Difference Analysis of Yield and Nitrogen Use Characteristics of Different Wheat Varieties

The objective of this study was to investigate the nitrogen use efficiency of various wheat varieties and to establish evaluation indicators for nitrogen efficient use in wheat, thereby providing both theoretical reference and a practical basis. The experiment was conducted at Jiaozhou Modern Agriculture Demonstration Park of Qingdao Agricultural University (35.53°N, 119.58°E) from October 2021 to June 2023. Twenty-six main wheat varieties in the North China Plain were used as test materials. Four nitrogen fertilizer levels of 0, 150, 210, and 270 kg/hm² were set up. The nitrogen fertilizer level was the main factor, and the variety was the secondary factor. According to the yield and nitrogen accumulation of each variety under different nitrogen fertilizer levels, cluster analysis was carried out, respectively. It was found that Zhongmai 578 (H1), Zhongmai 175 (H2), and Weimai 8 (H3) had a higher yield under four nitrogen fertilizer levels. These varieties were nitrogen efficient, and their nitrogen accumulation was also higher. On the other hand, Jingshuang 16 (L1), Nongda 212 (L2), and Beijing 841 (L3) had lower yields under four nitrogen fertilizer levels. These varieties were nitrogen inefficient, and their nitrogen accumulation was also lower. The other 20 varieties had a medium yield and medium nitrogen accumulation. In this study, the differences of nitrogen use efficiency, nitrogen harvest index, nitrogen agronomic efficiency, and nitrogen partial factor productivity between three nitrogen efficient varieties and three nitrogen inefficient varieties were analyzed.