Principles of Plant Breeding
TL;DR: The history of plant breeding can be traced back to the early days of agriculture as discussed by the authors, when the first plants were planted in the wild. But the main focus was on hybridization of plants and the consequences of hybridization.
Abstract: INTRODUCTORY TOPICS. Darwinian Evolution. Origins of Agriculture. Evolution During Domestication. Mating Systems of Plants. Overview of Plant Breeding. BIOLOGICAL FOUNDATIONS OF PLANT BREEDING. Heredity and Environment. Genetic Consequences of Hybridization. Inheritance of Continuously Varying Characters: Biometrical Genetics. Evolution During Cultivation. Marker-Assisted Analysis of Adaptedness in Nature. Marker-Assisted Dissection of Adaptedness in Cultivation. MODERN BREEDING PLANS. Reproductive Systems and Breeding Plans. Breeding Self-Pollinated Plants. Breeding Hybrid Varieties of Outcrossing Plants. Breeding Clonally Propagated Plants. Breeding Hybrid Varieties of Selfing Plants and Plants that Are Clonally Propagated in Nature. Plant Breeding for Low-Input Agricultures. Glossary. References. Index.
Citations
More filters
TL;DR: The evidence that the evolution of breeding systems of animals and plants has been significantly influenced by the occurrence of inbreeding depression is reviewed, and the contemporary genetic theory of inmarriage depression and heterosis and the experimental data concerning the strength of in breeding depression are considered.
Abstract: The harmful effects of close inbreeding have been noticed for many centuries (34, 35, 165). With the rise of Mendelian genetics, it was realized that the main genetic consequence of inbreeding is homozygosis (165, Ch. 2). Two main theories were early proposed to account for inbreeding depression and its converse, heterosis (the increase in vigor observed in an F1 between two inbred lines). These are the overdominance and partial dominance hypotheses, discussed in more detail below. Research into this question has continued up to the present, and this is one of the topics that we discuss. Darwin (35, 36) was the first to point out that the evident adaptations of many plants for ensuring outcrossing could be understood in terms of the selective advantage of avoiding inbreeding depression. We review the evidence that the evolution of breeding systems of animals and plants has been significantly influenced by the occurrence of inbreeding depression. In order to do this, we consider the contemporary genetic theory of inbreeding depression and heterosis, and the experimental data concerning the strength of inbreeding depression. We emphasize data and theory relevant to natural, rather than domesticated, populations as we are chiefly concerned to evaluate the evolutionary significance of inbreeding depression. We do not attempt to give a complete bibliography of this very extensive field but try to concentrate on what seem to be the most significant findings in relation to this aim.
3,135 citations
TL;DR: An overview of the advantages of MAS and its most widely used applications in plant breeding, providing examples from cereal crops and ways in which the potential of MAS can be realized are suggested.
Abstract: DNA markers have enormous potential to improve the efficiency and precision of conventional plant breeding via marker-assisted selection (MAS). The large number of quantitative trait loci (QTLs) mapping studies for diverse crops species have provided an abundance of DNA marker–trait associations. In this review, we present an overview of the advantages of MAS and its most widely used applications in plant breeding, providing examples from cereal crops. We also consider reasons why MAS has had only a small impact on plant breeding so far and suggest ways in which the potential of MAS can be realized. Finally, we discuss reasons why the greater adoption of MAS in the future is inevitable, although the extent of its use will depend on available resources, especially for orphan crops, and may be delayed in less-developed countries. Achieving a substantial impact on crop improvement by MAS represents the great challenge for agricultural scientists in the next few decades.
1,736 citations
TL;DR: RFLP linkage maps provide a more direct method for selecting desirable genes via their linkage to easily detectable RFLP markers and may make it possible to clone genes whose products are unknown, such as genes for disease resistance or stress tolerance.
Abstract: Breeders have traditionally improved plant varieties by selecting on the basis of phenotype. Now restriction fragment length polymorphism (RFLP) linkage maps are being constructed for most major crop plants and these maps provide a more direct method for selecting desirable genes via their linkage to easily detectable RFLP markers. The integration of RFLP techniques into plant breeding promises to: (1) Expedite the movement of desirable genes among varieties, (2) Allow the transfer of novel genes from related wild species, (3) Make possible the analysis of complex polygenic characters as ensembles of single Mendelian factors, and (4) Establish genetic relationships between sexually incompatible crop plants. In the future, high density RFLP maps may also make it possible to clone genes whose products are unknown, such as genes for disease resistance or stress tolerance.
1,239 citations
TL;DR: A unified presentation, a synthesis, and an evaluation of the methods employed in the estimation of heritability in plants are presented, discussing the use of both collateral and lineal relatives and the biases present in the estimators.
Abstract: A unified presentation, a synthesis, and an evaluation of the methods employed in the estimation of heritability in plants are presented. Asexual, cross‐fertilizing, and self‐fertilizing diploid species, as well as annual and perennial ones, are considered. All broad‐ and narrow‐sense heritabilities are defined on individual and family bases for prediction of response to selection for a target population of environments in space and time. Narrow‐sense heritabilities are defined in cross‐fertilizing species for expected response to variations of mass, half‐sib, and full‐sib family selection for the next generation and the long term, and similarly in self‐fertilizing species. The use of both collateral and lineal relatives to estimate heritability is discussed, and the biases present in the estimators are given. Many departures and variations of the common procedures are discussed. The standard errors of heritability estimators and confidence intervals are presented.
795 citations
TL;DR: Considerable improvements in salt tolerance of important crop species have been achieved in the past 2 decades using barley, rice, pearl millet, maize, sorghum, alfalfa, and many grass species, relying solely on assessment of the phenotypic expression of these species.
Abstract: Accumulation of high levels of salts in the soil is characteristic of arid and semi-arid regions. Although different curative and management measures are being used to render salt-affected soils fit for agriculture, they are extremely expensive and do not provide permanent solutions to overcome the salinity problem. In contrast, a biotic approach for overcoming salinity stress has gained considerable recognition within the past few decades in view of the vast experimental evidence from what has happened in nature concerning the evolution of highly salt-tolerant ecotypes of different plant species, and also from the remarkable achievements that have been made in improveing different agronomic traits through artificial selection. Considerable improvements in salt tolerance of important crop species have been achieved in the past 2 decades using barley, rice, pearl millet, maize, sorghum, alfalfa, and many grass species. Such achievements relied solely on assessment of the phenotypic expression of t...
743 citations