Download or read book Genotypic Variability and Combining Ability of Quality Protein Maize Inbred Lines Under Stress and Optimal Conditions written by Dagne Wegary Gissa and published by . This book was released on 2008 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phenotypic and Genotypic Characterization of White Maize Inbreds Hybrids and Synthetics Under Stress and Non stress Environments written by Dan Makumbi and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize is susceptible to biotic and abiotic stresses. The most important abiotic stresses in Africa are drought and low soil fertility. Aflatoxin contamination is a potential problem in areas facing drought and low soil fertility. Three studies were conducted to evaluate maize germplasm for tolerance to stress. In the first study, fifteen maize inbred lines crossed in a diallel were evaluated under drought, low N stress, and well-watered conditions at six locations in three countries to estimate general (GCA) and specific combining ability (SCA), investigate genotype x environment interaction, and estimate genetic diversity and its relationship with grain yield and heterosis. GCA effects were not significant for grain yield across environments. Lines with good GCA effect for grain yield were P501 and CML258 across stresses. Lines CML339, CML341, and SPLC7-F had good GCA effects for anthesis silking interval across stresses. Additive genetic effects were more important for grain yield under drought and well-watered conditions. Heterosis estimates were highest in stress environments. Clustering based on genetic distance calculated using marker data from AFLP, RFLP, and SSRs grouped lines according to origin. Genetic distance was positively correlated with grain yield and specific combining ability. In the second study, synthetic hybrids were evaluated at seven locations in three countries to estimate GCA and SCA effects under low N stress and optimal conditions and investigate genotype x environment interaction. GCA effects were significant for all traits across low N stress and optimal conditions. The highest yielding synthetic hybrids involved synthetics developed from stress tolerant lines. Synthetics 99SADVIA-# and SYNA00F2 had good GCA for grain yield across low N stress conditions. Heterosis was highly correlated with grain yield. Optimal environments explained more variation than stress environments. The third study evaluated the agronomic performance and aflatoxin accumulation of single and three-way cross white maize hybrids at five locations in Texas. Inbreds CML343, Tx601W, and Tx110 showed positive GCA effects for grain yield. Significant GCA effects for reduced aflatoxin concentration were observed in lines CML269, CML270, and CML78 across locations. Differences in performance between single and three-way crosses hybrids were dependent mostly on the inbred lines.

Download or read book GGE Biplot Analysis written by Weikai Yan and published by CRC Press. This book was released on 2002-08-28 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research data is expensive and precious, yet it is seldom fully utilized due to our ability of comprehension. Graphical display is desirable, if not absolutely necessary, for fully understanding large data sets with complex interconnectedness and interactions. The newly developed GGE biplot methodology is a superior approach to the graphical analys

Download or read book Combining Ability Analysis in Quality Protein Maize Inbred Lines written by Bullo Tulu and published by LAP Lambert Academic Publishing. This book was released on 2012-06 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Information on the combining ability of elite germplasm is essential to maximize their use for variety development. In the current study, sixty-six F1 crosses resulted from diallel crosses of 12 QPM inbred lines and two standard checks BHQP-542 and Melkassa-6Q were evaluated using alpha-lattice design with two replications during the 2009 cropping season at Mechara Agricultural Research Center. The objectives of the study were to determine general(GCA) and specific (SCA) combining ability for yield and yield related traits; estimate correlation among yield and yield related traits and find direct and indirect effects of yield related traits on grain yield. Analysis of variance showed that mean squares due to entries were significant to highly significant for most traits studied, indicating mean squares due to entries, crosses and crosses versus checks were non significant for stand count after thinning, leaf rolling, number of kernels per ear, plant aspect, shelling percentage, number of ears per plant and disease score. Entry and cross mean squares were non significant for stand count at harvest and ear aspect.

Download or read book Breeding Quality Protein Maize QPM written by and published by CIMMYT. This book was released on 2008 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Developing Drought and Low N tolerant Maize written by G. O. Edmeades and published by CIMMYT. This book was released on 1996 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Incidence and intensity of drought and low N stresss in the tropics; Case studies strategies for crop production under drought and low n stresses in the tropics; Stress physology and identification of secondary traits; Physiology of low nitrogen stress; Breeding for tolerance to drought and low n stresses; General breeding strategies for stress tolerance; Progress in breeding drought tolerance; Progress in breeding low nitrogen tolerance; Experimental design and software.

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 Genetics Physiology Proteomics of Quality Protein Maize Inbred Lines Under Drought and Heat Stress written by Cleopatra Nyaradzo Pfunde and published by . This book was released on 2016 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Stress written by Ismail M. M. Rahman and published by BoD – Books on Demand. This book was released on 2012-01-25 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plants experience water stress either when the water supply to their roots becomes limiting, or when the transpiration rate becomes intense. Water stress is primarily caused by a water deficit, such as a drought or high soil salinity. Each year, water stress on arable plants in different parts of the world disrupts agriculture and food supply with the final consequence: famine. Hence, the ability to withstand such stress is of immense economic importance. Plants try to adapt to the stress conditions with an array of biochemical and physiological interventions. This multi-authored edited compilation puts forth an all-inclusive picture on the mechanism and adaptation aspects of water stress. The prime objective of the book is to deliver a thoughtful mixture of viewpoints which will be useful to workers in all areas of plant sciences. We trust that the material covered in this book will be valuable in building strategies to counter water stress in plants.

