Download or read book Trait Variation and QTL Mapping in Early Season Maize Populations written by Raja Khanal and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Maize Genome written by Jeffrey Bennetzen and published by Springer. This book was released on 2018-11-24 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses advances in our understanding of the structure and function of the maize genome since publication of the original B73 reference genome in 2009, and the progress in translating this knowledge into basic biology and trait improvement. Maize is an extremely important crop, providing a large proportion of the world’s human caloric intake and animal feed, and serving as a model species for basic and applied research. The exceptionally high level of genetic diversity within maize presents opportunities and challenges in all aspects of maize genetics, from sequencing and genotyping to linking genotypes to phenotypes. Topics covered in this timely book range from (i) genome sequencing and genotyping techniques, (ii) genome features such as centromeres and epigenetic regulation, (iii) tools and resources available for trait genomics, to (iv) applications of allele mining and genomics-assisted breeding. This book is a valuable resource for researchers and students interested in maize genetics and genomics.
Download or read book Assessment of Diversity and Mapping of Quantitative Trait Loci in Sweet Corn written by James T. Gerdes and published by . This book was released on 1992 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic and QTL Analysis of Carotenoid Variation in Two Mapping Populations of Maize written by Robyn L. Stevens and published by . This book was released on 2007 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic Analysis of Quantitative Trait Loci with the Early Generations of an Elite Single cross Maize Population written by Dwi Asmono and published by . This book was released on 1998 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evidence of consistent detection was observed at 27% (25 of 93) of the QTLS. For grain yield and yield components, seventy-one QTLs were detected across samples, only thirteen were common in both samples. Chromosome 6 was significantly associated with grain yield in both samples. The magnitudes of QTL effects were not always consistent when QTLs were detected in a region for both samples. Most QTLs detected in both samples had the same parental effects.
Download or read book Quantitative Genetics in Maize Breeding written by Arnel R. Hallauer and published by Springer Science & Business Media. This book was released on 2010-09-28 with total page 669 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize is used in an endless list of products that are directly or indirectly related to human nutrition and food security. Maize is grown in producer farms, farmers depend on genetically improved cultivars, and maize breeders develop improved maize cultivars for farmers. Nikolai I. Vavilov defined plant breeding as plant evolution directed by man. Among crops, maize is one of the most successful examples for breeder-directed evolution. Maize is a cross-pollinated species with unique and separate male and female organs allowing techniques from both self and cross-pollinated crops to be utilized. As a consequence, a diverse set of breeding methods can be utilized for the development of various maize cultivar types for all economic conditions (e.g., improved populations, inbred lines, and their hybrids for different types of markets). Maize breeding is the science of maize cultivar development. Public investment in maize breeding from 1865 to 1996 was $3 billion (Crosbie et al., 2004) and the return on investment was $260 billion as a consequence of applied maize breeding, even without full understanding of the genetic basis of heterosis. The principles of quantitative genetics have been successfully applied by maize breeders worldwide to adapt and improve germplasm sources of cultivars for very simple traits (e.g. maize flowering) and very complex ones (e.g., grain yield). For instance, genomic efforts have isolated early-maturing genes and QTL for potential MAS but very simple and low cost phenotypic efforts have caused significant and fast genetic progress across genotypes moving elite tropical and late temperate maize northward with minimal investment. Quantitative genetics has allowed the integration of pre-breeding with cultivar development by characterizing populations genetically, adapting them to places never thought of (e.g., tropical to short-seasons), improving them by all sorts of intra- and inter-population recurrent selection methods, extracting lines with more probability of success, and exploiting inbreeding and heterosis. Quantitative genetics in maize breeding has improved the odds of developing outstanding maize cultivars from genetically broad based improved populations such as B73. The inbred-hybrid concept in maize was a public sector invention 100 years ago and it is still considered one of the greatest achievements in plant breeding. Maize hybrids grown by farmers today are still produced following this methodology and there is still no limit to genetic improvement when most genes are targeted in the breeding process. Heterotic effects are unique for each hybrid and exotic genetic materials (e.g., tropical, early maturing) carry useful alleles for complex traits not present in the B73 genome