Ecological Distribution Of Arbuscular Mycorrhizal Fungi And Glomalin In The Rhizosphere Of Scutellaria Baicalensis

Scutellaria baicalensis, labiatae, is the anthentic Chinese herbal medicine in Hebeiprovince and its roots are used as medicines. Anguo, located in the southern parts of Hebeiprovince, is well known at home and abroad as its excellent Chinese herbal medicine.Chengde, located in the northeast parts of Hebei province, has enjoyed a good reputation forthe quality of Scutellaria baicalensis. AM fungi, widely exist in various ecological systemand form mutualistic symbiois with90%vascular plant. AM fungi have many beneficialeffects on plant and are knowed as “bio-fertilizer”. Glomalin, produced by arbuscularmycorrhiza fungi (AMF), is a glycoprotein containing metal elements, and it has importantfunctions for both AMF and the terrestrial ecological system.In this research, the symbiois relationship between Scutellaria baicalensis and AM fungiwas taken the entry point. The community composition, species diversity, ecologicaldistribution and their relations with soil C and N in the rhizosphere of Scutellaria baicalensisin Anguo and Chengde were investigated and analyzed in2010and2011.Results were showed as follows:1An abundant diversity of AM fungi was found in the rhizosphere of Scutellariabaicalensis in Hebei province.32AM fungal species belonging to4genera were isolantedfrom soil samples in6different sites. Of Anguo and Chengde, there were8to Acaulospora,accounted for25%;1to Entrophospora, accounted for3.1%;19to Glomus, accounted for59.4%;4to Scutellospora, accounted for12.5%. Glomus and Acaulospora were the dominantgenera in Anguo and Chengde, Entrophospora occurred only in Anguo.2The AM fungal community composition in the rhizosphere of Scutellaria baicalensisin6different sites in Hebei province was different.24AM fungal species belonging to4genera were isolanted from soil samples in3different sites in Anguo and there were6AMfungi species only found in Anguo.26AM fungal species belonging to3genera wereisolanted from soil samples in3different sites in Chengde and there were8AM fungi speciesonly found in Chengde. A. bireticulata, existed most widely, was the common dominant specie in Anguo and Chengde and G. reticulatum was another common dominant species inAnguo, while there was a great deal of difference about the dominant species in Chengde,mostly belonging to Acaulospora.3The well symbiois relationship (the intermediate type mycorrhizas) can be formedbetween Scutellaria baicalensis and AM fungi in Hebei province, the average spore densitywas up to3596/100g soil, and the average total colonization reached81.7%.4There were certain regularity of species richness, Shannon-Wiener index and evennesson the temporal distribution in the rhizosphere of Scutellaria baicalensis in Anguo. Speciesrichness and Shannon-Wiener index of AM fungi increased initially and later decreased fromJune and October, decreased in the following order: August＞September＞October＞July＞June; the minimum value of evenness occurred in June, while the maximum value ofevenness occurred in August and September. From the spatial perspective, in July, speciesrichness, Shannon-Wiener index and evenness in the rhizosphere of Scutellaria baicalensis inAnguo were below Chengde.5The colonization and spore density of AM fungi in the rhizosphere of Scutellariabaicalensis closely related with the sampling time and sites. Spore density of AM fungi in therhizosphere of Scutellaria baicalensis in Anguo decreased initially and later increased; hyphal,vesicular and total colonization of AM fungal gradually increased from June to October, thehighest colonization and the maximun spore density existed in October. The average sporedensity and all average colonization (hyphal, vesicule, arbuscule and total colonization) in2011exceeded2010in Jidi. From the spatial perspective, in July, the average spore density,hyphal, vesicule and total colonization in Chengde were above Anguo.6The ecology distributon of AM fungi and glomalin in the rhizosphere of Scutellariabaicalensis closely related with the dynamic change of content of soil C and N. Soil organic Cand total N had significantly positive correlation with spore density, hyphal, vesiculecolonization, total glomalin and easily extractable glomalin; species richness andShannon-Wiener index had a positive correlation with soil C and total N, soil pH had anegative correlation with hyphal colonization; soil available P showed a negatively correlated with spore density.7The results of linear regression equation showed that soil organic C and total N had asignificantly linear relationship with total glomalin and easily extractable glomalin. The Ccontent of total glomalin accounted for averagely4.5%of content of soil organic C and the Ncontent of total glomalin accounted for averagely14.6%of content of soil total N, which canshow that glomalin was an important resource of the soil C and N. The content of totalglomalin can be used as an effective evaluations for the soil organic C and total N dynamiccycle in the rhizosphere of Scutellaria baicalensis.