EFFECT OF GA3 ON VEGETATIVE GROWTH, MORPHOLOGICAL ATTRIBUTES AND SEED YIELD OF BLACK CUMIN (Nigella sativa L.)

Abstract

A field experiment was conducted at the research field of Sher-e- Bangla Agricultural University, Dhaka during the period from November 1, 2016 to April 30, 2017 to investigate the effects of GA3 on vegetative growth, morphological attributes and seed yield of black cumin (Nigella sativa L.). The experimental treatments were consisted of eight different doses of GA3 viz., 0 ppm (distilled water spray), 20 ppm, 40 ppm, 60 ppm, 80 ppm, 100 ppm, 120 ppm and 140 ppm. The variety BARI kalojira-1 was used as planting material and different doses of GA3 were applied on the plants at 40 days after sowing. The experiment was laid out in Randomized Complete Block Design with 3 replications. GA3 had significant effect on vegetative growth, morphology, yield and yield contributing characters of black cumin. Plant height at 50 % flowering stage, number of leaves at 50 % flowering, number of primary branches plant-1, dry weight plant-1, days to 1st and 50 % flowering, number of capsules plant-1, number of seeds capsule-1, weight of seeds plant-1, 1000-seed weight were found maximum from the application of GA3 at 120 ppm which was closely followed by 100 ppm GA3. A strong positive correlation of seed yield was observed with capsules plant-1, seeds capsule-1, weight of seeds plant-1 and 1000-seed weight. Application of GA3 at 120 ppm gave the maximum seed yield (2.95 t ha-1) which was statistically identical with GA3 at 100 ppm (2.85 t ha-1) and the worst seed yield was recorded from control (distilled water) (1.38 t ha-1). Application of GA3 @ 120 ppm and @ 100 ppm increased seed yield over control by 53.32 % and 51.61 %, respectively. The highest stover yield was also recorded from GA3 at 120 ppm closely followed by 100 ppm GA3. Finally, it may be said that; the foliar application may be a better option for improving the seed yield of black cumin under prevailing climatic condition of Bangladesh.