Response of soil applied paclobutrazol for enhancing vegetative and reproductive growth in Kesar mango (Mangifera indica L.)

Abstract

Paclobutrazol (PBZ) is a growth regulator used to control vegetative growth, stimulating the reproductive capacity of plants. PBZ has been widely marketed throughout the tropics to stimulate mango flowering. A field experiment was conducted during 2023-24 on a well-established ten-year-old mango orchard at the Department of Horticulture, College of Agriculture, Latur, to Response of soil applied paclobutrazol for enhancing vegetative and reproductive growth in Kesar Mango (Mangifera indica L.). The experiment followed a factorial randomized block design with two factors: the First factor being the concentration of paclobutrazol (C1: 1 ml a.i./m², C2: 1.5 ml a.i./m² and C3: 2 ml a.i./m²) and the Second factor being the time of application (M1: 15th July, M2: 1st August and M3: 15th August), with three replications. The treatments were applied as per the plan and observations on flowering, fruiting, yield and quality parameters were recorded. The results revealed that the application of paclobutrazol at 2 ml a.i./m² resulted in significantly reduced shoot length (10.28 cm), internodal length (2.17 cm), minimum days to panicle emergence (46.89), maximum number of panicles per tree (621.68) and the longest panicles (31.33 cm). In terms of timing, application on 15th July showed the shortest shoot length (19.77 cm), internodal length (2.29 cm), minimum days to panicle emergence (46.33), the maximum number of panicles per tree (618.68) and the longest panicle length (34.69 cm). These results suggest that the application of paclobutrazol at 2 ml a.i./m² on 15th July optimizes vegetative growth and flowering in mango cv. Kesar. However, the interaction effect of paclobutrazol concentration and time of application showed no significant effect on vegetative and flowering parameters. The interaction effect of paclobutrazol applied at 2 ml per meter of canopy diameter on July 15th was the most effective in achieving early emergence of panicles. This study suggests that the multiple soil application of PBZ was effective in promoting vegetative and flowering parameters in Kesar mango, can help early flowering and more number of flowering shoots.