XVI International Botanical Congess

Though the symbiotic nature of lichens has been introduced more than 100 years ago, little is known about the degree of selectivity of the partaking bionts. Only the selectivity can be investigated, the hypothesis of coevolution has to be derived from these studies. Strategies to screen for photobiont selectivity of the mycobiont can focus on the photobiont inventory of mycobionts in respect to their phylogenetic relationships, the geographical occurrence of a single species, populations of a single species or the photobiont inventory of lichen associations. Ecological preferences of lichen algae have always to be considered as well. Examples for the different approaches will be given and advantages and disadvantages will be discussed.