免费文献传递   相关文献

Preliminary Research on Arbuscular Mycorrhizal Fungi of Dipterocarpaceae in Xishuangbanna,Southern Yunnan

西双版纳地区龙脑香科植物AM真菌的初步研究


对云南省西双版纳地区17种龙脑香科树种根系丛枝菌根(Arbuscular mycorrhiza, AM)真菌的定居情况进行了调查,并对根围土壤中AM真菌进行了分离和鉴定。结果表明,调查根样均有不同程度的菌根感染,感染率最高可达40%,调查揭示了西双版纳地区龙脑香科植物在自然条件下可形成丛枝菌根。初步从龙脑香科植物根际土壤中分离、鉴定出32种AM真菌,隶属于无梗囊霉属(Acaulospora)、球囊霉属(Glomus)、原囊霉属(Achaeospora)、拟球囊霉属(Paraglomus)和盾巨孢囊霉属(Scutellospora),其中,无梗囊霉属和球囊霉属真菌为西双版纳地区龙脑香科植物AM真菌优势类群。

In order to investigate the status of arbuscular mycorrhizae (AM) in

 

tropical dipterocarpaceae forest, rhizospheric soil with roots of seventeen species

of dipterocarpaceae plants grown in both native forests and plantations in tropical

region Xishuangbanna, Yunnan Province, were sampled to determine their mycorrhizal

colonization, spore density, isolation frequency, relative abundance and species

richness of AM fungi. The mycorrhizal colonization rate of host plants were measured

under a BX50 Olympus Microscope with Automatic Photo Micrographic System (320-640

×) after staining with 0.5% acid fuchsin. Spores of AM fungi in aliquots (20 ml)

of each soil were isolated by wet-sieving decanting and cane sugar centrifugal method,

hich were used to identify according to the newest taxonomic system described by

Morton and Redecker (2001). Species richness was measured as the number of species

compared with the number of individuals in the community. Results showed that most

roots collected were colonized by AM fungi, typical arbuscules and vesicles were

formed with various colonization rates (up to 40%, grade VIII), and 0-1.86 vesicles

per mm root length. Species richness on Parashorea chinensis was the highest

(4.31),while Shorea assamica showed the lowest (1.63). Hopea mollissima gave

the maximum spore density (7.76), Vatica astrotricha the minimal (3.09).

Thirty_two AM fungal species belonging to the genera Acaulospora, Glomus,

Paraglomus, Achaeospora and Scutellospora were identified. The frequencies

and relative abundances of AM fungi varied. Acaulospora and Glomus were

likely the dominant proportion in the rhizospheric soil of dipterocarpus plants in

the tropical region. It was suggested that most dipterocarpus plants can form typical

AM and there was high species diversity of AM fungi in tropical dipterocarpaceae

forest. The functional role of these AM fungi in the physiology of dipterocarpus

plants needs further research.