Effects of Amendment with Various Vermicomposts on the Soil Fertility, Growth of Brassica chinensis L., and Resistance of Spodoptera litura Fabricius larvae

Abstract

Amendments with vermicomposts can reduce the incidence of pests. In this study, earthworms were fed different foods to produce four vermicomposts. A pot experiment was then conducted to assess different vermicomposts’ effects on soil fertility, and the secondary metabolite content and antioxidant capacity of Brassica chinensis L., and on the growth of Spodoptera litura larvae. The results showed that the characteristics of vermicomposts are mainly affected by food supplements, and that the application of vermicomposts can improve soil fertility, whereas increasing the soil and leaf sulfur content can decrease the relative growth rate of S. litura larvae. However, there were no significant differences in the total phenolic content (TPC), total flavonoid content (TFC), nor the DPPH free radical scavenging ability under the different treatments.