Plant Mycorrhiza under Extreme Conditions of Snow Beds Alpine Communities in Armenia

Resumo

Snow-bed alpine communities of the Lesser Caucasus occupy significant areas and form under specific environmental conditions: long-term snow cover and a short growing period (about 2 months). We have assumed that the main components of floristically poor plant communities under these conditions are characterized by a well-developed mycorrhiza. The intensity of mycorrhizal infection was studied on the Aragats Massif (3300 m) according to the approach by I.A. Selivanov, and the percentage of root length colonization was calculated for ten plant species. Well-developed arbuscular mycorrhizas were revealed in all cases, even for representatives of families that usually do not form mycorrhiza (Carex oreophilla (Cyperaceae) and Minuartia aizoides (Caryophyllaceae). The intensity of mycorrhizal infection of Gagea pusilla (58 ± 6%) and Ranunculus dissectus (44 ± 4%) was determined for the first time. Thus, snow bed alpine communitiesare characterized by well-developed arbuscular mycorrhiza of plants, despite pronounced ruderal features.