关键词: 花生, 品质类型, 施氮量, 产量, 品质, 精准施氮

Abstract: To clarify the differentiated nitrogen fertilizer application recommendation standards for the main peanut varieties with different quality types in Henan Province，this study utilized the high⁃oil peanut variety Yuanza 9102（YZ9102），the high⁃protein peanut variety Zhuhua No. 2（ZH2），and the common peanut variety Yuhua 23（YH23），which are widely promoted in Henan Province，as experimental materials. A field experiment was conducted with five nitrogen application gradients（pure N at 0，75，150，225，and 300 kg/ha）. Pod yield and its components，grain protein content and oil content，as well as the activities of key metabolic enzymes involved in fatty acid and protein synthesis in grains were investigated and measured. Linear⁃plateau model and quadratic regression model were employed for fitting analysis. The results indicated that there were significant differences in the responses of different quality⁃type peanuts to nitrogen fertilizer. In the nitrogen application range of 0—150 kg/ha，peanut pod yield increased with the increase of nitrogen application rate. YH23 had the highest yield increase of 34.6% compared to the no⁃nitrogen application，which was mainly attributed to the simultaneous increase in pod number per plant and 100⁃pod weight. ZH2 and YZ9102 showed yield increases of 26. 6% and 16. 9%，respectively，which were mainly dependent on the increase in pod number per plant. ZH2 exhibited relatively high activities of nitrogen metabolism enzymes，and its protein content gradually increased within the nitrogen application range of 0—300 kg/ha.YZ9102 showed generally high activities of fatty acid synthesis⁃related enzymes，and its oil yield gradually increased within the nitrogen application range of 0—225 kg/ha.The two models demonstrated good fitting effects on pod yield，protein yield，and oil yield.Among them，the linear⁃plateau model significantly reduced the recommended nitrogen application rate while ensuring increases in both yield and quality，offering superior economic benefits.Therefore，based on the recommended nitrogen application rates predicted by the linear⁃plateau model，differentiated nitrogen application recommendations are proposed as follows：for oil⁃use peanut variety YZ9102，the recommended nitrogen application rate is 161.7 kg/ha；for high⁃protein peanut variety ZH2，it is 201.5 kg/ha；and for common peanut variety YH23，it is 163.4 kg/ha.

Key words: Peanut, Quality type, Nitrogen application rate, Yield, Quality, Precise nitrogen application