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Performance Of Several Generations Of Winter Wheat Composite Crosses Populations With A Modern Cultivar For Grain Yield And Disease Resistance Under Organic Farming
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Book Synopsis Performance of Several Generations of Winter Wheat Composite Crosses Populations with a Modern Cultivar for Grain Yield and Disease Resistance Under Organic Farming by : B.G. Fufa
Download or read book Performance of Several Generations of Winter Wheat Composite Crosses Populations with a Modern Cultivar for Grain Yield and Disease Resistance Under Organic Farming written by B.G. Fufa and published by . This book was released on 2014 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Composite cross populations (CCPs) are being tested for their value in organic systems as they are expected to buffer against chan ging environments due to their inherent genetic diversity resulting in improved yield stability over the years. The experiment was conducted in an organic field of Wageningen University and Research center in 2013/2014. Seven winter wheat composite crossed populations and one pure line as a check were evaluated for yield potential, resistance to disease and aphid infestation in a randomized complete block design with three replications.
Book Synopsis Comparisons of Several Generations of Winter Wheat Composite Cross Populations with a Modern Cultivar Under Organic Farming by : M.M. Kassie
Download or read book Comparisons of Several Generations of Winter Wheat Composite Cross Populations with a Modern Cultivar Under Organic Farming written by M.M. Kassie and published by . This book was released on 2013 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study was conducted in the organic trial field of Wageningen University and Research Centre with the objective of assessing the potentials of composite cross populations of winter wheat with the pure line cultivars. Four different aged composite cross population, one CCP-extra population and one pure line winter wheat cultivar were evaluated using a randomized complete block design with three replications. There were much more observed differences between the genotypes at the vegetative stage and not for the grain yield.
Book Synopsis Evaluation of Parental Performance for Grain Yield in Two Populations of Wheat (Triticum Aestivum Vill., Host) by : Maximino Alcala de Stefano
Download or read book Evaluation of Parental Performance for Grain Yield in Two Populations of Wheat (Triticum Aestivum Vill., Host) written by Maximino Alcala de Stefano and published by . This book was released on 1973 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Six winter wheat cultivars were evaluated for their breeding value in transmitting superior genetic factors for grain yield to subsequent progeny. The cultivars were selected on the basis of their potential grain yield and divided into two populations. Population I was comprised of three cultivars which have been in commercial production for several years and are regarded as intermediate for grain yield. Population II was represented by three recently developed cultivars which have superior grain yielding potential. Each of the three parents within each population were crossed in a diallel manner Hence, the parents and subsequent F1, F2, and BC progeny made up the experimental populations. These populations were grown at two environmentally diverse sites within the state of Oregon. Morphological characters measured were: (1) tillers per plant; (2) kernels per spike; (3) plant height; (4) weight of 300 kernels; and (5) grain yield. To detect which parental combination had the greatest potential for transmitting superior performance to the subsequent progeny for the components of yield and grain yield, the following parameters were determined for both populations: (1) the amount and nature of the genetic variance associated with each population; (2) average combining ability of each parent within the populations; (3) estimates of heterosis and heterobeltiosis in the F1 and (4) the possible influence of the genotype-environmental interactions on the parameters measured. Also information concerning the desirability of using top crosses and double crosses rather than single crosses was obtained. In an effort to compare the relative performance between the populations, Pullman Selection 101, which is a good general combining winter wheat cultivar, was used as a tester for both populations. The values obtained in this investigation reflect the properties of the populations studied and should not be interpreted as applying to all wheat populations. Considerable genetic variability was found within both populations for the characters studied. This variability was largely due to genetic factors which were additive. Tillers per plant and grain yield were influenced by both additive and nonadditive genetic variance. The higher yielding parents in Population II were found to be higher in their average combining ability for kernels per spike and grain yield per plant whereas the lower yielding parents in Population I were higher for tiller number, weight of 300 kernels and plant height. Parental combinations identified as being promising, for grain yield in a conventional program, where nearly homozygous lines are desired, were also the same parental combinations which resulted in a maximum expression of heterobeltiosis and would be of most interest in a hybrid program. The desirability of using multiple crosses to maximize the number of favorable factors need further study inctuding additional parents and different combinations plus an evaluation of the performance of such crosses in later generations. In this investigation, the single crosses appeared to be the most promising; however, inbreeding depression due to segregation within top and double crosses influenced the values obtained. Also, the population sizes should be increased to measure the total potential of such crosses. Significant genotype-environmental interactions were observed between locations for plant height and weight of 300 kernels. The estimates obtained for average combining ability, heterosis and heterobeltiosis for the other characters measured also suggested that it will be necessary to identify the most promising hybrid combinations based on the performance of the parents at the specific location. To make the most rapid progress in developing high yielding cultivars in either conventional or hybrid programs, the wheat breeder needs to emphasize crosses between unrelated high yielding cultivars. However, the need to provide superior parental lines which include such factors as disease resistance, should be evaluated. The development of elite germ plasm by geneticists will be mandatory if plant breeders are to continue to improve grain yield.
