International Crops Research Institute for the Semi-Arid Tropics Hyderabad, India.
Front Plant Sci. 2013 Aug 20;4:309. doi: 10.3389/fpls.2013.00309. eCollection 2013.
The narrow genetic base of cultivars coupled with low utilization of genetic resources are the major factors limiting grain legume production and productivity globally. Exploitation of new and diverse sources of variation is needed for the genetic enhancement of grain legumes. Wild relatives with enhanced levels of resistance/tolerance to multiple stresses provide important sources of genetic diversity for crop improvement. However, their exploitation for cultivar improvement is limited by cross-incompatibility barriers and linkage drags. Pre-breeding provides a unique opportunity, through the introgression of desirable genes from wild germplasm into genetic backgrounds readily used by the breeders with minimum linkage drag, to overcome this. Pre-breeding activities using promising landraces, wild relatives, and popular cultivars have been initiated at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) to develop new gene pools in chickpea, pigeonpea, and groundnut with a high frequency of useful genes, wider adaptability, and a broad genetic base. The availability of molecular markers will greatly assist in reducing linkage drags and increasing the efficiency of introgression in pre-breeding programs.
品种遗传基础狭窄，遗传资源利用率低，是全球豆类作物生产和生产力的主要限制因素。需要开发新的和多样化的变异来源，以提高豆类作物的遗传基础。具有增强的多种胁迫抗性/耐受性的野生近缘种为作物改良提供了重要的遗传多样性来源。然而，由于种间杂交不亲和性障碍和连锁累赘的限制，它们在品种改良中的利用受到限制。通过将野生种质中的有利基因导入到育种者易于利用的遗传背景中，进行预繁殖，可以最小化连锁累赘，从而克服这一障碍。国际半干旱热带作物研究所（ICRISAT）已经开展了利用有希望的地方品种、野生近缘种和流行品种的预繁殖活动，旨在开发小豆、羽扇豆和落花生的新基因库，这些基因库具有更高的有用基因频率、更广泛的适应性和更广泛的遗传基础。分子标记的可用性将极大地有助于减少连锁累赘，并提高预繁殖计划中基因导入的效率。
