Sustainability assessment of cotton based intercropping systems for productivity and profitability using different quantitative indices under semi-arid vertisols

Field experiments were conducted to evaluate cotton (Gossypium spp.)-based intercropping systems with greengram [Vigna radiata (L.) Wilezek], blackgram [Vigna mungo (L.) Hepper], pigeonpea [Cajanus cajan (L.) Millsp.] maize (Zea mays L.) and soybean [Glycine max (L.) Merrill.] as intercrops in semi-arid (moist) Vertisols at Khedbrahma (Gujarat) and soybean and pigeonpea as intercrops in semi-arid (moist) Vertisols at Akola during rainy seasons of 2008–09, 2009–10 and 2010–11. The intercropping systems were evaluated for superiority based on cotton equivalent yield (CEY), rainwater use efficiency (RWUE), monetary returns, sustainability yield index (SYI) and three competition indices, viz. land equivalent ratio (LER), relative crowding coefficient (RCC) and competition ratio (CR). At Khedbrahma, cotton + blackgram (1:1) was found to be an efficient system with significantly higher mean CEY (983 kg/ha), net returns (18,893/ha), benefit: cost ratio (2.68), RWUE (2.23 kg/ha-mm), higher SYI (70.4) and LER (1.44) and lower total CR (2.17). At Akola, cotton + soybean (1:1) was found to be efficient with significantly higher mean CEY (1,609 kg/ha) besides higher net returns (35,177/ha), benefit: cost ratio (2.94), RWUE (3.68 kg/ha-mm), higher SYI (34.1) and LER (1.31) and lower total CR (2.19). Further, the multi-tier system of cotton + soybean + pigeonpea + soybean (3:2:2:2) was the second best with higher productivity, benefit: cost ratio and RWUE. Cotton + blackgram (1:1) at Khedbrahma and cotton + soybean (1:1) at Akola were identified as efficient intercropping systems and could be adopted under similar agro-ecological settings in the respective domains.