Soil management effects on soil quality and crop performance in dry sub-humid inceptisols of India

Maintaining soil productivity in coherence with soil quality at an optimal level for sustainable production systems is essential. A study was thus conducted to assess the sustainability of soil management treatments with maintenance of soil quality for three continuous in a sub-humid inceptisol in kharif maize. The maize experiment was laid out in randomized block design with the two tillage practices viz., minimum tillage (MT), conventional tillage (CT); two mulch practices viz., no mulch (NM) and straw mulch (SM) in four replications. Soil properties measured were bulk density (BD), infiltration rate (IR), organic carbon (OC), soil moisture (MC) and porosity (F). An attempt is made to select a few reliable indicators using multivariate statistical tools and assessment of soil quality index. Regression models of yield were calibrated for tillage and mulch treatments through monthly rainfall received during June to September and Infiltration rate (IR), organic carbon (OC), soil moisture (MC) and porosity (F). Soil moisture content emerged as the most discriminating soil quality indicator with maximum contribution to total variance of 72.5% followed by IR (17.9%) and porosity (9.6%). Based on analysis of variance, yield differences between tillage and mulch treatments and their interaction were significant in all seasons. The maize yield increased linearly with an increase in soil quality index (SQI) from 0.44 to 0.96. A high value of SQI indicated better soil quality and optimum yield. The minimum tillage plots had optimum SQI (0.78–0.96) and were sufficient for sustaining both maximum yield and soil quality. The predictive regression models result revealed that September rainfall had a significant negative effect on yield attained by tillage and mulch treatments. Ranks were assigned to tillage and mulch treatments for mean yield, prediction error, SYI and SQI over years. The study concluded that minimum tillage + mulch was superior with the lowest rank sum, SYI and SQI compared to other treatments. Acombined approach of SYI and SQI would be more effective for recommending a production management practice.