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 Heterosis Inbreeding Depression and Combining Ability Estimates from Diallel Crosses in Hard Red Winter Wheat written by Young Woung Lee and published by . This book was released on 1973 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heterosis Combining Ability and Stability Parameters in Successive Generations of Diallel Crosses in Wheat Triticum Aestivum written by Amarjit Singh Khehra and published by . This book was released on 1968 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heterosis Combining Ability and Variance covariance Relationships in a Diallel Cross Among Six Common Wheat Varieties of Diverse Origin written by William Oliver McIlrath and published by . This book was released on 1967 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Genetics and Exploitation of Heterosis in Crops written by CIMMYT. and published by CIMMYT. This book was released on 1997 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Genetic Divergence Combining Ability and Heterosis for Yield And written by Dilruba Majumder and published by LAP Lambert Academic Publishing. This book was released on 2012-04 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment was carried out with genetic divergence of spring wheat and combining ability, heterosis and heritability for yield and yield contributing characters from a five parent- half diallel cross in F2 generation for genotypes of wheat. Genetic divergence was assessed through Mahalanobis' D2 -statistics and Principal Component Analysis (PCA). The genotypes were grouped into six clusters. The combining ability analysis studied in the diallel cross populations. General combining ability (GCA) and specific combining ability (SCA) mean squares in F2 generation was significant for all the characters. There was significant expression of non additive gene actions even in F2 generation, which indicates that epistatic components of non additive gene actions might have been involved. The crosses Sonora x Opata and SA-92 x Rawal had positive and significant SCA effects for grain yield. Maximum mid parent heterosis for grain yield was 39.97% in the cross Sonora x NK-5 which was much higher than mid parent heterosis for other yield contributing characters. Positive relation was observed between heterosis of the crosses with their corresponding SCA effects.

Download or read book Biometrical genetics written by Kenneth Mather and published by Springer. This book was released on 2013-11-11 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of continuous variation are basic to the theory of evolution and to the practice of plant and animal improvement. Yet the genetical study of continuous variation has lagged far behind that of discontinuous variation. The reason for this situation is basically methodological. Mendel gave us not merely his principles of heredity, but also a method of experiment by which these principles could be tested over a wider range of living species, and extended into the elaborate genetical theory of today. The power of this tool is well attested by the speed with which genetics has grown. In less than fifty years, it has not only developed a theoretical structure which is unique in the biological sciences, but has established a union with nuclear cytology so close that the two have become virtually a single science offering us a new approach to problems so diverse as those of evolution, development, disease, cellular chemistry and human welfare. Much of this progress would have been impossible and all would have been slower without the Mendelian method of recognizing and using unit differences in the genetic materials.

Download or read book Combining Ability and Gene Action Estimates and the Association of the Components of Yield in Winter Wheat Crosses written by Warren Ervind Kronstad and published by . This book was released on 1963 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: A diallel cross consisting of ten parents was grown on the Hyslop Agronomy Farm near Corvallis, Oregon, in order to obtain estimates of the gene action contributing to yield and its components in wheat. Gene action estimates were obtained by two methods of diallel analysis and from narrow sense heritability values calculated by parent-progeny regressions involving both parental and F[subscript 1] data. In addition, path-coefficient analysis was utilized to investigate the direct and indirect associations of five variables on yield. The morphological characters measured were: (1) total yield per plant, (2) weight per kernel, (3) number of kernels per spikelet, (4) number of spikelets per spike, (5) number of spikes per plant and, (6) plant height. A large portion of the total genetic variation associated with the yield components, weight per kernel, kernels per spikelet, spikelets per spike and spikes per plant was the result of additive gene action. When the five variables were considered in terms of their associations with yield it was observed that weight per kernel, number of kernels per spikelet and the number of spikelets per spike mainly exerted direct effects on yield. The number of spikes per plant had no direct effect, but an indirect effect on yield through the other variables. A similar indirect association was noted for plant height. The data obtained from the path-coefficient analysis indicated further that the number of kernels per spikelet had the greatest direct effect on yield. Results obtained with correlation coefficients suggested that a negative association exists between weight per kernel and kernels per spikelet. Also such a negative association was found between the number of spikes per plant with weight per kernel and kernels per spikelet. These results would suggest the possible existence of a biological limitation between several of the components of yield. The diallel cross analysis for general and specific combining ability gave similar estimates of gene action when they were compared to narrow sense heritability values. However, when the Jinks-Hayman method was compared with the other two methods of estimating gene action, several discrepancies were observed. This lack of agreement was possibly due to the inability of this experimental material to meet one or all of the genetic assumptions required by the Jinks-Hayman method. The results of this study indicate that a breeding program with emphasis on increases in yield which considers each of the components separately, or in combination of two or more would offer the most promise. By this procedure the breeder could take advantage of the large amount of additive genetic variance associated with each of the components and at the same time, take into consideration any biological limitations which may exist. In utilizing the information obtained in this study in such a breeding procedure the plant breeder would be able to better evaluate the methods for selecting the best parents to be hybridized and in selecting the best lines from hybrid progeny.

