Endophytic fungi in natural and man­made plant communities  Kari Saikkonen, University of Turku  Endophytic fungi are one of the largely untapped resources that likely have several, economically important applications in the future. Both pharmaceutical industry and plant­breeders are interested in endophytes for production of enzymes, medicines and biological control agents. Endophytic fungi live asymptomatically and intercellularly within plant tissues. They have been found in all plant species studied, and they are belived to be as common as root inhabiting mycorrhical fungi. If we assume that there are 400 000 species of vascular plants and each of them has three to six host specific endophytes, the total number of endophyte species in the world would be approximately two million.  Endophytes were recognized for the first time in New Zealand and USA in the end of 1940's when livestock grazing on some pastures suffered from serious, unexplained symptoms. Thereafter, toxic compounds produced by endophytes were found from the grasses on these pastures. Recently number of studies have reported that, in addition to increasing plant resistance to herbivores, endophytes may also enhance plant competitive abilities, germination success, resistance to drought and water stress.  Thus, endophytic fungi and their hosts appear to be quintessential mutualists although the endophyte-plant studies have mainly focused on few cultivars of economically important pasture and turf grasses. Thus, there is an urgent need to examine the interaction of endophytes and their host plants in natural settings with native grass- and tree species.  In this study we will examine fungi in birch trees and several grass species in Finnish nature. We will study how natural or man­made habitat fragmentation affects (1) species distribution and diversity of endophytic fungi, (2) interactions between plants and their endophytes, (3) and thereby competition success, stress tolerance and herbivory resistance of the host plants, and finally (4) the development of plant communities. To answer these questions we will perform a series of field and greenhouse experiments, and compare diversity of endophytes in natural and man­made habitats.  Project title:  Diversity of endophytic fungi in natural and man­made  habitats  Project leader:  Kari Saikkonen  Department of Biology  FIN-20014 University of Turku  tel: +358-2­333 5760 e-mail: karisaik(at) utu.fi