Abstract:

Twenty-nine large-stone, early-fruiting and fine quality nut-used varieties of Ginkgo biloba from China and Japan on fruiting characteristics through randomized block experiment(RBE) design at two experiment sites were studied.Twenty varieties fruited consecutively after grafted at high-position for 2～4 years, but difference of first fruiting time was very significant among varieties. Seeds of “cut-grafting" and “ring-grafting" trees distributed in inner crown. Young stage in G. biloba was longer, variation coefficients on fruit yield of twenty varieties were more than 50% in primary fruiting stage. The single stone weight(g),the percentage of stone weight to fruit weight and seed stone yield per cm² trunk cross section(kg) in “cut-grafting" trees were higher than those in “ring-grafting"trees. The results of Q-cluster analysis to six yield indices such as fruiting tree percentage, fresh fruit yield per tree(kg·tree^-1),stone yield per tree(kg·tree^-1),stone yield per trunk cross section area(kg·cm ^-2),stone yield per crown transmission area(kg·m^-2),and stone yield per planting area(kg·hm^-2)of twenty varieties showed that “HJW", “LN" and “T107#” belonged to high yield varieties. In this paper, biological characteristics of fruiting in G. biloba nut-used varieties were evaluated, which was very important to select large-stone, early-fruiting and high-yield G. biloba nut-used varieties.

Key words: Ginkgo biloba, nut-used variety, fruiting, cluster analysis