State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China.
Council for Scientific and Industrial Research, Forestry Research Institute of Ghana, P. O. Box UP 63, KNUST, Fumesua, Kumasi, Ashanti Region, Ghana.
BMC Genom Data. 2023 Feb 15;24(1):8. doi: 10.1186/s12863-023-01107-8.
Rice is one of the most important food crops in the world and mainly cultivated in paddy field by transplanting seedlings. However, increasing water scarcity due to climate change, labor cost for transplanting, and competition from urbanization is making this traditional method of rice production unsustainable in the long term. In the present study, we mined favorable alleles for mesocotyl elongation length (MEL) by combining the phenotypic data of 543 rice accessions with genotypic data of 262 SSR markers through association mapping method.
Among the 543 rice accessions studied, we found 130 accessions could elongate mesocotyl length under dark germination condition. A marker-trait association analysis based on a mixed linear model revealed eleven SSR markers were associated with MEL trait with p-value less than 0.01. Among the 11 association loci, seven were novel. In total, 30 favorable marker alleles for MEL were mined, and RM265-140 bp showed the highest phenotypic effect value of 1.8 cm with Yuedao46 as the carrier accession. The long MEL group of rice accessions had higher seedling emergence rate than the short MEL group in the field. The correlation coefficient (r = 0.485**) between growth chamber condition (GCC) and field soil condition (FSC) showed positive relationship and highly significant (P < 0.01) indicating that the result obtained in GCC could basically represent that obtained under FSC.
Not every genotype of the rice possesses the ability to elongate its mesocotyl length under dark or deep sowing condition. Mesocotyl elongation length is a quantitative trait controlled by many gene loci, and can be improved by pyramiding favorable alleles dispersed at different loci in different germplasm into a single genotype.
水稻是世界上最重要的粮食作物之一，主要通过移栽秧苗在稻田中种植。然而，由于气候变化导致的水资源短缺、移栽劳动力成本以及城市化的竞争，这种传统的水稻生产方式在长期内变得不可持续。在本研究中，我们通过关联图谱分析方法，将 543 个水稻品种的表型数据与 262 个 SSR 标记的基因型数据相结合，挖掘出有利于中胚轴伸长长度（MEL）的有利等位基因。
在所研究的 543 个水稻品种中，我们发现 130 个品种在黑暗发芽条件下可以伸长中胚轴长度。基于混合线性模型的标记-性状关联分析显示，11 个 SSR 标记与 MEL 性状相关，p 值小于 0.01。在 11 个关联位点中，有 7 个是新的。总共挖掘出 30 个有利于 MEL 的有利标记等位基因，其中 RM265-140 bp 表现出最高的表型效应值 1.8cm，载体品种为粤稻 46。在田间，长中胚轴的水稻品种的出苗率高于短中胚轴的品种。生长室条件（GCC）和田间土壤条件（FSC）之间的相关系数（r=0.485**）呈正相关，高度显著（P<0.01），表明在 GCC 中获得的结果基本上可以代表在 FSC 中获得的结果。
并非每一个水稻基因型都具有在黑暗或深播条件下伸长中胚轴的能力。中胚轴伸长长度是一个由多个基因座控制的数量性状，可以通过将不同种质中分散在不同基因座的有利等位基因聚合到单个基因型中来提高。