Book Synopsis Plant Diseases and Their Management in Organic Agriculture by :
Download or read book Plant Diseases and Their Management in Organic Agriculture written by and published by American Phytopathological Society. This book was released on 2015 with total page 402 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 1990 with total page 1254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Performance of Five Winter Wheat Cultivars when Grown in Composite and Pure Stand Populations Under Different Environmental Stresses by : Erdogan Indelen
Download or read book Performance of Five Winter Wheat Cultivars when Grown in Composite and Pure Stand Populations Under Different Environmental Stresses written by Erdogan Indelen and published by . This book was released on 1975 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five genetically and morphologically different winter wheat cultivars, Hyslop (H), Yamhill (Y), Paha (P), Luke (L), and Sprague (5) were blended in all possible combinations. These composites plus the five pure stands were planted in the fall of 1973 at three environmentally diverse locations in Oregon: Hyslop Agronomy Farm, Corvallis; Central Oregon Experiment Station, Madras; and Sherman Experiment Station, Moro. A triple lattice design was selected be cause of the large number of treatments with five filler cultivars added to balance the experiment. Eight traits, yield per plot, number of plants per plot, number of tillers per plot, number of heads per plant, yield per plant, number of kernels per head, 1000 kernel weight and plant height, were measured for each treatment. General and relative competitive ability of the cultivars in composite combinations and yield of pure stands were determined and ranked for all locations. Specific competitive ability was determined for all composite treatments. General and specific competitive ability were defined as the grain yield of the component lines across all composite combinations and within single treatments, respectively. Relative competitive ability was defined as yield of the component lines versus its pure stand in composite combinations. The rank for general and relative competitive ability and yield of pure stands were Y>H>P>L>S, Y>P>H>L>S, and H>Y>L> S>P, respectively at Corvallis. Only Hyslop yielded significantly higher than the mean of five pure stands. However, Yamhill was superior for general and relative competitive ability at this location. The rank of the component lines for general and relative competitive ability was the same at Madras (P>Y>H>S>L). But the yield rank of pure stands was different (L>H>Y>P>S). Luke and the composites, H+L+S, H+L, and H+Y+P yielded significantly higher than the mean of the five pure stands. General and relative competitive ability of cultivars when grown at Moro was Y>H>P>L>S and H>Y>P>L>S, respectively. The rank for yield for pure stands was Y>H>L>P>S. Yamhill was superior for general competitive ability and as a pure stand. However, Hyslop was superior for relative competitive ability. Pure stand Yamhill, H+L and H+Y combinations yielded significantly higher than the mean of the five pure stands. The cultivars had the same rank for general competitive ability at Corvallis and Moro. Significant differences were not found between treatments for yield in a combined analysis of variance. Analysis of variance indicated that treatments responded the same for all traits across all locations. Paha was very susceptible (80 percent) to leaf rust (Puccinia recondita) at Corvallis in 1974. Hyslop was resistant with the other cultivars having a lower percentage of disease than Paha. The 15 composite combinations containing Paha had between 20 and 50 percent leaf rust. The yield of 14 out of 15 composite combinations exceeded that of pure stand Paha. The mean infection of the five pure stands was higher than the mean infection of those composite combinations containing Paha. Composites composed of lines with different sources of resistance to leaf rust reduced the overall amount of disease. Composite populations were superior under stress or medium stress conditions whereas varieties per se were superior under ideal growing conditions. However the performance of a cultivar under pure stand conditions in a given environment is not a direct measure of its yielding ability in a composite. Therefore it will be necessary to test various composite combinations in different locations for several years before recommending a specific composite for commercial production.
