International Rice Research Institute, National Road, Los Banos, Laguna, Philippines.
Bangladesh Rice Research Institute, Gazipur, 1701, Bangladesh.
Theor Appl Genet. 2019 Mar;132(3):647-667. doi: 10.1007/s00122-018-3266-4. Epub 2018 Dec 17.
New models for integration of major gene MAS with modern breeding approaches stand to greatly enhance the reliability and efficiency of breeding, facilitating the leveraging of traditional genetic diversity. Genetic diversity is well recognised as contributing essential variation to crop breeding processes, and marker-assisted selection is cited as the primary tool to bring this diversity into breeding programs without the associated genetic drag from otherwise poor-quality genomes of donor varieties. However, implementation of marker-assisted selection techniques remains a challenge in many breeding programs worldwide. Many factors contribute to this lack of adoption, such as uncertainty in how to integrate MAS with traditional breeding processes, lack of confidence in MAS as a tool, and the expense of the process. However, developments in genomics tools, locus validation techniques, and new models for how to utilise QTLs in breeding programs stand to address these issues. Marker-assisted forward breeding needs to be enabled through the identification of robust QTLs, the design of reliable marker systems to select for these QTLs, and the delivery of these QTLs into elite genomic backgrounds to enable their use without associated genetic drag. To enhance the adoption and effectiveness of MAS, rice is used as an example of how to integrate new developments and processes into a coherent, efficient strategy for utilising genetic variation. When processes are instituted to address these issues, new genes can be rolled out into a breeding program rapidly and completely with a minimum of expense.
新的主基因 MAS 与现代育种方法相结合的模型有望极大地提高育种的可靠性和效率，促进传统遗传多样性的利用。遗传多样性被认为是作物育种过程中必不可少的变异来源，而标记辅助选择被认为是将这种多样性引入育种计划的主要工具，而不会带来供体品种中较差基因组的遗传累赘。然而，在世界范围内的许多育种计划中，实施标记辅助选择技术仍然是一个挑战。许多因素导致这种缺乏采用，例如不确定如何将 MAS 与传统的育种过程相结合，对 MAS 作为工具的信心不足，以及该过程的费用。然而，基因组工具、基因座验证技术以及新的模型的发展，为如何在育种计划中利用 QTL 提供了新的思路，有望解决这些问题。通过鉴定稳健的 QTL、设计可靠的标记系统来选择这些 QTL 以及将这些 QTL 导入优秀的基因组背景中，使它们能够在没有相关遗传累赘的情况下使用，从而实现标记辅助正向育种。为了提高 MAS 的采用率和有效性，以水稻为例，介绍了如何将新的发展和过程整合到一个连贯、高效的利用遗传变异的策略中。当实施这些过程来解决这些问题时，可以以最小的代价快速、完全地将新基因引入到一个育种计划中。
