Assessment of Residual Effect of Paclobutrazol on the Growth, Flowering, Yield and Quality of Litchi

Abstract

This study focuses on the residual effect of paclobutrazol on the vegetative growth, flowering, yield, and quality of litchi grown at the Horticulture Research Centre, Patharchatta, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar during the period 2016– 2019. A total of 45 litchi trees were included in this experiment. The treatments consisted of four doses of paclobutrazol at 1.0 g a.i. (20 ml/tree), 2.0 g a.i. (40 ml/tree), 3.0 g a.i. (60 ml/tree), and 4.0 g a.i (80 ml/tree) per meter canopy diameter. The doses were applied on three dates, September 15, October 15, and November 15, through soil drenching in the years 2016 and 2017, subsequently. Plain irrigation water was applied in the basins of trees which served as control. The results show that application of paclobutrazol at 3.0 g and 4.0 g a.i. Per meter canopy diameter during 2016 and 2017 were the most effective in suppressing vegetative growth as compared to control. Higher doses of paclobutrazol persisted in the soil for longer duration and consequently affected flowering and fruiting during 2019. The trees treated with higher doses of paclobutrazol displayed more residual effects on flowering, fruiting, yield, and quality parameters during 2019.