just sequenced while increasing the genetic diversity of U.S. hybrids. Breeding programs based on classical quantitative genetics and selection methods will be the basis for proving theoretical approaches on breeding plans based on molecular markers. Mating designs still offer large sample sizes when compared to QTL approaches and there is still a need to successful integration of these methods. There is a need to increase the genetic diversity of maize hybrids available in the market (e.g., there is a need to increase the number of early maturing testers in the northern U.S.). Public programs can still develop new and genetically diverse products not available in industry. However, public U.S. maize breeding programs have either been discontinued or are eroding because of decreasing state and federal funding toward basic science. Future significant genetic gains in maize are dependent on the incorporation of useful and unique genetic diversity not available in industry (e.g., NDSU EarlyGEM lines). The integration of pre-breeding methods with cultivar development should enhance future breeding efforts to maintain active public breeding programs not only adapting and improving genetically broad-based germplasm but also developing unique products and training the next generation of maize breeders producing research dissertations directly linked to breeding programs. This is especially important in areas where commercial hybrids are not locally bred. More than ever public and private institutions are encouraged to cooperate in order to share breeding rights, research goals, winter nurseries, managed stress environments, and latest technology for the benefit of producing the best possible hybrids for farmers with the least cost. We have the opportunity to link both classical and modern technology for the benefit of breeding in close cooperation with industry without the need for investing in academic labs and time (e.g., industry labs take a week vs months/years in academic labs for the same work). This volume, as part of the Handbook of Plant Breeding series, aims to increase awareness of the relative value and impact of maize breeding for food, feed, and fuel security. Without breeding programs continuously developing improved germplasm, no technology can develop improved cultivars. Quantitative Genetics in Maize Breeding presents principles and data that can be applied to maximize genetic improvement of germplasm and develop superior genotypes in different crops. The topics included should be of interest of graduate students and breeders conducting research not only on breeding and selection methods but also developing pure lines and hybrid cultivars in crop species. This volume is a unique and permanent contribution to breeders, geneticists, students, policy makers, and land-grant institutions still promoting quality research in applied plant breeding as opposed to promoting grant monies and indirect costs at any short-term cost. The book is dedicated to those who envision the development of the next generation of cultivars with less need of water and inputs, with better nutrition; and with higher percentages of exotic germplasm as well as those that pursue independent research goals before searching for funding. Scientists are encouraged to use all possible breeding methodologies available (e.g., transgenics, classical breeding, MAS, and all possible combinations could be used with specific sound long and short-term goals on mind) once germplasm is chosen making wise decisions with proven and scientifically sound technologies for assisting current breeding efforts depending on the particular trait under selection. Arnel R. Hallauer is C. F. Curtiss Distinguished Professor in Agriculture (Emeritus) at Iowa State University (ISU). Dr. Hallauer has led maize-breeding research for mid-season maturity at ISU since 1958. His work has had a worldwide impact on plant-breeding programs, industry, and students and was named a member of the National Academy of Sciences. Hallauer is a native of Kansas, USA. José B. Miranda Filho is full-professor in the Department of Genetics, Escola Superior de Agricultura Luiz de Queiroz - University of São Paulo located at Piracicaba, Brazil. His research interests have emphasized development of quantitative genetic theory and its application to maize breeding. Miranda Filho is native of Pirassununga, São Paulo, Brazil. M.J. Carena is professor of plant sciences at North Dakota State University (NDSU). Dr. Carena has led maize-breeding research for short-season maturity at NDSU since 1999. This program is currently one the of the few public U.S. programs left integrating pre-breeding with cultivar development and training in applied maize breeding. He teaches Quantitative Genetics and Crop Breeding Techniques at NDSU. Carena is a native of Buenos Aires, Argentina. http://www.ag.ndsu.nodak.edu/plantsci/faculty/Carena.htm
Download or read book Handbook of Maize Its Biology written by Jeff L. Bennetzen and published by Springer Science & Business Media. This book was released on 2008-12-25 with total page 593 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Maize: Its Biology centers on the past, present and future of maize as a model for plant science research and crop improvement. The book includes brief, focused chapters from the foremost maize experts and features a succinct collection of informative images representing the maize germplasm collection.
