THE EFFECTS OF INTERFRUIT COMPETITION ON THE SIZE OF SWEET-PEPPER (CAPSICUM-ANNUUM-L) FRUITS

Two cultivars of sweet pepper were used to study the effect of interfruit competition on the components of fruit size under glasshouse and field conditions. Variation in interfruit competition was artificially simulated by removal of flower buds, flowers and set fruits on the first three flowering nodes of the pepper plant. The inhibitory effect of old fruits on the increase in weight, length, diameter and pericarp thickness of the younger ones was significant only from flower bud inception through Weeks 2 and 4 after fruit set in the glasshouse and field, respectively. Thereafter, the effect was not significant. Histological investigations revealed less cell multiplication activity and formation of fewer cell tiers, in the ovary wall of flower buds and small fruits under competition stress, than those under no competition. These results suggest that maintenance of vigorous vegetative growth from flower bud formation throughout fruit development might ensure sufficient organic nutrient supply to alleviate the stress on growth processes in developing buds, thereby reducing the variations in fruit sizes on upper nodes of pepper plant.