Download or read book Understanding the Genetic Basis of Symbiotic Nitrogen Fixation in Common Bean Phaseolus Vulgaris L Using Genomic and Transcriptomic Analyses written by Kelvin Kamfwa and published by . This book was released on 2015 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Symbiotic Nitrogen Fixation written by P. Graham and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past three decades there has been a large amount of research on biological nitrogen fixation, in part stimulated by increasing world prices of nitrogen-containing fertilizers and environmental concerns. In the last several years, research on plant--microbe interactions, and symbiotic and asymbiotic nitrogen fixation has become truly interdisciplinary in nature, stimulated to some degree by the use of modern genetic techniques. These methodologies have allowed us to make detailed analyses of plant and bacterial genes involved in symbiotic processes and to follow the growth and persistence of the root-nodule bacteria and free-living nitrogen-fixing bacteria in soils. Through the efforts of a large number of researchers we now have a better understanding of the ecology of rhizobia, environmental parameters affecting the infection and nodulation process, the nature of specificity, the biochemistry of host plants and microsymbionts, and chemical signalling between symbiotic partners. This volume gives a summary of current research efforts and knowledge in the field of biological nitrogen fixation. Since the research field is diverse in nature, this book presents a collection of papers in the major research area of physiology and metabolism, genetics, evolution, taxonomy, ecology, and international programs.
Download or read book The Common Bean Genome written by Marcelino Pérez de la Vega and published by Springer. This book was released on 2017-12-20 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides insights into the genetics and the latest advances in genomics research on the common bean, offering a timely overview of topics that are pertinent for future developments in legume genomics. The common bean (Phaseolus vulgaris L.) is the most important grain legume crop for food consumption worldwide, as well as a model for legume research, and the availability of the genome sequence has completely changed the paradigm of the ongoing research on the species. Key topics covered include the numerous genetic and genomic resources, available tools, the identified genes and quantitative trait locus (QTL) identified, and there is a particular emphasis on domestication. It is a valuable resource for students and researchers interested in the genetics and genomics of the common bean and legumes in general.
Download or read book Genetics and breeding for nitrogen fixation in common bean Phaseolus vulgaris written by Walter Quadros Ribeiro and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Domestication Fertilization and Nodulation written by Gwendolyn Fry and published by . This book was released on 2024 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Phaseolus vulgaris L. (Latin American common bean) is a leguminous crop that is significant in the life histories of both human civilization and nitrogen-fixing bacteria called rhizobia. These associations are evident from the impacts they have left on the genome of the common bean. As a legume, the common bean has several genes that code for the initiation and maintenance of mutualistic endosymbiosis with rhizobia. Over the course of its domestication and cultivation, the common bean has also undergone simultaneous artificial selection and multiple bottlenecks. As it exists in commercial agriculture, crops of common bean lack within-population genetic diversity and are widely considered poor at facilitating nitrogen fixation. Recent studies suggest nitrogen fertilization to be key in the decline of nodulation in cultivars of common bean. In addition, preliminary research suggests that wild lineages of bean have greater numbers of nodules. However, these data do not directly compare proxies of nitrogen fixation, like nodulation, with genotype and the presence of nitrogen fertilizer. I hypothesized that bean accession would be a more significant factor than nitrogen presence in determining the ability to facilitate nitrogen fixation. Through a randomized block greenhouse experiment that observed the variables of accession and nitrogen treatment, I found that both nitrogen fertilization and genotype were significant contributors to root:shoot ratio, nodule number, and chlorophyll content index (CCI) in common bean. However, bean genotype was more significant in determining ability to facilitate nitrogen fixation.
