Higher Seed Rates Enlarge the Effects of Wide-Belt Sowing on Root Length Density, Thereby Improving Nitrogen Uptake and Use Efficiencies in Winter Wheat

• Published in: Plants (Basel) Vol. 13; no. 17; p. 2476
• Main Authors: Wang, Yuechao, Li, Wen, Deng, Yaoyao, Xue, Jianfu, Gao, Zhiqiang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.09.2024
• Subjects: Agricultural production; Comparative analysis; Density; Efficiency; Environmental aspects; Grain; Growing season; Measurement; Methods; Nitrogen; Nitrogen in the body; nitrogen uptake; nitrogen use efficiency; Physiological aspects; Planting; Protein transport; Proteins; root length density; Seasons; seed rate; Seeds; Sowing; Testing; Translocation; Wheat; wide-belt sowing; Winter; Winter wheat; China; Canada; Germany; seed rate; wide-belt sowing; root length density; nitrogen use efficiency; nitrogen uptake
• ISSN: 2223-7747; 2223-7747
• DOI: 10.3390/plants13172476

The optimized sowing method and appropriate seed rate can improve wheat N use efficiency. However, the interactive effect of the sowing method and seed rate on N use efficiency, particularly N uptake and root length density, are unclear. A field experiment was conducted for two growing seasons in southern Shanxi province, China, using a split-plot design with the sowing method as the main plot (wide-belt sowing, WBS, and conventional narrow-drill sowing, NDS) and seed rate as the sub-plot (100-700 m ). Our results showed that WBS had a significant and positive effect on N use efficiency (yield per unit of available N from the fertilizer and soil, by 4.7-15.4%), and the relatively higher seed rates (>300 or 400 m ) enlarged the effects. The N use efficiency increases under WBS were mainly attributed to the increases in N uptake before anthesis, resulting from the promoted nodal roots per plant and per unit area, and root length density in the top layer(s). WBS promoted N translocation and the N harvest index, resulting in equivalent grain protein concentration and processing quality compared to NDS. Thus, adopting higher seed rates (>300 m ) combined with WBS is recommended for achieving greater N efficiencies while maintaining the grain protein concentration and processing quality of winter wheat.