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 Studies of Heterosis and Combining Ability in Top and Diallel Crosses Among Primitive Foreign and Cultivated American Upland Cottons written by Thomas Gailand White and published by . This book was released on 1962 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Early Generation Testing in a Diallel Cross Involving Four Winter Wheat Cultivars Triticum Aestivum Vill Host written by Abderrazak Daaloul and published by . This book was released on 1972 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Factors which influence the effectiveness of making early generation selections within bulk populations were investigated. Material utilized included the parents, F1, and F2 through F5 bulk populations resulting from a diallel cross. Information concerning the response of two traits, plant height and grain yield, was obtained for these populations at three diverse experimental sites. Estimates of gene action were determined by calculating heterosis, inbreeding depression, narrow-sense heritability, and combining ability values. Results obtained suggested that selections for plant height could be effectively made as early as the F2 generation since this trait was largely controlled by additive gene action. Grain yield was found to be influenced significantly by non-additive gene action; however most populations were stabilized by the F3 generations where high yielding populations could be identified and effective selection practiced. Results from this study suggested that genotype x environment interaction could influence early generation selection by masking the additive genetic effects. Under very favorable growing conditions the non-additive gene action x environment interaction dominated the additive effects for grain yield and to a lesser degree plant height. However, under dry land conditions both non-additive and additive genetic effects were masked by the environment and could not be expressed fully for grain yield. It is evident that for simply inherited traits like plant height, selection in the F2 generation must be practiced under an environment where there is full expression for that trait, while selection for grain yield must be conducted under the same environments where the potential varieties are to be grown. The use of Average Combining Ability as an indirect method to evaluate the contribution of parents to performance of the progency was found to be valid by the predicted results obtained for the simply inherited trait plant height. This method could be used with some confidence to estimate contribution of parents for a complex trait like grain yield. Two parents were identified as the best combiners for grain yield. This confirms what was learned about them after fifteen years of actual experience indicating the importance of a technique whereby the breeder can determine in a very short period of time which parents to cross and then concentrate his efforts within the more promising segregating populations.

Download or read book Genetic Improvement of Vegetable Crops written by G. Kalloo and published by Newnes. This book was released on 2012-12-02 with total page 846 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genetic improvement has played a vital role in enhancing the yield potential of vegetable crops. There are numerous vegetable crops grown worldwide and variable degrees of research on genetics, breeding and biotechnology have been conducted on these crops. This book brings together the results of such research on crops grouped as alliums, crucifers, cucurbits, leaf crops, tropical underground and miscellaneous. Written by eminent specialists, each chapter concentrates on one crop and covers cytology, genetics, breeding objectives, germplasm resources, reproductive biology, selection breeding methods, heterosis and hybrid seed production, quality and processing attributes and technology. This unique collection will be of great value to students, scientists and vegetable breeders as it provides a reference guide on genetics, breeding and biotechnology of a wide range of vegetable crops.

Download or read book Advances in Molecular Breeding Toward Drought and Salt Tolerant Crops written by Matthew A. Jenks and published by Springer Science & Business Media. This book was released on 2009-05-07 with total page 819 pages. Available in PDF, EPUB and Kindle. Book excerpt: With near-comprehensive coverage of new advances in crop breeding for drought and salinity stress tolerance, this timely work seeks to integrate the most recent findings about key biological determinants of plant stress tolerance with modern crop improvement strategies. This volume is unique because is provides exceptionally wide coverage of current knowledge and expertise being applied in drought and salt tolerance research.

Download or read book Journal of Agricultural Research written by and published by . This book was released on 2005 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Studies on Heterosis and Combining Ability in Bread Wheat Involving Gigas Spike Genotypes as Testers written by Sudesh and published by . This book was released on 2000 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heterosis and Combining Ability Studies in Wheat written by V. R. Patil and published by . This book was released on 1992 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book written by and published by INIAP Archivo Historico. This book was released on with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: