Nitrogen Use Efficiency and Adaptation of Elite Varieties of Dryland Wheat (Triticum aestivum L.) in the Loess Plateau of China

Wheat is the most widely cultivated food crop on the planet, and it feeds the majority of the world's population. The field experiment was performed from 2019 to 2021 in the eastern part of Loess Plateau, China Nitrogen (N) fertilizer application improves winter wheat yield. It was necessary to analyze the nitrogen utilization of different varieties and screen varieties with high yield and high nitrogen utilization. Six dryland wheat varieties YH-20410, YH-618, YH-805, JM-92, C-6359, and LH-6 were selected to compare the differences in nitrogen uptake and utilization yield, and quality. The aim was to provide theoretical basis for high yield, and high-efficiency wheat production in dryland of southeast loess Plateau. The results showed that the rainfall during the fallow period from 2019 to 2021 was 245.5 mm and 288.9 mm, respectively, and the nitrogen application rate was 180 kg ha-1.The highest transshipment amount, and transshipment rate of nitrogen before anther were found in YH-618, which reached 79.4 kg ha-1 and 58.6%, respectively. The yield of wheat cultivar YH-20410 was the highest, reaching 4890 kg ha-1, which was significantly higher than that of YH-805, JM-92, C-6359 and LH-6, but there was no significant difference of YH-618. The grain protein content of YH-618 was the highest (15.2%), which was not significantly different from that of JM-92, YH-805 and LH-6, but significantly higher than that of YH-20410, and C-6359, respectively. Therefore, in high-yield years, fallow cultivation can help adjust the relationship among the components, promote a reasonable distribution, and improve yield.