关键词: 嫁接, 非结构性碳水化合物, 缺氮, 光合作用

Abstract: 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 increase 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, suggesting 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.

Key words: non-structural carbohydrate., graft, nitrogen deficiency, photosynthesis