and functionally to the plant protein such that studies using the microbial protein provide reliable information for risk assessment of the transgenic crop. Equivalence is a judgement based on a weight of evidence from comparisons of relevant properties of the microbial and plant proteins, including activity, molecular weight, amino acid sequence, glycosylation and immuno-reactivity. We describe a typical set of methods used to compare proteins in regulatory risk assessments for transgenic crops, and discuss how risk assessors may use comparisons of proteins to judge equivalence.

  4. Principle and application of plant mutagenesis in crop improvement: a review

    OpenAIRE

    Yusuff Oladosu; Rafii, Mohd Y.; Norhani Abdullah; Ghazali Hussin; Asfaliza Ramli; Rahim, Harun A.; Gous Miah; Magaji Usman

    2016-01-01

    The first step in plant breeding is to identify suitable genotypes containing the desired genes among existing varieties, or to create one if it is not found in nature. In nature, variation occurs mainly as a result of mutations and without it, plant breeding would be impossible. In this context, the major aim in mutation-based breeding is to develop and improve well-adapted plant varieties by modifying one or two major traits to increase their productivity or quality. Both physical and chemi...

  5. Incidence and molecular diversity of poleroviruses infecting cucurbit crops and weed plants in Thailand.

    Science.gov (United States)

    Cheewachaiwit, S; Warin, N; Phuangrat, B; Rukpratanporn, S; Gajanandana, O; Balatero, C H; Chatchawankanphanich, O

    2017-07-01

    Overall, 244 samples of cucurbit crops with yellowing symptoms and selected weed species, from 15 provinces in Thailand, were screened by RT-PCR using primers Polero-CP-F and Polero-CP-R. A total of 160 samples (~66%) were infected by poleroviruses. Analysis of a 1.4 kb region covering the 3' RNA-dependent RNA polymerase (RdRp) gene, the intergenic non-coding region (iNCR), and the coat protein (CP), showed that four poleroviruses, namely, cucurbit aphid-borne yellows virus (CABYV), luffa aphid-borne yellows virus (LABYV), melon aphid-borne yellows virus (MABYV) and suakwa aphid-borne yellows virus (SABYV) were associated with the yellowing symptoms in cucurbit crops. Further analyses indicated presence of putative recombinant viruses referred to as CABYV-R and SABYV-R. CABYV-R was derived from the recombination between MABYV and the common strain of CABYV (CABYV-C). SABYV-R was derived from the recombination of MABYV and SABYV.

  6. A Review of the Applications of Chitin and Its Derivatives in Agriculture to Modify Plant-Microbial Interactions and Improve Crop Yields

    Directory of Open Access Journals (Sweden)

    Russell G. Sharp

    2013-11-01

    Full Text Available In recent decades, a greater knowledge of chitin chemistry, and the increased availability of chitin-containing waste materials from the seafood industry, have led to the testing and development of chitin-containing products for a wide variety of applications in the agriculture industry. A number of modes of action have been proposed for how chitin and its derivatives can improve crop yield. In addition to direct effects on plant nutrition and plant growth stimulation, chitin-derived products have also been shown to be toxic to plant pests and pathogens, induce plant defenses and stimulate the growth and activity of beneficial microbes. A repeating theme of the published studies is that chitin-based treatments augment and amplify the action of beneficial chitinolytic microbes. This article reviews the evidence for claims that chitin-based products can improve crop yields and the current understanding of the modes of action with a focus on plant-microbe interactions.

  7. Engineering Mycorrhizal Symbioses to Alter Plant Metabolism and Improve Crop Health

    OpenAIRE

    French, Katherine E.

    2017-01-01

    Creating sustainable bioeconomies for the 21st century relies on optimizing the use of biological resources to improve agricultural productivity and create new products. Arbuscular mycorrhizae (phylum Glomeromycota) form symbiotic relationships with over 80% of vascular plants. In return for carbon, these fungi improve plant health and tolerance to environmental stress. This symbiosis is over 400 million years old and there are currently over 200 known arbuscular mycorrhizae, with dozens of n...

  8. Next generation sequencing for studying viruses and RNA silencing-based antiviral defense in crop plants

    OpenAIRE

    Seguin, Jonathan

    2014-01-01

    The main objectives of this work have been to use next generation sequencing (NGS) and develop bioinformatics tools for plant virus diagnostics and genome reconstruction as well as for investigation of RNA silencing-based antiviral defense. In virus-infected plants, the host Dicer-like (DCL) enzymes process viral double-stranded RNAs into 21-24 nucleotide (nt) short interfering RNAs (siRNAs) which can potentially associate with Argonaute (AGO) proteins and guide the resulting RNA-induce silen...

  9. Effects of crop residue on soil and plant water evaporation in a dryland cotton system

    OpenAIRE

    Lascano, R.J.; R. L. Baumhardt

    1996-01-01

    Metadata only record This study is the context of dryland agriculture, which encompasses rainfed systems that require emphases on minimal fertilizer use and conservation of water and soil. Field trials compare cotton planted in terminated wheat stubble with conventional cotton (stubble incorporated with moldboard and disk). The objective is to differentiate between the contributions of soil and plant evaporation to total evapotranspiration on a daily and seasonal basis, using the numerical...

  10. Plant density affects light interception and yield in cotton grown as companion crop in young jujube plantations

    NARCIS (Netherlands)

    Zhang, D.; Zhang, L.; Liu, Jianguo; Han, S.; Wang, Q.; Evers, J.B.; Liu, Jun; Werf, van der W.; Li, L.

    2014-01-01

    Tree-crop mixturesmayincreaseyieldandrevenueespeciallyduringtheearlyyearsoftreeplantations. Jujube isgrownwidelyinChinafortheirfruits,andcottonisgainingpopularityasanunderstorycropin young jujubeplantations.Thereisaneedforinformationonproductivityandoptimalplantingdensities of

  11. Genome-Wide Comparative Analyses Reveal the Dynamic Evolution of Nucleotide-Binding Leucine-Rich Repeat Gene Family among Solanaceae Plants

    Science.gov (United States)

    Seo, Eunyoung; Kim, Seungill; Yeom, Seon-In; Choi, Doil

    2016-01-01

    Plants have evolved an elaborate innate immune system against invading pathogens. Within this system, intracellular nucleotide-binding leucine-rich repeat (NLR) immune receptors are known play critical roles in effector-triggered immunity (ETI) plant defense. We performed genome-wide identification and classification of NLR-coding sequences from the genomes of pepper, tomato, and potato using fixed criteria. We then compared genomic duplication and evolution features. We identified intact 267, 443, and 755 NLR-encoding genes in tomato, potato, and pepper genomes, respectively. Phylogenetic analysis and classification of Solanaceae NLRs revealed that the majority of NLR super family members fell into 14 subgroups, including a TIR-NLR (TNL) subgroup and 13 non-TNL subgroups. Specific subgroups have expanded in each genome, with the expansion in pepper showing subgroup-specific physical clusters. Comparative analysis of duplications showed distinct duplication patterns within pepper and among Solanaceae plants suggesting subgroup- or species-specific gene duplication events after speciation, resulting in divergent evolution. Taken together, genome-wide analysis of NLR family members provide insights into their evolutionary history in Solanaceae. These findings also provide important foundational knowledge for understanding NLR evolution and will empower broader characterization of disease resistance genes to be used for crop breeding. PMID:27559340

  12. Genome-wide Comparative Analyses Reveal the Dynamic Evolution of Nucleotide-Binding Leucine-Rich Repeat Gene Family among Solanaceae Plants

    Directory of Open Access Journals (Sweden)

    Eunyoung Seo

    2016-08-01

    Full Text Available Plants have evolved an elaborate innate immune system against invading pathogens. Within this system, intracellular nucleotide-binding leucine-rich repeat (NLR immune receptors are known play critical roles in effector-triggered immunity (ETI plant defense. We performed genome-wide identification and classification of NLR-coding sequences from the genomes of pepper, tomato, and potato using fixed criteria. We then compared genomic duplication and evolution features. We identified intact 267, 443, and 755 NLR-encoding genes in tomato, potato, and pepper genomes, respectively. Phylogenetic analyses and classification of Solanaceae NLRs revealed that the majority of NLR super family members fell into 14 subgroups, including a TIR-NLR (TNL subgroup and 13 non-TNL subgroups. Specific subgroups have expanded in each genome, with the expansion in pepper showing subgroup-specific physical clusters. Comparative analysis of duplications showed distinct duplication patterns within pepper and among Solanaceae plants suggesting subgroup- or species-specific gene duplication events after speciation, resulting in divergent evolution. Taken together, genome-wide analyses of NLR family members provide insights into their evolutionary history in Solanaceae. These findings also provide important foundational knowledge for understanding NLR evolution and will empower broader characterization of disease resistance genes to be used for crop breeding.

  13. Genome-wide analysis suggests divergent evolution of lipid phosphotases/phosphotransferase genes in plants.

    Science.gov (United States)

    Wang, Peng; Chen, Zhenxi; Kasimu, Rena; Chen, Yinhua; Zhang, Xiaoxiao; Gai, Jiangtao

    2016-08-01

    Genes of the LPPT (lipid phosphatase/phosphotransferase) family play important roles in lipid phosphorous transfer and triacylglycerol accumulation in plants. To provide overviews of the plant LPPT family and their overall relationships, here we carried out genome-wide identifications and analyses of plant LPPT family members. A total of 643 putative LPPT genes were identified from 48 sequenced plant genomes, among which 205 genes from 14 plants were chosen for further analyses. Plant LPPT genes belonged to three distinctive groups, namely the LPT (lipid phosphotransfease), LPP (lipid phosphatase), and pLPP (plastidic lipid phosphotransfease) groups. Genes of the LPT group could be further partitioned into three groups, two of which were only identified in terrestrial plants. Genes in the LPP and pLPP groups experienced duplications in early stages of plant evolution. Among 17 Zea mays LPPT genes, divergence of temporal-spatial expression patterns was revealed based on microarray data analysis. Peptide sequences of plant LPPT genes harbored different conserved motifs. A test of Branch Model versus One-ratio Model did not support significant selective pressures acting on different groups of LPPT genes, although quite different nonsynonymous evolutionary rates and selective pressures were observed. The complete picture of the plant LPPT family provided here should facilitate further investigations of plant LPPT genes and offer a better understanding of lipid biosynthesis in plants.

