Sexuality and Somatic Incompatibility in Phellinus gilvus

Distinguishing homokaryons and heterokaryons in Phellinus sulphurascens using pairing tests and ITS polymorphisms

“…Therefore, the secondary lines we observed when unrelated homokaryons and heterokaryons were paired represented somatic incompatibility reactions between the newly established heterokaryons. Similar nuclear migration patterns have been described for many other basidiomycetes, e.g., Phellinus gilvus, Schizophyllum commune, Trametes versicolor, and Stereum gausapatum (Ellingboe and Raper 1962;Todd and Rayner 1978;Boddy and Rayner 1982;Rizzo et al 1995). Interestingly, we did not always observe secondary lines being formed in ho-he pairings shown to have resulted in the formation of a new heterokaryon by ITS analysis-in some cases only morphologically different fungal mats were formed.…”

“…Like other members of the Hymenochaetales, heterokaryotic P. sulphurascens does not form clamp connections. As well, in this species both homokaryons and heterokaryons have multinucleate cells (Hansen 1979b;Rizzo et al 1995;Kauserud and Schumacher 2001). Distinguishing heterokaryons (he) from homokaryons (ho) for population and other genetic studies of P. sulphurascens is thus a challenge.…”

Nuclear reassortment between vegetative mycelia in natural populations of the basidiomycete Heterobasidion annosum

“…The single-conidial heterokaryons composed of two nuclei in different combinations were all somatically compatible or weakly incompatible, indicating that a natural chimera had been formed between genetically different mycelia that share alleles at the vegetative incompatibility loci (Buss, 1982). The formation of genetic chimeras from the fusion of two or more genets has previously been reported from the basidiomycete Phellinus gilvus (Rizzo et al, 1995) and is known from several other systems such as Cnidarians and Chordates (e.g., Rinkevich, 1996) and amoebae (Dao et al, 2000). However, to our knowledge it has not previously been reported from natural populations of higher fungi.…”

Genetics and QTL mapping of somatic incompatibility and intraspecific interactions in the basidiomycete Heterobasidion annosum s.l.

“…The morphology of mycelial interactions usually varies among pairings indicating differences in incompatibility. The differences observed in for instance Phellinus gilvus are, complete intermingle of hyphae, a slight sparse zone between paired mycelia with no or little pigmentation, pigmented interaction zone, and distinct pigmentation within the interaction zone (Rizzo et al, 1995). While in Heterobasidion annosum the width of the gap between the interacting mycelia varies and the relative sparseness of aerial mycelia in the interaction zone (Hansen et al, 1993a).…”