Photoperiod-thermo-sensitive genic male sterile (PTGMS) rice exhibits a number of desirable traits for hybrid rice production. The cloning genes responsible for PTGMS and those elucidating male sterility mechanisms and reversibility to fertility would be of great significance to provide a foundation to develop new male sterile lines. Guangzhan63S, a PTGMS line, is one of the most widely used indica two-line hybrid rice breeding systems in China. In this study, genetic analysis based on F2 and BC1F2 populations derived from a cross between Guangzhan63S and 1587, determined a single recessive gene controls male sterility in Guangzhan63S. Molecular marker techniques combined with bulked-segregant analysis (BSA) were used and located the target gene (named ptgms2-1) between two SSR markers RM12521 and RM12823. Fine mapping of the ptgms2-1 locus was conducted with 45 new Insertion–Deletion (InDel) markers developed between the RM12521 and RM12823 region, using 634 sterile individuals from F2 and BC1F2 populations. Ptgms2-1 was further mapped to a 50.4 kb DNA fragment between two InDel markers, S2-40 and S2-44, with genetic distances of 0.08 and 0.16 cM, respectively, which cosegregated with S2-43 located on the AP004039 BAC clone. Ten genes were identified in this region based on annotation results from the RiceGAAS system. A nuclear ribonuclease Z gene was identified as the candidate for the ptgms2-1 gene. This result will facilitate cloning the ptgms2-1 gene. The tightly linked markers for the ptgms2-1 gene locus will further provide a useful tool for marker-assisted selection of this gene in rice breeding programs.
水稻光溫敏雄性不育基因在雜交水稻制種中顯示許多優(yōu)良的性狀。PTGMS和那些闡釋雄性不育機制，恢復(fù)育性的基因克隆為發(fā)展新的雄性不育系提供了基礎(chǔ)。如廣占63S，它在我國的兩系雜交育種是用途最廣的秈型光溫敏不育系。本文中我們利用廣占63S與1587兩親本，發(fā)展F2和BC2F2群體，通過遺傳分析，我們發(fā)現(xiàn)在廣占63S中存在一個單隱性基因控制其雄性不育。通過BSA混池分析，可將ptgms2-1定位在2號染色體上RM12521和RM12823兩個SSR標(biāo)記間。進一步發(fā)展了45個新的InDel標(biāo)記，及利用634株F2和BC1F2群體，將該基因定位在50.4kb的S2-40和S2-44兩InDel標(biāo)記間。遺傳距離分別為0.08cM和0.16cM,并且與AP004039的BAC上的S2-43共分離。RiceGAAS預(yù)測其中有10個基因。核糖體核酸酶Z基因被認(rèn)為是ptgms2-1的候選基因。該結(jié)果有利于克隆該基因且在分子育種提供了有利的工具。