APPLICATION OF GA4+7 TO STEM ENHANCES CARAMBOLA SEEDLING GROWTH

Growth response of containerized carambola (Averrhoa carambola L.) seedlings to GA4+7 applied to trunks in lanolin paste were studied under glasshouse conditions. Gibberellic acid at 0, 250, 500, or 750 mg.liter-1 and an untreated control (no lanolin) were used. Internode length and increases in plant height and trunk cross-sectional area (TCA) did not differ for control and 0 mg.liter-1 plants, but mostly increased with concentration of GA. Increase in TCA was determined in a second study with control and treated plants, using 500 mg GA/liter. Mean recommended graftable size (7 mm) was reached in 47 days in plants that were GA treated, and 93 days in control plants, suggesting that GA may be used to shorten nursery time for producing graftable carambola seedlings. Chemical name used: gibberellic acid (GA4+7).