Download or read book Toward Genomics based Breeding in Phaseolus Vulgaris and Quantitative Trait Locus Mapping of Angular Leaf Spot Resistance written by Tamara Iva Miller and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The common bean (Phaseolus vulgaris L.) is consumed by millions of people worldwide and is a staple source of protein, starch and micronutrients. Common bean production across the world is affected by abiotic and biotic stresses that limit the growth and yield of this important crop. Efforts to breed improved common bean for dissemination to farmers and consumers in East Africa is underway in several breeding programs worldwide. Improvement on agronomic and consumer traits such as disease resistance can be greatly aided by the application of next generation sequencing technologies. With the decreasing cost of DNA sequencing, genomic re-sequencing of diverse common bean accessions facilitates marker- assisted breeding that can be used to speed the creation of new common bean cultivars. Marker-assisted selection (MAS) is an important aspect of modern bean breeding that seeks to utilize genetic markers to select individuals with improved agronomic and consumer traits. For example, breeders in the African Bean Consortium seek to introgress known genetic loci conferring resistance to multiple diseases into bean genetic backgrounds with preferred seed and agronomic characteristics. However, the usefulness of markers is dependent on whether they are polymorphic in the specific parents of the breeding program. Often genetic markers identified in a specific plant population are not useful for marker assisted selection among a different set of bean parents, which necessitates identification of novel markers linked to the genes of interest that are polymorphic among breeding parents. One disease that greatly affects common bean production in humid tropical and sub-tropical growing regions is Angular Leaf Spot (ALS; caused by the foliar fungus Pseudocercospora griseola Sacc.). Marker assisted breeding is being used in multiple different bean breeding programs to improve the resistance of adapted cultivars to ALS. The ALS resistance locus, Phg-2, is an important resistance locus used to improve plant resistance to Angular Leaf Spot in South America and Pan Africa, however in the case of the African Bean Consortium breeding programs in East Africa, certain bean parents used for breeding were monomorphic for the original marker used to perform marker assisted selection of Phg-2. In order to facilitate marker assisted selection of Phg-2 in specific breeding parents used in the Uganda bean improvement program, an alternative, co-dominant, marker linked to the Phg-2 ALS resistance locus was developed (Chapter 1). A new marker, g796, was identified which is polymorphic among the breeding parents; its co-segregation was confirmed in a segregating F2 population derived from the cross between French bean variety Amy and the ALS resistance donor, Mexico 54. This work was conducted in collaboration with Stephen Kimno and Esther Arunga at Embu University, Kenya, as well as other members of the African Bean Consortium bean breeding programs in Tanzania, Uganda, and Ethiopia. The application of DNA sequencing to marker-assisted breeding and crop improvement is rapidly becoming common in the development of improved bean varieties. A nearly complete reference genome and transcriptome for Phaseolus vulgaris was released in 2014 and newly resequenced genomes of diverse bean accessions are being developed for the purpose of marker assisted breeding. In Chapter 2, whole-genome resequencing of 29 bean accessions, including accessions commonly used as breeding parents, was carried out in collaboration with the Ratz lab at the International Center for Tropical Agriculture (CIAT, Colombia). Genetic diversity analysis was performed in order to access the evolutionary relationships between the sequenced bean genomes. Data generated by this work was made available to the larger bean research community and will be used by breeders and geneticists to perform marker-assisted selection and genetic analysis in the future. Angular leaf spot (ALS) occurs throughout Eastern and Southern Africa (as well as other parts of the world) and can cause yield losses up to 80% in environments that favor the disease. ALS is caused by the fungal pathogen, Pseudocercospora griseola, a highly diverse pathogen with many different races that infect diverse types of bean hosts. Growing crop cultivars with genetic resistance to the disease is one of the most effective measures for farmers to reduce crop losses due to ALS. The landrace Mexico 54 is used as a donor for ALS resistance in East Africa and marker-assisted selection of the Phg-2 ALS resistance locus from Mexico 54 is underway in multiple breeding programs in order to increase the resistance of adapted bean germplasm in East Africa and Brazil. Previous allelism tests between different ALS resistance donors suggested additional resistance loci exist in Mexico 54 besides the Phg-2 locus and were named Phg-5 and Phg-6. The genomic locations of the proposed Phg-5 and Phg-6 resistance genes in Mexico 54 have never been investigated, however, the existence of multiple resistance loci in Mexico 54 is likely the cause of its high level of resistance to ALS on multiple continents. In Chapter 3, a biparental mapping population consisting of 167 F8 recombinant inbred lines (RIL) was derived from a cross between Kablanketi, a preferred bean market type in Tanzania, and Mexico 54 in order to map additional quantitative trait loci that confer resistance to ALS in Mexico 54. The identification of novel ALS resistance loci will aid breeders to develop resistant cultivars as well as provide a greater understanding of the genetic diversity that influences resistance to ALS.
