Fusao Mizutani

Dwarfing Peach Trees Grafted on Vigorous Rootstocks: Dwarf Peach Trees Development Fusao Mizutani

These studies were conducted using two, five and nine- year-old peach trees grafted on vigorous peach rootstocks. The site was in the Ehime University Experimental Farm, Japan. Slender spindle type pruning, partial bark ring and growth inhibitors were employed in peach trees. Summer pruning was done in late July after fruit harvest from 2000 to 2004, and winter pruning was done in February 2001 to 2005. Pruned shoot weight, shoot length and flower number were less in summer than in winter-pruned trees, while chlorophyll content was higher in summer-pruned than in winter- pruned trees. Summer pruning caused earlier shoot and fruit (ovary) growth in the following spring. Mineral nutrient and carbohydrate content in new leaves and shoots were higher in summer-pruned trees. Summer pruning resulted in less shoot growth leading to improved light penetration as compared with winter-pruned trees. This seemed to accelerate fruit maturation and fruit quality having dwarf peach tree. Besides, partial bark ring and growth inhibitors showed dwarf size of peach trees having early flower blooming, higher abscisic acid (ABA) and lower cytokinin content.