Abstract:

To study the effects of different levels of organic fertilizer on wheat yield and soil fertility, a field plot experiment was conducted in Fangshan, Beijing. We set up 6 treatments, which were blank control (CK), application of 0.5 times organic fertilizer (0.5 ON), application of organic fertilizer with equal nitrogen amount of conventional fertilization (ON), application of 1.5 times organic fertilizer (1.5 ON), application of 2 times organic fertilizer (2 ON), and application of 3 times organic fertilizer (3 ON). Long-term positioning test results showed that the yield of wheat treated with 3 times organic fertilizer (3 ON) was the highest, and was at a relatively high level in the past 5 years, which had the greatest impact on the number of ears, grains per panicle and 1000-grain weight per hectare. The application of organic fertilizer significantly increased soil organic matter, available nitrogen, phosphorus, potassium and microbial biomass. Among all the treatments, the application of 1.5 ON and 3 ON had the most obvious effects on soil organic matter, total nitrogen and available phosphorus. The application of different levels of organic fertilizer could increase the soil microbial carbon and urease content. The effect of 1.5 ON treatment on urease content was the most significant, the effect of 3 ON treatment on soil microbial carbon was the most significant, and the application of different levels of organic fertilizer could increase the ratio of 0.01-0.05 mm particle size. The study shows that 3 ON treatment is worth popularizing in wheat production.

Key words: organic fertilizer, wheat yield, fertilized soil, microbial carbon, different levels