Download or read book Genetics and Breeding for Nitrogen Fixation in Common Bean Phaseolus Vulgaris written by W. Q Ribeiro Junior and published by . This book was released on 1996 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: An initial selection for nitrogen fixation was made from 77 genotypes of common bean (Phaseolus vulgaris) adapted to Goias state, Brazil, comparing them with control genotypes with know symbiotic capacity. After several selections, the outstanding genotypes for nitrogen fixation produced 1314 kg/ha (almost three times the Brazilian average), but the treatment with mineral nitrogen was superior, suggesting the necessity of a breeding project for nitrogen fixation. Two genotypes were selected based on their capacity to fix nitrogen, productivity without nitrogen fertilizers, adaptability to Goias state and other agronomic characteristics. The two parents were evaluated in semi-controlled conditions for symbiotic capacity. The genotype WBR2255 showed better symbiotic efficiency, nodule dry weight, weight per nodule, later nodule senescence and greater tolerance to mineral nitrogen in the latter stages of growth than A295.
Download or read book Metabolome Analyses written by Seetharaman Vaidyanathan and published by Springer Science & Business Media. This book was released on 2006-03-20 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metabolome analysis is now recognized as a crucial component of functional genomic and systems biology investigations. Innovative approaches to the study of metabolic regulation in microbial, plant and animal systems are increasingly facilitating the emergence of systems approaches in biology. This book highlights analytical and bioinformatics strategies now available for investigating metabolic networks in microbial, plant and animal systems. The contributing authors are world leaders in this field and they present an unambiguous case for pursuing metabolome analysis as a means to attain a systems level understanding of complex biological systems.
Download or read book Exploring the Genetic Basis of Seed Coat and Nutritional Traits in Common Bean and Maize written by Di Wu and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Common bean (Phaseolus vulgaris L.) and maize (Zea mays L.) are two crops central to indigenous America and of great global agricultural importance. However, the landraces of common bean are largely underrepresented in genebanks, and despite the importance of elements and tocochromanols to plant function and human health, there are still gaps in the understanding of the transport and accumulation of these nutrients in maize grain. Through the array of research tools offered by the field of population genomics and quantitative genetics, this dissertation works towards addressing such gaps. The genomic characterization of ~ 300 accessions of common bean from Native Seeds/SEARCH collected from southwestern US and northwestern Mexico established it as a unique and underrepresented resource that contained important genetic diversity. Five genes encoding MYB transcription factors proximal to the C locus were identified, which is a complex genomic region responsible for the primary control of seed coat patterns. An additional novel association for partial colored seed coats was identified on chromosome 10. Through genome-wide association studies (GWAS) with high density SNP set and the 1500-line Ames panel, I investigated the genetic basis of natural variation for the concentration of 11 elements in grain and identified a total of nine causal genes encoding metal chelator or transporter. Notably, two novel associations were reported between rte2 and irt1 with boron and nickel, respectively, and a potential biofortification target, nas5, was identified for both zinc and iron. Similar moderate predictive abilities (0.33-0.53) were obtained for the 11 grain elemental phenotypes with Bayesian Ridge Regression (BRR) and BayesB. However, BayesB, allowing SNPs to have large effects, had a better fit to the genetic architecture of nickel, molybdenum, and copper, thus outperforming BRR by 4-10%. Finally, through GWAS, transcriptome-wide association studies (TWAS) and expression quantitative trait locus (eQTL) mapping, 13 causal genes that were mostly under strong cis-regulatory control were identified to associate with tocochromanol levels in maize grain. Four genes were pinpointed to be associated with tocochromanol concentrations in maize grain, including vte5, dxs1, vte7, and samt. Overall, this dissertation demonstrates a multidisciplinary approach to characterize a unique common bean collection and the genetic control of its seed coat pattern, and provides a comprehensive assessment of the genetic basis of nutritional qualities in maize grain.
