Stem characteristics and yield of wheat is regulated to improve planting efficiency and reduce lodging risk by fertilizer rate and irrigation stage

Optimizing fertilizer and water application and using standardized and clean production methods are important for achieving green and sustainable agricultural development. The study was conducted from 2018 to 2021, arranged in a split-plot experimental design. Three fertilization levels (main plots) and four supplementary irrigation treatments (secondary plots) were set through three consecutive years of field positioning experiments. Chemical compound fertilizer application levels were 750 kg ha(-1) (F1), 600 kg ha(-1) (F2), 450 kg ha(-1) (F3). Irrigation levels were as follows: no irrigation during the whole growth period after emergence (W0), irrigation only at jointing stage (W1), irrigation at jointing and anthesis stage (W2), irrigation at greening, jointing and anthesis stage (W3). The results indicated that the stem length of the base increased with the increase of irrigation and water and fertilizer, especially on the base stem node. There was a significant interaction between different fertilizer and water treatments. Correlation analysis revealed a significant negative correlation between stem strength and the stem lodging index. After anthesis, the lodging index was significantly lower in the F2 treatment than that in the F1 treatment. Moreover, the contribution of dry matter accumulation to the grain before anthesis was significantly higher under the W2 treatment than that under the W3 treatment but was significantly lower than that under the W0 treatment. Furthermore, the W2 treatment exhibited significantly greater fertilizer and water effects than those under the W3 treatment, irrigation benefit increased by 10.39 kg ha(-1) mm(-1), whereas the F2 treatment exhibited significantly greater effects than those of the F1 treatment. In terms of yield, grain yield of F2W2 treatment was significantly higher than that of F3W1 treatment. The maximum yield of F2W2 treatment over three years was 9900.05 kg ha(-1). Therefore, reducing the amount of fertilizer and adjusting the irrigation regimes can enhance wheat growth and yield and mitigate the risk of lodging in the field.