Interactive effects of nitrogen and potassium on photosynthesis and photosynthetic nitrogen allocation of rice leaves

BMC Plant Biology

卷:19

Merle Tränkner¹  Siyuan Huang²  Tao Ren²  Wenfeng Hou²  Jianwei Lu²  Rihuan Cong²  Xiaokun Li²  Jinyao Yan² 

[1] Department of Crop Sciences, Institute of Applied Plant Nutrition (IAPN), Georg-August-University Göttingen;

[2] Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture/Microelement Research Center/College of Resources and Environment, Huazhong Agricultural University;

关键词: Nitrogen;    Potassium;    Photosynthesis;    Photosynthetic nitrogen allocation;    Photosynthetic nitrogen use efficiency;    Oryza sativa L;   

DOI  :  10.1186/s12870-019-1894-8

来源: DOAJ

【 摘 要 】

Abstract Background Nitrogen (N) and potassium (K) are two important mineral nutrients in regulating leaf photosynthesis. Studying the interactive effects of N and K on regulating N allocation and photosynthesis (Pn) of rice leaves will be of great significance for further increasing leaf Pn, photosynthetic N use efficiency (PNUE) and grain yield. We measured the gas exchange of rice leaves in a field experiment and tested different kinds of leaf N based on N morphology and function, and calculated the interactive effects of N and K on N allocation and the PNUE. Results Compared with N0 (0 kg N ha− 1) and K0 (0 kg K2O ha− 1) treatments, the Pn was increased by 17.1 and 12.2% with the supply of N and K. Compared with N0K0 (0 kg N and 0 kg K2O ha− 1), N0K120 (0 kg N and 120 kg K2O ha− 1) and N0K180 (0 kg N and 180 kg K2O ha− 1), N supply increased the absolute content of photosynthetic N (Npsn) by 15.1, 15.5 and 10.5% on average, and the storage N (Nstore) was increased by 32.7, 64.9 and 72.7% on average. The relative content of Npsn was decreased by 5.6, 12.1 and 14.5%, while that of Nstore was increased by 8.7, 27.8 and 33.8%. Supply of K promoted the transformation of Nstore to Npsn despite the leaf N content (Na) was indeed decreased. Compared with N0K0, N180K0 (180 kg N and 0 kg K2O ha− 1) and N270K0 (270 kg N and 0 kg K2O ha− 1), K supply increased the relative content of Npsn by 17.7, 8.8 and 7.3%, and decreased the relative content of Nstore by 24.2, 11.4 and 8.7% respectively. Conclusions This study indicated the mechanism that K supply decreased the Na but increased the Npsn content and then increased leaf Pn and PNUE from a new viewpoint of leaf N allocation. The supply of K promoted the transformation of Nstore to Npsn and increased the PNUE. The decreased Nstore mainly resulted from the decrease of non-protein N. Combined use of N and K could optimize leaf N allocation and maintain a high leaf Npsn content and PNUE.

【 授权许可】

Unknown