Preliminary Study on the Relationship Between Polyamine and Ethylene During Panicle Development in Cytoplasmic Male Sterile Rice

By using HPLC and GC, polyamines(Put, Spd and Spm) contents and ethylene release rate(ERR) were measured in the panicles of CMS line and its maintainer line of rice. The effects of MGBG, an inhibitor of biosynthesis of Spd and Spm, and AVG, an inhibitor of ACC biosynthesis, on PA content and ERR in the panicles and the fertility of pollen in the two lines were studied,too. The results showed that ERR in the panicles of CMS line was higher than in its maintainer line.Treatment with AVG decreased ERR in the panicles of both lines, and restored partly pollen fertility in CMS line. PA content in the panicles of CMS line was lower than these in those of its maintainer line. Treatment with MGBG decreased Spd and Spm levels in both lines,and pollen fertility in maintainer line. AVG inhibited ethylene production and promoted PA synthesis. MGBG inhibited PA synthesis and promoted ethylene production. Moreover, ethylene production was negatively correlated with the content of Spd+Spm in the panicles of both lines. It is shown that PA(Spd and Spm) and ethylene biosynthesis pathways compete for SAM during the development of panicle of CMS line and its maintainer line in rice.