蒙古沙冬青根围AM和DSE真菌与土壤因子的相关性研究

Correlation Study of AM and DSE Fungi and Soil Factors in the Rhizosphere of Ammopiptanthus mongolicus

于2012年6月对银川、沙坡头、民勤3个样地的蒙古沙冬青（Ammopiptanthus mongolicus）根围采集5个土层（0~10、10~20、20~30、30~40、40~50cm）的土样和根样,研究了蒙古沙冬青根际AM和DSE真菌空间分布以及土壤因子的生态作用,以阐明沙冬青与土壤真菌的共生关系,为利用共生真菌资源促进沙冬青生长和荒漠植被恢复提供依据。结果表明：（1）沙冬青根系能被AM和DSE真菌高度侵染,共生程度和生态分布具有明显空间异质性。（2）沙坡头样地AM真菌总定殖率最高,民勤DSE定殖率最高,但不同样地菌丝、泡囊、丛枝和定殖强度无显著差异;同一样地不同土层AM真菌总定殖率和DSE定殖率无显著差异。（3）相关性分析表明,AM真菌总定殖率与土壤速效P显著正相关;泡囊定殖率与有机质显著正相关,与速效P极显著正相关;定殖强度与总球囊霉素（TEG）显著正相关,与碱解N和速效K极显著正相关;DSE定殖率与易提取球囊霉素（EEG）极显著正相关,与碱解N显著正相关。（4）通径分析表明,土壤有机质、EEG和速效K是通过直接作用影响AM真菌总定殖率和DSE定殖率。

In order to elucidate the spatial distribution of AM and DSE fungi and ecological function of soil factors,we sampled from three different sites such as Yinchuan,Shapotou and Minqin in June 2012.Soil and root samples of Ammopiptanthus mongolicus were collected and divided into five depth intervals,0~10 cm,10~20 cm,20~30 cm,30~40 cm,and 40~50 cm,respectively.The results showed that：（1）A.mongolicus root is infected highly by AM and DSE fungi.The infection and ecological distribution of AM and DSE fungi is different between different spaces.（2）AM fungal colonization of Shapotou significantly higher than that of Minqin and Yinchuan.The highest colonization of DSE is Minqin.The hyphal,vesicular,arbuscular and total colonization of different sample plots were no significantly difference.AM fungal colonization and DSE colonization were no significantly differences in different soil layers of the same sample plot.（3）AM fungal colonization had significantly positive correlation with available P.Vesicular colonization had significantly positive correlation with organic matter,and had extremely significant positive correlation with available P.Colonization intensity was significantly positive correlation with TEG,and were extremely significant positive correlation with available N and available K.DSE had extremely significant positive correlation with EEG,and had significantly positive correlation with available N.（4）Path analysis showed that organic matter,EEG and available K directly affects the colonization of AM and DSE.The study for expound the symbiotic relationship between soil fungi with A.mongolicus,soil fungal resources to promote A.mongolicus＇ growth and the diagnosis of desert soil provides the basis.