Influence of Growth Retardants on Vegetative Growth of Apple (Malus × domestica Borkh.) Cultivars under High Density Planting System

The present investigation entitled “Regulation of growth, fruiting and biochemical characteristics in Fuji Zehn Aztec and Red Braeburn apple cultivars through application of growth retardants under high density planting system” was conducted in the Experimental Block of the Division of Fruit Science at Sher-e-Kashmir University of Agricultural Sciences & Technology of Kashmir, Shalimar campus, Srinagar (J&K) during the years 2020 and 2021. Four-year-old apple cultivars Fuji Zehn Aztec and Red Braeburn on M9-T337 planted at a distance of 3×1 meter of uniform age, vigor and girth were used for the study. The experiment comprising of seven treatments viz., control, prohexadione-calcium @125 ppm, prohexadione-calcium @250 ppm, prohexadione-calcium @500 ppm, paclobutrazol @200 ppm, paclobutrazol @400 and paclobutrazol@600 ppm was laid out in randomized complete design with three replications. The chemicals were sprayed one week after petal fall, three weeks after 1st spray and three weeks after 2nd spray. Paclobutrazol@600 ppm resulted in maximum reduction in vegetative growth parameters in both the apple cultivars under study.