Abstract：In order to explore the relationship between the structure and function of peroxidases,the changes of radish peroxidases(POD)activities were investigated at floral stage and the POD gene structure were also analyzed.Activities of POD in different organs of radish were determined.The expression profile of radish peroxidase genes(Rsprx)were analyzed by modified semi-quantitive RT-PCR,some partial cDNAs of radish peroxidase genes were cloned and sequenced.The results showed that the activities of POD were changed greatly in difterent organs at florescence in the Chinese red radish.POD activities were significantly difference between above-ground and under-ground organs.The peak of the POD activity was (17.53±0.35)×103 U•g-1 (FW)in xylemⅡ at producing legumen stage.The expression levels of the Rsprx were higher among different organs of Chinese red radish.There were significant differences in expression of Rsprx in bud and legumen.Four radish peroxidase partial cDNAs about 400 bp were cloned from the bud and legumen,which showed high identity and structure similarity with the flower-specific expressed cotton gene Ghpod by sequence alignment. There are correlation between POD and florescence growth and development of radish,and various peroxidases genes expression during the floral organ development processes of radish.
