Triticeae Genomics and Genetics, 2025, Vol.16, No.2, 92-100 http://cropscipublisher.com/index.php/tgg 93 ecological and management factors, this study aims to provide a scientific basis for high-yield wheat cultivation, while promoting efficient resource utilization and sustainable agricultural development. 2 Physiological Basis of Sowing Density and Nitrogen Interaction 2.1 Effects of plant density on canopy development and light interception When the planting density is high, the plants will form rows more quickly and the canopy will become tighter. In this way, the leaf area index (LAI) will increase, allowing more sunlight to be blocked, and the photosynthetic efficiency of the population will also be higher (Figure 1) (Zhang et al., 2021; Shi et al., 2025). However, if the density is too high, the growth of individual plants will weaken, and light will not easily reach the lower leaves, and the photosynthesis of the lower leaves will deteriorate. Finding an appropriate density can increase the number of effective tillers and ears, thereby helping to enhance the final yield (Yang et al., 2019; Zhou et al., 2024). Figure 1 Schematic diagram of the canopy stratification of winter wheat (Adopted from Shi et al., 2025) 2.2 Nitrogen's role in photosynthesis and grain filling Nitrogen is an important element in the formation of chlorophyll and directly affects the efficiency of photosynthesis. It also has a significant impact on the grain filling process (Mashiqa et al., 2022). When there is sufficient nitrogen fertilizer, the content of chlorophyll will increase, the speed of photosynthesis will accelerate, light energy will be more easily converted into nutrients, and the development of grains will also be better (Wang et al., 2024). However, excessive nitrogen fertilizer, especially when the density is high, can easily disrupt the hormones and balance within the plant, causing the filling of weak grains to slow down and the grain weight to decrease (Liu et al., 2020). 2.3 Interactive influence on biomass accumulation and partitioning Density and nitrogen fertilizer affect each other. They determine whether crops use more nutrients for growing leaves and roots or for filling and seed setting. When the density is moderate and the nitrogen fertilizer is well controlled, the roots will grow more and deeper, which can absorb more nitrogen from the soil, help accumulate
RkJQdWJsaXNoZXIy MjQ4ODYzNA==