EFFECTS OF GIBBERELLIC ACID (GA3) ON THE GROWTH, FRUIT YIELD AND QUALITY OF STRAWBERRY (FRAGARIA × ANANASSA) IN A SUB-TROPICAL ENVIRONMENT

Abstract

Strawberry (Fragaria x ananassa) is a widely adapted small fruit grown from the low-altitude of tropics and subtropics to high-altitude in cold continental areas. Despite its nutritional benefits, little research has been undertaken to facilitate its wide scale production in sub-tropical environments. This experiment was laid down in a Randomised Complete Block Design (RCBD) with four replications. Its aim was to determine the effects of different concentrations (0, 25, 50, 75 ppm) of gibberellic acid (GA3) on growth, yield and quality of strawberry. The results revealed that plants treated with 75 ppm GA significantly (P < 0.05) had more growth in number of leaves, petiole length, plant spread and leaf area. Less leaf nitrogen (1.78%) and chlorophyll content index (25.01) were observed in GA treated plants with 75 ppm. Control plants sprayed with distilled water took more days to produce first flower (62.25 days) and fruit (69 days) as compared to GA treated plants which also produced fruits with more weight and yield which increased with increasing concentrations. Titratable acidity of the fruits was significantly (P < 0.05) lower in plants treated with 75 ppm GA3 and had higher vitamin C (71.88 mg/g) and total soluble solids (6.90 Brix). Results from GA treated plants at 50 ppm were the best in this experiment but more research needs to be done in the open field as this one was done in a lathhouse with plants grown in containers; differences might be observed in the field and there is need for more research on strawberry and bioregulators in the different ecological areas of Swaziland.