Genetic Analysis of Fertility Restoring Genes for the AL-type Cytoplasm Male Sterility in Wheat

Fertility restoration of wheat male sterile line with AL-type cytoplasm is one of the main factors affecting its application in breeding programs,and the study of its genetic mechanism is helpful to develop better restorer lines.The sterile lines CMS18A and its corresponding maintainer lines 18B were crossed with the restorer lines 99AR144-1,F1,F2 and three kinds of BC1 population aBC1(sterile line//sterile line/restorer line),bBC1(sterile line/restorer line//maintainer line) and cBC1(sterile line/restorer line//restorer line),were used to study the genetic behaviors of fertility restoring genes.The results showed that the fertility restoration of 99AR144-1 was controlled by two pairs of dominant nuclear genes.The ratios of fertile to sterile in the F2 populations from the cross of AL18A with 99AR144-1 were 15∶1 and the ratios in the aBC1 were 3∶1 by plant fertility segregation analysis,two pairs of restoring genes have superposition and accumulation effect.The results showed that the fertility segregation in the bBC1 populations deviated obviously from 3∶1,we preliminarily thought that the genetic of female gamete of restoring gene was abnormal under AL-type cytoplasm background.