Fungi in Antarctica

摘要

Fungi are generally easily dispersed and are able to colonize a very wide variety of different substrata and to withstand many different environmental conditions. Because of these characteristics they spread all over the world. The Antarctic mycoflora is quite diversified within the different climatic regions of the continent. Most Antarctic microfungi are cosmopolitan; some of them are propagules transported to Antarctica but unable to grow under the Antarctic conditions,while others,termed indigenous,are well adapted and able to grow and reproduce even at low temperatures,mostly as psychrotolerant,or fast sporulating forms,able to conclude their life-cycles in very short time. In the most extreme and isolated areas of the continent,such as the Antarctic Dry Valleys,endemic species showing physiological and morphological adaptations have locally evolved. Most Antarctic fungi,as well as fungi from other dry and cold habitats,are adapted to low temperatures,repeated freeze and thawing cycles,low water availability,osmotic stress,desiccation,low nutrients availability and high UV radiation. Sometimes single strategies are not specific for single stress factors and allow these microorganisms to cope with more than one unfavourable condition.