  14. MINERAL PROFILE EVOLUTION OF SOME MEDICINAL PLANTS WITH ANTIBACTERIAL EFFECTS

    Directory of Open Access Journals (Sweden)

    Claudia Pasca

    2016-11-01

    Full Text Available Individual minerals and antibacterial activity were investigated in 5 medicinal plants (pot marigold - Calendula officinalis, burdock - Arctium lappa, celandine - Chelidonium majus, basil- Ocimum basilicum, thyme - Thymus vulgaris using Atomic Absorption Spectroscopy (AAS technique and antibiogram  method. The antibacterial susceptibility has been evaluated over 12 strains isolated from milk microflora, belonging to Staphylococcus, Vibrio, Serratia and Bacillus genera. The obtained results show the best antibacterial effect with  Arctium lappa ethanol extracts, having inhibition areas of 6.3 to 17.5 mm, with an average of 9.0 mm and the highest determined mineral being Calcium. The results obtained open the prospect of using these medicinal plants as an alternative to be used for the control and cure of some mineral deficiencies or for preventing various diseases of the animals.

  15. S.I.I.A for monitoring crop evolution and anomaly detection in Andalusia by remote sensing

    Science.gov (United States)

    Rodriguez Perez, Antonio Jose; Louakfaoui, El Mostafa; Munoz Rastrero, Antonio; Rubio Perez, Luis Alberto; de Pablos Epalza, Carmen

    2004-02-01

    A new remote sensing application was developed and incorporated to the Agrarian Integrated Information System (S.I.I.A), project which is involved on integrating the regional farming databases from a geographical point of view, adding new values and uses to the original information. The project is supported by the Studies and Statistical Service, Regional Government Ministry of Agriculture and Fisheries (CAP). The process integrates NDVI values from daily NOAA-AVHRR and monthly IRS-WIFS images, and crop classes location maps. Agrarian local information and meteorological information is being included in the working process to produce a synergistic effect. An updated crop-growing evaluation state is obtained by 10-days periods, crop class, sensor type (including data fusion) and administrative geographical borders. Last ten years crop database (1992-2002) has been organized according to these variables. Crop class database can be accessed by an application which helps users on the crop statistical analysis. Multi-temporal and multi-geographical comparative analysis can be done by the user, not only for a year but also for a historical point of view. Moreover, real time crop anomalies can be detected and analyzed. Most of the output products will be available on Internet in the near future by a on-line application.

  16. Effects of domestic wastewater treated by anaerobic stabilization on soil pollution, plant nutrition, and cotton crop yield.

    Science.gov (United States)

    Uzen, Nese; Cetin, Oner; Unlu, Mustafa

    2016-12-01

    This study has aimed to determine the effects of treated wastewater on cotton yield and soil pollution in Southeastern Anatolia Region of Turkey during 2011 and 2012. The treated wastewater was provided from the reservoir operated as anaerobic stabilization. After treatment, suspended solids (28-60 mg/l), biological oxygen demand (29-30 mg/l), and chemical oxygen demand (71-112 mg/l) decreased significantly compared to those in the wastewater. There was no heavy metal pollution in the water used. There were no significant amounts of coliform bacteria, fecal coliform, and Escherichia coli compared to untreated wastewater. The cottonseed yield (31.8 g/plant) in the tanks where no commercial fertilizers were applied was considerably higher compared to the yield (17.2 g/plant) in the fertilized tanks where a common nitrogenous fertilizer was utilized. There were no significant differences between the values of soil pH. Soil electrical conductivity (EC) after the experiment increased from 0.8-1.0 to 0.9-1.8 dS/m. Heavy metal pollution did not occur in the soil and plants, because there were no heavy metals in the treated wastewater. It can be concluded that treated domestic wastewater could be used to grow in a controlled manner crops, such as cotton, that would not be used directly as human nutrients.

  17. High throughput selection of novel plant growth regulators: Assessing the translatability of small bioactive molecules from Arabidopsis to crops.

    Science.gov (United States)

    Rodriguez-Furlán, Cecilia; Miranda, Giovanna; Reggiardo, Martín; Hicks, Glenn R; Norambuena, Lorena

    2016-04-01

    Plant growth regulators (PGRs) have become an integral part of agricultural and horticultural practices. Accordingly, there is an increased demand for new and cost-effective products. Nevertheless, the market is limited by insufficient innovation. In this context chemical genomics has gained increasing attention as a powerful approach addressing specific traits. Here is described the successful implementation of a highly specific, sensitive and efficient high throughput screening approach using Arabidopsis as a model. Using a combination of techniques, 10,000 diverse compounds were screened and evaluated for several important plant growth traits including root and leaf growth. The phenotype-based selection allowed the compilation of a collection of putative Arabidopsis growth regulators with a broad range of activities and specificities. A subset was selected for evaluating their bioactivity in agronomically valuable plants. Their validation as growth regulators in commercial species such as tomato, lettuce, carrot, maize and turfgrasses reinforced the success of the screening in Arabidopsis and indicated that small molecules activity can be efficiently translated to commercial species. Therefore, the chemical genomics approach in Arabidopsis is a promising field that can be incorporated in PGR discovery programs and has a great potential to develop new products that can be efficiently used in crops. Copyright © 2016. Published by Elsevier Ireland Ltd.

  18. Production of Biomass Crops Using Biowastes on Low-Fertility Soil: 1. Influence of Biowastes on Plant and Soil Quality.

    Science.gov (United States)

    Esperschuetz, J; Anderson, C; Bulman, S; Lense, O; Horswell, J; Dickinson, N; Hofmann, R; Robinson, B H

    2016-11-01

    Land application of biosolids to low-fertility soil can improve soil quality by increasing concentrations of macronutrients and trace elements. Mixing biosolids with sawdust could reduce the risks of contaminant accumulation posed by rebuilding soils using biosolids alone. We aimed to determine the effects of biosolids and biosolids-sawdust on the plant quality and chemical composition of sorghum, rapeseed, and ryegrass. Plants were grown in a greenhouse over a 5-mo period in a low-fertility soil amended with biosolids (1250 kg N ha), biosolids-sawdust (0.5:1), or urea (200 kg N ha). Biosolids application increased the biomass of sorghum, rapeseed, and ryegrass up to 14.0, 11.9, and 4.1 t ha eq, respectively. Mixing sawdust with biosolids resulted in a growth response similar to biosolids treatments in rapeseed but nullified the effect of biosolids in sorghum. Urea fertilization provided insufficient nutrients to promote rapeseed growth and seed production, whereas seed yields after biosolids application were 2.5 t ha. Biosolids and biosolids-sawdust application enhanced plant quality by increasing element concentrations, especially Zn, and potentially toxic elements (Cd, Cr, Ni) did not exceed food safety standards. An application of 50 t ha of biosolids, equivalent to 1250 kg N ha, did not exceed current soil limits of Cu, Zn, and Cd and hence was effective in rebuilding soil without accumulating contaminants. The effect of mixing sawdust with biosolids varies with plant species but can further enhance plant nutrient quality in biomass and seeds, especially P, Cu, Zn, Mn, Fe, S, and Na. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  19. Contrasting Rates of Molecular Evolution and Patterns of Selection among Gymnosperms and Flowering Plants.

    Science.gov (United States)

    De La Torre, Amanda R; Li, Zhen; Van de Peer, Yves; Ingvarsson, Pär K

    2017-06-01

    The majority of variation in rates of molecular evolution among seed plants remains both unexplored and unexplained. Although some attention has been given to flowering plants, reports of molecular evolutionary rates for their sister plant clade (gymnosperms) are scarce, and to our knowledge differences in molecular evolution among seed plant clades have never been tested in a phylogenetic framework. Angiosperms and gymnosperms differ in a number of features, of which contrasting reproductive biology, life spans, and population sizes are the most prominent. The highly conserved morphology of gymnosperms evidenced by similarity of extant species to fossil records and the high levels of macrosynteny at the genomic level have led scientists to believe that gymnosperms are slow-evolving plants, although some studies have offered contradictory results. Here, we used 31,968 nucleotide sites obtained from orthologous genes across a wide taxonomic sampling that includes representatives of most conifers, cycads, ginkgo, and many angiosperms with a sequenced genome. Our results suggest that angiosperms and gymnosperms differ considerably in their rates of molecular evolution per unit time, with gymnosperm rates being, on average, seven times lower than angiosperm species. Longer generation times and larger genome sizes are some of the factors explaining the slow rates of molecular evolution found in gymnosperms. In contrast to their slow rates of molecular evolution, gymnosperms possess higher substitution rate ratios than angiosperm taxa. Finally, our study suggests stronger and more efficient purifying and diversifying selection in gymnosperm than in angiosperm species, probably in relation to larger effective population sizes. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  20. Unmanaged sexual reproduction and the dynamics of genetic diversity of a vegetatively propagated crop plant, cassava (Manihot esculenta Crantz), in a traditional farming system.

    Science.gov (United States)

    Elias, M; Penet, L; Vindry, P; McKey, D; Panaud, O; Robert, T

    2001-08-01

    Occurrence of intervarietal or interspecific natural crosses has been reported for many crop plants in traditional farming systems, underlining the potential importance of this source of genetic exchange for the dynamics of genetic diversity of crop plants. In this study, we use microsatellite loci to investigate the role of volunteer seedlings (plants originating from unmanaged sexual reproduction) in the dynamics of genetic diversity of cassava (Manihot esculenta Crantz), a vegetatively propagated crop, in a traditional farming system in Guyana. A previous field study showed that farmers incorporate such plants into the germplasm for vegetative propagation, and that many of them are likely to be assigned by farmers to recognized varieties. Under strict vegetative propagation clonality of varieties is expected. The high proportion of polyclonal varieties observed suggests that incorporation of seedlings into the germplasm for propagation is a frequent event. The molecular variability assessed with microsatellite markers shows that there is high differentiation among heterozygous varieties, whereas populations of seedlings do not depart from the proportions expected under Hardy-Weinberg assumptions. Assignment of seedlings to a recognized variety on the basis of morphological similarity greatly increases genetic diversity within the variety. We argue that recombination and gene flow play a major role in the dynamics of genetic diversity of cassava in traditional farming systems. Documenting unmanaged sexual reproduction and its genetic consequences is a prerequisite for defining strategies of in situ conservation of crop plant genetic resources.

