Enhancement of wheat's adaptability to recurrent drought by improving water transport and root physiological resistance through nitrogen application and partial root-zone irrigation technology.

内容摘要

Growing crops expose to drought stress more than once, yet it remains unclear whether early-stage drought will have a warning effect on the later drought. Nitrogen supply and partial root-zone irrigation (PRI) technology are thought to improve drought resistance, but their coordinated effects on hydraulic regulation and physiological resistance under recurrent drought conditions remain uncertain. Compared to (Full irrigation) FI, both one-time drought (D1) and recurrent drought (D2) reduced biomass, root activity, root hydraulic conductance (Kr), and root water potential (RWP). However, D2 plants-maintained Kr and RWP at levels similar to D1 while exhibiting stronger antioxidant activity and osmotic adjustment, indicating improved physiological acclimation to recurrent drought. Nitrogen supplementation significantly promoted biomass accumulation, osmotic production, and hydraulic performance. PRI further enhanced water transport capacity by increasing Kr, stimulating osmotic regulation, and enhancing antioxidant capacity while reducing oxidative damage under water-deficit conditions. The coordinated regulation of nitrogen supply and PRI improves plant resilience and recovery capacity under recurrent water deficit conditions by sustaining water transport and strengthening root physiological resistance. These findings highlight the interactive role of nutrient management and irrigation strategy in enhancing plant resilience to repeated drought events.