Publications by authors named "Yunwoo Jang"

Anthropogenic-mediated climate change is expected to negatively affect pest management in agriculture. Hence, we investigated the oviposition, immature mortality, and developmental processes of species ( (Hübner) and (Fabricius)) under different temperatures (20, 25, and 30°C) and relative humidity (RH) (30-35, 50-55, 70-75, and 90-95%) conditions. For fecundity, mouths of each species were released into a rectangular box whose inner walls were covered with a sheet of white paper for each combination of temperature and RH.

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The tobacco cutworm, (Fabricius) (Lepidoptera: Noctuidae), is one of the most serious pests in field crops, vegetables, and ornamentals. Temperatures (15, 20, 25, 27, 30, 35, and 40 °C), host plants (soybean ( (L.)), maize ( L.

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Article Synopsis
  • Perilla (Perilla frutescens L.) is a significant crop in Korea, ranking second in upland crops and third in edible oil production.
  • A disease survey conducted in Busan in September 2021 revealed vein necrosis symptoms in perilla, with approximately 30%-50% incidence in two fields; affected leaves showed water-soaked spots that progressed to black or brown lesions.
  • The isolated bacterium from the diseased tissues was identified as Pseudomonas cichorii through DNA analysis, known for causing damage to various plants globally, confirming its presence in South Korea.
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Soybean ( L.) is one of the most important crops worldwide. In South Korea, three species of have been reported as causal pathogens of Fusarium wilt of soybean (KSPP, 2021).

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Perilla seed bugs (Nysius sp.) are considered to be the emerging pests causing nutritional and yield losses in perilla and cereal crops. A survey of perilla seed bugs on weeds and perilla crops was conducted over the course of 2 yr in Korea to determine the species composition, abundance, and seasonal dynamics of perilla seed bugs.

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Soybean ( L.) is one of the most important crop plants in the Republic of Korea. Here, we conducted a soybean virome study.

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We determined the complete genome sequence of a putative novel ilarvirus, tentatively named "peanut virus C" (PVC), identified in peanut (Arachis hypogaea). The three segmented genomic RNA molecules of PVC were 3474 (RNA1), 2925 (RNA2), and 2160 (RNA3) nucleotides in length, with five predicted open reading frames containing conserved domains and motifs that are typical features of ilarviruses. The three genomic RNAs shared nucleotide sequence similarity (74% identity and 93% query coverage for RNA1, 75% identity and 85% query coverage for RNA2, and 72% identity and 70% query coverage for RNA3) with the most closely related ilarvirus, parietaria mottle virus.

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The root of Hibiscus syriacus (Malvaceae) has been used for treatment of fungal diseases such as tinea pedis (athlete's foot). In this study, we investigated the antifungal constituent of the root of Hibiscus syriacus Ggoma, which was produced by a mutation breeding using gamma ray irradiation, and compared the antifungal activity of H. syriacus Ggoma and its parent type.

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Xylaria, belonging to the Ascomycotina, is known to produce diverse classes of bioactive substances. In an effort to identify the chemical constituents of the fruiting bodies of Xylaria polymorpha, linoleic acid (1), linoleic acid methyl ester (2), ergosterol (3), 4-acetyl-3,4-dihydro-6,8-dihydroxy-3-methoxy-5-methyl-1H-2-benzopyran-1-one (4), and 4-hydroxyscytalone (5) were isolated from its methanolic extract. Their structures were assigned on the basis of various spectroscopic studies.

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Two new polypropionates designated as xylarinic acids A and B were isolated from the fruiting body of Xylaria polymorpha. Their structures were established as 4,6,8-trimethyl-2,4-decadienoic acid and 2,4,6-trimethyl-2-octenoic acid, respectively, on the basis of extensive spectroscopic analysis. Both compounds displayed significant antifungal activity against plant pathogenic fungi Pythium ultinum, Magnaporthe grisea, Aspergillus niger, Alternaria panax, and Fusarium oxysporium, whereas they did not show antibacterial and cytotoxic effect.

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Article Synopsis
  • New triterpene glucosides named oligoporins A, B, and C were found in the methanolic extract of the fungus Oligoporus tephroleucus.
  • The structures of these compounds were determined using spectroscopic techniques.
  • These compounds showed a strong protective effect against DNA damage caused by hydroxyl radicals generated in a chemical reaction involving hydrogen peroxide and ferrous ions.
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