تنوع زيستي ميكوفلور مخمري اكوسيستم جنگلي ارسباران، استان آذربايجان شرقي

Biodiversity of Yeast Mycoflora in Arasbaran Forest Ecosystem, East-Azerbaijan Province - Iran

The yeasts are found in natural habitat in different substrates. Research results indicate that, in different habitats of similar geographic region the substrates for yeasts, as far as number and type are concerned, are very common. Thus, there are difference aspects that were recognized by ecologic conditions and habitat characters. The sampling sites at two areas of Arasbaran Forest Research Station were chosen from different altitudes. In this study two sites were considered, site I was over 1500m and site II was below 1000m. Sixty samples were collected from different parts of plants as substrate for yeasts. The isolated yeasts were identified phenotypically on the basis of macro/micro-morphological and physiological features; like assimilation and fermentation of carbohydrates and nitrogen sources. Identification was made according to the standard taxonomic keys edited by: Barnett J.A., Payne R.W., Yarrow D., 1990 and Kurthzman C.P., Fell J.W.,1998. Species richness was calculated as number of different species per sampling site. The analysis of yeast biodiversity was done by means of Shannon-Weaver index. Of the 129 isolates obtained, 37 cases (28.68%) had ascomycetic affinity and 92 cases (71.32%) were basidiomycetic. Important species that identified were Rhodotorula spp. with red colony (n=17), Sporobolomyces spp.(n=12), Aureobasidium pullulans with gray to black colony (n=6), Cryptococcus spp. (n=13), particularly Cryptococcus podzolicus (n=8), and Debaryomyces spp. (n=6). Shannon-Weaver biodiversity index (Hʹ or C ) (Natural logarithm e=2.718) value in Arasbaran forest research site during sampling time with yeasts richness (S=129) was (HL3.036 and =20.83). Yeast diversity and richness were higher at first sampling site (S=88), (HL3.008 and eHʹ J20.25) than the second sampling site (S=41), (Hʹ=2.722 and eHʹ=15.22).