Yield gap analysis and resource use efficiency in irrigated versus rainfed mustard production

Abstract:

Consider a crop where farmers routinely harvest barely half of what the same genotype can produce under optimal management that is the reality of Indian mustard across vast rainfed tracts of central India. This research quantified yield gaps and compared resource use efficiency between irrigated and rainfed mustard (Brassica juncea cv. Pusa Bold) at two sites: Raipur (Chhattisgarh) and Udaipur (Rajasthan) during Rabi 2022-2023. The irrigated system achieved 1867 kg/ha against a rainfed yield of 1243 kg/ha, leaving exploitable yield gaps of 513 kg/ha (Gap I: attainable vs. irrigated actual) and 624 kg/ha (Gap II: irrigated vs. rainfed actual). Nitrogen use efficiency was 42.3 and 31.8 kg seed/kg N for irrigated and rainfed systems respectively. Water productivity reached 8.6 kg seed/m³ under irrigation versus 4.3 kg/m³ under rainfed conditions. Closing these gaps through supplemental irrigation and improved fertiliser timing could add an estimated 0.38 million tonnes to India's annual rapeseed-mustard output.