High Potassium Application Rate Increased Grain Yield of Shading-Stressed Winter Wheat by Improving Photosynthesis and Photosynthate Translocation

Yi Wang; Zhongkui Zhang; Yuanyuan Liang; Yulong Han; Yanlai Han; Jinfang Tan

doi:10.3389/fpls.2020.00134

High Potassium Application Rate Increased Grain Yield of Shading-Stressed Winter Wheat by Improving Photosynthesis and Photosynthate Translocation

Front Plant Sci. 2020 Feb 28:11:134. doi: 10.3389/fpls.2020.00134. eCollection 2020.

Authors

Yi Wang^{1

2

3}, Zhongkui Zhang¹, Yuanyuan Liang¹, Yulong Han¹, Yanlai Han^{1

2

3}, Jinfang Tan^{1

2

3}

Affiliations

¹ College of Resources and Environment, Henan Agricultural University, Zhengzhou, China.
² State Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou, China.
³ Collaborative Innovation Center of Henan Grain Crops, Henan Agricultural University, Zhengzhou, China.

Abstract

Wheat (Triticum aestivum L) production on the Huang-Huai Plain of China has substantially affected in the past 50 years as a result of the decreasing total solar radiation and sunshine hours. Potassium has a significant effect on improving leaf photosynthesis ability under stress conditions. Five potassium application rates (K), 0 (K0), 50 (K50), 100 (K100), 150 (K150), and 250 (K250) mg K₂O kg^-1 soil, combined with two shading levels, no shading (NS) and shading at early filling stage for 10 days (SE), were used to investigate the effects of K application on winter wheat growth under SE condition. Under NS condition, the parameters related to chlorophyll fluorescence characteristics, dry matter productivity and grain yields reached the maximum values at a middle K application rate (100 mg K₂O kg^-1 soil). Shading stress significantly reduced leaf SPAD value, showed negative effects on chlorophyll fluorescence characteristics and reduced grain yield of winter wheat. However, as the result of the interaction of K×S, compared to NS condition, higher K application rate (150 mg and 250 K₂O kg^-1 soil) was beneficial in terms of achieving a higher grain yield of winter wheat under SE by improving leaf SPAD value, alleviating the damage of SE on the winter wheat photosynthetic system, and increasing fructan content and dry matter translocation percentage.

Keywords: chlorophyll fluorescence characteristics; dry matter translocation amount; grain yield; potassium application rate; shading stress.