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During a survey of endophytic fungi from cucurbit plants in China, 21 Talaromyces strains were isolated from ten symptomless plants. Phylogenetic analysis of the partial RNA polymerase II largest subunit gene (RPB2) showed that the strains belong to Talaromyces sections Talaromyces and Islandici. Based on morphological characters and multilocus phylogenetic analysis of the nuc rDNA internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), calmodulin (CaM), and β-tubulin (TUB) genes, the strains were identified as four known species, T. cnidii, T. pinophilus, T. radicus, and T. wortmannii, and two new species. Two new species, T. cucurbitiradicus from pumpkin roots and T. endophyticus from cucumber stems, are described in this study. Talaromyces cucurbitiradicus is morphologically similar to T. funiculosus but differs in the number of phialides per metula and by the production of chlamydospores. Talaromyces endophyticus is morphologically similar to T. cerinus and T. chlamydosporus but differs by producing yellowish colonies and by lacking chlamydospores. Further analyses of polymorphisms in ITS and TUB sequences supported the distinctions among T. cucurbitiradicus, T. endophyticus, and similar species. [ABSTRACT FROM AUTHOR]

Epichloë typhina, a fungal endophyte of cool season grasses, is heterothallic and an obligate out-crosser. In areas of endemism, its spermatia are moved between stromata of the two opposite mating types through egg-laying activities of Botanophila flies. In western Oregon, where the fungus was inadvertently introduced into seed-production fields of Dactylis glomerata (= orchardgrass, cocksfoot), flies do not appear to be the sole vectors for E. typhina fertilization. Here we examined the role of the common agricultural slug pest Deroceras reticulatum and mycophagous slug species Prophysaon andersoni and Arion subfuscus in E. typhina spermatia transfer. Frass from P. andersoni, A. subfuscus and D. reticulatum fed stromata of one mating type was transferred to stromata of the opposite mating type, resulting in 100%, 93% and 25% stromata fertilization respectively. An experiment designed to mimic field conditions examined stromata fertilization on E. typhina-infected plants of opposite mating type in the presence of slugs. Treatments with P. andersoni and D. reticulatum had greater stromata fertilization compared to the no-slug control, but the slug treatments were not different. This appears to be the first report of mollusks vectoring viable spermatia leading to the cross fertilization of stromata of different mating types. [ABSTRACT FROM AUTHOR]