Effects of cincturing, defoliation and summer pruning on vegetative growth and flowering of custard apple (Annona cherimola x Annona squamosa) in subtropical Queensland

Abstract

Trunk cincturing at monthly intervals from budbreak to mid January had no significant effects on vegetative flushing or flowering of 6-year-old custard apple trees (Annona cheriinola x Annona squamosa) cv. Pink's Mammoth in subtropical Queensland. In contrast, pre-budbreak defoliation with 1.0 g/L of 2- chloroethyi-phosphonic acid and 250 g/L of urea hastened, and post-budbreak defoliation and summer pruning delayed, shoot growth and flowering in 3-yearold custard apple trees, cv. African Pride. These responses were associated with a reduction in the number of flowers with defoliation and an increase after summer pruning. The main effect of summer pruning was to increase the number of subpetiolar buds which emerged on the new wood. There was no significant effect of treatments on the number of buds emerging from 1-year-old wood.