水稻矮秆突变体dtl1的分离鉴定及其突变基因的精细定位

文章通过对所构建的水稻突变体库进行大规模筛选,获得一个稳定遗传的矮秆突变体,与野生型日本晴相比,该突变体表现为植株矮化、叶片卷曲、分蘖减少和不育等性状,命名为dtl1(dwarf and twist leaf 1)。dtl1属于nl型矮秆,激素检测表明,矮秆性状与赤霉素和油菜素内酯无关。遗传分析显示,突变性状受单一隐性核基因控制。利用dtl1与籼稻品种Taichung Native 1杂交构建F2群体,将该突变基因DTL1定位于水稻第10染色体长臂2个SSR标记RM25923和RM6673之间约70.4 kb区域内,并与InDel标记Z10-29共分离,在该区域预测有13个候选基因,但未见调控水稻株高相关基因的报道,因此,认为DTL1基因是一个新的控制水稻株高的基因。

Characterisation of a rice dwarf and twist leaf 1(dtl1) mutant and fine mapping of DTL1 gene

Plant height is one of the most important agronomic traits,which determines grain yield.By a largescale screening of our mutant population,we identified a dwarf with twisty leaf mutant(dwarf and twist leaf 1,dtl1).Besides dwarf with twisty leaf,dtl1 also showed reduced tiller number and sterile phenotypes.Based on the internode length of dtl1,this mutant belongs to the nl type of dwarfing phenotype.Physiological assay with two phytohormones,gibberellin(GA),and brassinosteroid(BR),suggested that dtl1 was neither deficient nor insensitive to GA and BR.Genetic analysis showed that the phenotype of dtl1 was controlled by a single recessive gene.Using F2 population derived from a cross between dtl1 and an indica cultivar Taichung Native 1,the DTL1 gene was narrowed down to a 70.4 kb between two SSR markers,RM25923 and RM6673,on the long arm of chromosome 10,and co-segregated with InDel marker Z10-29,where thirteen open reading frames were predicted without known gene involved in controlling plant height.Thus,the DTL1 gene might be a novel gene which is related to plant height in rice.