Effect of pruning on fruitset and shoot growth of ‘Packham's Triumph’ pear trees

Abstract

The severity of dormant pruning of two-year-old shoot units on young bearing Pyrus communis L. cultivar ‘Packham's Triumph’ pear trees was varied. The location of new shoot growth was manipulated by removing new shoots from various sections of 2-year-old shoot units. Shoot units were pruned at intervals before and after anthesis. The number of styles pollinated per flower on pruned and unpruned shoot units was varied. Percentage fruitset increased with pruning. Poor correlation between percentage fruitset and the number of new shoots indicated that competition between shoots and fruits alone could not explain the variable fruitset. The location of new shoots relative to fruits was important. Pruning delayed 3 weeks or longer after anthesis failed to improve fruitset. Pruning increased the set of true parthenocarpic fruit.