轮作对甘薯地线虫群落组成及多样性的影响

针对甘薯茎线虫病严重的多年连种区进行轮作玉米试验,研究连种甘薯、轮作玉米对甘薯地土壤线虫群落种类组成、垂直分布、线虫群落的多样性的影响,其结果共获得3目8科15属线虫。连种甘薯地极优势属为茎属Ditylenchus,甘薯地轮作玉米其极优势属为头叶线虫属Cephalobus、真头叶线虫属Eucephalobus,滑刃Aphelenchoides和真滑刃线虫属Aphelenchus。连种甘薯和轮作玉米地同一土层线虫属数量间没有显著差异,线虫数量间有显著差异;应用Shannon多样性指数、J均匀度指数、SR丰富度指数分析了连种甘薯和轮作玉米地土壤线虫群落的多样性,其中Shannon指数、SR指数最敏感,应用WI指数分析了土壤线虫群落的营养结构,WI指数可反映轮作玉米与连种甘薯间土壤线虫群落结构的差异;轮作可减少植物寄生线虫种类和数量,增加食细菌和食真菌线虫的数量,可改变线虫群落的营养结构。

Effect of Rotate on Nematode Community Composition and Diversity in Sweet Potato Field

The effect of rotate on nematode community composition and diversity were investigated in the rotate corn and sweet potato field in Northeast of China. 3 order, 8 families and 15 category were observed. Ditylenchus, Cephalobus, Eucephalobus, Aphelenchoides, Aphelenchus was the dominant genera. There were Singificant differences between different soil layer in thel number of nematodes category during the study period, but were no significant differences in the total number of nematodes. Ecological index of diversity, index of evenness and index of richness of the nematode community were compared between the treatments and the control plot. Shannon indxs and SR indxs richness were found to be more Sensitive than other ecological indices for assessing the response of nematode communities to the application of rotate corn and sweet potato field. WI index were used to reflecting the differences between the nutrition structure of rotate corn field and succession sweet potato field. Rotate can reduce the species and number of autoecious nematode, increase number of eating bacteria and eating epiphyte nematode, can also change the nutrition structure of nematode community.