Download or read book Genetic Dissection of Yield Component Traits in Zea Mays Using Multiparent Advanced Generation Intercross Populations written by Kathryn Michel and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize (Zea mays L.) yield is a highly quantitative trait controlled by many loci of small effect, the environment, and genotype by environment interactions, which make it a difficult trait to study at the gene level. However, yield may be broken into components such as ear and kernel size and shape, which are more heritable than yield measured in small plots. Multiparent advanced generation intercross (MAGIC) populations and diversity panels are two types of populations that are useful for identifying quantitative trait loci (QTL) that influence phenotypes. This dissertation contains three research projects designed to investigate the control of quantitative traits impacting maize yield. First, we present the genomes of five founders of a Stiff Stalk MAGIC population. Between the reference inbred B73 and the other five inbreds, we found substantial genetic and genomic variation in addition to conservation of haplotypes from the base population from which the inbreds were selected. Second, we describe the Wisconsin-Stiff Stalk-MAGIC population, its associated resources, and demonstrate QTL mapping and genomic prediction for flowering time and plant height. Flowering time and plant height are important characteristics in hybrid maize breeding, so we measured them in both the per se population and two test-crossed hybrid populations. We found that QTL detection depended on the tester used, which was consistent with lower genomic predictive ability when training models with per se data to predict hybrid phenotypes. Third, we used a high throughput image analysis pipeline to measure yield components on four MAGIC populations and a diversity panel. We performed genetic mapping to identify candidate genes underlying ear and kernel size and shape. We found substantial overlap of our results across traits within and between populations and overlap with known metaQTL identified through previous studies. The results from these projects provide new insight into the genetic control of traits including flowering time, plant height, and the size and shape of ears and kernels, all of which impact overall maize yield.
Download or read book Fine mapping Major Domestication QTL on Chromosome Five in Zea Mays written by Alessandra Margaruite York and published by . This book was released on 2018 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize was domesticated from its wild ancestor, teosinte, approximately 9000 years ago and serves as an excellent model to study rapid evolution. This is because maize and teosinte provide an example of extreme morphological divergence in both its plant architecture and structure of its ears. Even with their drastic phenotypic differences, they are able to develop fully fertile offspring that allows us to study the genes responsible for the domestication process. To understand this process better, quantitative trait loci (QTL) mapping has been conducted to identify causal regions of the genome for many domestication traits. One major region of large effect is located on chromosome five. Specifically, many QTL associated with ear morphology are localized to this region. This work has aims to study this and has manifested into two different projects, both examining major domestication QTL identified on chromosome five. One investigates multiple ear size phenotypes co-localizing to the same region, while the other studies a known homolog for domestication of the nonshattering trait in other cereals. Both QTL had been previously identified in different maize-teosinte hybrid mapping populations and were excellent candidates for further study. Each project sheds light on a poorly understood region of the maize genome and the limitations of studying phenotypic traits with a complex genetic architecture. Together, this work demonstrates the complexity of the evolutionary process. In addition to this work, the final chapter highlights my interest in teaching and learning and delves into research that promotes diversity in STEM education by examining the effect of peer mentoring in a first-year STEM classroom.
