Abstract:

Growth of pollen tube and style physiology characteristic index after pollination were studied for Self-compatible apple cultivar ‘Zaohongxiang' and self-incompatible apple cultivars ‘Dounan', ‘Fuji', ‘Golden Delicious'. The results showed that: pollen tube grew normally and entered into the style base after self-pollination of self-compatible cultivar and cross-pollination of self-incompatible cultivar. Self-pollination pollen tube of self-incompatible cultivars grew normally after self-pollination within 24 h and stopped growing after 48～72 h when the pollen tube reached the 1/2 of the style to stigma. The style SOD, POD and CAT activities of self-compatible cultivar ‘Zaohongxiang' were relatively stable within 48 h after self-pollination. The SOD, POD, CAT activities and MDA content of self-incompatible cultivars had great changes after self-pollination 24～72 h when the pollen tube stopped growing. Style GA3 content of self-compatible cultivar ‘Zaohongxiang' had a peak and the ABA decreased in 24 h after self-pollination. Style ABA content of self-incompatible cultivars increased significantly after self-pollination 12～48 h. The（IAA+GA3）/ABA ratio sharply increased at 12～24 h after self-pollination and then decreased in ‘Zaohongxiang', but it still was higher than that of self-in compatible cultivars.

Key words: Apple, self-incompatibility, style, enzyme, hormone