Effect of Drip Irrigation Levels on Yield of Salad Cucumber under Naturally Ventilated Polyhouse

Abstract

An experiment was conducted to study the yield response of salad cucumber under different drip irrigation levels to determine the most suitable irrigation requirement for salad cucumber grown under naturally ventilated polyhouse. Drip irrigation applied at the rate of 2 litre plant -1 day -1 to the control plants was reduced by 5, 20, 35 and 50% by applying corresponding irrigation rates of 1.9, 1.6, 1.3 and 1 litre plant -1 day -1 under different treatments. Lowering irrigation level to 65% sustained the production and increased water use efficiency without decreasing the yield of cucumber. However, irrigation level of less than 65% reduced the yield without increasing water use efficiency. The maximum fruit number (49), fruit weight (7.194 kg plant -1 ) and fruit yield (88.8 t ha -1 ) were obtained from drip irrigation level of 65% (1.3 litre plant -1 day -1 ) and the lowest fruit number (35), fruit weight (5.043 kg plant -1 ) and fruit yield (62.26 t ha -1 ) from drip irrigation level of 50% (1 litre plant -1 day -1 ), with the lowest water application rate . Irrigation treatments had significant effects (P < 0.05) on yield. However, interaction within groups was found to be non significant. There were significant positive correlations (P < 0.01) between fruit number, fruit weight and fruit yield. The total quantity of water applied through 65% drip irrigation level was 144.4 mm and which showed 35 per cent water saving over control with highest water use efficiency (6148.31 kg ha -1 cm -1 ) and Benefit Cost (BC) ratio (3.41).