Download or read book Mapping Quantitative Trait Loci in Outbred Half sib Populations written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantitative trait loci (QTL) mapping in outbred populations faces some challenges unique to the divergent genetic background and complex pedigree relationships. Motivated by a dairy cattle half-sib data set from a grand daughter design, we present in this dissertation a series of endeavors to address various challenges along the analysis flow of QTL mapping. A first step is to infer the haplotypes in sires based on the observed genotypes in sires and his offspring. Our method was shown to outperform peer methods with greater robustness and accuracy yet with fast speed performance. Then in light of adapting the multiple interval mapping method to within-family QTL analysis, we extended the modeling framework by allowing for heteroscedastic residual variances and upgraded the Windows QTL Cartographer accordingly. The advantageous post-analysis result parsing from Windows QTL Cartographer and more importantly, the improved analysis outputs due to more powerful maximum likelihood-based mixture modeling than the least squares regression manifest our efforts in delivering better methodology via practically user friendly software. We further developed a mixed model approach for the purpose of QTL mapping across multiple families that was aimed at modeling QTL effects as both the fixed effect across families and the random effect within families. Our mixed model was shown to encompass similar or higher statistical testing performance on QTL variation than the widely used variance component modeling approach, yet still allowing permutations for obtaining chromosome-wide or genome-wide significance threshold. What's more, the flexibility of our mixed model in constructing alternative hypotheses testing on either fixed or random QTL effects or both was shown to offer interesting insight into the varying sources of signal that would not be unveiled by least squares regression or variance component methods. In concluding our comprehensive approach to QTL linkage mapping in dair.
Download or read book Genetic Network Regulating Variation in Vegetative Phase Change in Maize written by Wei Zhang and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Vegetative phase change in maize is characterized by the transition from waxy juvenile leaves to pubescent, glossy adult leaves. In maize, mutants that alter the timing of vegetative phase change are valuable resources to identify the responsible factors. Also, continuous variation of leaf identity traits in diverse genetic mapping populations indicates the feasibility to use quantitative trait locus (QTL) analyses to find underlying genes. I demonstrate here that Glossy15 (Gl15) is the most important gene controlling leaf identity traits in maize. Decreased level of Gl15 mRNA in various gl15 mutant alleles promoted the transition from juvenile to adult leaf identity in all genetic backgrounds tested. Additionally, the Gl15 gene appears as the most significant QTL for leaf identity traits in multiple genetic mapping populations, where variation in both its DNA sequence and mRNA expression could explain phenotypic differences among population of diverse maize inbred lines. Building on studies of the genetic network controlling vegetative phase change in the model plant species Arabidopsis, microRNA156 (miR156) and its target the SQUAMOSA PROMOTER BINDIND LIKE PROTEIN (SPL) genes also control leaf identity traits in maize. The miR156g and SBP5 genes are found within other large-effect QTLs that controlling leaf identity traits, and the relative expression levels of these genes correlates with the timing of vegetative phase change. The unique and easily visible leaf identity traits in maize offer advantages to characterizing the effects of many other regulators as well. I found that the activities of GAs, an upstream component of the genetic network regulating vegetative phase change, promote adult leaf identity by influencing the antagonistic interactions of miR156 and miR172; whereas Gl15 conditions changes in epicuticular wax composition between juvenile and adult leaves by activating aldehyde reductase and suppressing aldehyde decarbonylase.
Download or read book Roots written by Jun J. Abe and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: The root is the organ that functions as the interface between the plant and the earth environment. Many human management practices involving crops, forests and natural vegetation also affect plant growth through the soil and roots. Understanding the morphology and function of roots from the cellular level to the level of the whole root system is required for both plant production and environmental protection. This book is at the forefront of plant root science (rhizology), catering to professional plant scientists and graduate students. It covers root development, stress physiology, ecology, and associations with microorganisms. The chapters are selected papers originally presented at the 6th Symposium of the International Society of Root Research, where plant biologists, ecologists, soil microbiologists, crop scientists, forestry scientists, and environmental scientists, among others, gathered to discuss current research results and to establish rhizology as a newly integrated research area.
Download or read book Quantitative Trait Loci written by Nicola J. Camp and published by Boom Koninklijke Uitgevers. This book was released on 2002-04-26 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Quantitative Trait Loci: Methods and Protocols, a panel of highly experienced statistical geneticists demonstrate in a step-by-step fashion how to successfully analyze quantitative trait data using a variety of methods and software for the detection and fine mapping of quantitative trait loci (QTL). Writing for the nonmathematician, these experts guide the investigator from the design stage of a project onwards, providing detailed explanations of how best to proceed with each specific analysis, to find and use appropriate software, and to interpret results. Worked examples, citations to key papers, and variations in method ease the way to understanding and successful studies. Among the cutting-edge techniques presented are QTDT methods, variance components methods, and the Markov Chain Monte Carlo method for joint linkage and segregation analysis.
