Abstract: We investigated the effects of corn stover mulching amount on plant-parasitic nematode communities after 11-year stover mulching in the long-term Conservation Tillage Research and Development Station of the Chinese Academy of Sciences. Four treatments, including no corn stover mulching (NT0), 33% (NT33), 67% (NT67) and 100% (NT100) mulching amount of total corn stover harvest amount were set up. A total of 16 plant-parasitic nematode genera were identified, including four dominant genera, Basiria, Tylenchus, Pararotylenchus, and Pratylenchus. Our results showed that the total abundance of plant-parasitic nematodes firstly increased and then decreased in the 0-10 cm soil layer with the increases of corn stover mulching amount, while no obvious trend was found in the 10-20 cm soil layer. There was no significant variation in the total plant-parasites among different treatments in both soil layers. Among c-p (colonizers-persisters) groups, c-p3 of plant-parasitic nematodes was the dominant group. Corn stover mulching increased the total organic carbon content in the 0-10 cm soil layer, the abundance of dominant genera of Basiria and Tylenchus, the relative bundance of c-p2 group, and the biomass of c-p2 and c-p3 groups in the 0-10 cm soil layer. The increases of corn stover mulching amount did not enhance the possibility of harm from plant-parasitic nematodes. Stover return influenced the c-p groups of plant-parasitic nematodes through affecting soil organic carbon and pH.

Key words: TOC, POC, SMBC, controlled traffic farming, oasis irrigation area.