Response of growth regulators and micronutrients on yield and physico-chemical quality of Ber (Zizyphus mauritiana Lamk) cv. BAU Kul-1

Abstract

Ber (Zizyphus mauritiana Lamk.) is an indigenous delicious, nourishing fruit grown widely throughout the India but faces heavy fruit drop due to several biotic and abiotic stress factors resulted in declining trend of ber pro-duction over the year. Keeping these facts in foreground, replicated field experiment was conducted during 2013-14 and 2014-15 at HRS, Mondouri, BCKV, West Bengal with eleven treatments consist two different levels of NAA, GA3, 2,4-D, ZnSO4 and H3BO3 along with a control (water spray). Results of investigation revealed that application of 2,4-D @ 10 mg/l recorded highest fruit set (48.80%). Maximum fruit retention (42.83%) and total no. of fruits/tree (514) were obtained with the application of NAA @ 20 mg/l. Application of GA3 @ 20 mg/l recorded significantly (p?0.05) higher yield (30.67 kg/tree), fruit weight (60.5 g), fruit length (5.8 cm), fruit breadth (5.1 cm), pulp to seed ratio (13.9) and specific gravity (1.104) as well as economic returns over control during both the year of experiment. Among the treatments H3BO3 at 0.4% recorded the highest TSS (11.7°Brix), total sugar (8.33%), reducing sugar (5.21%) and TSS: Acid (107.36) ratio with lowest fruit acidity (0.10 %) whereas highest vitamin-C content of fruit was recorded with GA3 at 20 mg/l (64.68 mg / 100 g) followed by NAA at 20 mg/l. Results suggest that twice spraying of GA3 @ 20 mg/l and H3BO3 at 0.4% is vital for optimizing yield components, yield and quality of ber (cv. BAU Kul-1) in trans-Gangetic plains of West Bengal.