Enhancing the yield, quality, and potassium use efficiency of direct-seeded hybrid indica rice through wheat-straw returning combined with potassium fertilizer application

Yuanyuan Sun; Xinghai Huang; Ruijie Li; Tao Lu; Ailing Wang; Mingming Hu; Jiarui Ni; Yong Zhao; Lin Feng; Qin Liao; Zhonglin Wang; Zhiyuan Yang; Jun Ma; Yongjian Sun

Frontiers in Plant Science, Vol. 17, Article number: 1839324 (2026), May 2026 (IF=4.800).

Abstract

Introduction The synergistic effects of wheat-straw returning and optimized K fertilization on yield, quality, and KUE of direct-seeded rice in rice–wheat rotation systems remain poorly understood. Methods A two-factor field experiment was conducted using super hybrid indica rice Fyou 498, with two straw treatments (M0, no returning; M1, returning) crossed with five K rates (0, 62.5, 125, 187.5, and 250 kg K ha⁻¹). Results M1 significantly increased photosynthetic potential by 1.83%–22.34%, postheading dry matter accumulation by 2.06%–36.56%, and yield by 1.06%–14.36% compared with M0. Under M1 combined with 125 kg K ha⁻¹, yield improved by 4.79%–19.95%, KUE increased by 3.61–15.15 kg kg⁻¹, grain chalkiness reduced by 0.03%–2.97%, taste value increased by 0.64–5.14, and soil K depletion was reduced by 39.25–52.13 kg ha⁻¹. Discussion Wheat-straw incorporation combined with 125 kg K ha⁻¹ represents a promising approach for synergistic improvements in grain yield, rice quality, resource-use efficiency, and economic benefits.