以淡绿叶为标记的籼型光—温敏核不育系M2S的选育

Breeding of a Photo-thermoperiod Sensitive Genie Male Sterile indica Rice with a Pale-green-leaf Marker

以淡绿叶标记基因系ＩＧＭ１９与籼型光－温敏核不育系８９０２５杂交，再用８９０２Ｓ回交１次，通过多代选育获得了带淡绿色叶隐性标记性状，且育性转换特性与８９０２Ｓ明显不同的籼型光－温敏核不育系Ｍ２Ｓ。在杭州（３０°０５’Ｎ）自然条件下，Ｍ２Ｓ具有连续３０ｄ以上的不育期（不育度＞９９．５％），在秋季正常情况下，结实率可达５１．８％。人工气候箱控制条件下，Ｍ２Ｓ在短日适温时结实正常，在长日（１５．０ｈ）与所有处理温度（３０．１℃、２４．１℃和２３．１℃）、高温（３０．１℃）与所有处理日长（１５．０ｈ、１４．０ｈ和１２．５ｈ）的光温组合下均完全不育或高度不育。结实率的方差分析结果表明，其育性转换的温度效应和光周期效应均不显著，仅光温工作效应显著，属典型的光温互作雄性不育系。Ｍ２Ｓ本身较稳定的不育性和带有隐性淡绿色叶的标记性状将有利于在两系法杂交水稻中应用。

Incorporating recessive marker gene controlling pale-green-leaf(pgl)into a photo-thermoperiod sensitive genic male sterile indica rice (PGMS) 8902S by backcrossing,a PGMS indica rice with pale-green-leaf marker(i.e.M2S)was developed.The fertility response of M2S to photoperiod and temperature is different from that of 8902S. In the natural condition of Hangzhou (30°25'N),M2S was characterized with high male sterility(more than 99.5 %)over 30 days in summer and normal fertility during middle fall.The further analysis of M2S in phytotrons with 3 photoperiod(P)×3 temperature(T)treatments showed that M2S had absolute or high male sterility under long day (15. 0 h) with all temperature(30.1℃,24.1℃, 23.1℃)combinations and high temperature(30.1℃)with all photoperiod(15.0 h,14.0 h,12.5 h)combinations,but normal spikelet fertility under short day(12.5 h)favorite temperature (23.1￣24.1℃),and that the male sterility of M2S is controlled by P ×T interaction.This kind of stable male sterility in long day or/and high temperature,with combination of its palegreen-leaf marker for pseudo-hybrid detection at seedling stage,will make it advantageous to other existing indica PGMS in the hybrid seed production by two-line method when abnormal summer low temperature occurs.