Relationship between Floral Sex Differentiation and Polyamines in Chestnut
ZHANG Xin-sheng, CHEN Hu, YU Li-chen, FU You (Changli Institute of Pomology, Hebei Academy of Agriculture and Forestry Sciences, Changli 066600, China)
Changes of the endogenous polyamines contents during chestnut floral sex differentiation and influence of exogenous polyamines in floral sex differentiation were studied in this report. The results showed that during the period of physiological development in the process of male flowers differentiation, the content of endogenous putrescine (Put) and endogenous spermidine (Spd) in the buds on fruit branches were higher than that in the buds on nutrition branches. During the period of female flowers differentiation, the changes of contents of three endogenous polyamines were similar in the buds on fruit branches and the buds on nutrition branches. After dropping to the least before germinating, the content of endogenous Put increased to relatively higher level in the period of germination. After a little rising up, the content of endogenous Spd and spermine (Spm) increased to a higher level rapidly. During the period of male flowers and female flowers differentiation, changes of Spd content were the largest, Put the second, and Spm the smallest. The results of application of exogenous polyamines showed that exogenous Put significantly inhibited bud differentiation, especially female flowers differentiation, and exogenous Spd promoted female flowers differentiation.