Performance of Intercrops under Different Spacings of Jatropha curcas Plantations in Tamil Nadu, India

Background: Non-edible oil as biodiesel helps to meet the energy demand and to reduce environmental degradation. Jatropha curcas is one of the potential oil yielding plant which can be grown under agroforestry systems without affecting food production. Hence the current study aimed to find out compatible intercrop under J. curcas and optimum spacing of J. curcas for intercropping. Methods: A study was carried out in three and a half-year old J. curcas plantation. Different spacings of J. curcas viz., 3m × 3m, 4m × 2m and 4m × 3m and different legumes viz., blackgram, greengram, cowpea, groundnut and oilseed crops viz., gingelly and sunflower were evaluated in split plot design. Result: Growth and yield of intercrops, available soil N, P and uptake of N, P, K by intercrops were significantly higher at wider spacing of J. curcas (4m × 3m). Among the intercrops, groundnut recorded higher uptake of N (67.3 kg ha-1), P (19.9 kg ha-1) and K (65.3 kg ha-1). Groundnut produced a significantly higher yield (885 kg ha-1) followed by cowpea (630 kg ha-1). The study found that planting of J. curcas at 4m × 3m spacing and intercropping with groundnut is a compatible and profitable J. curcas based agroforestry system.