Abstract: To clarify the effects of mulching cultivation on soil temperature and yield of dryland potato fields in semi-arid region of Northwest China, a field experiment was conducted in the semi-arid agricultural region of Longzhong in 2021. There were four treatments, including straw strip mulching of single row (S30), straw strip mulching of double row (S50), plastic film mulching (PM), and open field no mulching (CK). The results showed that compared with CK, S30 and S50 reduced soil temperature at each stage of potato growth by 0.8-3.2 ℃ and 0.2-1.7 ℃, respectively, while PM significantly increased soil temperature by 1.9-3.5 ℃, with the greatest decreasing and increasing at the seedling and tuber bulking stage, respectively. Among different soil layers, the temperature under S30 and S50 decreased by 1.4-2.8 ℃ and 0.2-1.4 ℃ compared with CK, respectively, with the largest decrease in 10 cm soil layer. The temperature under PM increased by 2.3-3.3 ℃, with the largest increase in 15 cm soil layer. Straw strip mulching inhibited the loss of soil heat during the low temperature period, and hindered the absorption of heat by the surface during the high temperature period, while plastic film mulching enhanced the absorption of heat by the surface. Compared with CK, the temperature gradient of straw strip mulching decreased by 12.2-13.9 ℃·m^-1 on average, with stronger reduction of S30 than S50. The temperature gradient of plastic film mulching increased by 1.9-14.4 ℃·m^-1. Mulching significantly increased potato yield, with yield increase in an order of PM (16.1%) > S50 (14.1%) > S30 (8.4%). In Longzhong, straw strip mulching can regulate and optimize soil temperature of potato fields, promoting tuber bulking and yield formation, which is a suitable technology for potato cultivation in semi-arid areas.

Key words: straw strip mulching, plastic film mulching, soil temperature, dryland potato, yield