  1. The method for detecting biological parameter of rice growth and early planting of paddy crop by using multi temporal remote sensing data

    Science.gov (United States)

    Domiri, D. D.

    2017-01-01

    Rice crop is the most important food crop for the Asian population, especially in Indonesia. During the growth of rice plants have four main phases, namely the early planting or inundation phase, the vegetative phase, the generative phase, and bare land phase. Monitoring the condition of the rice plant needs to be conducted in order to know whether the rice plants have problems or not in its growth. Application of remote sensing technology, which uses satellite data such as Landsat 8 and others which has a spatial and temporal resolution is high enough for monitoring the condition of crops such as paddy crop in a large area. In this study has been made an algorithm for monitoring rapidly of rice growth condition using Maximum of Vegetation Index (EVI Max). The results showed that the time of early planting can be estimated if known when EVI Max occurred. The value of EVI Max and when it occured can be known by trough spatial analysis of multitemporal EVI Landsat 8 or other medium spatial resolution satellites.

  2. Insights into Land Plant Evolution Garnered from the Marchantia polymorpha Genome.

    Science.gov (United States)

    Bowman, John L; Kohchi, Takayuki; Yamato, Katsuyuki T; Jenkins, Jerry; Shu, Shengqiang; Ishizaki, Kimitsune; Yamaoka, Shohei; Nishihama, Ryuichi; Nakamura, Yasukazu; Berger, Frédéric; Adam, Catherine; Aki, Shiori Sugamata; Althoff, Felix; Araki, Takashi; Arteaga-Vazquez, Mario A; Balasubrmanian, Sureshkumar; Barry, Kerrie; Bauer, Diane; Boehm, Christian R; Briginshaw, Liam; Caballero-Perez, Juan; Catarino, Bruno; Chen, Feng; Chiyoda, Shota; Chovatia, Mansi; Davies, Kevin M; Delmans, Mihails; Demura, Taku; Dierschke, Tom; Dolan, Liam; Dorantes-Acosta, Ana E; Eklund, D Magnus; Florent, Stevie N; Flores-Sandoval, Eduardo; Fujiyama, Asao; Fukuzawa, Hideya; Galik, Bence; Grimanelli, Daniel; Grimwood, Jane; Grossniklaus, Ueli; Hamada, Takahiro; Haseloff, Jim; Hetherington, Alexander J; Higo, Asuka; Hirakawa, Yuki; Hundley, Hope N; Ikeda, Yoko; Inoue, Keisuke; Inoue, Shin-Ichiro; Ishida, Sakiko; Jia, Qidong; Kakita, Mitsuru; Kanazawa, Takehiko; Kawai, Yosuke; Kawashima, Tomokazu; Kennedy, Megan; Kinose, Keita; Kinoshita, Toshinori; Kohara, Yuji; Koide, Eri; Komatsu, Kenji; Kopischke, Sarah; Kubo, Minoru; Kyozuka, Junko; Lagercrantz, Ulf; Lin, Shih-Shun; Lindquist, Erika; Lipzen, Anna M; Lu, Chia-Wei; De Luna, Efraín; Martienssen, Robert A; Minamino, Naoki; Mizutani, Masaharu; Mizutani, Miya; Mochizuki, Nobuyoshi; Monte, Isabel; Mosher, Rebecca; Nagasaki, Hideki; Nakagami, Hirofumi; Naramoto, Satoshi; Nishitani, Kazuhiko; Ohtani, Misato; Okamoto, Takashi; Okumura, Masaki; Phillips, Jeremy; Pollak, Bernardo; Reinders, Anke; Rövekamp, Moritz; Sano, Ryosuke; Sawa, Shinichiro; Schmid, Marc W; Shirakawa, Makoto; Solano, Roberto; Spunde, Alexander; Suetsugu, Noriyuki; Sugano, Sumio; Sugiyama, Akifumi; Sun, Rui; Suzuki, Yutaka; Takenaka, Mizuki; Takezawa, Daisuke; Tomogane, Hirokazu; Tsuzuki, Masayuki; Ueda, Takashi; Umeda, Masaaki; Ward, John M; Watanabe, Yuichiro; Yazaki, Kazufumi; Yokoyama, Ryusuke; Yoshitake, Yoshihiro; Yotsui, Izumi; Zachgo, Sabine; Schmutz, Jeremy

    2017-10-05

    The evolution of land flora transformed the terrestrial environment. Land plants evolved from an ancestral charophycean alga from which they inherited developmental, biochemical, and cell biological attributes. Additional biochemical and physiological adaptations to land, and a life cycle with an alternation between multicellular haploid and diploid generations that facilitated efficient dispersal of desiccation tolerant spores, evolved in the ancestral land plant. We analyzed the genome of the liverwort Marchantia polymorpha, a member of a basal land plant lineage. Relative to charophycean algae, land plant genomes are characterized by genes encoding novel biochemical pathways, new phytohormone signaling pathways (notably auxin), expanded repertoires of signaling pathways, and increased diversity in some transcription factor families. Compared with other sequenced land plants, M. polymorpha exhibits low genetic redundancy in most regulatory pathways, with this portion of its genome resembling that predicted for the ancestral land plant. PAPERCLIP. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  3. Biocide plants as a sustainable tool for the control of pests and pathogens in vegetable cropping systems

    Directory of Open Access Journals (Sweden)

    Trifone D'Addabbo

    2014-11-01

    Full Text Available Synthetic pesticides have played a major role in crop protection related to the intensification of agricultural systems. In the recent years, environmental side effects and health concerns raised by an indiscriminate use have led the EU to the ban of many synthetic pesticides. As a result of this drastic revision, currently there is a strong need for new and alternative pest control methods. An interesting source of biorational pesticides may be represented by the biocidal compounds naturally occurring in plants as products of the secondary metabolism. Groups of plant secondary metabolites most promising for the development of pesticidal formulations are glucosinolates, saponins, and more generally terpenoid phytoconstituents, such as essential oil and their constituents. Glucosinolates are thioglucosidic secondary metabolites occurring mainly in the Brassicaceae and, at a less extent, in Capparidaceae families. The incorporation of glucosinolate- containing plant material into the soil results in degradation products highly toxic to soilborne pest, pathogens and weeds. This practice, known as biofumigation, may be considered as an ecological alternative to soil toxic fumigants. Plant-derived saponins are triterpene glycosides present in top and root tissues of plant species of the families Leguminosae, Alliaceae, Asteraceae, Polygalaceae and Agavaceae. Saponins and saponin-rich plant materials have been also reported for a biocidal activity on phytoparasites and soilborne plant pathogens. Essential oils are volatile, natural, heterogeneous mixtures of single substances, mainly terpenes and phenolics, formed as secondary metabolites by aromatic plants belonging to several botanical families. Among terpenes, limonoid triterpenes have been demonstrated to possess interesting insecticidal, nematicidal and antifungal properties. Occurrence of these compounds is mainly limited to Meliaceae and Rutaceae. Alkaloids, phenolics, cyanogenic glucosides

  4. Modelling exposure of workers, residents and bystanders to vapour of plant protection products after application to crops.

    Science.gov (United States)

    van den Berg, F; Jacobs, C M J; Butler Ellis, M C; Spanoghe, P; Doan Ngoc, K; Fragkoulis, G

    2016-12-15

    Agricultural use of plant protection products can result in exposure of bystanders, residents, operators and workers. Within the European Union (EU) FP7 project BROWSE, a tool based on a set of models and scenarios has been developed, aiming to assess the risk of exposure of humans to these products. In the present version of the tool only a first conservative tier is available for outdoor vapour exposure assessment. In the vapour exposure evaluation, the target concentrations in air at 10m distance from the edge of a treated field are calculated for specific scenarios for each EU regulatory zone. These scenarios have been selected to represent reasonable worst case volatilisation conditions. The exposure assessment is based on a series of weekly applications in a five year period to cover a wide range of meteorological conditions. The volatilisation from the crop is calculated using the PEARL model and this PEARL output provides the emission strength used as input for the short term version of the atmospheric transport model OPS. The combined PEARL-OPS model is tested against measurements from a field experiment. First results of this test show that the mean concentration level was predicted fairly well. However, sometimes the differences between observations and simulations were found to be substantial. Improvements are suggested for the vapour exposure scenarios as well as for further model development. In the current version of the BROWSE tool a simplified procedure is used to assess single and multiple applications. The actual period of application and the time of application during the day are fixed, and the growth stage of the crop cannot be taken into account. Moreover, competing processes such as penetration of the substance into the plant tissue are not considered. The effect of these factors on the target exposure concentrations is discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Parasitic plants have increased rates of molecular evolution across all three genomes.

