Pollen viability, stigma receptivity and fruiting characteristics of hazelnut

Changes of stigma length, pollen attachment to stigma, pollen germination characteristics on stigma and stigma receptivity after artificial pollination were studied using Corylus heterophylla and hybrid hazelnut(C.heterophylla×C.avellana) Dawei as the materials. The results showed that:1)pollen germination ratios of C.heterophylla and Dawei were 47.2% and 74.3% respectively on their own stigmas after the pollen was airdried and stored at 4℃ for 50 days. 2)The length of stigma attained peak value on the 5th day after anthesis under natural pollination conditions, then the stigma withered and shortened rapidly. Bagged stigma maintained the longest length within 30 days after anthesis. 3)Pollen attachment capability of Dawei stigma was stronger than that of C.heterophylla. Pollen grains attached on stigma reached the maximum on 4th day after anthesis under natural pollination conditions, and the pollen amounts of pollen grains of C.heterophylla and Dawei were 40.6 and 84.6 respectively, after that the amount of pollen grains reduced sharply; and after being bagged, the amounts were 58.1 and 78.5 on 30th day after anthesis. 4）Pollen tubes of C.heterophylla and Dawei could stretch to the end of stigma within 24 hours. 5)Receptive stigma percentages of C.heterophylla and Dawei were 87.3% and 92.1% respectively after stigma being bagged for 30 days. 6)Nonedible nut part of C.heterophylla was more than 50%, and blank nut was the major reason leading to nonedible nut. Nonedible nut part of Dawei was less than 15%. Flower drop ratio of the two hazelnut cultivars decreased by crosspollination, while crosspollination had no effects on nonedible nut ratio.