Development of practical photoperiod-sensitive cytoplasmic male sterility lines for hybrid wheat breeding

利用粗厚山羊草（Aegilops crassa）细胞质在长日照条件下产生的光敏细胞质雄性不育（PCMS），建立了一种新的普通小麦（Triticum aestivum）杂交种选育方法。PCMS系在短日照条件下通过自花授粉保持，并且可以通过PCMS系与授粉者在长日照条件下的异交产生杂交种子。本研究的目的是为杂交小麦育种提供实用的核不育系。2002年，利用2001年杂交的野林26的FI杂交种，选育出不含Rf基因的优良品系：中国143、福留、中国131、筑后泉。2003年，对农林26 /藤见子和这4个优良品系的BC 1系进行了调查，筛选出农林26 /藤见子/2^* 中国143和农林26 /藤见子/2^* Fukuotome等10个短日照条件下自交结实率高、杂交结实率高的PCMS系。2004年，在野林26 /藤见小木/3^* Fukuotome的BC 2系中，筛选出两个在短日照条件下种子育性高、在长日照条件下雄性不育性高的实用PCMS系。

A two-line system using photoperiod-sensitive cytoplasmic male sterility (PCMS) caused by Aegilops crassa cytoplasm under a long-day photoperiod (≧15 h) has been proposed as a new means of producing hybrid varieties in common wheat (Triticum aestivum). The PCMS line is maintained by self-pollination under short-day conditions, and hybrid seeds can be produced through outcrossing of the PCMS line with a pollinator under long-day conditions. The objective of this research is to develop practical PCMS lines for hybrid wheat breeding. In 2002, using FI hybrid of Norin 26 crossed in 2001, we selected four elite lines, Chugoku 143, Fukuotome, Chugoku 131, Chikugoizumi, which has no Rf gene. In 2003, BC1 lines of Norin 26 / Fujimikomugi and these four elite lines were investigated and 10 lines of Norin 26 / Fujimikomugi /2^* Chugoku 143 and Norin 26 / Fujimikomugi /2^* Fukuotome were screened as PCMS lines with high selfed seed fertility and high crossed seed fertility under short-day condition. In 2004, among BC2 lines of Norin 26 / Fujimikomugi /3^* Fukuotome, two lines were screened as practical PCMS lines with high seed fertility under short-day condition and high male sterility under long-day condition.