Effects of Deficit Irrigation on Growth Characteristics and Yield Formation of Potato in Hexi Oasis Irrigation District

Abstract

To explore the optimal irrigation mode for potato in the Hexi Oasis Irrigation District, this study established different regulated deficit irrigation (RDI) treatments (full irrigation: 65%–75% FC; mild deficit: 55%–65% FC; moderate deficit: 45%–55% FC) to investigate their effects on potato growth characteristics and yield formation. Results showed that plant height and stem diameter decreased with increasing water deficit severity. Dry matter accumulation exhibited a similar trend, with the highest photosynthetic capacity observed under full irrigation (CK). The highest yield was achieved under the WD3 treatment (42,963.97 kg·ha⁻¹). In conclusion, mild water deficit during the seedling and tuber formation stages is most conducive to potato growth and yield formation in the Hexi Oasis Irrigation District, achieving water-saving and high-yield objectives.