Identification of seedling and slow stripe rust resistance genes is important for gene pyramiding, gene deployment, and developing slow-rusting wheat cultivars to control the disease. A total of 98 Chinese lines were inoculated with 26 pathotypes of Puccinia striiformis f. sp. tritici for postulation of stripe rust resistance genes effective at the seedling stage. A total of 135 wheat lines were planted at two locations to characterize their slow rusting responses to stripe rust in the 2003-2004 and 2004-2005 cropping seasons. Genes Yr2, Yr3a, Yr4a, Yr6, Yr7, Yr9, Yr26, Yr27, and YrSD, either singly or in combinations, were postulated in 72 lines, whereas known resistance genes were not identified in the other 26 accessions. The resistance genes Yr9 and Yr26 were found in 42 and 19 accessions, respectively. Yr3a and Yr4a were detected in two lines, and four lines may contain Yr6. Three lines were postulated to possess YrSD, one carried Yr27, and one may possess Yr7. Thirty-three lines showed slow stripe rusting resistance at two locations in both seasons.

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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.