Kari Korhonen (biologist)
Kari Korhonen (born July 24, 1943 in Sotkamo) is a Finnish mycologist and forest pathologist, known for his studies of fungi causing root rot. Korhonen graduated as a biologist from the University of Helsinki in 1968. He made his career as a researcher at the Finnish Forest Research Institute in Helsinki, beginning in 1973. From the start his research concentrated on the forest pathogen fungi then known as "Heterobasidion annosum" and "Armillaria mellea". During his career over 40 years he collected more than 4000 isolates of these species in Scandinavia, Germany, Italy, Greece, USA, Canada, Estonia, Belarus , Siberia and China. Initially, following Veikko Hintikka's discovery of a technique to distinguish between "Armillaria" species by growing them together as single spore isolates on petri dishes and observing changes in the morphology of the cultures, Korhonen showed in 1978 that the European "Armillaria mellea" species complex could be separated into five reproductively isolated species. Similarly he studied the sexual incompatibility of bipolar systems also in "Heterobasidion". As result of these studies the genus "Heterobasidion" was divided into three species while "Armillaria" has by now been divided into more than 40 species. Korhonen has published more than 50 scientific  papers in international journals and edited books, almost all dealing with root rot fungi and their antagonists. For his pioneering work, he received an honorary doctorate from the University of Monaco of Bavaria in 1992. Fungal species named in honor of Korhonen include "Entoloma korhonenii" (Noordeloos 2004) and "Hygrophorus korhonenii" (Harmaja 1985).