广西南宁市武鸣区香蕉根际土壤丛枝菌根真菌资源初探

Initial Exploration of Arbuscular Mycorrhizal Fungi in Banana Fields of Wuming,Guangxi

【目的】探明广西南宁市武鸣区香蕉根际土壤丛枝菌根(AM)真菌分布状况,为广西香蕉AM真菌资源收集和开发利用提供参考。【方法】采集健康和患枯萎病香蕉植株根际5～20 cm土样,采用湿筛倾析—蔗糖离心法分离根际土壤AM真菌孢子,形态学方法进行AM真菌种属鉴定。【结果】供试土样共鉴定出6种类型AM真菌孢子,其中球囊霉属2种,无梗囊霉属4种。健康土样的AM真菌孢子密度明显高于病土,两种土样的共有种为双网无梗囊霉、细凹无梗囊霉和空洞无梗囊霉。健康土样的AM优势特有种为地表球囊霉,病土的特有种为长孢球囊霉和疣状无梗囊霉,但未见优势种。【结论】供试土样的AM真菌类型主要为球囊霉属和无梗囊霉属。健康土样的优势AM真菌在提高香蕉植株抗枯萎病性能方面很可能扮演重要角色。

【Objective】To provide fundamental references for resource collection and utilization of AM fungal strains,the distribution of AM fungi in rhizospheric soil of Wuming banana planting areas in Guangxi was investigated.【Method】The soil samples(5-20 cm)were collected from the rhizosphere of the healthy and fusarium wilt banana plants,respectively.AM fungal spores were screened using wetting sieve decantation and sucrose centrifugation method,and identified on the basis of morphological characteristics.【Result】Six species of AM fungi were identified in the soil samples,including 2 species of Glomus and 4 species of Acaulospora.Density of AM spores in the healthy rhizospheric soils were significantly higher than that infected by fusarium wilt.Acaulospora biretichlata,Acaulospora Scrobiculata and Acaulospora cavernata were found in soils from both the healthy and infected banana plants.Glomus versiforme was the dominant and specific specie of AM in the healthy soil samples.Glomus dolichosporum and Acaulospora tuberculata were specific species and there was no dominant species in the soils samples with fusarium wilt.【Conclusion】Glomus and Acaulospora were dominant in the soil samples around banana rhizosphere in Wuming,.The ascendant AM fungi from healthy soil samples are likely to play an important role in improving the resistance against fusarium wilt in banana plantation.