The genetic diversity of 85 isolates of Phytophthora infestans collected in 2007 from Gansu province in China was determined and compared with 21 isolates collected before 2004. Among them, 70 belonged to the A1 mating type and 15 were self-fertile (SF). The mitochondrial DNA haplotypes revealed both Ia (25%) and IIa (75%) haplotypes. Metalaxyl resistance occurred with high frequency (54%) in Gansu. Simple sequence repeat (SSR) genotyping revealed 26 genotypes (13 from the Tianshui region) among the 85 isolates, and 18 genotypes among the 21 isolates collected before 2004, without overlap in genotypes detected in the two groups. Cluster analysis showed clear subdivisions within the different mating type isolates. Among Gansu's isolates, Nei's and Shannon's diversity indices were highest in isolates collected in Tianshui where both A1 and SF isolates were found. Analysis of molecular variance of isolates from Gansu indicated that 51% and 49% of the variance was explained by within-area and among-area variance, respectively. The results suggest that the occurrence of SF isolates increases the risk of sexual reproduction, the formation of oospore as initial inocula in the field, and affects the genotypic diversity in the population.

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Olpitrichum tenellum was shown to be a biotrophic mycoparasite, contacting but not penetrating its host hyphae by means of hook-shaped contact cells, which apparently absorb nutrients and growth factors from living host cells. The known hosts are Fusarium moniliforme, Alternaria alternata, and Cladosporium sp. The hyperparasite failed to grow in the absence of the host on glucose – yeast extract medium unless a water extract of the host was added. Keywords: Olpitrichum tenellum, mycoparasite, axenic culture, hyperparasite.

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Paecilomyces hepiali is a species of fungus isolated from a field collection of natural Cordyceps sinensis insect-fungi complex from the Baima Snow Mountains, Diqing Tibetan Autonomous Prefecture, Yunnan Province. A dried culture of living strain 82-2 was designated as the holotype and deposited in the Herbarium of the Institute of Chinese Materia Medica (HICMM), China Academy of Chinese Medical Sciences, Beijing. In 2015 a neotype was designated for P. hepiali based on the presumption that the holotype was unavailable for study. We show that the holotype is extant and available, and thus the neotypification is overturned.