To explore the effects of increasing different types of bacterial agents fertilizers on wheat aphids and, powdery mildew, photosynthetic characteristiss and yield under the reduction of seed coating agents, the wheat aphid low-susceptible variety Chuanmai 104 and high-susceptible variety Neimai 836 were used as experimental materials. Field experiments were conducted to study the effects of photosynthetic bacteria, microbial agents, silicon fertilizer or potassium dihydrogen phosphate on soil enzyme activity, plant photosynthetic characteristics, wheat disease and pest control, and yield traits in wheat fields under 20% reduction of seed coating agents. The results showed that compared with the conventional dosage of seed coating agent, the application of microbial agents after reducing the dosage of seed coating agent by 20% significantly increased the urease activity of Chuanmai 104, and the catalase and cellulase activities of Neimai 836 in the rhizosphere soil at booting stage. At booting and heading stages, the number of wheat aphids in the low-susceptible cultivar Chuanmai 104 was significantly lower than that in Neimai 836. The application of microbial agent and silicon fertilizer significantly reduced the occurrence of wheat aphid and powdery mildew, and the control effect of aphid and powdery mildew was 8.0 and 10.2 percentage points higher than that of conventional agent. The combination of photosynthetic bacteria, microbial agents, silicon fertilizer or potassium dihydrogen phosphate and other agronomic measures effectively increased the nitrogen content and SPAD value of wheat flag leaves to improve the photosynthetic efficiency of leaves. Among them, the yield of Chuanmai 104 and Neimai 836 under the application of silicon fertilizer was the highest and significantly increased by 16.0% and 18.2%, respectively, compared with the conventional seed coating agent treatment. The above results showed that the amount of seed coating agent can be reduced by applying silicon fertilizer or microbial agent after wheat seed coating. In addition, it can also effectively improve soil enzyme activity, reduce the occurrence of aphids and powdery mildew, improve leaf photosynthetic characteristics, and increase wheat yield. |