International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, 502324, India.
ICAR-Indian Institute of Pulses Research (IIPR), Kanpur, 208024, India.
Theor Appl Genet. 2019 Mar;132(3):797-816. doi: 10.1007/s00122-018-3252-x. Epub 2018 Dec 17.
Efficiency of breeding programs of legume crops such as chickpea, pigeonpea and groundnut has been considerably improved over the past decade through deployment of modern genomic tools and technologies. For instance, next-generation sequencing technologies have facilitated availability of genome sequence assemblies, re-sequencing of several hundred lines, development of HapMaps, high-density genetic maps, a range of marker genotyping platforms and identification of markers associated with a number of agronomic traits in these legume crops. Although marker-assisted backcrossing and marker-assisted selection approaches have been used to develop superior lines in several cases, it is the need of the hour for continuous population improvement after every breeding cycle to accelerate genetic gain in the breeding programs. In this context, we propose a sequence-based breeding approach which includes use of independent or combination of parental selection, enhancing genetic diversity of breeding programs, forward breeding for early generation selection, and genomic selection using sequencing/genotyping technologies. Also, adoption of speed breeding technology by generating 4-6 generations per year will be contributing to accelerate genetic gain. While we see a huge potential of the sequence-based breeding to revolutionize crop improvement programs in these legumes, we anticipate several challenges especially associated with high-quality and precise phenotyping at affordable costs, data analysis and management related to improving breeding operation efficiency. Finally, integration of improved seed systems and better agronomic packages with the development of improved varieties by using sequence-based breeding will ensure higher genetic gains in farmers' fields.
在过去的十年中，通过部署现代基因组工具和技术，豆科作物（如鹰嘴豆、兵豆和落花生）的繁殖计划效率得到了极大提高。例如，下一代测序技术使得基因组序列组装、数百个品系的重测序、HapMap 的开发、高密度遗传图谱、一系列标记基因型平台以及鉴定与这些豆科作物许多农艺性状相关的标记成为可能。尽管在某些情况下，已经使用标记辅助回交和标记辅助选择方法来开发优良品系，但在每个繁殖周期后不断进行群体改良以加速繁殖计划中的遗传增益是当前的需要。在这种情况下，我们提出了一种基于序列的繁殖方法，该方法包括使用亲本选择的独立或组合、增强繁殖计划的遗传多样性、早期世代选择的正向繁殖，以及使用测序/基因型技术进行基因组选择。此外，通过每年产生 4-6 代来采用快速繁殖技术将有助于加速遗传增益。虽然我们看到基于序列的繁殖在这些豆类作物的作物改良计划中具有巨大的潜力，但我们预计会面临一些挑战，特别是与高成本、高质量和精确表型相关的问题，以及与提高繁殖操作效率相关的数据分析和管理。最后，通过使用基于序列的繁殖方法开发改良品种，结合改良的种子系统和更好的农艺方案，将确保在农民的田间获得更高的遗传增益。
