Author: Muhammad Shahid Masood Publisher: ISBN: Category : Winter wheat Languages : en Pages : 340
Book Description
A major factor limiting the efficiency of plant improvement programs is the lack of knowledge as to which parental combinations to make when working with quantitatively inherited traits. The primary objective of this study was to provide information regarding the use of combining ability analysis to predict which cross combinations would result in the greater frequency of desirable segregates. Five winter wheat parents were used to develop a 5x5 diallel cross. Over a two year period parents, Fl, F2, F3, and F4 generations involving top cross populations were evaluated. Information was collected on an individual plant basis for seven traits: plant height, tiller number, spike length, spikelets per spike, biological yield, grain yield, and harvest index. Griffing's (1956) model 1, method 2 was used to estimate GCA and SCA in Fl and later generations. Narrow-sense heritability estimates were computed using regression in standard units across generations. Significant GCA estimates were obtained for most traits in all generations with the exception of tiller number and grain yield in the Fl during 1986-87. Specific combining ability estimates were also found to be important for all traits, except spikelets per spike in the Fl and F3 generations. High GCA to SCA ratios indicated a preponderance of additive gene action. Exceptions to the trend were grain yield and tiller number in the Fl during 1986-87. Low GCA and narrow-sense heritability estimates suggest that selection for these two traits would have to be delayed until later generations. When considered over generations, both GCA and SCA estimates were found to be significant. Significant SCA over generations indicated the presence of additive x additive epistasis. The GCA effects contributed by a particular parent were consistent over all generations indicating that F2 and F3 generations can be used effectively for combining ability analysis. However, the results did suggest that GCA estimates were more influenced by the environment than SCA. For the traits measured and in the populations used in this study, GCA effects did predict the best parental combinations for obtaining the highest percentage of desirable progeny in segregating populations.
Author: Andy Clark Publisher: DIANE Publishing ISBN: 1437903797 Category : Technology & Engineering Languages : en Pages : 248
Book Description
Cover crops slow erosion, improve soil, smother weeds, enhance nutrient and moisture availability, help control many pests and bring a host of other benefits to your farm. At the same time, they can reduce costs, increase profits and even create new sources of income. You¿ll reap dividends on your cover crop investments for years, since their benefits accumulate over the long term. This book will help you find which ones are right for you. Captures farmer and other research results from the past ten years. The authors verified the info. from the 2nd ed., added new results and updated farmer profiles and research data, and added 2 chap. Includes maps and charts, detailed narratives about individual cover crop species, and chap. about aspects of cover cropping.
Author: William Larry Alexander Publisher: ISBN: Category : Wheat Languages : en Pages : 182
Book Description
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.
Author: Philippe Monneveux Publisher: Frontiers E-books ISBN: 2889191818 Category : Languages : en Pages : 238
Book Description
This topic is a unique attempt to simultaneously tackle theoretical and practical aspects in drought phenotyping, through both crop-specific and cross-cutting approaches. It is designed for – and will be of use to – practitioners and postgraduate students in plant science, who are grappling with the challenging task of evaluating germplasm performance under different water regimes. In Part I, different methodologies are presented for accurately characterising environmental conditions, implementing trials, and capturing and analysing the information this generates, regardless of the crop. Part II presents the state-of-art in research on adaptation to drought, and recommends specific protocols to measure different traits in major food crops (focusing on particular cereals, legumes and clonal crops). The topic is part of the CGIAR Generation Challenge Programme’s efforts to disseminate crop research information, tools and protocols, for improving characterisation of environments and phenotyping conditions. The goal is to enhance expertise in testing locations, and to stimulate the development and use of traits related to drought tolerance, as well as innovative protocols for crop characterisation and breeding.
Author: Helmut Lieth Publisher: Springer Science & Business Media ISBN: 9781402012020 Category : Science Languages : en Pages : 284
Book Description
This volume follows up a seminal meeting, presenting reports on progress made with recommendations made there. The text reports on the development of pilot projects and on the organization of an international organization. All this will serve as the foundation for future efforts to develop the common utilisation of cash crop halophytes.
Author: Food and Agriculture Organization of the United Nations Publisher: Food & Agriculture Org. ISBN: 9251345619 Category : Cooking Languages : en Pages : 420
Book Description
This publication provides an overview of the common and unique sustainability elements of Indigenous Peoples' food systems, in terms of natural resource management, access to the market, diet diversity, indigenous peoples’ governance systems, and links to traditional knowledge and indigenous languages. While enhancing the learning on Indigenous Peoples food systems, it will raise awareness on the need to enhance the protection of Indigenous Peoples' food systems as a source of livelihood for the 476 million indigenous inhabitants in the world, while contributing to the Zero Hunger Goal. In addition, the UN Decade of Action on Nutrition (2016-2025) and the UN Food Systems Summit call on the enhancement of sustainable food systems and on the importance of diversifying diets with nutritious foods, while broadening the existing food base and preserving biodiversity. This is a feature characteristic of Indigenous Peoples' food systems since hundreds of years, which can provide answers to the current debate on sustainable food systems and resilience.
Author: Delivering Alien Invasive Species Publisher: Springer Science & Business Media ISBN: 1402082800 Category : Science Languages : en Pages : 421
Book Description
Biological invasions by alien (non-native) species are widely recognized as a significant component of human-caused global environmental change and the second most important cause of biodiversity decline. Alien species threaten many European ecosystems and have serious environmental, economic and health impacts. The DAISIE (Delivering Alien Invasive Species Inventories for Europe) project has now brought together all available information on alien species in Europe (terrestrial, aquatic and marine) and from all taxa (fungi, plants, animals). Thus for the first time, an overview and assessment of biological invasions in the Pan-European region is finally possible. The Handbook of Alien Species in Europe summarises the major findings of this groundbreaking research and addresses the invasion trends, pathways, and both economic as well as ecological impact for eight major taxonomic groups. Approximately 11.000 alien species recorded in Europe are listed, and fact sheets for 100 of the most invasive alien species are included, each with a distribution map and colour illustration. The book is complemented by a regularly updated internet database providing free additional information. With its highly interdisciplinary approach, DAISIE and its Handbook will be the basis for future scientific investigations as well as management and control of alien invasive species in Europe.
Author: Muhammad Shahid Masood
Author: George Albert Berger
Author: Andy Clark
Author: William Larry Alexander
Author: 
Author: Philippe Monneveux
Author: Helmut Lieth
Author: Marianne Sarrantonio
Author: Food and Agriculture Organization of the United Nations 
Author: Delivering Alien Invasive Species