Effect of Paclobutrazol on Flowering, Fruit Setting and Fruit Quality of Durian (Durio zibethinus Murr.) CV. Chanee.

Abstract

The effect of paclobutrazol on durian cv. Chanee was studied at a private orchard in Klaeng district, Rayong province for two consecutive years in 1988 and 1989. The results showed that the use of paclobutrazol together with surfactant did not enhance the time of flowering regarding to the application times, the positions in the trees where the chemical was applied and the ages of the treated trees as compared with the control treatment. The chemical applied at any time at various ages of the trees increased the percentage of branch bearing flowers, but the percentage of branch bearing fruits and the number of fruits per tree were not different among the treatments. Paclobutrazol applied with surfactant did not cause any difference in the mean fruit weight between the treated and untreated trees. However, the treated young trees appeared to have smaller fruits than those of the treated old trees. The length of fruit stalk of the paclobutrazol-treated trees was shorter than that of the untreated trees. The positions in the trees where the chemical was applied did not affect on the length of fruit stalk. The duration and frequency of the harvest were longer in the treated trees than in the control ones, but the position of the trees where the chemical was applied did not have any effect on the duration and the number of harvest. Paclobutrazol did not cause any differences in the percentage of flesh recovery, as well as quality of the harvested fruits.