Pollination and Erratic Bearing in ‘Italian’ Prune1

Abstract

Erratic fruitfulness, reputedly characteristic of ‘Italian’ prune in many areas, was pronounced in this 2-year study. Supplemental pollination with self-pollen and with pollen of 2 other cultivars did not increase fruit set over that of open-pollination in any orchard regardless of whether yield was high or low. Controlled self- and cross-pollinations established that ‘Italian’ is self-fertile. The lack of differences in fruit set on caged trees with and without bees as well as the failure to increase set with supplemental self-pollinations demonstrated that bees are not necessary to transfer the self-fertile pollen. It was concluded that inadequate pollination, in terms of quantity or quality, is not responsible for the sporadic poor yields of this cultivar.