Effect of Manual and Chemical Thinning on Graded Yield and Fruit Quality in Nectarine [Prunus persica (L.) Batsch var. nucipersica] Cv. May Fire

Abstract

The present investigations were conducted on 10-year-old May Fire nectarine plantations at the experimental orchard of Horticulture Research Station, Kandaghat, during 2011-2012. Experimental trees were given the treatments viz. retention of 3, 4 and 5 fruits per fruiting shoot after selective removal of fruits with hand at pea stage, foliar application of Ethrel at 200 and 300 ppm, NAA at 40 and 60 ppm and Thidiazuron at 20 and 40 ppm two weeks after petal fall and un-thinned control with three replications in Randomized Block Design. Foliar spray of NAA at 40 ppm significantly increased the per cent fruit thinning, the yield of "A'' grade fruits, fruit size, weight, volume over the control. The contents of total soluble solids, total sugar and TSS/acid ratio were highest and titratable acidity lowest in the fruits from trees treated with NAA at 60 ppm and Ethrel at 300 ppm in the years 2011 and 2012, respectively. However, the higher increase in leaf to fruit ratio was recorded under the treatment of hand thinning to retain 3 fruits per shoot.