Effect of plastic film mulch and irrigation water regimes on soil temperature pattern, plant growth and water productivity of maize

In arid and semi-arid climate, combining different plastic film mulches and irrigation water regimes may be lead to enhance of grain yield and water use efficiency (WUE) with water saving. For the optimum grain yield of maize crop, soil water content and temperature, and irrigation water use efficiency are still not well understood in the climate of Sindh, Pakistan. Therefore, the aim of this study was to examine the soil moisture pattern, soil temperature, yield and WUE under interaction of mulching and soil water status. This field experiment was conducted at the station of department of Irrigation and Drainage during cropping seasons 2021–22. In field trial involved three mulching modes (black and white film, without film) and two irrigation water regimes (sufficiently and severely water stress). The results showed that across the irrigation water regimes treatments, without mulched treatment plants depressed both moisture status and temperature of the soil, nonetheless, the decrease soil water status was more pronounced compared with the reduction in soil temperature. Plant dry biomass was improved when mulching with black plastic film as exemplified by the increased plant height, indicating the increased plant biomass. However, across the mulching treatments, by improving the plant micro-climate condition by black colored plastic film mulching increased significantly grain yield by 17–47% and WUE by 16–46% because less soil water depletion as compared with white plastic mulch and without mulch treatments, respectively, causing the serious waste of water resources. Across the water regimes, sufficiently water stressed condition (80% of soil water holding capacity, SWHC) could significantly enhance grain yield by 17.4% and WUE by 8% as compared to moderately water stressed condition (50% of SWHC). Mulching with black colored plastic film is suggested for maize in terms of high grain yield and water use efficiency with a minor dry biomass reduction.