Download or read book Heterosis and Combining Ability Estimates of Hybrids Involving Selected Restorer and Male Sterile Winter Wheats written by Charles Ray Glover and published by . This book was released on 1971 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimates of Heterosis for Five Agronomic Traits in Selected Winter X Spring and Winter X Winter Wheat Crosses Triticum Aestivum L Em Thell written by P. Brajcich and published by . This book was released on 1980 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concern regarding the lack of genetic variability and the apparent yield plateau reached in wheat breeding have prompted this investigation. The systematic crossing of spring and winter wheat types which have evolved to form somewhat different gene pools, may provide a source of additional usable genetic variability for future yield increases. Five winter and five spring wheat cultivars with different degrees of genetic similarities in their pedigrees were crossed to obtain F1's and F2's. The parents plus winter x spring F1's were planted in two growing seasons at Hyslop Agronomy Farm near Corvallis, Oregon. During the second season the winter x spring F2 and winter x winter F1 crosses were also included. Agronomic traits were measured on an individual plant basis. These traits were plant height, number of tillers per plant, 100 kernel weight, number of kernels per spike and grain yield. Analyses of variance were conducted for each trait. Estimates of the amount of usable genetic variation were determined by heterosis values, inbreeding depression and parent-progeny standard regressions. Possible interactions between years and the above five characters were determined for the winter x spring F1's. Evidence of non-additive gene action was found in the expression of heterosis and subsequent inbreeding depression which depended on the specific trait measured and the parents involved in the cross. The greatest heterosis values were noted for grain yield per plant. Crosses with the winter parent, Weique Red Mace, resulted in the highest estimates for grain yield. This was due to the late maturity of these hybrids and to the diverse genetic background of this winter parent compared to the five spring parents. Parent-progeny regressions indicated that a large amount of additive genetic variance was present for plant height, 100 kernel weight and grain yield an intermediate amount for kernels per spike and tillers per plant. Winter x spring F1 crosses resulted in higher heterosis estimates and a wider range of values between crosses than winter x winter F1 crosses. Parent-progeny regression estimates were similar in value for the two types of F1 populations. Thus, these results indicate that the systematic crossing between winter and spring wheats will produce greater total genetic variability for further wheat improvement. This is true for the development of hybrid wheat (non-additive) and may also be promising for conventional breeding programs when only the additive portion of the total genetic variance can be used. The data support the general conclusion that the amount of heterosis is a function of genetic diversity between the two parents. Those breeders working on hybrid wheat may wish to look at winter x spring crosses as a means of maximizing heterosis. However, since a significant interaction between years x F1's was noted for the traits measured, more than one year of evaluation will be necessary if winter x spring crosses are employed.
Download or read book Studies on Hybrid Vigor and Combining Ability in Wheat Diallel Crosses written by Daulat N. Sajnani and published by . This book was released on 1968 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genotype environment Interaction in Winter Wheat F1 Progeny written by Clarence James Peterson and published by . This book was released on 1970 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seven winter wheats were evaluated for plant height, the components of yield and yield in a diallel cross at Pendleton, Oregon and Lind, Washington. An additional parent was added to the diallel cross at Pullman, Washington. Two levels of nitrogen and five replications were utilized at each of the locations. Ten seeds of each F1 or parent were blended with 200 seeds of WA 4303 and seeded in a ten foot row. This was done in order to simulate a solid seeding with the limited amount of F1 seed. The data were analyzed by using Griffing's diallel analysis, Method 4, Model 1. The morphological traits measured were: heading date, kernels per spike, spikelets per spike, kernels per spikelet, weight per 1000 kernels, kernels per plant, spikes per plant and yield per plant. In an effort to obtain an unbiased combining ability estimate, a blend method of seeding (F1's mixed with a short semidwarf WA 4303) was used in order to simulate solid seedings. A comparison between the solid and blend seedings indicated, however, that WA 4303 did not exert the same influence on all hybrids. The estimate obtained should be less bias than those results obtained from other investigations where space or hill plantings were utilized. Significant general combining ability estimates were associated with all measured traits within the six environments, except for kernels per plant (high fertility) at one location. Specific combining ability estimates were significant for all traits at one location. Only part of the measured traits exhibited significant specific combining ability effects at the other two locations. Under the environments where specific combining ability estimates were significant they were larger than those for general combining ability for most traits. The lines utilized in this study were previously selected on the basis of their yielding ability. Therefore, the additive portion of the total genetic variance had already been maximized. The high specific combining ability estimates were attributed to this previous selection for additive gene action in addition to the nonadditive gene action which resulted from crossing of the selected lines. Heterosis and heterobeltiosis were exhibited by some hybrids for all measured traits and within all six environments. Heterosis and specific combining ability estimates were not always in close agreement which could result in some confusion in determining which crosses would perform best in a specific environment. These data would indicate that specific combining ability is a valid estimate of the total amount of nonadditive genetic variance present but in addition the additive genetic variance and the multiplicative action of the components are important and contribute to heterosis. The influence of the environmental-genotypic interaction as measured across locations was greater for specific combining ability estimates than that for the estimates of general combining ability for all traits measured. This suggests that the nonadditive genetic variance is more susceptible to changes in environmental conditions than is the additive portion of the total genetic variance.