    Science.gov (United States)

    Bromham, Lindell; Cowman, Peter F; Lanfear, Robert

    2013-06-19

    Theoretical models and experimental evidence suggest that rates of molecular evolution could be raised in parasitic organisms compared to non-parasitic taxa. Parasitic plants provide an ideal test for these predictions, as there are at least a dozen independent origins of the parasitic lifestyle in angiosperms. Studies of a number of parasitic plant lineages have suggested faster rates of molecular evolution, but the results of some studies have been mixed. Comparative analysis of all parasitic plant lineages, including sequences from all three genomes, is needed to examine the generality of the relationship between rates of molecular evolution and parasitism in plants. We analysed DNA sequence data from the mitochondrial, nuclear and chloroplast genomes for 12 independent evolutionary origins of parasitism in angiosperms. We demonstrated that parasitic lineages have a faster rate of molecular evolution than their non-parasitic relatives in sequences for all three genomes, for both synonymous and nonsynonymous substitutions. Our results prove that raised rates of molecular evolution are a general feature of parasitic plants, not confined to a few taxa or specific genes. We discuss possible causes for this relationship, including increased positive selection associated with host-parasite arms races, relaxed selection, reduced population size or repeated bottlenecks, increased mutation rates, and indirect causal links with generation time and body size. We find no evidence that faster rates are due to smaller effective populations sizes or changes in selection pressure. Instead, our results suggest that parasitic plants have a higher mutation rate than their close non-parasitic relatives. This may be due to a direct connection, where some aspect of the parasitic lifestyle drives the evolution of raised mutation rates. Alternatively, this pattern may be driven by an indirect connection between rates and parasitism: for example, parasitic plants tend to be smaller than

  6. Evaluation of Crop-Livestock Integration Systems among Farm ...

    African Journals Online (AJOL)

    USER

    ... of crops and livestock. Keywords: Crop-livestock integration systems, adopted village, farm family. .... crop is planted at about the time when the first crop is being harvested. Crop residues ..... Agronomy Monograph, 54. Madison, WI.

  7. Evolution of the 3R-MYB Gene Family in Plants.

    Science.gov (United States)

    Feng, Guanqiao; Burleigh, J Gordon; Braun, Edward L; Mei, Wenbin; Barbazuk, W Brad

    2017-04-20

    Plant 3R-MYB transcription factors are an important subgroup of the MYB super family in plants; however, their evolutionary history and functions remain poorly understood. We identified 225 3R-MYB proteins from 65 plant species, including algae and all major lineages of land plants. Two segmental duplication events preceding the common ancestor of angiosperms have given rise to three subgroups of the 3R-MYB proteins. Five conserved introns in the domain region of the 3R-MYB genes were identified, which arose through a step-wise pattern of intron gain during plant evolution. Alternative splicing (AS) analysis of selected species revealed that transcripts from more than 60% of 3R-MYB genes undergo AS. AS could regulate transcriptional activity for some of the plant 3R-MYBs by generating different regulatory motifs. The 3R-MYB genes of all subgroups appear to be enriched for Mitosis-Specific Activator (MSA) element core sequences within their upstream promoter region, which suggests a functional involvement in cell cycle. Notably, expression of 3R-MYB genes from different species exhibits differential regulation under various abiotic stresses. These data suggest that the plant 3R-MYBs function in both cell cycle regulation and abiotic stress response, which may contribute to the adaptation of plants to a sessile lifestyle. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  8. Crop modeling: Studying the effect of water stress on the driving forces governing plant water potential

    Science.gov (United States)

    van Emmerik, T. H. M.; Mirfenderesgi, G.; Bohrer, G.; Steele-Dunne, S. C.; Van De Giesen, N.

    2015-12-01

    Water stress is one of the most important environmental factors that influence plant water dynamics. To prevent excessive water loss and physiological damage, plants can regulate transpiration by adjusting the stomatal aperture. This enhances survival, but also reduced photosynthesis and productivity. During periods of low water availability, stomatal regulation is a trade-off between optimization of either survival or production. Water stress defence mechanisms lead to significant changes in plant dynamics, e.g. leaf and stem water content. Recent research has shown that water content in a corn canopy can change up to 30% diurnally as a result of water stress, which has a considerable influence on radar backscatter from a corn canopy [1]. This highlighted the potential of water stress detection using radar. To fully explore the potential of water stress monitoring using radar, we need to understand the driving forces governing plant water potential. For this study, the recently developed the Finite-Element Tree-Crown Hydrodynamic model version 2 (FETCH2) model is applied to a corn canopy. FETCH2 is developed to resolve the hydrodynamic processes within a plant using the porous media analogy, allowing investigation of the influence of environmental stress factors on plant dynamics such as transpiration, photosynthesis, stomatal conductance, and leaf and stem water content. The model is parameterized and evaluated using a detailed dataset obtained during a three-month field experiment in Flevoland, the Netherlands, on a corn canopy. [1] van Emmerik, T., S. Steele-Dunne, J. Judge and N. van de Giesen: "Impact of Diurnal Variation in Vegetation Water Content on Radar Backscatter of Maize During Water Stress", Geosciences and Remote Sensing, IEEE Transactions on, vol. 52, issue 7, doi: 10.1109/TGRS.2014.2386142, 2015.

  9. Advanced technologies for plant cell wall evolution and diversity

    DEFF Research Database (Denmark)

    Fangel, Jonatan Ulrik

    Plant cell walls consist of polysaccharides, glycoproteins and phenolic polymers interlinked together in a highly complex network. The detailed analysis of cell walls is challenging because of their inherent complexity and heterogeneity. Also, complex carbohydrates, unlike proteins and nucleotides...... probes (monoclonal antibodies mAbs and carbohydrate binding modules, CBMs) to rapidly profile polysaccharides across a sample set. During my PhD I have further developed the CoMPP technique and used it for cell wall analysis within the context of a variety of applied and fundamental projects. The data...

  10. Influence of Plant Diversity on the Numerical Response of Eriopis connexa (Coleoptera: Coccinellidae to Changes in Cereal Aphid Density in Wheat Crops

    Directory of Open Access Journals (Sweden)

    María C. Tulli

    2013-01-01

    Full Text Available Cereal aphids cause economic injury to wheat crops. In Argentina, Eriopis connexa is an indigenous ladybird. In the present study, the numerical response of E. connexa to changes in aphid density on wheat crops with high and low plant diversity was investigated. The study was carried out in Balcarce, Buenos Aires, Argentina, from September to December 2007 and 2008, on two wheat crops with either a higher plant diversity (HPD with refuge strips or a lower plant diversity (LPD without refuge strips. Crops were sampled every week and the abundance of aphids and E. connexa was recorded. The dominant aphid species were Schizaphis graminum, Metopolophium dirhodum, and Sitobion avenae. Eriopis connexa showed a linear increase in the numerical response to an increase in aphid density, which varied in space and time. The abundance of E. connexa increased in relation to the crop development and aphid population and was higher in the HPD than in the LPD system. This predator increased its reproductive numerical response only in 2008, with a significant liner response in the HPD system. This suggests that the potential of E. connexa as a predator of cereal aphids also increases directly in proportion to landscape vegetal diversity.

  11. Airborne Thermal Imagery to Detect the Seasonal Evolution of Crop Water Status in Peach, Nectarine and Saturn Peach Orchards

    OpenAIRE

    Joaquim Bellvert; Jordi Marsal; Joan Girona; Victoria Gonzalez-Dugo; Elías Fereres; Ustin, Susan L; Zarco-Tejada, Pablo J.

    2016-01-01

    In the current scenario of worldwide limited water supplies, conserving water is a major concern in agricultural areas. Characterizing within-orchard spatial heterogeneity in water requirements would assist in improving irrigation water use efficiency and conserve water. The crop water stress index (CWSI) has been successfully used as a crop water status indicator in several fruit tree species. In this study, the CWSI was developed in three Prunus persica L. cultivars at different phenologica...

  12. Selenium (Se) improves drought tolerance in crop plants--a myth or fact?

    Science.gov (United States)

    Ahmad, Rashid; Waraich, Ejaz Ahmad; Nawaz, Fahim; Ashraf, Muhammad Y; Khalid, Muhammad

    2016-01-30

    Climate change has emerged as one of the most complex challenges of the 21st century and has become an area of interest in the past few decades. Many countries of the world have become extremely vulnerable to the impacts of climate change. The scarcity of water is a serious concern for food security of these countries and climate change has aggravated the risks of extreme events like drought. Oxidative stress, caused by a variety of active oxygen species formed under drought stress, damages many cellular constituents, such as carbohydrates, lipids, nucleic acids and proteins, which ultimately reduces plant growth, respiration and photosynthesis. Se has become an element of interest to many biologists owing to its physiological and toxicological importance. It plays a beneficial role in plants by enhancing growth, reducing damage caused by oxidative stress, enhancing chlorophyll content under light stress, stimulating senesce to produce antioxidants and improving plant tolerance to drought stress by regulating water status. Researchers have adopted different strategies to evaluate the role of selenium in plants under drought stress. Some of the relevant work available regarding the role of Se in alleviating adverse effect of drought stress is discussed in this paper. © 2015 Society of Chemical Industry.

  13. Evaluation of some Australian plant species for potential as hydrocarbon-producing crops

    Energy Technology Data Exchange (ETDEWEB)

    Williams, L.R.; Casali, J.; Home, V.

    1981-01-01

    Calotropis procera, Calotropis gigantea, Cryptostegia grandiflora, and Asclepias fruticosa were evaluated for their potential to be cultivated to provide a renewable source of fuel and energy. The cyclohexane extracts of the dried plants gave thick dark oils which were not mobile at less than 70-80 degrees. From elemental analysis, a proportion of O was always present in the extract.

  14. Grain and straw for whole plant: implications for crop management and genetic improvement strategies

    NARCIS (Netherlands)

    Schiere, J.B.; Joshi, A.L.; Seetharam, A.; Oosting, S.J.; Goodchild, A.V.; Deinum, B.; Keulen, van H.

    2004-01-01

    Straws and stovers are often called `by-products` of grain production even though they are increasingly important, e.g. for animal feed, thatching, soil improvement, mushroom production and industrial use. As a result, plant breeders, agronomists, economists and animal nutritionists have to pay more

  15. Selecting an ornamental pepper banker plant for Amblyseius swirskii in floriculture crops

    Science.gov (United States)

    Preference of phytoseiid mite Amblyseius swirskii (Athias-Henriot) was assessed on four cultivars of ornamental pepper banker plant candidates; Red Missile (RM), Masquerade (MA), Explosive Ember (EE), and Black Pearl (BP) for potential control of pestiferous insects in floriculture. Cultivar prefere...

