Genetic and biological characteristics ofTyphula ishikariensis isolates from Norway

Abstract

Isolates of Typhula ishikariensis, a snow mold fungus, were collected from five localities in Norway. They were divided into three groups according to genetics, cultural morphology, etc. Group I grew normally at 10 ~ Its mating patterns with Japanese taxa were variable: compatible with both biotypes A and B; compatible with biotype A but incompatible with biotype B; and incompatible with both biotypes. Group I was prevalent in southern inland districts such as Buskerud, Oppland, and Hedmark. Group II had smaller sclerotia as compared to other groups, and its sclerotia were often covered with white mycelium in nature and in culture. Group II was compatible with biotype B only. Group III was characterized by irregular growth at 10 o C and genetic incompatibility with biotypes A and B. Cultural morphology of group III resembled that of group I at 0 o C. Rind cell patterns of sclerotia did not separate these two groups or biotypes. Isolates of groups II and III were often obtained from coastal regions in Finmark. Mating reactions were variable: monokaryons were compatible with their respective dikaryons, and monokaryons of groups II and III occasionally mated with group I dikaryons. Dikaryons of groups II and III, however did dikaryotize monokaryons of other groups. Norwegian isolates of T. ishikariensis were highly variable, and the orthodox nomenclature system seemed inapplicalbe at the infraspecific level.

Cold adaptation in the phytopathogenic fungi causing snow molds

“…Matsumoto et al (1982Matsumoto et al ( , 1983 found two intersterility groups (biotypes A and B) within Japanese isolates but included them in a single species, T. ishikariensis, because these biotypes could be genetically related through North American taxa. Matsumoto et al ( , 1996 also divided Norwegian isolates into three groups (groups I, II, and III) based on cultural characteristics and mating reactions with Japanese biotypes. Finally, Matsumoto (1997) classifi ed this fungus into two biological species (biological species I and II) based on morphologies and mating reactions.…”

Environments influence the psychrophily of fungi and oomycetes in the cryosphere

“…In Norway, the basidiomycetous snow mould fungus, Typhula ishikariensis was divided into three groups (I, II and III) based on their mating reaction (Matsumoto & Tronsmo 1995, Matsumoto et al 1996. T. ishikariensis group III is prevalent in the northernmost part of Norway (Matsumoto & Tronsmo 1995, Matsumoto et al 1996, Greenland (Hoshino et al 2006), and Svalbard (Hoshino et al 2003).…”

“…T. ishikariensis group III is prevalent in the northernmost part of Norway (Matsumoto & Tronsmo 1995, Matsumoto et al 1996, Greenland (Hoshino et al 2006), and Svalbard (Hoshino et al 2003). The distribution pattern of this fungus indicates that group III is more adapted to low temperatures than groups I and II.…”

“…The distribution pattern of this fungus indicates that group III is more adapted to low temperatures than groups I and II. Isolates of groups I and II grow normally at 10°C on PDA, whereas group III isolates show irregular growth at this temperature (Matsumoto et al 1996, Hoshino et al 1997, and hyphal growth stops at 15°C. However, mycelia of group III isolates showed normal growth at 10°C when PDA cultures were covered with water .…”

Typhulacf.subvariabilis, new snow mould in Antarctica

“…Two psychrophilic snow moulds Spirorbis borealis and Typhula ishikariensis are also widely distributed not only in the cool temperate zone and frigid zone but also in Arctic regions such as Alaska and the Yukon (Lebeau and Longston 1958; McBeath 2002), Greenland (Hoshino et al 2006), Finnmark (northern Norway: Årsvoll 1975; Matsumoto and Tronsmo 1995; Matsumoto et al 1996), Iceland ( S. borealis not found: Kristinsson and Guðleifsson 1976; Hoshino et al 2004), Lapland (northern Finland and Sweden: Jamalainen 1949, 1957; Ekstrand 1955), Svalbard (Hoshino et al 2003), Russian Arctic (Tkachenko 2013). Their distribution pattern suggests that S. borealis and T. ishikariensis are highly adapted to the Arctic environment.…”