Kallugudi Jayanth, Singh Vikram Jeet, Vinod Kunnumal Kurungara, Krishnan Subbaiyan Gopala, Nandakumar Shekharappa, Dixit Brijesh Kumar, Ellur Ranjith Kumar, Bollinedi Haritha, Nagarajan Mariappan, Kumar Amit, Chakraborti Mridul, Seth Rakesh Kumar, Mondal Tapan Kumar, Bhowmick Prolay Kumar, Singh Ashok Kumar
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi 110012, India.
Rice Breeding and Genetic Research Centre, ICAR-Indian Agricultural Research Institute, Aduthurai 612101, India.
Plants (Basel). 2022 Jul 26;11(15):1930. doi: 10.3390/plants11151930.
The exploitation of heterosis through intersubspecific hybridisation between and has been a major breeding target in rice, but is marred by the cross incompatibility between the genomes. Wide compatibility (WC) is a triallelic system at the locus on chromosome 6 that ensures the specificity of hybridisation within and between and The allele that favours intercrossing is sparsely distributed in the rice gene pool and therefore warrants identification of diverse WC sources to develop superior intersubspecific hybrids. In this study, we have identified several novel WC sources through the marker-assisted screening of a large set of 950 rice genotypes. Seventeen percent of the genotypes carried , which fell into two subpopulations. The WC genotypes showed wide phenotypic and genotypic variability, including both and lines. Based on phenotypic performance, the WC varieties were grouped into three clusters. A subset of 41 WC varieties was used to develop 164 hybrids, of which WC/ hybrids showed relative superiority over WC/ hybrids. The multilocation evaluation of hybrids indicated that hybrids derived from WC varieties, such as IRG137, IRG143, OYR128, and IRGC10658, were higher yielding across all the three different locations. Most of the hybrids showed the stability of performance across locations. The identified diverse set of wide compatible varieties (WCVs) can be used in the development of intersubspecific hybrids and also for parental line development in hybrid rice breeding.
通过粳稻和籼稻种间杂交来利用杂种优势一直是水稻育种的主要目标，但基因组间的杂交不亲和性影响了这一目标的实现。广亲和性是位于第6号染色体上的广亲和基因座位上的一个三等位基因系统，它确保了粳稻和籼稻种内及种间杂交的特异性。有利于种间杂交的S5-n等位基因在水稻基因库中分布稀少，因此有必要鉴定不同的广亲和资源，以培育优良的种间杂交种。在本研究中，我们通过对950份水稻基因型的大规模标记辅助筛选，鉴定出了几种新的广亲和资源。17%的基因型携带S5-n，可分为两个亚群。广亲和基因型在表型和基因型上表现出广泛的变异性，包括粳稻和籼稻品系。根据表型表现，将广亲和品种分为三个聚类。选取41份广亲和品种用于配制164个杂交组合，其中粳稻/广亲和杂交种比籼稻/广亲和杂交种表现出相对优势。杂交种的多点评价表明，来源于IRG137、IRG143、OYR128和IRGC10658等广亲和品种的杂交种在所有三个不同地点的产量都较高。大多数杂交种在不同地点表现出性能稳定性。所鉴定的不同广亲和品种集可用于种间杂交种的培育，也可用于杂交水稻育种的亲本系培育。
