Effect of sowing time on yield, resource use efficiency, soil fertility status and economics of sorghum-based intercropping systems

A field experiment was conductedduring kharif 2011 at Dharwad (Karnataka) to study the effect of dry and normal sowing on yield, resource use efficiency, soil fertility status and economics of sorghum based intercropping systems under rainfed condition. Higher sorghum equivalent yield (SEY) was recorded in sorghum + soybean (2:2) (7.49 t ha⁻¹), followed by sorghum with blackgram (6.24 t ha⁻¹). Significantly lower light transmission ratio (LTR) was recorded when sorghum was intercropped with soybean (28.98% at 60 DAS) which indicated higher light interception as compared with other intercrops. The increase in land equivalent ratio (LER)was in the range of 34 to 43% (1.34 to 1.43) with different treatment combinations. Intercropping of soybean with sorghum in 2:2 row proportion resulted in significantly higher area time equivalent ratio (ATER) (1.27) indicating higher per day productivity from the system. Soil nitrogen, phosphorus and potassium status significantly improved when sorghum was intercropped with legumes as compared to sole sorghum. Dry sowing of sorghum intercropped with soybean recorded significantly higher gross return ( 104.8 x 10³ ha⁻¹), net return ( 81.6 x 10³ ha⁻¹) and B:C ratio (3.52).