Abstract: Welsh onion ( A. fistulosum) buds of Cytoplasmic Male2Sterile (CMS) line and its maintainer line at differ2 ent developmental stages were employeded as experimental materials to reveal relationships between CMS and metabolisms of reactive oxygen species (ROS) by measuring productions of superoxide anion radical (O2 H ),content of malonadehyde (MDA) and activities of antioxidant enzymes ( superoxide,catalase and peroxidase enzymes). The result showed that at abortion preliminery stage,O2 H production rate of CMS buds increased singnificantly and reached the top at abortion peak stage,whereas content of MDA accumulated excessively from middle2bud stage to reach the top approximately at abortion peak stage. Simultaneously,both O2 H production rate and MDA content of CMS were higher significantly than those of its maintainer from the little2bud stage. Induced by O2 H productions,superoxide,catalase and peroxidase enzyme (SOD,CAT and POD) activities of CMS increased from abortion preliminery stage,however,SOD and CAT activities,which decreased continuously from the middle2bud stage,were lower than those of its maintainer at abortion peak stage. Compared with SOD and CAT,POD activity was lower than that of its maintainer before middle2bud stage,and then was higher signifi2 cantly,which resulted in scarcity of IAA of male2sterile buds.Accordingly,unbalanced O2 H metablisms,excessive accumulations of MDA and decline of protective enzymes′activities or change of some protective enzyme′s functions maybe the important reasons that cause CMS.

Key words: Welsh onion, Cytoplasmic male2sterile (CMS) line, Metabolisms of reactive oxygen species (ROS), Pro2 tective enzymes

CLC Number: 

• S633.03