Jiangxi Academy of Agricultural Sciences, Nanchang, 330200, People's Republic of China.
Sci Rep. 2023 Feb 10;13(1):2428. doi: 10.1038/s41598-023-29514-y.
Seed aging is the key factor leading to the loss of genetic integrity. In this study, the seeds of Dongxiang wild rice, Xianggu, 9194 and Nipponbare were kept in a plant incubator with constant temperature and humidity for artificial aging treatment. The genetic integrity of germplasm resources with different germination gradients were analyzed using 44 SSR markers. The results suggested that different accessions could be ranked in order of aging resistance from highest to lowest as common wild rice > Xianggu > 9194 > Nipponbare. In order to maintain the genetic diversity of rice, the population size for reproduction and regeneration should be between 60 and 140. After aging, the number of polymorphic alleles, the number of specific single plant, the ratio of polymorphic bands, the number of alleles, the number of effective alleles, gene diversity index and Shannon index of different accessions all decreased with the decrease of germination rate. The germination rate of 60% was the critical value to maintain genetic integrity. Besides, the genetic integrity of eighteen SSR markers was rapidly lost or significantly increased. The regions of these markers were closely related to seed viability or genetic integrity. This study provides a theoretical basis for determining the population size for reproduction and regeneration and the critical value of germination rate of rice resources.
种子老化是导致遗传完整性丧失的关键因素。在这项研究中，东乡野生稻、香桂、9194 和日本晴的种子在恒温恒湿的植物培养箱中进行人工老化处理。利用 44 个 SSR 标记分析了具有不同发芽梯度的种质资源的遗传完整性。结果表明，不同的材料可以按照抗老化能力从高到低的顺序排列，即普通野生稻>香桂>9194>日本晴。为了保持水稻的遗传多样性，繁殖和再生的种群大小应在 60 到 140 之间。老化后，不同材料的多态性等位基因数、特异单株数、多态带比、等位基因数、有效等位基因数、基因多样性指数和香农指数均随发芽率的降低而降低。60%的发芽率是维持遗传完整性的临界值。此外，18 个 SSR 标记的遗传完整性迅速丧失或显著增加。这些标记的区域与种子活力或遗传完整性密切相关。本研究为确定水稻资源的繁殖和再生种群大小以及发芽率的临界值提供了理论依据。
