Impact of extended dryland crop rotation on sustained potato cultivation in Northwestern China

Sustainable agricultural development is challenged by the growing population and increasing instances of drought. Over multiple years, the continuous planting of potatoes can lead to a decrease in both potato yield and soil quality. Crop rotation proves to be a viable solution for enhancing soil productivity, especially in arid and semi-arid areas. A 5-year field experiment was conducted in northwestern China's semi-arid region to evaluate the impact of different potato rotation treatments (1-year rotation with maize, 3-year rotation with maize, oil flax and broad bean; 2-year continuous potato planting rotated with maize and 5-year continuous potato planting) and mulching techniques (unmulched and plastic film) on potato yield and soil fertility. The results showed that crop rotation (1-year and 3-year) improved plant height, dry matter accumulation, soil quality, and reduced water footprint. Under plastic film mulching mode, 1-year rotation resulted in an increase in number of potatoes per plant by 38.24%, economic benefits by 9.70%, water use efficiency by 41.86 and soil fertility in comparison to the 5-year continuous planting, the tuber yield significantly increased by 78.86%, and the green/grey/total water footprint reduced by 28.8%–46.4%. We recommend the 1-year rotational cropping system using plastic film mulch as an effective technique for addressing the challenges of continuous potato cultivation in arid and semi-arid regions.