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Yang C.Y.,South Korean National Institute of Animal Science | Lee H.S.,Gyeongsangnam do Agricultural Research and Extension Services | Park C.G.,Gyeongsang National University
Journal of Chemical Ecology

The smaller clearwing moth, Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae), is a major pest of persimmon in northeast Asia. A previous study reported attraction of S. tenuis males to Z3,Z13-18:OAc, but this compound had no effect on male catch in the persimmon orchards in Korea. In this study, we analyzed pheromone gland extracts of S. tenuis females and identified Z3,Z13-18:OH as the main component. In field trapping trial, Z3,Z13-18:OH alone was attractive to S. tenuis males and competitive with live virgin females. These results indicate that the pheromone of this species consists of a single component, Z3,Z13-18:OH. However, Z3,Z13-18:OAc, a previously reported attractant, was not detected in the gland extracts of females. Furthermore, the addition of Z3,Z13-18:OAc to the main pheromone component strongly inhibited attraction for males, suggesting that the diene acetate is not a pheromone component. This is the first report of an octadecadienol as female-produced sex pheromone from the genus Synanthedon. © 2012 Springer Science+Business Media, LLC. Source

Kwon J.-H.,Gyeongsangnam do Agricultural Research and Extension Services | Kim J.,Gyeongsang National University | Kim W.-I.,South Korean National Institute of Animal Science

Soft rot in apple caused by Rhizopus oryzae was found for the first time in Korea. A detailed description of the specimen is given along with its internal transcribed spacer rDNA sequence. The fungus was identified as Rhizopus oryzae based on the mycological characteristics, molecular data, and pathogenicity testing. © The Korean Society of Mycology. Source

Kwon J.-H.,Gyeongsangnam do Agricultural Research and Extension Services | Kang D.-W.,Gyeongsangnam do Agricultural Research and Extension Services | Kim S.-R.,Gyeongsangnam do Agricultural Research and Extension Services | Kim J.,Gyeongsang National University
Plant Disease

Passion fruit (Passiflora edulis) is a vine species of passion flower that is native to Brazil, Paraguay, and northern Argentina. In South Korea, it is widely grown for its sweet and seedy fruit. In March 2014, passion fruit flowers with gray mold (approximately 50% incidence) were sampled from the exhibition field of the Agricultural Technology Service Center in Jinju, South Korea. Symptoms first appeared on flowers, which turned brown and then died, with masses of gray or brownish spores produced on infected tissues. No gray mold symptoms were observed on leaves, stems, or fruit. To isolate fungal pathogens, diseased flower tissues excised from the margins of lesions were surface-disinfested in 1% NaOCl for 10 s, rinsed three times with sterile distilled water, and placed on water agar and cultured at 25°C for 2 days. Mycelial tips of developing fungal cultures were transferred to potato dextrose agar (PDA) for identification. Five Botrytis isolates were recovered from the infected plant samples. All fungal colonies were gray brown and produced sclerotia on PDA. The conidia were one-celled, mostly ellipsoid or ovoid, and colorless or pale brown. The conidia were 6 to 19 × 4 to 12 μm (n = 50) and conidiophores were 15 to 33 μm long. Based on the morphological characteristics, the fungi were placed in the Botrytis cinerea group (Ellis and Waller 1974). To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA region of a representative isolate MHGNU F114 was amplified using ITS1/ITS4 primers (White et al. 1990). The DNA products were cloned into the pGEM-T Easy vector (Promega, Madison, WI) and the resulting plasmid (pOR187) was sequenced using universal primers at Macrogen Services (Daejeon, South Korea). A BLASTn search of the ITS rDNA sequence of the isolate MHGNU F114 (GenBank Accession No. KU234690) confirmed the identity of the fungus; the sequence obtained was homologous and shared 99% identity with the B. cinerea isolate LGM002 from Brazil and clone GTB from Florida, causing gray mold on pea (KC683713) and German thyme (KT737373), respectively (Dallagnol et al. 2014). For further confirmation, two nuclear protein-coding genes were sequenced: heat-shock protein 60 (HSP60) and DNA-dependent RNA polymerase subunit II (RPB2) (Staats et al. 2005). The HSP60 and RPB2 sequences (KU760985 and KU760986) of the isolate were 99 to 100% identical to those of B. cinerea strains B05.10 and T4, respectively. Isolate MHGNU F114 was used to conduct pathogenicity tests on the flowers of two 1-year-old passion fruit plants grown in pots. Five flowers from one passion fruit plant were inoculated by spraying a conidial suspension of 3 × 105 conidia/ml until run-off. Five negative control flowers of another passion fruit plant were treated with sterilized distilled water. The two plants were stored in a moist chamber with >90% relative humidity at 25°C, and after 2 days the plants were placed in a greenhouse. Seven days after inoculation, gray mold symptoms similar to those observed in the field developed on the inoculated flowers, whereas the control flowers remained asymptomatic. B. cinerea was reisolated from the lesions of the inoculated flowers to fulfill Koch’s postulates. The morphological features of fungi reisolated from inoculated flowers were the same as those of the original isolates. To our knowledge, this is the first report of gray mold caused by B. cinerea on P. edulis in Korea. © 2016 The American Phytopathological Society. Source

