Growth and Yield Response of Mango to Paclobutrazol Application Under Subtropical Climate

Use of paclobutrazol has been recognized as potential growth regulator to increase fruit production. This research was conducted to evaluate different application method (soil drenching, collar washing, stem injection or stem pitting) and doses (10g or 15 g per tree) of paclobutrazol on mango trees under subtropical conditions of Pakistan. Paclobutrazol was applied @ 10g or 15g per tree to eighteen years old mango trees (Mangifera indica L.) cv. Langra, grown under same agro-climatic and cultural conditions, located at Experimental Fruit Orchard, Institute of Horticultural Sciences, University of Agriculture, Faisalabad (Latitude 31°-26´N  and Longitude 73°-06´E) Province Punjab, Pakistan. The parameters under study included, leaf nutrient contents (N, P, K, Ca), vegetative growth (flushing time, flushing intensity, canopy volume), reproductive growth (time and intensity of panicle emergence, floral malformation intensity, flower sex ratio, fruit setting, fruit number, fresh fruit weight, yield) and quality parameters (total carotenoids, TSS/TTA ratio, ascorbic acid, sugars and organoleptic attributes). It has been presented that paclobutrazol application through stem injection method @ 10 g per tree significantly affected N, P, K leaf contents with reduced vegetative growth (22% lower canopy volume) and improved reproductive growth (11% increase in fruit production) of the mango trees without adversely affecting mango fruit quality, while it also remarkably reduced threatening disorder of mango malformation (30%) of inflorescence.