黄芩根围AM真菌分布与土壤碳氮相关性研究

Relationship between distribution of AM fungi in the rhizosphere of Scutellaria baicalensis and soil C and N

为探讨丛枝菌根(AM)真菌分布与土壤碳氮含量动态变化之间的关系,于2010年6-10月每月分别从河北省安国市中药材种植基地、霍庄和常庄黄芩(Scutellaria baicalensis)种植地采集土壤样品,分析测定了黄芩根围AM真菌各结构定殖率、孢子密度、球囊霉素和土壤碳氮含量。结果表明:黄芩根系能与AM真菌形成良好的中间型(Intermediate-type)菌根共生联合体,平均总定殖率80.8%,平均孢子密度3 571个/(100 g土)。AM真菌定殖率和孢子密度与采样时间密切相关,最大孢子密度和最高总定殖率均出现在10月。线性回归方程表明,AM真菌代谢产物总球囊霉素和易提取球囊霉素均与土壤有机碳和全氮呈显著线性相关关系。总球囊霉素中碳和氮含量占土壤有机碳和全氮的平均百分比分别为4.8%和16.3%,说明球囊霉素是土壤碳氮的重要来源,可作为黄芩根围土壤有机碳和全氮动态变化的检测和评价指标。

In order to investigate the relationship between distribution of AM fungi in the rhizosphere of chinese traditional medicinal herbs and the dynamic change of soil C and N,the rhizosphere soil and roots samples of Scutellaria baicalensis were collected in Jidi,Huozhuang and Changzhuang of Anguo city in Hebei monthly,from June to October,2010.The colonization and spore density of AM fungi and the content of glomalin and soil C,N in the rhizosphere of Scutellaria baicalensis were determined.The results showed that a good Intermediate-type mycorrhiza can be formed between AM fungi and Scutellaria baicalensis.The average spore density and total colonization of AM fungi was 3 571 No./100 g and 80.8%,respectively.The colonization and spore density of AM fungi closely related with the sampling time,the highest colonization and the maximum spore density appeared in October.The results of linear regression equation showed that soil organic C and total N had a significantly correlation with easily extractable glomalin（EEG） and total glomalin（TG）.The C content of TG accounted for averagely 4.8% of soil organic C and the N content of TG accounted for averagely 16.3% of soil total N,which showed that glomalin was an important resource of soil C and N.Glomalin content can be used as an effective evaluation for the dynamic change of soil C and N in the rhizosphere of Scutellaria baicalensis.