PACLOBUTRAZOL INFLUENCES FLOWER INDUCTION IN DURIAN, DURIO ZIBETHINUS MURR.
Flowering in the treated trees occurred 14 to 45 days earlier than that of the untreated. Flowering response to paclobutrazol is more readily in higher rates. In general, as climatic conditions prevail, a pre-requisite of 10 to 14 days of continuous dry period is required for untreated trees to induce flowering. In contrast, an interupted 3 to 7 days continuous dry period after chemical treatment is sufficient to promote flowering in the treated trees. When compared with the untreated control trees, the number of flowers per tree in the trees treated with paclobutrazol was increased by 29 to 64 %. It has been observed that fruit set and fruit development were not influenced by paclobutrazol application, however, the rate of flower and fruit development was somewhat delayed. Results of the experiment indicated that a successful induction of flowering using paclobutrazol involved the degree of vegetative growth suppression, concentration and time of chemical application and an interruption of continuous dry period.