Effect of foliar feeding of nutrients and plant growth regulators on physico-chemical quality of sardar guava grown in red and lateritic tract of West Bengal

This study was designed to determine the effect of foliar feeding of nutrients and plant growth regulators on physico-chemical quality of guava cv. sardar grown in red and lateritic tract of West Bengal. Nutrients and plant growth regulators were administered three times. viz. before flowering, followed by second and third at fruit setting and three weeks after fruit setting. Experimental results revealed that foliar feeding of nutrients and plant growth regulators significantly increased the fruit length, diameter, individual fruit weight and ultimately crop yield. Maximum (6.24 cm) length of fruit was obtained with treatment urea + K2SO4 +Zinc + NAA followed by urea + K2SO4+Zinc. This treatment also found effective in maximizing individual fruit weight and crop yield. However, spraying of urea + K2SO4 + Zinc + GA(3) or urea + K2SO4 + GA(3) was also equally effective in this respect. The highest cost : benefit ratio of 1 : 34.92 was obtained with the spraying of urea + K2SO4 + Zinc + NAA followed by 1 : 34.06 with urea application. The bio-chemical constituents were also influenced by different spraying of nutrients and growth regulators. Maximum TSS (10.85 degrees B) and total sugar (7.25%) were obtained with K2SO4 treatment followed by urea + K2SO4+ Zinc + NAA. Reduction of titratable acidity was found under NAA alone on in combination with urea + K2SO4 + Zinc. Plants treated with urea + K2SO4+ Zinc + NAA showed maximum (135.42 mg 100 g(-1) fruit) ascorbic acid content followed by NAA 50 ppm. Therefore, it is suggested to apply urea + K2SO4+ Zinc + NAA for their beneficial effects on yield and qualities of fruits and also to offer better return to the growers.