Effect of Plant Growth Regulators on Fruit Retention, Yield and Physico-Chemical Characteristics of Fruits in Ber 'Banarasi Karka' Grown in Close Spacing

Banarasi Karka cultivar of ber is the choicest variety in the state of West Bengal. The cultivar produces good crop and quality fruits during January-February. One of the main constraints in fruit production in this cultivar is occurrence of high natural fruit drop (about 70%). It is established that plant growth regulators can significantly change the hormonal status of the plant resulting good fruit retention and thereby improve the fruit yield and quality. A study was taken up on a 6-year-old Banarasi Karka cultivar of ber raised through in situ budding on 2 year old rootstock with the spacing of 3.5 m (row to row) and 4.5 m (plant to plant). There were seven treatments with two growth regulators viz., NAA at 25, 50 and 100 mg/L; GA at 10, 20 and 40 mg/L and control (water spray). These chemicals were thoroughly sprayed three times just after fruit set at 21 days interval. Results of two years of investigation revealed that application of NAA at 25 mg/L gave significantly highest fruit retention (75%) which resulted in highest fruit yield of 120.5 quintals as against 64.7 quintals/ha in control. No beneficial effect of GA on fruit retention or improving fruit yield was observed. But, fruit quality was significantly improved.