水稻长芒基因LA1(Long Awn 1)的遗传分析与基因定位

为研究水稻芒的遗传调控机制,本研究在‘日本晴’/‘93-11’染色体片段代换系群体中筛选出一个长芒材料‘CSSL14’,研究了其主要农艺性状和长芒的遗传方式,并对长芒基因LA1进行了基因定位。结果表明‘CSSL14’的芒长、芒着生率、分蘖数和单株产量与‘93-11’存在极显著(p<0.01)或显著(p<0.05)差异,分别为‘93-11’的2.98倍、2.82倍、0.68倍和0.76倍。遗传分析表明‘CSSL14’的长芒表型受一对半显性基因LA1控制。通过图位克隆的方法,将LA1定位在第4染色体长臂标记M3和M4之间12.14 kb的范围内,该定位区间内只有1个预测的候选基因Os04g0518800,与已知的野生稻长芒基因An-2/LABA1等位。本研究结果为进一步研究LA1的功能提供了参考。

Genetic Analysis and Gene Mapping of LA1(Long Awn 1)in Rice

A long awn line’CSSL14’was selected from a set of chromosome segment substitution lines derived from a cross between japonica variety’Nipponbare’as the donor and indica variety’93-11’as the recurrent parent.In this study,the main agronomic traits and inheritance of’CSSL14’were performed,as well as the LA1 gene was mapped.The results showed that’CSSL14’had significantly differences(p<0.05)or extremely significantly(p<0.01)with’93-11’in yield per plant,length of awn,awn ration,tiller number,the value for’CSSL14’were 2.98,2.82,0.68,and 0.76 of those for’93-11’respectively.Genetic analysis showed that the trait of long awn phenotype in’CSSL14’was controlled by a pair of semi-dominant nuclear genes(LA1),which was fine-mapped to a 12.14 region of chromosome 4 defined by molecular markers M3 and M4.The gene annotation indicated that there was only one putative gene Os04 g0518800 in this region,which was allelic to An-2/LABA1.The results provide a basis for further study of LA1 function.