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宁夏枸杞具有很高的药用价值和营养价值,在宁夏大面积种植,带来了巨大的经济效益.研究不同条件下宁夏枸杞根际土壤线虫群落特征,对防止枸杞园土壤退化具有重要意义.以宁夏枸杞之乡——中宁为研究区,系统分析了季节、树龄和土层对枸杞根际土壤线虫数量和生态指数的影响.结果表明:夏季宁夏枸杞根际土壤线虫数量最多,小杆属和拟丽突属为优势属;春季线虫数量最少,小杆属、针属和盘旋属为优势属;从春季到秋季,线虫稀有属种类和个体密度逐渐减少.随着树龄的增加,夏季根际土壤线虫总数逐渐减少;春季和秋季枸杞根际线虫总数先增加后减少,其中9年树龄根际土壤线虫总数最多.各树龄根际均为食细菌线虫所占比例最大,食真菌线虫和捕食-杂食类线虫比例很小,树龄<3年和>9年时植物寄生线虫比例相对较大.夏季枸杞根际20~40 cm比0~20 cm土壤线虫数量增加49.4%.随着树龄的增加,枸杞根际土壤线虫多样性指数、均匀度指数和丰富度指数均呈减小-增大-减小的趋势,而优势度指数先减小后增大.土壤p H值与土壤线虫优势度指数呈显著正相关;土壤有机质和速效磷与植物寄生线虫分别呈显著正相关和负相关;土壤碱解氮与线虫总数呈显著正相关;速效钾与线虫多个生态指数均呈显著负相关.整体上,随着树龄的增加,春季和秋季土壤线虫数量先增加后减少,夏季土壤线虫数量呈逐渐减少的趋势;线虫多样性下降,土壤逐渐退化.此外,在幼林和树龄>9年后需要抑制土壤植物寄生线虫的繁殖,以减少后期因线虫引起的病害.
Ningxia wolfberry has high medicinal value and nutritional value, planting large areas in Ningxia, brought huge economic benefits.Under different conditions, Ningxia wolfberry rhizosphere soil nematode community characteristics, to prevent the wolfberry garden soil degradation is of great significance. Ningxia wolfberry town - Zhongning as the research area, systematically analyzed the seasonal, age and soil layers of Lycium rhizosphere soil nematode number and ecological index.The results showed that: summer Ningxia Lycium rhizosphere soil nematodes the most, The genus and parachute belonged to the dominant genus. The number of nematodes was the least in spring, and the genus Pinus, Pinus and Circus belonged to the dominant genus. From spring to autumn, the species and individual density of the genus Rare Species decreased gradually. With the increase of the tree age, The total number of soil nematodes in rhizosphere decreased gradually, and the total number of rhizosphere nematode increased firstly and then decreased in spring and autumn, and the total number of soil nematodes was the highest at 9 years old. The predation-omnivore nematodes were very small, and the proportion of parasitic nematodes was relatively large at the age of <3 years and> 9 years. The numbers of parasitic nematodes increased from 20 cm to 40 cm in summer than in 0-20 cm 9.4% .With the increase of the age, the diversity index, evenness index and richness index of Lycium rhizosphere soil nematode decreased, increased and decreased, while the dominance index firstly decreased and then increased. p H and soil nematode dominance index showed a significant positive correlation; soil organic matter and available phosphorus and plant parasitic nematodes were significantly positive correlation and negative correlation; Soil alkalophilic nitrogen and nematode was significantly positive correlation; available potassium and nematodes multiple The number of soil nematodes increased first and then decreased with the increase of tree age, the number of soil nematodes decreased gradually in summer, the diversity of nematodes decreased, and the soil gradually degenerated.At the same time, Young plantations and age> Nine years after the need to inhibit soil plant parasitic nematode reproduction, in order to reduce late diseases caused by nematodes.