Download or read book Genetic Diversity and Combining Ability of Selected Quality Protein Maize QPM Inbred Lines Adapted to the Highland Agro ecology of Ethiopia written by Demissew Abakemal Ababulgu and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Maize Stress Breeding and Genetics written by Saif ul Malook and published by LAP Lambert Academic Publishing. This book was released on 2014-11-01 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thirty inbreeding lines of Zea mays were screened in a glasshouse. Eight best performing lines were selected based on nine traits screened to cross with testers. The resulting F1 hybrids were screened in the field for their performance. Root and shoot length ratio, fresh shoot weight, dry root weight, and dry shoot weight were the most important traits to be used as criteria in selecting drought tolerance maize genotypes. Principal component analysis suggested that K55TMS, OH3A54, W187R, A556, WA3748, WM13RA and A545 performed the best under normal and drought conditions. High heritability and genetic advance was found for plant height, 100-grain weight, grain rows per plant and grain yield per plant, suggesting that selection of high yielding maize genotypes is possible through this approach. High specific combining ability of W64SP, A495, A509 and A50-2 suggested pre-screening of inbred lines that the inbred lines may be an efficient approach to develop higher yielding maize hybrids through heterosis breeding under drought.

Download or read book Combining Ability Analysis of Maize Inbred Lines and Genotype X Environment Interaction of Hybrids for Grain Yield and Maize Streak Virus Resistance written by Sheila Juma and published by . This book was released on 2018 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phenotypic and Genotypic Characterization of High Lysine Maize written by Sandeep Bhatnagar and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Quality Protein Maize (QPM) with the mutant gene opaque-2 (o2), has higherlysine and tryptophan content and hard endosperm which is less susceptible tomechanical and biological damage. Three experiments were conducted to characterize the phenotypic and genotypic characteristics of high lysine maize. In the first experiment two separate diallels including 7 white and 9 yellow QPM inbreds were evaluated in five southern USA environments to estimate the general (GCA) and specific combining abilities (SCA) for grain yield and to identify potential heterotic relationships among them. QPM hybrids yielded less than commercial checks. GCA effects across environments were non-significant for grain yield but highly significant for secondary traits. Best yielding hybrids resulted from crosses among inbreds from different programs(CIMMYT, Mexico; University of Natal, South Africa and TAMU, USA). In the second experiment testcrosses between QPM inbreds and Tx804, were evaluated for agronomic performance, aflatoxin resistance and quality. QPM inbreds in testcrosses have similarflowering dates, plant height, ear height and test weights but lower grain yield than normal checks. Population 69 inbreds and their testcrosses were least susceptible to aflatoxin. Aflatoxin in testcrosses was positively correlated with endosperm texture (0.67) and kernel integrity (0.60) but negatively correlated with grain yield ( -0.30) andsilking date ( -0.50). Tryptophan content was negatively correlated with endosperm modification. Amino acid levels of inbred lines were significantly correlated with those of hybrids, but with low predictive value. In the third experiment 92 high lysine maize inbreds with different origins [Stiff Stalk, Non Stiff Stalk, Pop 69, temperate (Tx802,Tx804, Tx806, B97, B104) and exotic subtropical lines (CML161, Do940y and Ko326y)]were haplotyped on a cM scale utilizing 43 mapped SSR markers to characterize genetic diversity on chromosome 7, estimate linkage disequilibrium around opaque-2 locus and determine the parental contribution in some inbreds. Dendrograms of genetic similarity showed clusters in agreement with the different origin of inbreds. A total of 200 alleles were detected with an average of 4.7 alleles/locus. Significant linkage disequilibrium was detected around opaque-2 locus. Parental contributions of haplotypes showed segmentsof chromosome 7 exclusively contributed by one or the other parent.

Download or read book Asian Regional Maize Workshop 8 New Technologies for the New Millennium written by and published by CIMMYT. This book was released on with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quality Protein Maize written by International Symposium on Quality Protein Maize. Proceedings and published by . This book was released on 1994 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tropical Maize written by R. L. Paliwal and published by Fao. This book was released on 2000 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize is an important crop and the demand for as both food and animal feed is expected to grow by 235 million tonnes between now and 2030. In many countries it will be difficult to increase the area under cultivation, so gains will have to come from increased productivity and intensification of the cropping system. This book looks at all aspects of tropical maize production from physiology, growing environments, pest and diseases, plant breeding and crop management and it is a substantial information resource necessary for the development of the crop.

Download or read book Maize In The Third World written by Christopher Dowswell and published by CRC Press. This book was released on 2019-04-01 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize is the world's most widely grown cereal and a dietary staple throughout the Third World, but its full potential has only begun to be tapped. This book thoroughly examines the biological and economic issues relevant to improving the productivity of maize in developing countries. The authors explore a wide range of practical problems, from maxi