水稻种子衰老相关基因定位

QTL Associated with Seed Aging in Rice

利用ZS97×MH6 3组合衍生的 16 0份重组自交系进行种子衰老遗传分析。每份自交系 3批种子 ,即在武汉室温条件下存放 3年的自然衰老种子 ,收获 3个月后的种子 ,收获 3个月后再经过高温、高湿加快衰老处理的种子 ,供 2 5℃条件下考查发芽率和发芽势来衡量种子衰老状况。复合区间作图方法进行了 2批衰老种子的发芽势与发芽率QTL定位。自然衰老的那批种子在第 3染色体定位 2个影响发芽率QTL ,加性效应作用方向相反 ,第 1染色体上定位 1个发芽势QTL ;加速衰老的那批种子 ,在第 9染色体上定位了 2个发芽率QTL ,加性效应作用方向相反 ,第 1和 8染色体上分别定位了 1个发芽势QTL。这些发芽率和发芽势QTL不存在紧密连锁和一因多效关系 ,表明水稻种子自然衰老和加速衰老的机制可能由不同的遗传因子控制。

recombinant inbred lines from our previous developed population from the cross between Zhenshan 97 and Minghui 63 were used for the genetic analysis of seed aging. Seed germination rate (GR) and seed germination energy (GE) were used as the indices to evaluate the seed aging status. Normal seeds, natural aged seeds and accelerated aged seeds were germinated in the same condition for data collection of GR and GE. For the natural aged seeds, two QTLs for GR were detected on chromosome 3, the genotype of Minghui 63 increased GR at one QTL, but decreased GR at the other QTL. One QTL for GP was identified on chromosome 1. For the accelerated aged seeds, two QTLs were detected on chromosome 9, the directions of additive effect at two QTLs were opposite. Two QTLs for GE were detected on chromosomes 1 and 8, respectively. Minghui 63 genotypes at the two QTLs increased GE. No QTL for GR and GE was common detected within any batch of aged seeds and between the two batches of aged seeds. The results showed that there would be two different sets of genes controlled seed natural aging and accelerated aging.