Book Synopsis Symposium on Breeding for Diversification by : Jelena Ba?anovi?-Šiši?
Download or read book Symposium on Breeding for Diversification written by Jelena Ba?anovi?-Šiši? and published by kassel university press GmbH. This book was released on 2018-02-26 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are very happy that in this symposium researchers from a multitude of countries around the world are coming together in order to discuss issues about breeding for intra- and inter-specific diversity as well for annuals as for perennials. THe submitted abstracts show that the activities are far wider than just the cereals that are covered by the EU directive and that there will be a need to expand the activities on the legal side.
Book Synopsis Broadening the Genetic Base of Crop Production by : H. David Cooper
Download or read book Broadening the Genetic Base of Crop Production written by H. David Cooper and published by . This book was released on 2001 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the previously neglected interface between the conservation of plant genetic resources and their utilization. Only through utilization can the potential value of conserved genetic resources be realized. However, as this book shows, much conserved germplasm has to be subjected to long-term pre-breeding and genetic enhancement before it can be used in plant breeding programs.The authors explore the rationale and approaches for such pre-breeding efforts as the basis for broadening the genetic bases of crop production. Examples from a range of major food crops are presented and issues analyzed by leading authorities from around the world.
Book Synopsis Inheritance and Association of Earliness and Grain Yield in Four Winter X Spring Wheat Crosses (Triticum Aestivum L. Em Thell.) by : Ahmet Ertug Firat
Download or read book Inheritance and Association of Earliness and Grain Yield in Four Winter X Spring Wheat Crosses (Triticum Aestivum L. Em Thell.) written by Ahmet Ertug Firat and published by . This book was released on 1977 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Parental and segregating populations derived from four winter x spring wheat crosses were investigated to obtain information concerning the inheritance and association of earliness, grain yield and yieldrelated traits. Feasibility of selecting in early generations for these characteristics was also evaluated. Four winter wheat cultivars (Hyslop, Yamhill, Bezostaia 1, and Sprague) and one spring wheat cultivar (Inia 66) were chosen on the basis of their relative maturity and contrasting agronomic characteristics. Parents, F1 s, F2' s, and reciprocal backcrosses to both parents were planted in the fall in a space-planted randomized complete block design. The two environmentally diverse locations selected were the Hyslop Agronomy Farm, Corvallis, Oregon (1000 mm of rainfall) and Sherman Experimental Station, Moro, Oregon (250 mm of rainfall). The effectiveness of early generation selection for the measured characteristics was evaluated by growing F3 lines identified as the earliest 1% and the highest yielding 1% of F2 individuals in each cross. These were grown along with the parents, F1s, BC1 s, BC2 s and F2' s under space-planted conditions at Hyslop Agronomy Farm. A study with the same populations was conducted by vernalizing and planting in the spring to gain further information on earliness. Analyses of variance were conducted for all characteristics measured. Frequency distributions for days to heading of F1, F2, backcross generations and parents were examined. From the data collected, estimates of F 1 -midparent deviations, degree of dominance, heritability in the narrow sense and genetic advance under selection were determined for each cross. The data were further analyzed by parent-progeny regression, correlation and path-coefficient analyses, polynomial and multiple regressions. Partially dominant major genes, varying in number between one to five depending on the particular cross, appeared to influence heading date. Modifying factors also seemed to affect the date of heading. The gene action involved in the inheritance of earliness was primarily additive indicating that selection for earliness would be effective as early as the F2 generation under both high and low rainfall conditions. Estimates of additive and nonadditive gene action suggested both were equally important in determining the yield components. Higher heritability estimates for the components of yield indicated that there was more genetic variability associated with the yield components than yield per se. Occurrence of additive genetic variation by location interaction implied that selection should be practiced simultaneously under different environments if wide adaptability of potential lines is desired. Since pronounced additive effect by year interactions occurred for the yield components, delayed selection for these traits may not be productive. Positive correlations were obtained between yield and the number of days to heading when all generations were combined. However, in the F2 generations, it appeared possible to select for the desired earliness with high yields as indicated by the low association between these two traits. The path-coefficient analyses suggested that tiller number had the highest direct effect on grain yield. However, because of a negative association between tiller number and kernel weight, selection pressures would have to be balanced between these two components. In most cases, linear relationships existed between grain yield and seven measured traits, respectively. The result of regression analyses also showed that grain yield may be described best as a linear function of its components.
