The Relationship between Male Sterile Occurrence and Dynamics of Endogenous Hormone Contents during Flower Bud Development in CMS7311 of Heading Chinese Cabbage

To reveal the relationship between the occurrence of male sterility of CMS7311 and endogenous hormone levels. In this research,enzyme-linked immunosorbent assay( ELISA) method was used to compares the dynamics of endogenous hormone contents of the flower buds between male sterile and fertile plants in heading Chinese cabbage. The results showed that the content of endogenous hormones IAA,ABA,GA3,ZR and JA were significant different dynamics both in sterile plants and fertile plants during the flower bud development. Using the flower bud with the size of 2. 0- 2. 9 mm as the turning point,the IAA contents of prior stages in the sterile bud were less than that of the fertile bud,and were contrary at the later stages. With the same turning point,the declining dynamics of ABA contents showed an opening Vglyph which declining fast at the earlier stages and slow in the late sta-ges,this was just different from the trends in fertile plants. The dynamics of GA3 contents both in the sterile and fertile flower buds were all declining and then rising,the difference was that the dynamic range of GA3 content in sterile buds showed smaller and the GA3 content were always lower than that in fertile plants. The dynamics of JA contents in the sterile flower buds showed the violent change of decline,rise and decline,and was always higher than that in fertile buds. In the initial stage of male sterile occurring,ABA and JA were increased by 12. 47% and16. 18%,while the IAA,ZR and GA3 decreased by 14. 00%,23. 04% and 45. 68% than that in male fertile buds.IAA / ABA ratio showed a fluctuating dynamics which downward after the first rise in both flower buds. The difference was that IAA / ABA ratio in the bud early stage of male sterile plants was less than that in fertile plants,The rest three ratio,including IAA / GA3,IAA/ZR and ABA/GA3,showed the declining dynamics,and the ratios of IAA/GA3 and ABA / GA3 in male sterile plants were significantly higher than that in fertile plants. For the male sterility mainly occurred at the early stages of flower buds in CMS of heading Chinese cabbage,we concluded that the lack of GA3 which resulted into the unbablance of each endogenous hormone,may be associated with the occurrence of male sterility in CMS7311.