广西东南沿海蔗区根际土壤AM真菌多样性研究

Diversity of arbuscular mycorrhizal fungi in sugarcane fields of Southeastern Guangxi

【目的】探明广西东南沿海甘蔗种植区北海和钦州两地甘蔗根际土壤中从枝菌根真菌（AM真菌）的分布状况,为广西甘蔗AM真菌资源保护和优势菌株的筛选及开发利用提供参考。【方法】采集蔗区甘蔗根际5~20cm土样,采用湿筛倾析-蔗糖离心法分离AM真菌孢子,根据形态结构鉴定孢子种属。【结果】分离出6种类型AM真菌孢子,其中球囊霉属两个类型,无梗囊霉属3个类型,盾巨孢囊霉属1个类型。【结论】供试蔗区根际土壤AM真菌群落中,无梗囊霉和球囊霉属占优势,A.sp1在两地蔗区出现数量最多,为共有种,两地蔗区特有种：钦州为未定种A.sp2,北海为S.gregaria。

[Objective]Distribution of arbuscular mycorrhizas （AM） fungi in rhizospheric soils of Beihai and Qinzhou sugarcane planting areas in Southeast Guangxi was investigated in order to provide fundamental references for mycorrhizal fungi resource conservation, and the selection and utilization of elite bacterial strains. [Method]The soil samples（5-20 cm）of rhizosphere were collected from Beihai and Qinzhou sugarcane fields, AM fungal spores were separated using wetting sieve decantation and sucrose centrifugation method, and identified on the basis of morphological characteristics of the species. [Result] Six spore species of AM fungi including 2 of Glomus, 3 of Acaulospora and 1 of Scutellospora were identified in the soil samples. [Conclusion] Among arbuscular mycorrhizas population in experimental sugarcane rhizospheric soils of Southeast Guangxi, Acaulospora and Glomus are in the ascendant. The strain A.sp1 presents the maximum in both of two sugarcane planting areas, and the special species of AM in Qinzhou and Beihai is A.sp2 and S. gregaria, respectively.