Drip irrigation and mulches influence on performance of tomato (Lycopersicon esculentum) in arid Rajasthan

A field experiment was conducted at Bikaner (Rajasthan) during the rabi season of 2007–08 to investigate the influence of drip irrigation and different mulches on the growth, yield, water use efficiency and economics of tomato (Lycopersicon esculentum Mill.) hybrid ‘Alfa’. The experiment consisted of five irrigation volumes viz., recommended surface irrigation and drip irrigation at 55, 70, 85 and 100% evapo-transpiration (ET) in main plots and three types of mulching viz., no mulch, kheep @ 10 tonnes/ha as organic mulch and black polyethylene (25 micron) in sub plots. The results reveal that drip irrigation at 85% ET gave significantly higher plant growth, yield attributes and fruit yield (788.9 q/ha) compared with the surface irrigation (546.5 q/ha). Among mulches, organic mulch registered the significantly highest plant growth, yield attributes and fruit yield (832.1 q/ha). Use of drip irrigation at 85% ET plus organic mulch further raised the fruit yield up to 118.7% compared to surface irrigation with no mulch. The total water requirements for tomato using 55, 70, 85 and 100% ET levels of drip irrigation were 55.4, 72.9, 86.7 and 101.1 liters/plant respectively. The highest water-use efficiency was recorded under drip irrigation at 55% ET (19.8 q/ha-cm) and organic mulch (16.0 q/ha-cm). Compared to surface irrigation, drip irrigation at 80% ET resulted into saving of 14.1% water and produced 42.8% higher fruit yield. The study showed that the maximum net return of 256345/ha could be obtained with drip irrigation at 85% ET with a B:C ratio of 1.9. The maximum net returns (282536/ha) and B:C ratio (2.1) of different mulches was recorded with organic mulch. However, where the availability of water is limited, drip irrigation at 70% ET could be applied to obtain a net return of 235315 with a B:C ratio of 1.7 and in water scarcity areas, where the land is not a constraint, drip irrigation at 55% ET could be resorted to as it would command an additional area of 0.82 ha with additional net return of 44526/ha over surface irrigation.