Download or read book Improvement of Common Bean Phaseolus Vulgaris Nodulation by Selected Rhizobial Strain from Egyptian Soils Through Genotypic Characterization Symbiotic Effectiveness and Competitiveness Under Salt Stress Conditions written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To maximize the symbiotic nitrogen fixation of common bean (Phaseolus vulgaris) under egyptian soil conditions, twelve rhizobial isolates were isolated from root nodulated common bean. These isolates were physiologiacl characterized to test the more effeicient strains in nitrogen fixation, to select strains more adapted to environmetal stresses such as salinity, alkalinity, temperature. The adapted strains were selected to study the competitiveness of these strains against the standard strain CIAT 899 marked with gus gene under normal conditions, stress of salinity and stress of alkalinity. These strains were also characterized using molecular biology techniques such as REP-PCR, ARDRA of 16S and 23S rDNA, plasmid profiles analysis, sequencing of full length of 16S rDNA, hybridization with nifH gene and amplification of nodC gene. Strain EBRI 26 and Sinorhizobium meliloti strain 2010 were selected as salt tolerant strains to study the proteins involeved in salt tolerance by 2D proteom analysis and MALDI-Tof mass spectrometry.
Download or read book Exploring the Genetic Architecture and Improving Genomic Prediction Accuracy for Yield Mineral Concentration and Canning Quality Traits in Common Bean Phaseolus Vulgaris written by Paulo Cesar Izquierdo Romero and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dry bean (Phaseolus vulgaris L.) is the most important legumes for human consumption worldwide and is an important source of protein, vitamins, and micronutrients in the human diet. This research aimed to i) uncover the genetic architecture of yield, Fe bioavailability and seed micronutrient concentration, ii) characterize the genetic control of canning quality traits, and ii) assess the accuracy of genomic prediction models for yield and end-use quality traits. The genetic architecture of yield and seed micronutrient concentration was assessed through a combination of meta-QTL analyses integrating published studies over the last two decades in dry bean. A Gaussian mixture model was used to determine the number of distinct QTL in the meta-QTL analyses. Consistent meta-QTL over different genetic backgrounds and environments were identified, reducing the confidence interval compared with initial QTL. Furthermore, a genome-wide association (GWA) study with 295 lines of the yellow bean collection and 82 yellow recombinant inbred lines identified a major QTL for Fe bioavailability related to the ground factor P gene. A black breeding panel with 415 lines was evaluated for yield and canning quality traits in two growing seasons. Consistent associations for color retention, appearance and texture of canned beans were identified across years. Genomic prediction models provided moderate to high accuracy for end-use quality traits on the yellow and black populations. The genomic prediction accuracy was related to the heritability of each trait, and improvement of accuracy was observed for complex traits when secondary traits were included in the model, while for traits with major QTL, the use of associated markers as fixed effects increased prediction ability. The use of meta-QTL analyses and GWA in this study lays a foundation of the genetic control of yield and end-use quality traits and reveals the potential of genomic prediction for these traits in dry beans.
Download or read book Abiotic and Biotic Stress in Plants written by Arun Shanker and published by BoD – Books on Demand. This book was released on 2016-02-17 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact of global climate change on crop production has emerged as a major research priority during the past decade. Understanding abiotic stress factors such as temperature and drought tolerance and biotic stress tolerance traits such as insect pest and pathogen resistance in combination with high yield in plants is of paramount importance to counter climate change related adverse effects on the productivity of crops. In this multi-authored book, we present synthesis of information for developing strategies to combat plant stress. Our effort here is to present a judicious mixture of basic as well as applied research outlooks so as to interest workers in all areas of plant science. We trust that the information covered in this book would bridge the much-researched area of stress in plants with the much-needed information for evolving climate-ready crop cultivars to ensure food security in the future.