Kwon J.-H.,Gyeongsangnam do Agricultural Research and Extension Services | Choi O.,Gyeongsang National University | Kim J.,Gyeongsang National University | Kwak Y.-S.,Gyeongsang National University
Journal of Phytopathology

In the summers of 2010 and 2011, an anthracnose disease was observed on the Jatropha curcas L. grown at the research field of Gyeongsangnam-do Agricultural Research and Extension Services, South Korea. The symptoms included the appearance of dark brown spots on the leaf and fruit and the mummification of the fruit. The causal fungus formed grey to dark grey colony on potato dextrose agar. Conidia were single celled, ovoid or oblong, and 8-15×3-5μm in size while seta was dark brown, cone-shaped and 25-46×2-6μm in size. The optimum temperature for growth was approximately 30°C. On the basis of mycological characteristics, pathogenicity test and molecular identification using internal transcribed spacer rDNA sequence, the fungus was identified as Colletotrichum gloeosporioides. To our knowledge, this is the first report of an anthracnose caused by C. gloeosporioides on J. curcas plant in Korea. © 2012 Blackwell Verlag GmbH. Source

Hong M.J.,Dong - A University | Lee Y.M.,Dong - A University | Son Y.S.,Gyeongsang National University | Im C.H.,Gyeongsangnam do Agricultural Research and Extension Services | And 4 more authors.
Biochemical and Biophysical Research Communications

Rab proteins play an essential role in regulating vesicular transport in eukaryotic cells. Previously, we characterized OsRab11, which in concert with OsGAP1 and OsGDI3 regulates vesicular trafficking from the trans-Golgi network (TGN) to the plasma membrane or vacuole. To further elucidate the physiological function of OsRab11 in plants, we performed yeast two-hybrid screens using OsRab11 as bait. OsOPR8 was isolated and shown to interact with OsRab11. A co-immunoprecipitation assay confirmed this interaction. The green fluorescent protein-OsOPR8 fusion product was targeted to the cytoplasm and peroxisomes of protoplasts from Arabidopsis thaliana. OsOPR8 exhibited NADPH-dependent reduction activity when 2-cyclohexen-1-one (CyHE) and 12-oxo-phytodienoic acid (OPDA) were supplied as possible substrates. Interestingly, NADPH oxidation by OsOPR8 was increased when wild-type OsRab11 or the constitutively active form of OsRab11 (Q78L) were included in the reaction mix, but not when the dominant negative form of OsRab11 (S28N) was included. OsRab11 was expressed broadly in plants and both OsRab11 and OsOPR8 were induced by jasmonic acid (JA) and elicitor treatments. Overexpressed OsRab11 transgenic plants showed resistance to pathogens through induced expression of JA-responsive genes. In conclusion, OsRab11 may be required for JA-mediated defense signaling by activating the reducing activity of OsOPR8. © 2013 Elsevier Inc. Source

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