Effects of Partial Straw Mulching on Potato Production under Different Rainfall Years in Dry-Farming Region

Abstract

Improving resource utilization efficiency is critical for achieving high yields and long-term agricultural development in arid and semi-arid settings. Using potato as the research material, a field trial was carried out from 2020 to 2022 in dryland agricultural areas of China, with two treatments of ridge planting with a furrow mulching straw pattern (SML) and flat planting without mulching (CK). The responses of the dryland potato yield, water use efficiency (WUE), and soil hydrothermal properties to the two cultivation patterns were investigated. The results indicated that during the potato reproductive period, the soil temperature of 0–25 cm in the SML treatment dropped by 0.70–0.83 °C, in comparison to CK; the ridge and furrow-covered belt, which showed a warming effect at 7:00 a.m. in the seedling stage (SD) and the budding stage (BP), was lower than CK in all the rest of the time, and also the planting belt on the ridge, which cooled down significantly at 14:00 a.m. and the performance varied between the years of 7:00 a.m. and 17:00 a.m. SML significantly decreased the water consumption before BP but significantly increased it after BP in the year of median water and mild drought, while the total amount of water consumed during the entire growing season did not differ significantly from CK’s. In the year of moderate drought, SML’s total water consumption was significantly less than that of CK, with the water consumption significantly lower before BP and after the tuber bulking stage (TB), but significantly higher from the BP to the TB. In three consecutive growing seasons, SML increased the yields by 9.72–41.67% and WUE by 4.62–11.14% compared with CK, with the yields significantly or positively connected with the average soil temperatures at the TB, the starch accumulation stage (SA), and the water consumption from the BP to the TB. Overall, partial straw mulching could be used as a cultivation technique to achieve sustainable agricultural development in dry farming areas.