Download or read book Understanding the Genetic Components of Drought Tolerance in Common Bean Phaseolus Vulgaris L written by Isaac Onziga Dramadri and published by . This book was released on 2018 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metabolomics written by Wolfram Weckwerth and published by Springer Science & Business Media. This book was released on 2008-02-04 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metabolomics: Methods and Protocols examines the state-of-the-art in metabolomic analysis. Leading researchers in the field present protocols for the application of complementary analytical methods, such as gas chromatography-mass spectrometry (GC-MS). Metabolomics: Methods and Protocols contains forward-looking protocols, which provide the essential groundwork for future efforts in elucidating the structure of the unknowns detected in metabolomic studies.
Download or read book The Flagellar World written by Shin-Ichi Aizawa and published by Elsevier. This book was released on 2013-12-16 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Flagellar World is a unique publication. The product of years of research and data collection by the author, this book is a pictorial guide to flagella in a variety of organisms. Each EM image is accompanied by a short description of the system in each organism. These never-before-seen pictures represent a wide variety of flagella, including Legionella pneumophila, Escherichia coli, Pseudomonas aeruginosa, and many others. Researchers in microbiology, immunology, and parasitology will find this a fascinating and useful resource. A unique publication with many never before seen EM images of flagella A historical document of years of research on flagella Fills a specific niche that shows flagella in several varied organisms
Download or read book Evaluation of Genetic Diversity and Symbiotic Efficiency of Rhizobial Isolates Nodulating Common Bean Phaseolus Vulgaris L Grown Under Field Conditions in Limpopo South Africa written by and published by . This book was released on 2015 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen deficiency is recognized as the limiting factor for reduction in the yield of common bean in South Africa. The nitrogen fixing bacteria have the ability to enhance the plant growth and yield by fixing the atmospheric nitrogen and also play a role in fixing the problem. This study aims to examine diversity tolerance and symbiotic efficiency of rhizobial isolates.
Download or read book Legume Nitrogen Fixation in Soils with Low Phosphorus Availability written by Saad Sulieman and published by Springer. This book was released on 2017-06-10 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thoughtful and provocative book provides a concise, up-to-date presentation of how current and projected future phosphorus scarcity will affect legume growth and their symbiotic nitrogen-fixing capabilities. It is a timely examination of the physiological and molecular responses of nodules to phosphorous deficiency in attempt to identify common principles. Students and researchers in the many disciplines related to crop productivity will find this title an exciting contribution in the area of plant stress physiology. The knowledge in this volume can also aid plant breeders, particularly through new methods of genetic engineering, in developing unique and adaptive cultivars with higher symbiotic efficiency. The awareness of the rapidly rising world population must translate into a parallel increase in agricultural production in order to sustain the growing population both now and in the future. Hence, the demand for food crops to produce proteins and vegetable oil for human consumption is going to increase considerably during the coming years. The essential role of legumes in agriculture is well-recognized, given the abundant levels of proteins and oils found in plants along with their enormous contribution to the sustainability of agricultural systems and human health. The capacity of legumes to fix nitrogen (N2) in partnership with rhizobia provides an input-saving and resource-conserving alternative, thereby reducing the need for chemical fertilizers while enhancing overall crop productivity. The use of N2-fixing legumes to produce plant proteins results in a substantial decrease in the consumption of fossil fuels and therefore also in the agricultural effects to global warming. However, a major constraint to legume production is low soil phosphorus (P) availability, considering that an overwhelming majority of the world’s soils are classified as P-deficient. Low-P availability is especially problematic for legumes, since legume nodules responsible for N2 fixation have a high P requirement. Therefore, this book explains how nodule N2 fixation responds to low P availability, which is crucial for improving legume production and maintaining agricultural sustainability in the context of the global P crisis.