Download or read book Molecular Plant Breeding written by Yunbi Xu and published by CABI. This book was released on 2010 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in plant genomics and molecular biology have revolutionized our understanding of plant genetics, providing new opportunities for more efficient and controllable plant breeding. Successful techniques require a solid understanding of the underlying molecular biology as well as experience in applied plant breeding. Bridging the gap between developments in biotechnology and its applications in plant improvement, Molecular Plant Breeding provides an integrative overview of issues from basic theories to their applications to crop improvement including molecular marker technology, gene mapping, genetic transformation, quantitative genetics, and breeding methodology.
Download or read book Meeting the challenges of global climate change and food security through innovative maize research Proceedings of the National Maize Workshop of Ethiopia 3 Addis Ababa Ethiopia 18 20 April 2011 written by and published by CIMMYT. This book was released on with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nutrient Use Efficiency from Basics to Advances written by Amitava Rakshit and published by Springer. This book was released on 2014-12-26 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses in detail multifaceted approaches to boosting nutrient use efficiency (NUE) that are modified by plant interactions with environmental variables and combine physiological, microbial, biotechnological and agronomic aspects. Conveying an in-depth understanding of the topic will spark the development of new cultivars and strains to induce NUE, coupled with best management practices that will immensely benefit agricultural systems, safeguarding their soil, water, and air quality. Written by recognized experts in the field, the book is intended to provide students, scientists and policymakers with essential insights into holistic approaches to NUE, as well as an overview of some successful case studies. In the present understanding of agriculture, NUE represents a question of process optimization in response to the increasing fragility of our natural resources base and threats to food grain security across the globe. Further improving nutrient use efficiency is a prerequisite to reducing production costs, expanding crop acreage into non-competitive marginal lands with low nutrient resources, and preventing environmental contamination. The nutrients most commonly limiting plant growth are N, P, K, S and micronutrients like Fe, Zn, B and Mo. NUE depends on the ability to efficiently take up the nutrient from the soil, but also on transport, storage, mobilization, usage within the plant and the environment. A number of approaches can help us to understand NUE as a whole. One involves adopting best crop management practices that take into account root-induced rhizosphere processes, which play a pivotal role in controlling nutrient dynamics in the soil-plant-atmosphere continuum. New technologies, from basic tools like leaf color charts to sophisticated sensor-based systems and laser land leveling, can reduce the dependency on laboratory assistance and manual labor. Another approach concerns the development of crop plants through genetic manipulations that allow them to take up and assimilate nutrients more efficiently, as well as identifying processes of plant responses to nutrient deficiency stress and exploring natural genetic variation. Though only recently introduced, the ability of microbial inoculants to induce NUE is gaining in importance, as the loss, immobilization, release and availability of nutrients are mediated by soil microbial processes.
Download or read book The Barley Genome written by Nils Stein and published by Springer. This book was released on 2018-08-18 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an overview of the state-of-the-art in barley genome analysis, covering all aspects of sequencing the genome and translating this important information into new knowledge in basic and applied crop plant biology and new tools for research and crop improvement. Unlimited access to a high-quality reference sequence is removing one of the major constraints in basic and applied research. This book summarizes the advanced knowledge of the composition of the barley genome, its genes and the much larger non-coding part of the genome, and how this information facilitates studying the specific characteristics of barley. One of the oldest domesticated crops, barley is the small grain cereal species that is best adapted to the highest altitudes and latitudes, and it exhibits the greatest tolerance to most abiotic stresses. With comprehensive access to the genome sequence, barley’s importance as a genetic model in comparative studies on crop species like wheat, rye, oats and even rice is likely to increase.
