Integrated nutrient management in maize (Zea mays)–gobhi sarson (Brassica napus ssp oleifera var. annua) cropping system under rainfed condition

Field experiments were conducted in Kangra, Himachal Pradesh, India, during the 1998/99 and 2000/01 cropping seasons, to work out an integrated nutrient management schedule for maize-gobi sarson (Brassica napus subsp. oleifera var. annua) cropping system under rainfed conditions. The total grain production was higher (110.5 q/ha) when both crops in the system were given 150% of the recommended NPK and was 28 and 26% higher over the recommended fertilizer application in maize and gobi sarson, respectively. However, an application of 150% of the recommended NPK to maize and 100% NPK + 10 t/ha farmyard manure (FYM) to gobi sarson also resulted in statistically similar grain yield (108 q/ha). Application of 10 t FYM along with 100% NPK either to one or both crops increased the system productivity by 7.7% compared to the 100% NPK application. The N, P and K uptake in the system was higher when both crops in the system were given 150% NPK, followed by 100% NPK + 10 t FYM/ha application. Higher gross returns (Rs 75 251) and benefit:cost ratio (2.68) were obtained when both crops in the system were given 150% of the recommended NPK rate. Application of the recommended NPK fertilizer rate to both crops gave lower gross returns (Rs 56 786). A benefit:cost ratio of 2.18 was most practical under limited resources.