Download or read book Vegetative Developments of Inbred and Hybrid Maize written by Morris Evans Paddick and published by . This book was released on 1944 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Vegetative Development of Inbred and Hybrid Maize written by M.E. Paddick and published by . This book was released on 1944 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Corn plants of the inbred strains La and Pr and the hybrid strains La x Pr x La were studied during germination, when the thirds, fifth, tenth and fifteenth leaves were unrolling, and at vegetative maturity. Studies were made by dissecting the plants and taking weights and linear measurements on various parts, particularly the leaves. Emphasis was placed on comparisons between inbreds and F1 hybrids as they passed through the sucessive stages of development. The following observations were made: The hybrids developed faster as shown by the speed with wich sucessive leaves and whorls of roots were initiated. Faster linear growth of seedling radicles on hybrid plants indicated greater meristematic activity. The hybrids made greater overall growth as indicated particularly by much larger immature leaves of comparable position on plants of the same age. Comparable plant parts at maturity were larger in the hybrids. In leaf blades this could be accounted for by greater maximum width and lenght at least equal to that of one of the parental lines for the first few leaves, and much greater for the later-formed leaves. Hybrid plants appeared to have excelled in extent of development and size of parts, having produced 20 to 22 leaves compared with 18 or 20 for the inbreds. The most striking difference between mature hybrid and mature inbred plants existed in leaves formed after the twelfth or thirteenth, which were much heavier, longer and wider on the hybrids. Since these leaves developed during the phase of tassel formation and rapid eulm elongation. It is possible that on the inbred plant they were subject to an inhibiting influence which was less effective on the hybrid plants or did not take effect so soon. From these studies hybrid vigor appears as a factor both accelerating the growth activities of the plant and earrying then on to a point beyond that common in less vigorous inbreds.

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 Epigenetics in Plants of Agronomic Importance Fundamentals and Applications written by Raúl Alvarez-Venegas and published by Springer. This book was released on 2014-07-22 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decades, chromatin remodelling has emerged as an important regulator of gene expression and plant defense. This book provides a detailed understanding of the epigenetic mechanisms involved in plants of agronomic importance. The information presented here is significant because it is expected to provide the knowledge needed to develop in the future treatments to manipulate and selectively activate/inhibit proteins and metabolic pathways to counter pathogens, to treat important diseases and to increase crop productivity. New approaches of this kind and the development of new technologies will certainly increase our knowledge of currently known post-translational modifications and facilitate the understanding of their roles in, for example, host-pathogen interactions and crop productivity. Furthermore, we provide important insight on how the plant epigenome changes in response to developmental or environmental stimuli, how chromatin modifications are established and maintained, to which degree they are used throughout the genome, and how chromatin modifications influence each another.

Download or read book Comparative Development of the Embryos of Inbred and Hybrid Maize written by Robert Samuel Fairchild and published by . This book was released on 1950 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Maize written by Jeff L. Bennetzen and published by Springer Science & Business Media. This book was released on 2009-01-16 with total page 785 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maize is one of the world’s highest value crops, with a multibillion dollar annual contribution to agriculture. The great adaptability and high yields available for maize as a food, feed and forage crop have led to its current production on over 140 million hectares worldwide, with acreage continuing to grow at the expense of other crops. In terms of tons of cereal grain produced worldwide, maize has been number one for many years. Moreover, maize is expanding its contribution to non-food uses, including as a major source of ethanol as a fuel additive or fuel alternative in the US. In addition, maize has been at the center of the transgenic plant controversy, serving as the first food crop with released transgenic varieties. By 2008, maize will have its genome sequence released, providing the sequence of the first average-size plant genome (the four plant genomes that are now sequenced come from unusually tiny genomes) and of the most complex genome sequenced from any organism. Among plant science researchers, maize has the second largest and most productive research community, trailing only the Arabidopsis community in scale and significance. At the applied research and commercial improvement levels, maize has no peers in agriculture, and consists of thousands of contributors worthwhile. A comprehensive book on the biology of maize has not been published. The "Handbook of Maize: the Genetics and Genomics" center on the past, present and future of maize as a model for plant science research and crop improvement. The books include brief, focused chapters from the foremost maize experts and feature a succinct collection of informative images representing the maize germplasm collection.

Download or read book Effects of Plant Densities on the Relationship Between Inbred and Hybrid Performance in Maize written by Veronica Machado-Correa and published by . This book was released on 1978 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Three Methods of Inbred Line Development in Two Maize Populations written by Gbadebo Olaoye and published by . This book was released on 1990 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Breeding for drought and nitrogen stress tolerance in maize From theory to practice written by M. Bänzinger and published by CIMMYT. This book was released on 2000 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction - why breed for drought and low N tolerance?; Conceptual framework - breeding; Conventional approaches to improving the drought and low N tolerance of maize; Conventional approaches challenged; The challenge of breeding for drought and low N tolerance; Maize under drought and low N stress; Conceptual framework - physiology; Water and the maize plant; Nitrogen and the maize plant; Maize under drought and low N stress - consequences for breeding; Stress management; Drought; Low N stress; Statistical designs and layout of experiments; Increasing the number of replicates; Improved statistical designs; Field layout; Border effects from alleys; Secondary traits; Why use secondary traits?; How do we decide on the value of secondary traits in a drought or low N breeding program?; Secondary traits that help to identify drought tolerance; Secondary traits that help to identify low N tolerance: Selection indices - Combining information on secondary traits with grain yield; Combining information from various experiments; Breeding strategies; Choice of germplasm; Breeding schemes; Biotechnology: potential and constraints for improving drought and low N tolerance; The role of the farmer in selection; What is farmer participatory research and why is it important?; What is new about farmer participatory research?; Participatory methodologies.

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 Barrenness and Plant to Plant Variability in Maize Zea Mays L written by Lin Li and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Vegetative Ontogeny and Lodging of Two Maize Inbreds and Their Hybrid written by Charles Milford Hall and published by . This book was released on 1951 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Cross and Self Fertilisation in the Vegetable Kingdom written by Charles Darwin and published by . This book was released on 1900 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experiment Station Record written by United States. Office of Experiment Stations and published by . This book was released on 1945 with total page 1052 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Flowering written by Abraham H. Halevy and published by CRC Press. This book was released on 2019-07-23 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: These volumes are an exhaustive source of information on the control and regulation of flowering. They present data on the factors controlling flower induction and how they may be affected by climate and chemical treatments. For each plant, specific information is provided on all aspects of flower development, including sex expression, requirements for flowering initiation and development, photoperiod, light density, vernalization, and other temperature effects and interactions. Individual species are described from the standpoint of juvenility and maturation, morphology, induction and morphogenesis to anthesis. All information is presented alphabetically for easy reference

Download or read book Experiment Station Record written by U.S. Office of Experiment Stations and published by . This book was released on 1947 with total page 1420 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hybrid Corn maize in Theory and Practice written by Gordon Haskell and published by . This book was released on 1949 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: