Variation in Leaf Type, Canopy Architecture, and Light and Nitrogen Distribution Characteristics of Two Winter Wheat (Triticum aestivum L.) Varieties with High Nitrogen-Use Efficiency

作者：Zhiyong Zhang, Sai-Jun Xu, Qiongru Wei, Yuxiu Yang, Huqiang Pan, Xinlu Fu, Zehua Fan, Butan Qin, Xiaochun Wang, Xinming Ma, Shuping Xiong · 发表于：Agronomy · 年份：2022 · DOI：10.3390/agronomy12102411 · 被引用次数：10 · 研究领域：Plant nutrient uptake and metabolism、Crop Yield and Soil Fertility、Wheat and Barley Genetics and Pathology

Studies of traits related to nitrogen (N)-use efficiency (NUE) in wheat cultivars are important for breeding N-efficient cultivars. Canopy structure has a major effect on NUE, as it determines the distribution of light and N. However, the mechanism by which canopy structure affects the distribution of light and N within the canopy remains unclear. The N-efficient winter wheat varieties YM49 and ZM27 and N-inefficient winter wheat varieties XN509 and AK58 were grown in the field under two N levels. Light transmittance was enhanced, and the leaf area index and photosynthetically active radiation were lower in the N-efficient cultivar population, which was characterized by moderately sized flag leaves, a low frequency of canopy leaf curling, a low light attenuation coefficient (KL), and high plant compactness. Reductions in the amount of shade increased the distribution of light and N resources to the middle and lower layers. The photosynthetic rate, transpiration rate, instant water-use efficiency, and canopy photosynthetic NUE were higher, N remobilization of the upper and middle canopy leaves was reduced, and the leaf N content was high in the N-efficient cultivars. A higher ratio of the N extinction coefficient (KN) to KL reflects the assimilation ability of the N-efficient winter wheat cultivars, resulting in improved canopy structure and distribution of light and N, higher 1000-grain weight and grain yield, and significantly increased light and NUE. An improved match betwe...