Response of grapes to micro-irrigation under different evaporation replenishment rates

Abstract

The field experiment was conducted at the Indian Institute of Horticultural Research, Hessaraghatta, Bangalore during 1999-2000 to study the “Response of grapes to microirrigation under different evaporation replenishment rates”. The fruit yield of grape was higher with drip irrigation (30.20 t ha-1) compared to microjet irrigation (29.94 t ha-1). The yield attributing parameters like number of branches per plant (90.75), average bunch weight (473.33 g), 100 berry weight (380.99 g), berry diameter (22.23 cm2) and berry length (31.30 cm2) were higher with drip irrigation. Increasing the evaporation replenishment increased the fruit yield and other yield parameters like, the fruit yield was higher with 100 per cent evaporation replenishment (31.98 t ha-1) which was on par with 75 per cent evaporation replenishment (31.53 t ha-1), but it was lower with 50 per cent evaporation replenishment (26.69 t ha-1). Evaporation replenishment rates did not influence the growth parameters like leaf area of index leaf, fresh weight of index leaf, dry weight of index leaf, dry matter content of index leaf and pruning weight although they were higher with 100 per cent evaporation replenishment. The total soluble solids was marginally higher with drip irrigation (15.43%) compared to microjet irrigation (15.37%), but the titrable acidity did not vary with the method of irrigation (0.34%). The sugar : acid was higher with drip irrigation (45.11) compared to microject irrigation (44.86). Irrigation scheduled with an evaporation replenishment rate of 75 per cent either with microject or drip irrigation resulted in higher yields. The water use with 75 per cent evaporation replenishment was 945.75 mm.