Book Synopsis Evaluation of Early Generation Testing in a Diallel Cross Involving Four Winter Wheat Cultivars (Triticum Aestivum Vill., Host) by : Abderrazak Daaloul
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 Bibliography of Agriculture written by and published by . This book was released on 1976 with total page 1964 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1975- have "data provided by National Agricultural Library, U.S. Department of Agriculture."
Book Synopsis Wheat Landraces by : Nusret Zencirci
Download or read book Wheat Landraces written by Nusret Zencirci and published by Springer Nature. This book was released on 2021-09-15 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Landraces possess a very large genetic base in population structure and are dynamic populations of cultivated plants with historical origin, distinct identity, and without any formal crop improvement. They are often genetically diverse, locally adapted, and associated with traditional farming systems. Resistance genes to biotic and abiotic stress factors, which are especially diversified in landraces, are of great interest to plant breeders, faced with global climate challenge. In addition, gene pools made of different landraces grown in different ecological conditions can be used for wheat breeding to enhance quality; yield and other desirable agricultural parameters. An estimated 75% of the genetic diversity of crop plants was lost in the last century due to the replacement of high yielding modern varieties. There is, thus, an urgent need to preserve existing species, not only for posterity but also as a means to secure food supply for a rising world population. In this book, we provide an overview of wheat landraces with special attention to genetic diversities, conservation, and utilization.
Book Synopsis A Study of Methods of Parental Evaluation Using Testers to Predict Subsequent Progeny Performance in Winter Wheat (Triticum Aestivum L.) by : William Larry Alexander
Download or read book A Study of Methods of Parental Evaluation Using Testers to Predict Subsequent Progeny Performance in Winter Wheat (Triticum Aestivum L.) written by William Larry Alexander and published by . This book was released on 1980 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major objective of this study was to determine why certain winter wheat cultivars, when hybridized, will produce a greater proportion of desirable plants in subsequent, segregating generations. Three winter wheat parents were chosen as the experimental material, based on their known performance as parents. Yamhill and Pullman Selection 101 are recognized as cultivars with good combining abilities for grain yield. Crosses with Nugaines have been disappointing, even though the cultivar itself is high yielding. Each parent was crossed to a series of five testers. These testers were chosen on the basis of their genetic diversity, especially for the components of yield. This parent x tester crossing scheme was analyzed as a 3 x 5 factorial, where the main effects due to parents and testers were their general combining ability effect estimates. The interactions of these main effects were their specific combining abilities. F1 hybrids were evaluated for two years and F2 populations for one year to characterize the parents' capacity to transmit selected attributes to their resulting progeny. These generations were evaluated on a per plant basis for their grain yields and the primary components of yield, tillers per plant, kernels per spike, and 1000 kernel weight. The four methods of evaluating parents assessed were parental performance, midparent-progeny correlations, examination of individual crosses, and combining ability analysis. Midparent-progeny correlations usually were not significant within the progeny of each parent. Significant differences were not found for grain yields among the parents in either year. However, significant differences existed for their expressions of yield components. Parental expressions of the yield components were generally more erratic than those of their F1 progenies. Significant differences occurred for estimates of general combining ability effects in both years and for each generation in all traits. These estimates for a particular parent were relatively consistent. Specific combining ability was not found to be a dependable means of identifying superior combinations. Associations between the parental general combining ability effect estimates for kernels per spike and 1000 kernel weight were positive. Relationships between other yield component combinations were negative with regard to general combining ability effects. Trends observed in single crosses reflected the relative general combining abilities of the parents. Crosses involving Yamhill generally had fewer tillers with a higher number of kernels per spike, heavier kernel weights, and superior grain yields to those of the other parents. Progeny of Pullman Selection 101 were usually high in tillering, intermediate for number of kernels per spike, low in kernel weights, and intermediate for grain yields. The progeny of Nugaines were characterized by high tillering, a low number of kernels per spike, low kernel weights, and also low grain yields. The parent x tester crossing scheme was found to be an effective way of determining the potentials of the three parents by estimating their general combining abilities, as well as minimizing the number of crosses required. If, as found in this study, the general combining ability effect estimates of the parents for grain yield accurately predict performance of later generations, this parent x tester crossing scheme would be an efficient method of assessing the potentials of prospective parents in breeding programs.
