Using Paclobutrazol and Leaf-to-fruit-ratio as Tools for Improving Yield and Quality of Non-dwarfing High-density Peach Orchards

Abstract

Excessive fruit set and foliar shading are the major deterrents to the economic productivity of peach orchards raised on vigorous rootstocks. With the objective of obtaining an appropriate level of crop together with the best quality fruit from the high-density peach orchards, studies were conducted in the sub-Himalayan subtropics of Himachal Pradesh, India. In the Experimental orchard of the Department of Fruit Science, the premium Early Grande cultivar raised on non-dwarfing wild peach seedling rootstock was selected for the studies. The orchard soil was sandy loam soil with normal physico-chemical characteristics. The experiment was laid out in RBD factorial experimental design with paclobutrazol (PBZ) and leaf-to-fruit ratio (LFR) treatment factors; three levels of PBZ viz. P1-1500 ppm, P2-2500 ppm, P3-0 ppm and four levels of LFR i.e. L1-30:1, L2-40:1, L3-50:1 and L4 - normal leaf number were tried. The findings revealed that 2500 ppm PBZ together with 40:1 LFR treatment not only reduced the number of days from full bloom to maturity but also improved fruit thinning. The fruit retention was recorded better with 1500 ppm PBZ and 50:1 LFR; however, the yield was recorded highest with 2500 ppm PBZ and 40:1 LFR treatments. This treatment combination also resulted in better overall fruit quality in terms of fruit surface colour, total soluble solids, firmness, acidity, sugars etc. The control over vegetative growth was also observed better under this treatment combination.