EFFECT OF CHEMICAL AND HAND THINNING ON MATURITY, YIELD AND FRUIT QUALITY OF PEACHES (PRUNUS PERSICA (L.) BATSCH.)

Abstract

With a view to improve marketable yield, fruit maturity, quality and to maintain vigour of the trees, three low chill peach cultivars, namely 'Flordaprince,' 'Partap' and 'Shan-i-Punjab' were subjected to thinning. Thinning of flowers and fruits was done using chemicals (urea, ammonium thiosulphate, dormex) at different concentrations and by hand. These chemicals were sprayed at full-bloom. Hand thinning of flowers/ fruits was done starting from pink bud stage of flowers and continued at weekly intervals till one week after pit hardening stage of each variety. Among the chemicals, dormex (0.5%), urea (12%) or ammonium thiosulphate (6%) for 'Shan-i-Punjab' cultivar and urea (8%) or ammonium thiosulphate (4%) for cultivar 'Partap' when applied at full-bloom were found to be the best treatments. Whereas, the best time to thin fruits by hand was found to be 3rd to 4th week of February for 'Flordaprince,' 2nd to 3rd week of March for 'Partap' and 3rd to 4th week of March for 'Shan-i-Punjab' cultivar of peach. As a result of thinning, the fruit maturity was advanced by 4-7 days and there was an increase in fruit size by 20-35 percent in different cultivars as compared to unthinned fruits.