Book Synopsis Evaluation of Three Methods of Selection in Relation to Yield and Yield Stability in Winter Wheat (Triticum Aestivum Vill., Host) by : Terd Charoenwatana
Download or read book Evaluation of Three Methods of Selection in Relation to Yield and Yield Stability in Winter Wheat (Triticum Aestivum Vill., Host) written by Terd Charoenwatana and published by . This book was released on 1971 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effectiveness of early generation selection for yield and yield stability and the possible identification of superior parental combinations were studied in winter wheat populations representing different levels of genetic diversity. Experimental material for evaluating yield stability consisted of nine bulk and seven modified bulk populations derived from nine parental combinations which represented the F, F9, and F10 generations. The F9 and F10 generations of nine bulk, nine modified bulk and two modified pedigree populations along with the respective parental populations were studied to determine the relationship of yield to genetic diversity. Linear regression of the mean yield of individual entries on the mean yield of all entries for each year was used to describe yield stability. Grain yield differences among populations and crosses were analyzed by a functional analysis of variance. The modified bulk populations were found to be superior to their respective parents in yield and to the bulk populations in yield and yield stability. The modified pedigree populations had the highest yield of all populations measured. It was concluded that populations with high genetic diversity not only do not produce the highest yield but may not provide the greatest stability of yield. Selection for grain yield in the F4 generation was effective in identifying superior segregates. It was also possible to develop populations which had more yield stability. The highest yielding progeny were obtained from crosses between the medium yielding parents rather than between the highest yielding parents. This suggested that parental performance was of limited value in predicting the yielding ability of their resulting progeny. Therefore, selection for suitable parental combinations could not be based on their individual performance in the present study. It appeared that genetic factors for adaptability are as important as the level of genetic diversity in determining yield stability. A breeding system that allows the breeder to identify and incorporate genetic factors for adaptability and still maintain some genetic diversity in a new variety is suggested. Such a breeding system would prolong the length of time a variety could remain in commercial production and would allow such a variety to be grown over a more extensive range of environments.
Book Synopsis Return to Resistance by : Raoul A. Robinson
Download or read book Return to Resistance written by Raoul A. Robinson and published by IDRC. This book was released on 1996 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the tradition of Silent Spring, Raoul Robinson's Return to Resistance calls for a revolution. Traditional plant breeding techniques have led us to depend more and more on chemical pesticides to protect ourcrops. Return to Resistance shows gardeners, farmers, and plant breeders how to use a long-neglected technique to create hardy new plant varieties that are naturally resistant to pests and disease. Horizontal resistance breeding has been largely ignored in this century due to the popularity and apparent successes of the Mendelian geneticists. However the colossal, unrecognized failure of m.
Book Synopsis Composite Cross Populations (CCPs) of Winter Wheat Under Low-input Farming Systems in the Netherlands by : Jinwook Kim
Download or read book Composite Cross Populations (CCPs) of Winter Wheat Under Low-input Farming Systems in the Netherlands written by Jinwook Kim and published by . This book was released on 2016 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Bulletin of the Atomic Scientists by :
Download or read book Bulletin of the Atomic Scientists written by and published by . This book was released on 1973-10 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.
