Augmentation of Growth and Flowering Characteristics for off-season Flower Production in Jasmine (J. sambac (L.) Aiton.) through Pruning and Growth Regulators.

An experiment was conducted at the Department of Horticulture, UAS, GKVK, Bengaluru during 2022-23 to analyse the effect of pruning and growth regulators on 'off season' flower production in Jasminum sambac (L.) Aiton. Three pruning treatments were imposed, viz., during the second fortnight of August (P₁), October (P₂) and December (control). Growth regulator treatment included GA3 at 100 (G1), 150 (G₂), and 200 ppm (G₃); Cycocel at 500 (G₄), 750 (G₅), and 1000 ppm (G₆) along with double distilled water (Control, G7); there were sprayed at 15 days after pruning. The 21 treatments comprising of pruning schedule and growth regulators was laid out in Factorial Randomized Complete Block Design (FRCBD) with three replications. Among different vegetative characteristics, P₃G₃ (December pruning + GA3 at 200 ppm) had recorded maximum plant height and plant spread in E-W and N-S directions at 30, 60 and 90 days after pruning, respectively. Number of primary branches per plant showed no significant difference among the treatments. Higher number of secondary branches per plant was recorded in P3G6 (December pruning + Cycocel at 1000 ppm). Flower characteristics viz., days taken for bud initiation (35.00 days), first flowering (47.00 days) and 50 per cent flowering (71.00 days) were minimum in December pruning along with foliar application of Cycocel at 1000 ppm (P₃G₆) and significantly different from others. Total duration of flowering (250 days) was maximum in plants pruned during October month with application of Cycocel at 1000 ppm (P₂G₆) with significantly increased in off season flower yield (December to February) per plant (0.141 kg) and per ha (0.628 t). [ABSTRACT FROM AUTHOR]