Managing Citrus Tree Growth with Hedging and Plant Growth Regulators: Strategies for Reducing Psyllid Feeding and Huanglongbing Infection

摘要

Reducing excessive vegetative growth that is produced annually by citrus trees in Florida would reduce the opportunities for asian citrus psyllid (Diaphorina citri Kuwayama) reproduction and thereby, the spread of huanglongbing. Excess tree growth isroutinely removed through hedging; branch regrowth can be reduced after hedging in the fall season under Florida conditions because of the onset of cool temperatures. Additionally, late summer hedging may synchronize a final late-season flush; thus, reduce new flush leaves present during the winter to support overwintering psyllids. We determined timing effects of fall and early winter hedging of 'Hamlin' orange trees on vegetative growth flush and subsequent yield during a 2-year period. None of thehedging times tested stimulated a growth flush or significantly affected yield by hedging time in either year.