Impact of Live Mulch-Based Conservation Tillage on Soil Properties and Productivity of Summer Maize in Indian Himalayas

Abstract

Food security and soil sustainability are the prime challenges to researchers and policy planners across the globe. The task is much more daunting in the fragile ecosystem of the Eastern Himalayan region of India. Soil disturbance from conventional tillage reduces soil productivity and is not sustainable and environmentally friendly. Conservation tillage is regarded as the best crop production practice in the Indian Himalayas, where soil is very easily erodible. Zero tillage alone encourages the growth of different species of weed flora in fragile hill ecosystems. However, live mulching of a pulse crop under zero tillage may be a very beneficial practice, as it aids several soil quality benefits and promotes root proliferation with good crop harvest. Hence, a field investigation was carried out for 3 consecutive years to assess the impact of live mulch-based conservation tillage on soil properties and productivity of summer maize. Five tillage practices, viz. no-till (NT), NT and cowpea coculture live mulch (CLM), minimum tillage (MT), MT+CLM, and conventional tillage (CT), were assessed in a randomized complete block design with three replications. Results revealed that continuous adoption of MT+CLM had the lowest bulk density (1.31 and 1.37 Mg m−3) and maximum water holding capacity (48.49% and 43.1%) and moisture content (22.4% and 25%) at 0–10 and 10–20 cm soil layers, respectively, after 3 years. The infiltration rate (2.35 mm min−1) was also maximum under MT+CLM, followed by NT+CLM. MT+LMC had 13.8 and 27.15% higher available nitrogen and phosphorus, respectively, than CT at 0–10 cm soil depth. The MT+CLM gave a significantly higher maize grain yield (2.63 Mg ha−1), followed by NT+CLM (2.63 Mg ha−1) over the others. A cowpea green pod yield of 1.65 Mg ha−1 was also obtained from the legume coculture. Thus, the study found that live mulch of cowpea under MT/NT improved soil quality and subsequently led to greater productivity of summer maize in the Himalayan region of India.