Optimizing Soil Moisture Regime for Vegetable Cowpea Intercropped with Spring Planted Sugarcane

Three intercropping systems viz., sugarcane + vegetable cowpea (Cv. Pusa Komal), sugarcane + black gram (Cv. PU3O) and sugarcane + green gram (Cv. K 851) were evaluated at four irrigation schedules viz., Irrigation water to Cumulative Pan Evaporation (IW/CPE) ratio of 1.2, 1.0 and 0.8 and irrigation at Critical Physiological Stages (CPS) of intercrops. The number of millable cane and yield attributes as well as yield of sugarcane under sugarcane + vegetable cowpea intercropping system was at par to that intercropped with green gram and produced 94.2 thousand number of milliable canes/ha of 1 66.2cm average cane length with 73.1 t/ha yield of sugarcane. Intercropped cowpea produced 26.4q vegetable pods/ha while green gram yielded 5.67q grain/ha. The cane equivalent yield under this system worked out to be 85.3 t/ha. Highest yield of intercrop vegetable cowpea (29.5q/ha) were recorded with irrigation scheduled at IW/CPE ratio of 1.2. Maximum irrigation water use efficiency (31 7.9 kg/ha-mm) occurred by irrigating the intercrop at critical physiological stages. Sugarcane + vegetable cowpea and sugarcane + green gram intercropping systems proved highly irrigation water use efficient ones with Water Use Efficiency of 188.2 and 1 92.0 kg/ha-mm. These intercropping systems also fetched the higher net income (Rs.46371 and 48822/ha) with B: C ratio of 1.33 and 1.42 respectively.