Yeasts of the Georgian honeysuckle <i>(Lonicera iberica)</i> and grapes <i>(Vitis vinifera)</i> in Dagestan

Abstract

Ecological and taxonomic study of mycobiota of cultivated plants and native flora, including endemic ones, from phylogenetic systematics’ perspective, remains one of the interesting topics of microbial ecology. The structure of yeast communities of endemic to the Caucasus Georgian honeysuckle in comparison with grapes, a traditional agricultural crop of the republic, has been studied in the territory of Dagestan. The yeast complex of grapes was studied in ampelocoenoses located on the plain and in the foothills, and in shrubs of Georgian honeysuckle also on the plain and in the mountains. The number of yeasts (per unit of weight) on the plants is higher than in soils, with the highest number of yeasts found on leaves. Grape and honeysuckle berries’ surfaces contain more yeasts than leaves. The influence of grape cultivars on the species diversity and abundance of yeasts was observed, as well as a tendency for their abundance to decrease with increasing altitude. On the contrary, Georgian honeysuckle growing in the mountains and the soil under it was colonized by yeasts more than on the plain. Its species structure included five species, two of which — Aureobasidium pullulans and Metschnikowia pulcherrima — are also typical for ampelocoenosis. Yeast population of plant endemic on the plain was notable for specificity, one of two isolated species was found and identified for the first time as a new species of the genus Zygotorulaspora — Z. dagestanica, associated with leaves and soil, where they dominate being 79.2% of the total yeast number. Despite the close climatic conditions of sites with wild plants and grapes in the plain, their taxonomic composition differed significantly and included two and nine species, respectively. The results obtained show the perspective of studying yeast communities of endemic plants.