A maintainer line of 3-line hybrid rice commonly presents a certain genetic distance to a 2-line restorer line, but in many cases, 2-line restorer lines present defects upon recovery of the object cytoplasmic male sterile (CMS) line of the maintainer line, which impedes the utilization of their heterosis. Here, we report a strategy and an example of converting a maintainer into a photoperiod/temperature-sensitive genic male sterile (P/TGMS) line with an almost identical genetic background, thus maximizing the heterosis. Firstly, through treatment of maintainer line T98B with 60CO-γ irradiation, we identified the TGMS line T98S, which is sterile at higher temperatures and fertile at lower temperatures. Secondly, the T98S line was proven to be identical to T98B with regard to genetic background via an examination of 48 parental polymorphous SSR markers and exhibited excellent blossom traits similar to those of T98B, with an extensive forenoon flowering rate of 75.92% and a high exertion rate of 64.59%. Thirdly, in a combination test, three out of six hybrids from T98S crossed with 2-line restorer lines showed a yield increase of 6.70-15.69% for 2 consecutive years. These results demonstrated that the strategy can generate a new P/TGMS line with strong general combining ability (converted from a maintainer line), thus helping to increase the genetic diversity of male sterile heterotic groups.

中文翻译：

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将水稻CMS维持剂转化为对光或热敏感的遗传雄性不育系。

3系杂交水稻的维持系通常与2系恢复系存在一定的遗传距离，但在许多情况下，2系恢复系在恢复维持系的目标细胞质雄性不育（CMS）系时会出现缺陷。线，这阻碍了其杂种优势的利用。在这里，我们报告一个策略和一个示例，将维持者转换为具有几乎相同的遗传背景的光周期/温度敏感型雄性不育（P / TGMS）品系，从而使杂种优势最大化。首先，通过用60CO-γ辐射处理维持系T98B，我们确定了TGMS系T98S，该系在较高温度下是无菌的，在较低温度下是可育的。其次，通过检查48个亲本多态性SSR标记，证明T98S品系在遗传背景上与T98B相同，并且表现出与T98B相似的优良开花性状，广泛的前花开花率达75.92％，且活度高。 64.59％。第三，在组合试验中，来自T98S的6个杂种中有3个与2系恢复系杂交，连续2年的产量增加了6.70-15.69％。这些结果表明，该策略可以产生具有较强综合能力的新P / TGMS品系（由维持系转化而来），从而有助于增加雄性不育杂种群体的遗传多样性。在一项组合试验中，来自T98S的六个杂种中有三个杂种与2系恢复系杂交，连续两年增产6.70-15.69％。这些结果表明，该策略可以产生具有较强综合能力的新P / TGMS系（从维持系转化而来），从而有助于增加雄性不育杂种群体的遗传多样性。在一项组合试验中，来自T98S的六个杂种中有三个杂种与2系恢复系杂交，连续两年增产6.70-15.69％。这些结果表明，该策略可以产生具有较强综合能力的新P / TGMS品系（由维持系转化而来），从而有助于增加雄性不育杂种群体的遗传多样性。