Ethephon - a best alternative for hand thinning to improve fruit set, colour and shelf life of apple

A field experiment was carried out to study the effect of hand and chemical blossom thinning on fruit set, colour development, shelf life and return bloom of Red Delicious apple fruit at the experimental farm, Division of Fruit Science, SKUAST-K, Shalimar. The experiment consisted of twelve treatments replicated three times with a single plot size in a randomised block design. Three methods of thinning viz., hand thinning, chemical thinning (NAA and Ethephon) and water thinning were tried at full bloom. Maximum fruit set (70%) was recorded in control while minimum (34%) was recorded in combined spray of NAA 10 ppm and Ethephon 150 ppm. Maximum pronounced fruit colour (4.0) and return bloom score (8.0) was recorded with fruits obtained from trees treated with 150 ppm Ethephon. Maximum percentage of A grade fruits (83.75%) was recorded with 60per cent hand thinning and with Ethephon 150 ppm (80%) whereas minimum percentage of A grade apples were found with control (59%). Among treatments, Ethephon at 150 ppm and 60per cent hand thinning were most effective in improving fruit quality attributes. Hand thinning being time and labour consuming practice was not possible in commercial horticulture. However, Ethephon 150 ppm was the best alternative for hand thinning and as such can be advocated to the orchardists for getting quality fruit of apple.