Abstract:

In order to comprehensively evaluate the effects of bio-fertilizer on soil improvement and crop growth, the responses of soil nematode community structure at different soil depths under different bio-fertilizer schemes were studied. Four kinds of foliar fertilizers, including wood vinegar, homemade fermented bio-extracts, the mixture of the two and clean water, were used as test materials. Five-point sampling method was used to collect soil at 0-5 cm and 5-10 cm soil layers, and the diversity index of nematode community was measured. The results showed that both homemade fermented bio-extracts and wood vinegar promoted relative abundance of predatory/omnivorous nematodes by 37% and 210% compared with control. Homemade fermented bio-extracts caused plant-parasite nematodes migration downward, and the relative abundance in shallow and deep soil layers were 29% and 64%, respectively. All the homemade fermented bio-extracts, wood vinegar and the mixture induced predatory/omnivorous nematodes migration upward, and the relative abundance in the shallow and deep soil layers were 65% and 18%, 43% and 21%, and 48% and 5%, respectively. Homemade fermented bio-extracts, wood vinegar and the mixed solution all induced plant-parasite nematodes migration downward and predatory/omnivorous nematodes migration upward. Both homemade fermented bio-extracts and wood vinegar could promote the relative abundance of predatory/omnivorous nematodes, and could inhibit and repel plant-parasite nematodes.

Key words: soil nematodes, homemade fermented bio-extracts, diversity, wood vinegar, community structure