Download or read book 2nd International Winter Wheat Conference written by and published by . This book was released on 1975 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Estimates of Heterosis and Combining Ability in Crosses Among Seven Hard Red Winter Wheat Varieties written by Young Woung Lee and published by . This book was released on 1969 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1973 with total page 1244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agronomy Abstracts written by and published by . This book was released on 1991 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes abstracts of the annual meetings of the American Society of Agronomy; Soil Science Society of America; Crop Science Society of America ( - of its Agronomic Education Division).
Download or read book Comprehensive Dissertation Index 1861 1972 Agriculture written by Xerox University Microfilms and published by . This book was released on 1973 with total page 1226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1973 with total page 624 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 1997 with total page 1504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Agriculture written by and published by . This book was released on 1976 with total page 1732 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acta Agronomica Academiae Scientiarum Hungaricae written by and published by . This book was released on 1966 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Doubled Haploid Production in Crop Plants written by M. Maluszynski and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: The production of doubled haploids has become a necessary tool in advanced plant breeding institutes and commercial companies for breeding many crop species. However, the development of new, more efficient and cheaper large scale production protocols has meant that doubled haploids are also recently being applied in less advanced breeding programmes. This Manual was prepared to stimulate the wider use of this technology for speeding and opening up new breeding possibilities for many crops including some woody tree species. Since the construction of genetic maps using molecular markers requires the development of segregating doubled haploid populations in numerous crop species, we hope that this Manual will also help molecular biologists in establishing such mapping populations. For many years, both the Food and Agriculture Organization of the United Nations (FAO) and the International Atomic Energy Agency (IAEA) have supported and coordinated research that focuses on development of more efficient doubled haploid production methods and their applications in breeding of new varieties and basic research through their Plant Breeding and Genetics Section of the Joint F AO/IAEA Division of Nuclear Techniques in Food and Agriculture. The first F AO/IAEA scientific network (Coordinated Research Programme - CRP) dealing with doubled haploids was initiated by the Plant Breeding and Genetics Section in 1986.
Download or read book National Agricultural Library Catalog written by National Agricultural Library (U.S.) and published by . This book was released on 1981 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agrindex written by and published by . This book was released on 1995 with total page 1006 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selection Methods in Plant Breeding written by Izak Bos and published by Springer Science & Business Media. This book was released on 2013-11-21 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our requirement for plant breeders to be successful has never been greater. However one views the forecasted numbers for future population growth we will need, in the immediate future, to be feeding, clothing and housing many more people than we do, inadequately, at present. Plant breeding represents the most valuable strategy in increasing our productivity in a way that is sustainable and environmentally sensitive. Plant breeding can rightly be considered as one of the oldest multidisciplin ary subjects that is known to humans. It was practised by people who first started to carry out a settled form of agriculture. The art, as it must have been at that stage, was applied without any formal underlying framework, but achieved dramatic results, as witnessed by the forms of cultivated plants we have today. We are now learning how to apply successfully the results of yet imperfect scientific knowledge. This knowledge is, however, rapidly develop ing, particularly in areas of tissue culture, biotechnology and molecular biology. Plant breeding's inherent multifaceted nature means that alongside obvious subject areas like genetics we also need to consider areas such as: statistics, physiology, plant pathology, entomology, biochemistry, weed science, quality, seed characteristics, reproductive biology, trial design, se lection and computing.
