Straw mulch with limited drip irrigation influenced soil microclimate in improving tuber yield and water productivity of potato in subtropical India

Water-saving production technologies are essential for increasing agricultural production under limiting water resources in future periods. Potato, the underground crop needs efficient soil and water management for production sustainability. Field experiments were conducted during the dry season of 2018-19 and 2019-20 to study the effect of rice straw mulch with drip irrigation on soil temperature and moisture content and thereby its effect on the potato yield and water productivity in subtropical India. Potato was grown with two levels of soil management (straw mulch and non-mulch) and four levels of water management, i.e., conventional furrow irrigation and drip irrigation up to full field capacity (100%FC), 90%FC, and 80% FC. The results stated that the straw mulch increased the soil temperature by 0.22-0.90 degrees C compared to non-mulch plots and the maximum increase was when the air temperature was lowest during the growing period. The straw mulch also increased the soil moisture content (+3.6%) and lowered evapotranspiration (9-14%) compared to the non-mulch. Similar to mulching, the limited drip irrigation (90%FC) increased the soil temperature by >= 2 degrees C as compared to furrow irrigation. The straw mulching effectively increased the tuber yield (+15%) under limited drip irrigation with 90%FC, but not in conventional irrigation. Integration of mulching with limited drip irrigation saved 42-58% irrigation water compared to conventional furrow irrigation without mulch. Straw mulching in drip-irrigated treatments significantly increased the water productivity (30-39%) compared to non-mulch. This study provides a reference point for policymakers that drip irrigation with straw mulch can be a feasible adaptation strategy for increasing potato production in subtropical locations under resource-limited environment.