荒漠环境柠条锦鸡儿AM真菌空间分布

Spatial distribution of arbuscular mycorrhizal fungi of Caragana korshinskii in desert environment

为充分利用AM真菌资源,对陕西省榆林市沙生植物园、鄂尔多斯生态研究站和宁夏回族自治区沙坡头3个不同生态条件下柠条锦鸡儿(Caragana korshinskii)AM真菌空间分布进行了研究。结果表明,柠条锦鸡儿菌根类型为I-型(Intermediate type),泡囊形态多样,形成于细胞间或细胞内,丛枝结构包括树枝状和花椰菜状2种类型。在形成丛枝菌根的同时,柠条锦鸡儿根部也能普遍被暗色有隔内生真菌感染。AM真菌定殖率和孢子密度与样地生态条件密切相关。最大孢子密度发生在0～10 cm土层,并随土层加深呈下降趋势,孢子密度与土壤速效N、有机质、脲酶和蛋白酶呈极显著正相关,泡囊定殖率与速效P含量呈显著正相关,丛枝定殖率与土壤pH呈显著正相关。孢子密度、泡囊和丛枝定殖率可作为检测土壤环境状况的指标。

The arbuscular mycorrhizal type and AM fungal ecolog skinskii in three representative sites of Shaanxi Yulin Rare Sandy dos sandy land ecological station and Ningxia Shapotou were stud cal distribution of Caragana korplants conversation field, the Ored. The results showed that mycorrhizal type was intermediate type and vesicluar in intercellular and intracellular with morphological variety. The structure of arbuscular included tree and cauliflower-shaped. The roots of C. korshinskii were also infected with dark septate endophytic fungi. Different sample sites had significantly affected spore density and the percentage of colonization of vesicle and arbuscule of AM fungi. The spore density at 0 - 10 cm depth was maximal and decreased with soil depth. There existed significant positive correlation with soil available N, organic matter, urease and proteinase. There existed significant positive correlation between vesicular colonization and soil P. There existed signifi- cant positive correlation between arbuscular colonization and soil pH. The results suggested that spore density, vesicular and arbuscular colonization were useful indictors for microcosmic monitoring and evaluating soil environment.