[Silkworm excrement organic fertilizer: its nutrient properties and application effect].

In this paper, silkworm excrement was harmless-treated via controlled fermentation to prepare silkworm excrement organic fertilizer (SEOF). The nutrient properties of the SEOF were determined, and a pot experiment was conducted to examine the application effect of the fertilizer. After fermentation, the total N, P, and K contents in the SEOF had a significant increase, being 58.0%, 84.4% , and 29.7% higher than those in the raw material, respectively. The addition of microbial inoculants shortened the fermentation period, and decreased the carbon and nitrogen losses during fermentation. With the application of SEOF, the seed germination index of cabbage and tomato was higher than 80% , suggesting that the fertilizer had no inhibitory effect on the seed germination. The application of SEOF not only increased the Chinese cabbage yield and its nutrients and Vc contents, decreased the plant nitrate content, but also improved the soil pH value, and increased the soil available nutrients and organic matter contents and soil enzyme activities, with better effect than applying composted goat feces.