  16. An indicator of plant species richness of semi-natural habitats and crops on arable farms

    NARCIS (Netherlands)

    Manhoudt, A.G.E.; Udo de Haes, H.A.; Snoo, de G.R.

    2005-01-01

    As a straightforward method of assessing on-farm biodiversity, plant species numbers were compared in a fixed sampling area for each type of habitat distinguished independent of farm size and applicable for comparing different farm strategies. Using the species-area relationship, the minimum

  17. Seed treatments with thiamine reduce the performance of generalist and specialist aphids on crop plants.

    Science.gov (United States)

    Hamada, A M; Fatehi, J; Jonsson, L M V

    2018-02-01

    Thiamine is a vitamin that has been shown to act as a trigger to activate plant defence and reduce pathogen and nematode infection as well as aphid settling and reproduction. We have here investigated whether thiamine treatments of seeds (i.e. seed dressing) would increase plant resistance against aphids and whether this would have different effects on a generalist than on specialist aphids. Seeds of wheat, barley, oat and pea were treated with thiamine alone or in combination with the biocontrol bacteria Pseudomonas chlororaphis MA 342 (MA 342). Plants were grown in climate chambers. The effects of seed treatment on fecundity, host acceptance and life span were studied on specialist aphids bird cherry-oat aphid (Rhopalosiphum padi L.) and pea aphid (Acyrthosiphon pisum Harris) and on the generalist green peach aphid (Myzus persicae, Sulzer). Thiamine seed treatments reduced reproduction and host acceptance of all three aphid species. The number of days to reproduction, the length of the reproductive life, the fecundity and the intrinsic rate of increase were found reduced for bird cherry-oat aphid after thiamine treatment of the cereal seeds. MA 342 did not have any effect in any of the plant-aphid combinations, except a weak decrease of pea aphid reproduction on pea. The results show that there are no differential effects of either thiamine or MA 342 seed treatments on specialist and generalist aphids and suggest that seed treatments with thiamine has a potential in aphid pest management.

  18. Elemental Characterization of Romanian Crop Medicinal Plants by Neutron Activation Analysis.

    Science.gov (United States)

    Haidu, Daniela; Párkányi, Dénes; Moldovan, Radu Ioan; Savii, Cecilia; Pinzaru, Iulia; Dehelean, Cristina; Kurunczi, Ludovic

    2017-01-01

    The metallic elements concentrations of medicinal plants (coriander, dill, Echinacea , lavender, chamomile, mint, and plantain, used for phytopharmaceutical products), cultivated in unpolluted region, were analyzed by neutron activation analysis. The essential nutrients, macro-, micro-, and trace elements (K, Ca, Mg, Na, Fe, Mn, Rb, Sr, and Zn), potentially toxic elements (Al, As, Ba, Co, Sb, Cr, and V), and rare earth elements were monitored and were compared with those presented in the literature. An estimation of their contributions to intake and toxicity for a person was made, which revealed that (a) teas prepared from the examined plants represent useful contribution to the food provided intake of three essential macronutrients (K, Ca, and Mg); (b) the Cu, Mn, Rb, Sr, Zn, and rare earths levels are normal or low; (c) the quantities of As, Ba, Co, Sb, Cr, and V do not represent toxicological concerns; (d) the examination of the estimated Al and Fe quantities recovered in infusions in the conditions of usual daily tea consumption is below the Tolerable Daily Intake values. The strategy of cultivation of medicinal plants in unpolluted areas is efficient and beneficial. However, individual plants ability to concentrate preferentially certain elements suggests controlling the contamination level of raw materials.

  19. Elemental Characterization of Romanian Crop Medicinal Plants by Neutron Activation Analysis

    Directory of Open Access Journals (Sweden)

    Daniela Haidu

    2017-01-01

    Full Text Available The metallic elements concentrations of medicinal plants (coriander, dill, Echinacea, lavender, chamomile, mint, and plantain, used for phytopharmaceutical products, cultivated in unpolluted region, were analyzed by neutron activation analysis. The essential nutrients, macro-, micro-, and trace elements (K, Ca, Mg, Na, Fe, Mn, Rb, Sr, and Zn, potentially toxic elements (Al, As, Ba, Co, Sb, Cr, and V, and rare earth elements were monitored and were compared with those presented in the literature. An estimation of their contributions to intake and toxicity for a person was made, which revealed that (a teas prepared from the examined plants represent useful contribution to the food provided intake of three essential macronutrients (K, Ca, and Mg; (b the Cu, Mn, Rb, Sr, Zn, and rare earths levels are normal or low; (c the quantities of As, Ba, Co, Sb, Cr, and V do not represent toxicological concerns; (d the examination of the estimated Al and Fe quantities recovered in infusions in the conditions of usual daily tea consumption is below the Tolerable Daily Intake values. The strategy of cultivation of medicinal plants in unpolluted areas is efficient and beneficial. However, individual plants ability to concentrate preferentially certain elements suggests controlling the contamination level of raw materials.

  20. Glutaredoxins in plant development, abiotic stress response, and iron homeostasis: From model organisms to crops

    Science.gov (United States)

    Plant growth, development, and response to environmental stress require the judicious balance of reactive oxygen species (ROS). Glutaredoxins (GRXs) are a group of oxidoreductases that participate in the control of ROS and are traditionally defined as redox regulators. New studies suggest the member...

  1. Twenty Years of Brassinosteroids : Steroidal Plant Hormones Warrant Better Crops for the XXI Century

    NARCIS (Netherlands)

    Khripach, V.; Zhabinskii, V.; Groot, de C.P.G.M.

    2000-01-01

    The discovery of brassinosteroids (BS) just over 20 years ago opened a new era in studies of bio-regulation in living organisms. Previously, the only known role of steroids as hormones was in animals and fungi; now a steroidal hormone in plants had been added. Progress in brassinosteroid research

  2. Observation and Modeling of the Evolution of Texas Power Plant Plumes

    Science.gov (United States)

    During the second Texas Air Quality Study 2006 (TexAQS II), a full range of pollutants was measured by aircraft in eastern Texas during successive transects of power plant plumes (PPPs). A regional photochemical model is applied to simulate the physical and chemical evolution of ...

  3. Microbial amelioration of crop salinity stress.

    Science.gov (United States)

    Dodd, Ian C; Pérez-Alfocea, Francisco

    2012-05-01

    The use of soil and irrigation water with a high content of soluble salts is a major limiting factor for crop productivity in the semi-arid areas of the world. While important physiological insights about the mechanisms of salt tolerance in plants have been gained, the transfer of such knowledge into crop improvement has been limited. The identification and exploitation of soil microorganisms (especially rhizosphere bacteria and mycorrhizal fungi) that interact with plants by alleviating stress opens new alternatives for a pyramiding strategy against salinity, as well as new approaches to discover new mechanisms involved in stress tolerance. Although these mechanisms are not always well understood, beneficial physiological effects include improved nutrient and water uptake, growth promotion, and alteration of plant hormonal status and metabolism. This review aims to evaluate the beneficial effects of soil biota on the plant response to saline stress, with special reference to phytohormonal signalling mechanisms that interact with key physiological processes to improve plant tolerance to the osmotic and toxic components of salinity. Improved plant nutrition is a quite general beneficial effect and may contribute to the maintenance of homeostasis of toxic ions under saline stress. Furthermore, alteration of crop hormonal status to decrease evolution of the growth-retarding and senescence-inducing hormone ethylene (or its precursor 1-aminocyclopropane-1-carboxylic acid), or to maintain source-sink relations, photosynthesis, and biomass production and allocation (by altering indole-3-acetic acid and cytokinin biosynthesis) seem to be promising target processes for soil biota-improved crop salt tolerance.

  4. Operational Optimization of Large-Scale Parallel-Unit SWRO Desalination Plant Using Differential Evolution Algorithm

    Science.gov (United States)

    Wang, Xiaolong; Jiang, Aipeng; Jiangzhou, Shu; Li, Ping

    2014-01-01

    A large-scale parallel-unit seawater reverse osmosis desalination plant contains many reverse osmosis (RO) units. If the operating conditions change, these RO units will not work at the optimal design points which are computed before the plant is built. The operational optimization problem (OOP) of the plant is to find out a scheduling of operation to minimize the total running cost when the change happens. In this paper, the OOP is modelled as a mixed-integer nonlinear programming problem. A two-stage differential evolution algorithm is proposed to solve this OOP. Experimental results show that the proposed method is satisfactory in solution quality. PMID:24701180

  5. Migration and Enrichment of Arsenic in the Rock-Soil-Crop Plant System in Areas Covered with Black Shale, Korea

    Directory of Open Access Journals (Sweden)

    Ji-Min Yi

    2003-01-01

    Full Text Available The Okchon black shale, which is part of the Guryongsan Formation or the Changri Formation of Cambro-Ordovician age in Korea provides a typical example of natural geological materials enriched with potentially toxic elements such as U, V, Mo, As, Se, Cd, and Zn. In this study, the Dukpyung and the Chubu areas were selected to investigate the migration and enrichment of As and other toxic elements in soils and crop plants in areas covered with black shale. Rock and soil samples digested in 4-acid solution (HCl+HNO3+HF+HClO4 were analyzed for As and other heavy metals by ICP-AES and ICP-MS, and plant samples by INAA. Mean concentration of As in Okchon black shale is higher than those of both world average values of shale and black shale. Especially high concentration of 23.2 mg As kg-1 is found in black shale from the Dukpyung area. Mean concentration of As is highly elevated in agricultural soils from the Dukpyung (28.2 mg kg-1 and the Chubu areas (32.6 mg kg-1. As is highly elevated in rice leaves from the Dukpyung (1.14 mg kg-1 and the Chubu areas (1.35 mg kg-1. The biological absorption coefficient (BAC of As in plant species decreases in the order of rice leaves > corn leaves > red pepper = soybean leaves = sesame leaves > corn stalks > corn grains. This indicates that leafy plants tend to accumulate As from soil to a greater degree than cereal products such as grains.

