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