凤凰单丛茶园土壤线虫群落特征

Characteristics of soil nematode community in Fenghuang Dancong tea plantations

为探讨凤凰山单丛茶园土壤线虫群落特征,对4种类型茶园(古茶园、有机茶园、无公害茶园及普通茶园)土壤线虫进行了采样、分离和鉴定。结果表明:4种茶园中共鉴定到线虫19341条,分别隶属于2纲6目18科42属。古茶园Shannon指数显著低于其他3种茶园(P<0.05),有机茶园Shannon指数最高;古茶园和有机茶园土壤线虫丰富度指数和密度类群指数高于无公害茶园和普通茶园。4种茶园的土壤总线虫和类群数随土壤深度的加深呈递减分布;有机茶园中食细菌线虫和食真菌线虫数量显著高于其他茶园(P<0.05);古茶园和普通茶园植物寄生线虫成熟度指数(PPI)高于其他茶园,古茶园PPI/MI值较高,并与其他茶园存在显著差异(P<0.05),表明古茶树对土壤环境影响较大。综上所述,土壤线虫群落特征可反映不同管理方式下茶园土壤健康状况,土壤线虫可作为评价茶园土壤生态环境的重要指示生物。

To uncover the nematode resource and soil health degree in Fenghuang Dancong tea gardens, soil nematodes were sampled, isolated and identified from four types of Dancong tea gardens, including ancient tea plantation, organic tea plantation, pollution-free tea plantation and ordinary tea plantation. Results showed that a total of 19341 nematodes were identified in the four tea plantations, which belong to 2 phylum, 6 order, 18 family and 42 genera, respectively. Shannon index in the ancient tea plantation was significantly lower than in the other three tea plantations, with the highest in the organic tea plantation. Margalef richness index and Density- Groups index of nematodes in the organic tea plantation and ancient tea plantation were higher than in the other two tea plantations. Soil nematode communities displayed vertical distribution patterns in all tea plantations, and the groups and individuals of nematodes decreased with the in- crease of soil depth. Structure characteristics of nematode trophic groups showed bacteria-feeding nematodes and fungi-feeding nematodes in the organic tea plantation were significantly higher than in the other three tea plantations. The PPI index of herbivorous nematodes in the ancient tea plantation and ordinary tea plantation was higher than in the other two plantations. PPI/MI ratio was significantly higher in the ancient tea plantation than in the other three plantations, sugges- ting that the ancient tea trees had significant disturbance to soil environment. In conclusion, the characteristics of soil nematode community can effectively reflect the health status of tea garden soil, which can be an important biological indicator for ecological environment assessment of tea garden soil.