Effects of Pollination of Some Stigmas in Kiwifruit Flowers on Seed Distribution and Fruit Quality

Abstract

Kiwifruit flowers have approximately 40 stigmas. Artificial pollination is essential for dioecious kiwifruit production. We investigated the effect of the pollination site on seed distribution, fruit size and quality. We found that seeds should be evenly distributed in the fruit to improve fruit shape and that seed number and total soluble solids (TSS) were not positively correlated. We also noted that seeds were distributed in a spreading manner away from pollinated stigma. This indicated that the stigma and carpel had a similar one-to-one like connection. However, the connection was not exact, and seeds were distributed not only in a particular carpel, but also slightly the outside the carpel. Seeds were distributed uniformly in the fruit even when pollination was limited to the two most distant stigmas, and the number of seeds increased when the number of pollinated stigmas increased. These results indicated that it was not necessary to pollinate all stigmas, but only several stigmas, in order to achieve larger fruit size.