  6. A dynamic model for calculating methane emissions from digestate based on co-digestion of animal manure and biogas crops in full scale German biogas plants.

    Science.gov (United States)

    Muha, Ivo; Linke, Bernd; Wittum, Gabriel

    2015-02-01

    The focus of this work is the development of a model for the estimation of methane emissions for storage tanks of biogas plants. Those can be estimated depending on (i) hydraulic retention time in the digester, (ii) an arbitrary removal rate of the digestate from the storage tank and (iii) arbitrary temperature conditions in the storage tank. Furthermore, the model is capable of considering an arbitrary mixture of manure and crops in the input material. The model was validated by data from 21 full scale biogas plants in Germany digesting cow manure and crops. A realistic scenario for the removal rate and temperature conditions in the storage tank was then investigated and special emphasis was given to the effect of hydraulic retention time and proportion of crops in the mixture on the input VS methane yield from the digester and the storage tank. Copyright © 2014. Published by Elsevier Ltd.

  7. Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants

    DEFF Research Database (Denmark)

    Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora

    2015-01-01

    The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been ...... of young inflorescences in the monocot ryegrass, related to conditions for doubled haploid formation. Likewise, treatment of dicot spring oilseed rape with elevated CO2 concentration resulted in distinct patterns of enzyme activity responses in leaves....

  8. The role of local species abundance in the evolution of pollinator attraction in flowering plants.

    Science.gov (United States)

    Sargent, Risa D; Otto, Sarah P

    2006-01-01

    We present a population genetic model that incorporates aspects of pollinator efficiency and abundance to examine the effect of the local plant community on the evolution of floral trait specialization. Our model predicts that plant species evolve to be pollinator specialists on the most effective and common pollinators when their abundance is low relative to other plant species in the community (i.e., conspecific pollen is relatively rare) and evolve to be pollinator generalists when they are numerically dominant (i.e., conspecific pollen is abundant). Strong flower constancy also favors generalist floral traits. Furthermore, generalist species are predicted to differentiate when there is a concave trade-off in attracting pollinator species with different floral trait preferences. This result implies that populations that evolve toward a generalist strategy may be more prone to speciation. Ours is the first theoretical model to include local species abundance explicitly, despite the fact that it has been previously identified as an important factor in the evolution of plant specialization. Our results add a layer of ecological complexity to previous models of floral evolution and therefore have the potential to improve our power to predict circumstances under which specialized and generalized plant-pollinator interactions should evolve.

  9. A GIS TOOL TO EVALUATE THE SPATIAL EVOLUTION OF HYDRO-THERMIC FEATURES DURING GROWING SEASON OF VEGETABLE CROPS IN ELBE RIVER LOWLAND (POLABI

    Directory of Open Access Journals (Sweden)

    VERA POTOP

    2012-11-01

    Full Text Available A GIS tool to evaluate the spatial evolution of hydro-thermic features during growing season of vegetable crops in Elbe River lowland (Polabi. This article presents the results of the first study on combined mezoclimatological, microclimatological and topographical tools for evaluating precision farming in the growth of vegetable crops in the Elbe River lowland (Polabi region from the Czech Republic. We assess the variability of basically climatological characteristics in relation to topographic characteristics at the regional (Polabi and local (agricultural farm scales. At regional scale, interpolation approach is based on local linear regression and universal kriging interpolation. At local scale, two conventional interpolation methods, spline and local ordinary kriging with a Gaussian model variance across the fields, were applied. The local spline interpolators have been used in developing digital elevation models (DEMs and to determine the slope angle inclination of vegetable fields. The DEMs of the vegetable crops fields was developed at a 10 m x 10 m resolution based on elevation data collected in the field by a hand-held RTK- Global Positioning System receiver. This tool allowed the distinction of microclimatic conditions that produce altitude-slope-related patterns of the spatial-temporal distribution of the basic meteorological elements during growing season of vegetable crops. The effect of slope on diurnal extreme temperatures in the vegetable cropped field conditions was more pronounced than that of elevation. Accordingly to developed maps, the warmest and longest duration of sunshine, and the least precipitation totals during growing season occurred in the middle part of Polabi.

  10. Environmental stress-mediated changes in transcriptional and translational regulation of protein synthesis in crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Key, J.L.; Nagao, R.T.

    1991-06-01

    The major research activities accomplished during the renewal period focused on defining regulatory mechanisms operative in the heat shock (HS) response and assessing the mechanism of HS-induced thermotolerance in Arabidopsis. HS gene regulation was studied by transcriptional run-off assays, and self regulation of heat shock protein (hsp) levels and synthesis was studied through use of amino acid analogs and protein synthesis inhibitors. Also studied were subcellular localization of hsps during HS and HS recovery, characterization of membrane bound hsps and their effects on membrane proton transport, and the influence of over- or underexpression of HS mRNAs and hsps plant phenotype using transgenic plants. In addition, hsp70 and hsp83 cDNAs/genes are being characterized and their expression patterns will be evaluated. 10 refs. (MHB)

  11. Crop resistance traits modify the effects of an aboveground herbivore, brown planthopper, on soil microbial biomass and nematode community via changes to plant performance.

    NARCIS (Netherlands)

    Huang, J.; Liu, M.; Chen, F.; Griffiths, B.S.; Chen, X.; Johnson, S.N.; Hu, F.

    2012-01-01

    Plant-mediated effects of aboveground herbivory on the belowground ecosystem are well documented, but less attention has been paid to agro-ecosystems and in particular how crop cultivars with different traits (i.e. resistance to pests) shape such interactions. A fully factorial experiment was

  12. Genetic basis and detection of unintended effects in genetically modified crop plants

    OpenAIRE

    Ladics, Gregory S.; Bartholomaeus, Andrew; Bregitzer, Phil; Doerrer, Nancy G.; Gray, Alan; Holzhauser, Thomas; Jordan, Mark; Keese, Paul; Kok, Esther; Macdonald, Phil; Parrott, Wayne; Privalle, Laura; Raybould, Alan; Rhee, Seung Yon; Rice, Elena

    2015-01-01

    In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled ?Genetic Basis of Unintended Effects in Modified Plants? was held in Ottawa, Canada, bringing together over 75 scientists from academia, government, and the agro-biotech industry. The objectives of the meeting were to explore current knowledge and identify areas requiring further study on unintended effects ...

  13. Mite pests in plant crops: Current issues, inovative approaches and possibilities for controlling them

    OpenAIRE

    Petanović Radmila; Marčić Dejan; Vidović Biljana

    2010-01-01

    In the middle of the last century, mites moved into the focus of attention as pests relevant to agriculture, forestry and landscape horticulture, presumably in direct reaction to the 'green revolution' that involved plant cultivation in large-plot monocropping systems, improved methods of cultivation, selection of high-yielding cultivars and intensified use of pesticides and mineral fertilizers. Agroecosystems in which phytophagous mites have become harmful organisms...

  14. Control of insect vectors and plant viruses in protected crops by novel pyrethroid-treated nets.

    Science.gov (United States)

    Dáder, Beatriz; Legarrea, Saioa; Moreno, Aránzazu; Plaza, María; Carmo-Sousa, Michele; Amor, Fermín; Viñuela, Elisa; Fereres, Alberto

    2015-10-01

    Long-lasting insecticide-treated nets (LLITNs) constitute a novel alternative that combines physical and chemical tactics to prevent insect access and the spread of insect-transmitted plant viruses in protected enclosures. This approach is based on a slow-release insecticide-treated net with large hole sizes that allow improved ventilation of greenhouses. The efficacy of a wide range of LLITNs was tested under laboratory conditions against Myzus persicae, Aphis gossypii and Bemisia tabaci. Two nets were selected for field tests under a high insect infestation pressure in the presence of plants infected with Cucumber mosaic virus and Cucurbit aphid-borne yellows virus. The efficacy of Aphidius colemani, a parasitoid commonly used for biological control of aphids, was studied in parallel field experiments. LLITNs produced high mortality of aphids, although their efficacy decreased over time with sun exposure. Certain nets excluded whiteflies under laboratory conditions; however, they failed in the field. Nets effectively blocked the invasion of aphids and reduced the incidence of viruses in the field. The parasitoid A. colemani was compatible with LLITNs. LLITNs of appropriate mesh size can become a very valuable tool in combination with biocontrol agents for additional protection against insect vectors of plant viruses under IPM programmes. © 2014 Society of Chemical Industry.

  15. Evolution of RAD- and DIV-Like Genes in Plants

    Directory of Open Access Journals (Sweden)

    Ao Gao

    2017-09-01

    Full Text Available Developmental genetic studies of Antirrhinum majus demonstrated that two transcription factors from the MYB gene family, RADIALIS (RAD and DIVIRICATA (DIV, interact through antagonism to regulate floral dorsoventral asymmetry. Interestingly, similar antagonistic interaction found among proteins of FSM1 (RAD-like and MYBI (DIV-like in Solanum lycopersicum is involved in fruit development. Here, we report the reconstruction of the phylogeny of I-box-like and R-R-type clades, where RAD- and DIV-like genes belong, respectively. We also examined the homology of these antagonistic MYB proteins using these phylogenies. The results show that there are likely three paralogs of RAD-/I-box-like genes, RAD1, RAD2, and RAD3, which originated in the common ancestor of the core eudicots. In contrast, R-R-type sequences fall into two major clades, RR1 and RR2, the result of gene duplication in the common ancestor of both monocots and dicots. RR1 was divided into clades RR1A, RR1B, and RR1C, while RR2 was divided into clades RR2A/DIV1, RR2B/DIV2, and RR2C/DIV3. We demonstrate that among similar antagonistic interactions in An. Majus and So. lycopersicum, RAD-like genes originate from the RAD2 clade, while DIV-like genes originate from distantly related paralogs of the R-R-type lineage. The phylogenetic analyses of these two MYB clades lay the foundation for future comparative studies including testing the evolution of the antagonistic relationship of proteins.

