Changes in soil properties, productivity and profitability as influenced by the adoption of site-specific integrated crop management technology in turmeric (Curcuma longa L.) in Eastern Himalayan acidic Inceptisol

Abstract

Turmeric (Curcuma longa L.), a major spice crop in the North-Eastern Hill Region (NEHR) of India, plays a vital role in the economy of tribal farmers of this region who though practise its traditional farming. The predominance of acidic Inceptisol in NEHR further deteriorates the yield and quality of this crop fetching poor remuneration to the tribal growers. Optimal and balanced plant nutrition holds the key to realize sustainable and cogent crop yields with better quality. Hence, multi-location ‘on-farm’ experimentation on integrated crop management (ICM) technology in turmeric var. Mega Turmeric-1 were conducted in NEHR (India) during 2019 and 2020 to assess the impact on the changes in soil properties, turmeric rhizome productivity and farm profits compared to farmers’ practice (FP). The ICM technology significantly improved the available-NPK besides a substantial increase in the secondary nutrients (exchangeable Ca & Mg, and available-S) over FP. However, ICM had favourable nominal changes in the soil chemical properties (pH, EC, SOC, CEC, free Fe & Al oxides) compared to FP. On an average, the adoption of ICM satisfactorily augmented the yield attributes and turmeric rhizome yield (20.9 Mg ha−1) with a hike of ~27% over the FP besides a quantum gain in net returns to the tune of US $ 875 ha−1 over FP with an enhancement of ~34.4% compared to FP. Correlation analysis indicated that SOC, available-NPK, Ca, S and B exhibited a highly significant positive correlation with turmeric rhizome yield. Multivariate PCA exhibited that N, SOC and K were the most important soil properties attributing to the turmeric rhizome yield. Stepwise multiple regressions indicated that N, SOC and K contributed to the tune of 47.7%, 21.9% and 8.6%, respectively in augmenting the turmeric rhizome yield. Overall, the adoption of ICM technology is highly effective in improving the soil chemical properties, turmeric rhizome yield and economic returns as compared to farmers’ practice in an Eastern Himalayan acidic Inceptisol.