Download or read book Comparisons Among Maize Hybrids Made from Unselected Lines Developed by Selfing and Full sibbing written by Eleuterio Lopez-Perez and published by . This book was released on 1977 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison Among Amize Hybrid Made from Unselected Lines Developed by Selfing and Full sibbing written by E. Lopez-Perez and published by . This book was released on 1977 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of the increasing trend to the production of single crosses, rather than double crosses or three-way crosses of corn, plant breeders are trying to select out, bydifferent methods, more productive inbred lines that preform better in single-cross hybrids. Two different methods of inbreeding (selfing and full-sibbing) were used to develop unselected inbred lines to produce single-, three-way-, and double-cross hybrids. F2 generations were produced from most of these hybrids. Hybrids were produced from lines at two differnt levels of inbreeding (50 and almost 100% homozygosity). Lines with F = 50% were obtainded fater one generation of selfing (S1) while the lines with as inbreeding coefficient F = 99.6% were obtaindec after eight generations of continuousselfing (S8). It was necessary to conduct three generations of full-sibbing to obtain lines with F + 50% and ten generations of fuu-sibbing plus three generations of selfing to obtain lines nearly homozygous (FS10S3, F = 98.6%). All the hybrids (12), some of their F2's (8), and five check varieties were grown in five locations (Kanawha, Ames, Agronomy Researcg Center; Ames, Hinds Farm, Ankehy, and Martinsburg) in 1976. For each location the following traits were recorded: stand, kernel depth, second ears per entry, ear height, ear length, ear diameter, cob diameter, cob diameter, 300-kernel weight, and yield. Each experimental included three replications. A series of orthogonal comparisons were developed for all these traits combined across the five (...).
Download or read book Inbreeding Depression in Iowa Stiff Stalk Synthetic Zea Mays L by Selfing and Full sibbing written by Ronald Lee Good and published by . This book was released on 1976 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inbreeding in maize (Zea mays L.) las been primarily by selfing because of its rapidity in developing inbred lines. Alternative methods have been considered for the development ofmore vigorous inbred lines, but limited data have been reported. We developed approximately 245 unselected lines from BSSSCO by each of three methods of inbreeding; selfing (S), full-sibbing (FS), and full-sibbing for five generations followed by selfing (FSS). Unselected lines were developed from BSSS(R)C6 byeach of two methods of inbreeding: 105 lines by selfing (S), and 73 by full-sibbing (FS). Data were collected for 12 traits: date of silk, plant and ear height, ear length, ear and cob diameter, kernel depth, yield, 300-kernel weight, stand, second ears per plant, and average barrenness per plant. The study was conducted for two years with four environments in 1974 and five in 1975. A least squares regression analysis was used which forced the regression lines of the inbreeding series from a particular cycle through a common origin. Execpt date of silk, all traits showed a linear trend with an increase in homozygosity in the BSSSCO. There were quadratic effects for plant height, ear length, ear diameter, kernel depth, and average barrenness per plant. Date of silk and second ears per plant did not show a linear trend with an increase in homozygosity in the BSSS(R)C6. There was a significant difference in inbreding depression among the three inbreeding series from the BSSSCO forplant height, cob diameter, yield, 300-kernel weight (...).
Download or read book Iowa State Journal of Research written by and published by . This book was released on 1978 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Forage Research written by and published by . This book was released on 1997 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Iowa State Journal of Research written by Iowa. State College, Cedar Falls and published by . This book was released on 1977 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inbreeding Depression as a Measure of Improvement in Alfalfa Medicago Sativa L written by Mohamed A. El-Nahrawy and published by . This book was released on 1987 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Journal of the Iowa Academy of Science written by and published by . This book was released on 1994 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plant Breeding Abstracts written by and published by . This book was released on 1977 with total page 1298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetics Abstracts written by and published by . This book was released on 1978 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cereals written by Marcelo J. Carena and published by Springer Science & Business Media. This book was released on 2009-04-21 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agriculture depends on improved cultivars, and cultivars are developed through proper plant breeding. Unfortunately, applied plant breeding programs that are focused on cereal commodity crops are under serious erosion because of lack of funding. This loss of public support affects breeding continuity, objectivity, and, perhaps equally important, the training of future plant breeders and the utilization and improvement of plant genetic resources currently available. Breeding programs should focus not only on short-term research goals but also on long-term genetic improvement of germplasm. The research products of breeding programs are important not only for food security but also for commodity-oriented public and private programs, especially in the fringes of crop production. Breeding strategies used for long-term selection are often neglected but the reality is that long-term research is needed for the success of short-term products. An excellent example is that genetically broad-based public germplasm has significantly been utilized and recycled by industry, producing billions of dollars for industry and farmers before intellectual property rights were available. Successful examples of breeding continuity have served the sustainable cereal crop production that we currently have. The fact that farmers rely on public and private breeding institutions for solving long-term challenges should influence policy makers to reverse this trend of reduced funding. Joint cooperation between industry and public institutions would be a good example to follow. The objective of this volume is to increase the utilization of useful genetic resources and increase awareness of the relative value and impact of plant breeding and biotechnology. That should lead to a more sustainable crop production and ultimately food security. Applied plant breeding will continue to be the foundation to which molecular markers are applied. Focusing useful molecular techniques on the right traits will build a strong linkage between genomics and plant breeding and lead to new and better cultivars. Therefore, more than ever there is a need for better communication and cooperation among scientists in the plant breeding and biotechnology areas. We have an opportunity to greatly enhance agricultural production by applying the results of this research to meet the growing demands for food security and environmental conservation. Ensuring strong applied plant breeding programs with successful application of molecular markers will be essential in ensuring such sustainable use of plant genetic resources.
Download or read book Agronomy News written by and published by . This book was released on 1978 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sept.-Oct. issue includes list of theses and dissertations for U.S. and Canadian graduate degrees granted in crop science, soil science, and agronomic science during the previous academic year.
Download or read book Maize for Biological Research written by William F. Sheridan and published by . This book was released on 1982 with total page 456 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 Plant Breeding and Farmer Participation written by Salvatore Ceccarelli and published by Food & Agriculture Org. This book was released on 2009 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book complements the traditional approach to plant breeding by addressing a number of issues specifically related to the participation of farmers in a plant breeding programme, and provides a comprehensive description and assessment of the use of participatory plant breeding in developing countries. It is aimed at plant breeders, social scientists, students and practitioners interested in learning more about its use, with the hope that they all will find a common ground to discuss ways in which plant breeding can be beneficial to all and can contribute to alleviate poverty.
Download or read book Red Clover Science written by N.L. Taylor and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the literature on red clover since about 1985. In each of the 17 chapters, an effort was made to summarize the earlier literature and to integrate the recent findings into this background. The timing is appropriate with the present interest in sustainable agriculture, in which red clover was so prominent in the past. This is the first book to be published which deals solely with this important forage species. Audience: Primarily scientists and scientifically trained technicians who will appreciate an up-to-date summary on red clover.
Download or read book A Guide to Sorghum Breeding written by Leland R. House and published by . This book was released on 1982 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