  16. Effects of Moringa oleifera LAM, Leguminous Plants and NPK Fertilizer Comparatively on Orange Fleshed Sweet Potato in Alley Cropping System

    Directory of Open Access Journals (Sweden)

    IN Abdullahi

    2014-09-01

    Full Text Available The research work conducted at the Teaching and Research Farm of University of Abuja was aimed at assessing the effect of Moringa oleifera, selected leguminous plants and inorganic fertilizer on the performance of orange fleshed sweet potato in Alley Cropping System. Randomized Complete Block Design (RCBD using five treatments with three replications was applied. Data collected include: percentage survival of sweet potato, length per vine (cm, number of leaves per vine, leaf area of sweet potato, weed dry matter (g/m2, yield of sweet potato roots. Highest number of leaves (28 per plant was recorded in the control plot while the plots with NPK fertilizer had the highest length per vine (94.55cm though not significantly (p>0.05 different from others. Higher percent survival (88% of sweet potato was recorded from control plots. Stands grown in Arachis hypogeae plots produced the highest leaf area (0.202m2 while plots in which NPK fertilizer was applied experienced highest weed dry matter (4.083g/m2 although highest root yield (1.2t/ha was recorded from the plots with NPK fertilizer. DOI: http://dx.doi.org/10.3126/ije.v3i3.11061 International Journal of Environment Vol.3(3 2014: 24-35

  17. Impacts of silver nanoparticles on bacterial species B. subtilis and E. coli and the major crop plant Z. mays

    Science.gov (United States)

    Doody, Michael A.

    This thesis examines the impacts of citrate-coated silver nanoparticles (c-AgNPs) on two species of bacteria (Bacillus subtilis and Escherichia coli), the major crop plant Zea mays, and the beneficial plant-microbe relationship between Z. mays and B. subtilis. AgNPs are an increasing component of antimicrobial consumer, industrial, and military products. This has led to widespread scientific concern for the ecological safety outside their intended use. An overview of their history, use, and toxicity was used to inform the design of experiments and resulting data. Growth inhibition and sub-lethal toxic effects were used to assess the effects of c-AgNP exposure to bacteria. Similar analytical methods were used to quantify the response of Z. mays to c-AgNP exposure. Results showed that exposure to c-AgNP significantly reduced the growth of bacterial populations and alters their growth kinetics. Z. mays experienced significant sub-lethal effects due to exposure, including reduced root length and biomass, and hyper-accumulated Ag in root tissues. Beneficial interactions between B. subtilis and Z. mays were reduced as both species suffered sub-lethal effects of exposure to c-AgNPs.

  18. Inside the trap: gland morphologies, digestive enzymes, and the evolution of plant carnivory in the Caryophyllales⋆

    Science.gov (United States)

    Renner, Tanya; Specht, Chelsea D

    2013-01-01

    The digestion of prey by carnivorous plants is determined in part by suites of enzymes that are associated with morphologically and anatomically diverse trapping mechanisms. Chitinases represent a group of enzymes known to be integral to effective plant carnivory. In non-carnivorous plants, chitinases commonly act as pathogenesis-related proteins, which are either induced in response to insect herbivory and fungal elicitors, or constitutively expressed in tissues vulnerable to attack. In the Caryophyllales carnivorous plant lineage, multiple classes of chitinases are likely involved in both pathogenic response and digestion of prey items. We review what is currently known about trap morphologies, provide an examination of the diversity, roles, and evolution of chitinases, and examine how herbivore and pathogen defense mechanisms may have been coopted for plant carnivory in the Caryophyllales. PMID:23830995

  19. Genome Size Diversity and Its Impact on the Evolution of Land Plants

    Directory of Open Access Journals (Sweden)

    Jaume Pellicer

    2018-02-01

    Full Text Available Genome size is a biodiversity trait that shows staggering diversity across eukaryotes, varying over 64,000-fold. Of all major taxonomic groups, land plants stand out due to their staggering genome size diversity, ranging ca. 2400-fold. As our understanding of the implications and significance of this remarkable genome size diversity in land plants grows, it is becoming increasingly evident that this trait plays not only an important role in shaping the evolution of plant genomes, but also in influencing plant community assemblages at the ecosystem level. Recent advances and improvements in novel sequencing technologies, as well as analytical tools, make it possible to gain critical insights into the genomic and epigenetic mechanisms underpinning genome size changes. In this review we provide an overview of our current understanding of genome size diversity across the different land plant groups, its implications on the biology of the genome and what future directions need to be addressed to fill key knowledge gaps.

  20. Dissecting the Phenotypic Components of Crop Plant Growth and Drought Responses Based on High-Throughput Image Analysis[W][OPEN

    Science.gov (United States)

    Chen, Dijun; Neumann, Kerstin; Friedel, Swetlana; Kilian, Benjamin; Chen, Ming; Altmann, Thomas; Klukas, Christian

    2014-01-01

    Significantly improved crop varieties are urgently needed to feed the rapidly growing human population under changing climates. While genome sequence information and excellent genomic tools are in place for major crop species, the systematic quantification of phenotypic traits or components thereof in a high-throughput fashion remains an enormous challenge. In order to help bridge the genotype to phenotype gap, we developed a comprehensive framework for high-throughput phenotype data analysis in plants, which enables the extraction of an extensive list of phenotypic traits from nondestructive plant imaging over time. As a proof of concept, we investigated the phenotypic components of the drought responses of 18 different barley (Hordeum vulgare) cultivars during vegetative growth. We analyzed dynamic properties of trait expression over growth time based on 54 representative phenotypic features. The data are highly valuable to understand plant development and to further quantify growth and crop performance features. We tested various growth models to predict plant biomass accumulation and identified several relevant parameters that support biological interpretation of plant growth and stress tolerance. These image-based traits and model-derived parameters are promising for subsequent genetic mapping to uncover the genetic basis of complex agronomic traits. Taken together, we anticipate that the analytical framework and analysis results presented here will be useful to advance our views of phenotypic trait components underlying plant development and their responses to environmental cues. PMID:25501589

  1. The genetic architecture of ecological adaptation: intraspecific variation in host plant use by the lepidopteran crop pest Chloridea virescens.

    Science.gov (United States)

    Oppenheim, Sara J; Gould, Fred; Hopper, Keith R

    2018-03-01

    Intraspecific variation in ecologically important traits is a cornerstone of Darwin's theory of evolution by natural selection. The evolution and maintenance of this variation depends on genetic architecture, which in turn determines responses to natural selection. Some models suggest that traits with complex architectures are less likely to respond to selection than those with simple architectures, yet rapid divergence has been observed in such traits. The simultaneous evolutionary lability and genetic complexity of host plant use in the Lepidopteran subfamily Heliothinae suggest that architecture may not constrain ecological adaptation in this group. Here we investigate the response of Chloridea virescens, a generalist that feeds on diverse plant species, to selection for performance on a novel host, Physalis angulata (Solanaceae). P. angulata is the preferred host of Chloridea subflexa, a narrow specialist on the genus Physalis. In previous experiments, we found that the performance of C. subflexa on P. angulata depends on many loci of small effect distributed throughout the genome, but whether the same architecture would be involved in the generalist's adoption of P. angulata was unknown. Here we report a rapid response to selection in C. virescens for performance on P. angulata, and establish that the genetic architecture of intraspecific variation is quite similar to that of the interspecific differences in terms of the number, distribution, and effect sizes of the QTL involved. We discuss the impact of genetic architecture on the ability of Heliothine moths to respond to varying ecological selection pressures.

  2. Governing the GM crop revolution

    OpenAIRE

    Paarlberg, Robert L.

    2000-01-01

    Will developing countries adopt policies that promote the planting of genetically modified (GM) crops, or will they select policies that slow the spread of the GM crop revolution? The evidence so far is mixed. In some prominent countries such as China, policies are in place that encourage the independent development and planting of GM crops. Yet in a number of other equally prominent countries the planting of GM crops is not yet officially approved. The inclination of developing countries to ...

  3. Host Resistance and Temperature-Dependent Evolution of Aggressiveness in the Plant Pathogen Zymoseptoria tritici

    Directory of Open Access Journals (Sweden)

    Fengping Chen

    2017-06-01

    Full Text Available Understanding how habitat heterogeneity may affect the evolution of plant pathogens is essential to effectively predict new epidemiological landscapes and manage genetic diversity under changing global climatic conditions. In this study, we explore the effects of habitat heterogeneity, as determined by variation in host resistance and local temperature, on the evolution of Zymoseptoria tritici by comparing the aggressiveness development of five Z. tritici populations originated from different parts of the world on two wheat cultivars varying in resistance to the pathogen. Our results show that host resistance plays an important role in the evolution of Z. tritici. The pathogen was under weak, constraining selection on a host with quantitative resistance but under a stronger, directional selection on a susceptible host. This difference is consistent with theoretical expectations that suggest that quantitative resistance may slow down the evolution of pathogens and therefore be more durable. Our results also show that local temperature interacts with host resistance in influencing the evolution of the pathogen. When infecting a susceptible host, aggressiveness development of Z. tritici was negatively correlated to temperatures of the original collection sites, suggesting a trade-off between the pathogen’s abilities of adapting to higher temperature and causing disease and global warming may have a negative effect on the evolution of pathogens. The finding that no such relationship was detected when the pathogen infected the partially resistant cultivars indicates the evolution of pathogens in quantitatively resistant hosts is less influenced by environments than in susceptible hosts.

  4. Early Detection of Crop Injury from Glyphosate on Soybean and Cotton Using Plant Leaf Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-02-01

    Full Text Available In this paper, we aim to detect crop injury from glyphosate, a herbicide, by both traditionally used spectral indices and newly extracted features with leaf hyperspectral reflectance data for non-Glyphosate-Resistant (non-GR soybean and non-GR cotton. The new features were extracted by canonical analysis technique, which could provide the largest separability to distinguish the injured leaves from the healthy ones. Spectral bands used for constructing these new features were selected based on the sensitivity analysis results of a physically-based leaf radiation transfer model (leaf optical PROperty SPECTra model, PROSPECT, which could help extend the effectiveness of these features to a wide range of leaf structures and growing conditions. This approach has been validated with greenhouse measured data acquired in glyphosate treatment experiments. Results indicated that glyphosate injury could be detected by NDVI (Normalized Difference Vegetation Index, RVI (Ratio Vegetation Index, SAVI (Soil Adjusted Vegetation Index, and DVI (Difference Vegetation Index in 48 h After the Treatment (HAT for soybean and in 72 HAT for cotton, but the other spectral indices either showed little use for separation, or did not show consistent separation for healthy and injured soybean and cotton. Compared with the traditional spectral indices, the new features were more feasible for the early detection of glyphosate injury, with leaves sprayed with a higher rate of glyphosate solution having larger feature values. This trend became more and more pronounced with time. Leaves sprayed with different glyphosate rates showed some separability 24 HAT using the new features and could be totally distinguished at and beyond 48 HAT for both soybean and cotton. These findings demonstrated the feasibility of applying leaf hyperspectral reflectance measurements for the early detection of glyphosate injury using these newly proposed features.

  5. Influence of Seeding Ratio, Planting Date, and Termination Date on Rye-Hairy Vetch Cover Crop Mixture Performance under Organic Management

    Science.gov (United States)

    Lawson, Andrew; Cogger, Craig; Bary, Andy; Fortuna, Ann-Marie

    2015-01-01

    Cover crop benefits include nitrogen accumulation and retention, weed suppression, organic matter maintenance, and reduced erosion. Organic farmers need region-specific information on winter cover crop performance to effectively integrate cover crops into their crop rotations. Our research objective was to compare cover crop seeding mixtures, planting dates, and termination dates on performance of rye (Secale cereale L.) and hairy vetch (Vicia villosa Roth) monocultures and mixtures in the maritime Pacific Northwest USA. The study included four seed mixtures (100% hairy vetch, 25% rye-75% hairy vetch, 50% rye-50% hairy vetch, and 100% rye by seed weight), two planting dates, and two termination dates, using a split-split plot design with four replications over six years. Measurements included winter ground cover; stand composition; cover crop biomass, N concentration, and N uptake; and June soil NO3--N. Rye planted in mid-September and terminated in late April averaged 5.1 Mg ha-1 biomass, whereas mixtures averaged 4.1 Mg ha-1 and hairy vetch 2.3 Mg ha-1. Delaying planting by 2.5 weeks reduced average winter ground cover by 65%, biomass by 50%, and cover crop N accumulation by 40%. Similar reductions in biomass and N accumulation occurred for late March termination, compared with late April termination. Mixtures had less annual biomass variability than rye. Mixtures accumulated 103 kg ha-1 N and had mean C:N ratio <17:1 when planted in mid-September and terminated in late April. June soil NO3--N (0 to 30 cm depth) averaged 62 kg ha-1 for rye, 97 kg ha-1 for the mixtures, and 119 kg ha-1 for hairy vetch. Weeds comprised less of the mixtures biomass (20% weeds by weight at termination) compared with the monocultures (29%). Cover crop mixtures provided a balance between biomass accumulation and N concentration, more consistent biomass over the six-year study, and were more effective at reducing winter weeds compared with monocultures. PMID:26080008

  6. Assessing the levels of food shortage using the traffic light metaphor by analyzing the gathering and consumption of wild food plants, crop parts and crop residues in Konso, Ethiopia

    Science.gov (United States)

    2012-01-01

    Background Humanitarian relief agencies use scales to assess levels of critical food shortage to efficiently target and allocate food to the neediest. These scales are often labor-intensive. A lesser used approach is assessing gathering and consumption of wild food plants. This gathering per se is not a reliable signal of emerging food stress. However, the gathering and consumption of some specific plant species could be considered markers of food shortage, as it indicates that people are compelled to eat very poor or even health-threatening food. Methods We used the traffic light metaphor to indicate normal (green), alarmingly low (amber) and fully depleted (red) food supplies and identified these conditions for Konso (Ethiopia) on the basis of wild food plants (WFPs), crop parts (crop parts not used for human consumption under normal conditions; CPs) and crop residues (CRs) being gathered and consumed. Plant specimens were collected for expert identification and deposition in the National Herbarium. Two hundred twenty individual households free-listed WFPs, CPs, and CRs gathered and consumed during times of food stress. Through focus group discussions, the species list from the free-listing that was further enriched through key informants interviews and own field observations was categorized into species used for green, amber and red conditions. Results The study identified 113 WFPs (120 products/food items) whose gathering and consumption reflect the three traffic light metaphors: red, amber and green. We identified 25 food items for the red, 30 food items for the amber and 65 food items for the green metaphor. We also obtained reliable information on 21 different products/food items (from 17 crops) normally not consumed as food, reflecting the red or amber metaphor and 10 crop residues (from various crops), plus one recycled stuff which are used as emergency foods in the study area clearly indicating the severity of food stress (red metaphor) households are

  7. Assessing the levels of food shortage using the traffic light metaphor by analyzing the gathering and consumption of wild food plants, crop parts and crop residues in Konso, Ethiopia

    Directory of Open Access Journals (Sweden)

    Ocho Dechassa

    2012-08-01

    Full Text Available Abstract Background Humanitarian relief agencies use scales to assess levels of critical food shortage to efficiently target and allocate food to the neediest. These scales are often labor-intensive. A lesser used approach is assessing gathering and consumption of wild food plants. This gathering per se is not a reliable signal of emerging food stress. However, the gathering and consumption of some specific plant species could be considered markers of food shortage, as it indicates that people are compelled to eat very poor or even health-threatening food. Methods We used the traffic light metaphor to indicate normal (green, alarmingly low (amber and fully depleted (red food supplies and identified these conditions for Konso (Ethiopia on the basis of wild food plants (WFPs, crop parts (crop parts not used for human consumption under normal conditions; CPs and crop residues (CRs being gathered and consumed. Plant specimens were collected for expert identification and deposition in the National Herbarium. Two hundred twenty individual households free-listed WFPs, CPs, and CRs gathered and consumed during times of food stress. Through focus group discussions, the species list from the free-listing that was further enriched through key informants interviews and own field observations was categorized into species used for green, amber and red conditions. Results The study identified 113 WFPs (120 products/food items whose gathering and consumption reflect the three traffic light metaphors: red, amber and green. We identified 25 food items for the red, 30 food items for the amber and 65 food items for the green metaphor. We also obtained reliable information on 21 different products/food items (from 17 crops normally not consumed as food, reflecting the red or amber metaphor and 10 crop residues (from various crops, plus one recycled stuff which are used as emergency foods in the study area clearly indicating the severity of food stress (red metaphor

  8. Assessing the levels of food shortage using the traffic light metaphor by analyzing the gathering and consumption of wild food plants, crop parts and crop residues in Konso, Ethiopia.

    Science.gov (United States)

    Ocho, Dechassa Lemessa; Struik, Paul C; Price, Lisa L; Kelbessa, Ensermu; Kolo, Koshana

    2012-08-07

    Humanitarian relief agencies use scales to assess levels of critical food shortage to efficiently target and allocate food to the neediest. These scales are often labor-intensive. A lesser used approach is assessing gathering and consumption of wild food plants. This gathering per se is not a reliable signal of emerging food stress. However, the gathering and consumption of some specific plant species could be considered markers of food shortage, as it indicates that people are compelled to eat very poor or even health-threatening food. We used the traffic light metaphor to indicate normal (green), alarmingly low (amber) and fully depleted (red) food supplies and identified these conditions for Konso (Ethiopia) on the basis of wild food plants (WFPs), crop parts (crop parts not used for human consumption under normal conditions; CPs) and crop residues (CRs) being gathered and consumed. Plant specimens were collected for expert identification and deposition in the National Herbarium. Two hundred twenty individual households free-listed WFPs, CPs, and CRs gathered and consumed during times of food stress. Through focus group discussions, the species list from the free-listing that was further enriched through key informants interviews and own field observations was categorized into species used for green, amber and red conditions. The study identified 113 WFPs (120 products/food items) whose gathering and consumption reflect the three traffic light metaphors: red, amber and green. We identified 25 food items for the red, 30 food items for the amber and 65 food items for the green metaphor. We also obtained reliable information on 21 different products/food items (from 17 crops) normally not consumed as food, reflecting the red or amber metaphor and 10 crop residues (from various crops), plus one recycled stuff which are used as emergency foods in the study area clearly indicating the severity of food stress (red metaphor) households are dealing with. Our traffic

  9. Comparative genomic paleontology across plant kingdom reveals the dynamics of TE-driven genome evolution.

    Science.gov (United States)

    El Baidouri, Moaine; Panaud, Olivier

    2013-01-01

    Long terminal repeat-retrotransposons (LTR-RTs) are the most abundant class of transposable elements (TEs) in plants. They strongly impact the structure, function, and evolution of their host genome, and, in particular, their role in genome size variation has been clearly established. However, the dynamics of the process through which LTR-RTs have differentially shaped plant genomes is still poorly understood because of a lack of comparative studies. Using a new robust and automated family classification procedure, we exhaustively characterized the LTR-RTs in eight plant genomes for which a high-quality sequence is available (i.e., Arabidopsis thaliana, A. lyrata, grapevine, soybean, rice, Brachypodium dystachion, sorghum, and maize). This allowed us to perform a comparative genome-wide study of the retrotranspositional landscape in these eight plant lineages from both monocots and dicots. We show that retrotransposition has recurrently occurred in all plant genomes investigated, regardless their size, and through bursts, rather than a continuous process. Moreover, in each genome, only one or few LTR-RT families have been active in the recent past, and the difference in genome size among the species studied could thus mostly be accounted for by the extent of the latest transpositional burst(s). Following these bursts, LTR-RTs are efficiently eliminated from their host genomes through recombination and deletion, but we show that the removal rate is not lineage specific. These new findings lead us to propose a new model of TE-driven genome evolution in plants.

  10. The Heavy Links between Geological Events and Vascular Plants Evolution: A Brief Outline.

    Science.gov (United States)

    Pio