• Korean journal of applied entomology
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• v.49 no.1
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• pp.17-22
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• 2010

Pachynematus itoi Okutani emerges three times a year, and overwinters as a pre-pupa in cocoon. First emergence of P. itoi was from 7th May to third June. Second and third emergence was from 20th June to 13th July and fourth to 25th August, respectively. Mean oviposited egg number was 59, and egg period was about 9 days. Hatching rate was >90%. Oviposited egg number was the highest in the first needle cluster of short shoot followed by second and third. P. itoi did not oviposit on single needle (long shoot) of Larix leptolepis (Sieb. et Zucc.). Larva had five instars, and larval period was about 20 days. Larva prefer needle cluster of short shoot to single needle of long shoot. Mature larva descended from host tree and pre-pupa in cocoon overwinter at topsoil.

• Research in Plant Disease
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• v.17 no.3
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• pp.386-390
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• 2011

In June 2011, walnuts (Juglans regia) from orchards in Kimcheon and Muan, in southern Korea, were found to exhibit downy mildew-like symptoms of a foliar disease. Whitish polygonal efflorescence was produced on the abaxial surface of affected leaves and discolored light green blotches on the corresponding adaxial surfaces. In the later stage of disease development, diseased tissues collapsed and became necrotic. Based on morphological and cultural characteristics, the causal fungus was identified as Microstroma juglandis. The sequence of ITS rDNA of the present isolate showed 100% similarity with those of M. juglandis obtained from GenBank databases, thus confirming its identity. Pathogenicity tests were conducted on leaves of walnut seedlings, fulfilling Koch's postulates. The disease has been previously reported in North America, Europe, Oceania and some western Asia. This is the first report of downy leaf spot on walnuts in East Asia.

• Research in Plant Disease
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• v.17 no.2
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• pp.228-231
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• 2011

Since 2008, a new leaf spot disease has been found in loquat tree (Eriobotrya japonica) at a nursery station in Goheung, Korea. Above 50% of the seedlings developed the spot symptoms on the leaves. The infected plants were generally reduced in the seedling vigour and early defoliation was occurred. The infected leaves developed grayish lesion with dark reddish brown margin. The pathogen developed round to ellipsoidal acervuli on the lesion. Based on morphological characteristics of the pathogen, the fungus was identified as Entomosporium mespili. The cultured pathogen successfully reproduced the same disease symptom on the leaves of loquat tree and found to be E. mespili. A monoconidial culture was deposited in Korean Agricultural Culture Collection (KACC 44727). This is the first report of E. mespili causing leaf spot of loquat tree in Korea.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1568-1572
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• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• The Plant Pathology Journal
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• v.28 no.4
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• pp.409-417
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• 2012

We identified two novel expansin (EXP) genes in the expressed sequence tag database of Bursaphelenchus xylophilus, designated as Bx-EXPB2 and -EXPB3. Novel Bx-EXPBs encoded 150 amino acids and their similarities in coding sequence were 70.7-84.0% to the previously reported EXPB1 of B. xylophilus. Bx-EXPB2 and Bx-EXPB3 were clustered with Bx-EXPB1 and Bm-EXPB1, respectively, forming the independent phylogeny with other nematode EXPs. All identified Bx-EXPBs contained the signal peptide and were only expressed during the propagative stage, suggesting that they are secreted to facilitate nematode migration through hosts by loosening cell walls during infection. Quantitative real-time PCR analysis showed that the relative accumulation of Bx-EXPB3 mRNAs was the highest among the three Bx-EXPs examined and the order of mRNA accumulation was as follows: Bx-EXPB3 > Bx-EXPB2 >> Bx-EXPB1. Homology modeling of Bx-EXPBs showed that the structurally optimum template was EXLX1 protein of Bacillus subtilis, whichshared residues essential for catalytic activity with Bx-EXPB1 and Bx-EXPB2 except for Bx-EXPB3. Taken together, Bx-EXPB1 and Bx-EXPB2 may be involved migration through plant tissues and play a role in pathogenesis.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.30-34
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• 2008

This study was conducted to develop environmental techniques to reduce chestnut insect pests. The study sites were selected in intensive chestnut orchards of Jinju city, Gyeongnam province. In early and middleripening cultivars of chestnut tree, the damage of chestnut fruits by Dichocrocis punctiferalis was significantly lower in wromstop than other treatment such as Capture-machine, Nemacatch and Naphthalene (p<0.05), while there was no significant difference among treatments in late-ripening cultivars. The control effect of D. punctiferalis showed the highest in wormstop treanment with 90.68% and 80.58% in early and middle-ripening cultivars. The control effects for Curculio sikkimensis in late-ripening cultivars of chestnut tree was 80.58% in Nemacatch and 77.90% in Wormstop treatment.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.113-116
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• 2010

The Acacia seyal Del. var. seyal belongs to family Mimosaceae is known locally as gum Talha tree. It is a multipurpose tree species occurs throughout the African gum belt in Savannah mostly in pure forest. In Sudan it thrives on heavy clay soils that receive an annual rainfall between 400-800 mm. It is an important source of rural energy (fuelwood and charcoal) and forage. As mentioned by Nair (2007) the economic damage causes by insect in natural forest often difficult to judge due to no enough research attention The tree is frequently affected by biotic factors among them the insect pests. During a survey in the 1980's the tree was severely infested by the longhorned beetles (Cerambycidae) severely infesting other Acacia species, but the ecological data are overlooked. Therefore, the objective of the study was to assess infestation characteristics and to determine environmental factors triggering the attack of longhorned beetles. A temporary random sampling technique was applied to observe the damage characteristics of the longhorned beetles on tree species during May-July 2007. Five sample plots occupies by A. seyal were taken in Kordofan region directly observed for the presence of hole of emergence of the longhorned beetles, presence of dusts, presence of insect stages, girdling as well as other characteristics of damage. The study results indicate that the infestation rate of trees in the sampled sites ranged between zero and 23.08%. Further ecological researches are recommended.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.190.4-191
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• 2003

This study was carried out to examine the constituents of Amorpha fruticosa (Leguminosae), a shrub originated from North Africa. Dried and ground fruit of A. fruticosa were extracted with methanol and then concentrated to give the crude extracts. The crude extracts was successively fractioned with organic sovents, such as n-hexane, CH$_2$Cl$_2$ and EtOAc. Seven compounds were isolated from the fruits of A. fruticosa. On the basis of spectrosopic data, the structures of these compounds were determined as: kaempferol 7-O-${\alpha}$-L-rhamnopyranoside (I), methyl 3,4,5- trihydroxybenzoate (methyl gallate, II), tephrosin (III), dalbinol (IV), gallic acid (V), 2",4",5",7-tetramethoxyisofavone (Ⅵ) and Dalbinol 2"-O-${\beta}$-D-Glucopyranoside (Ⅶ) respectively. (omitted)

• Korean journal of applied entomology
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• v.59 no.2
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• pp.117-127
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• 2020

We monitored on the hitchhiker insect pests from a total of 112 foreign vessels entering into Korea during 109 days from 1. Jun. to 17. Sep. in 2018. As the results, a total of 336 samples of the hitchhiker insects were collected using simply collecting method by hands, one of interception method and identified as 159 species of 47 families under nine orders on the basis of integrative species identification. Among them, 14 species of nine families under three orders were detected as undistributed species in South Korea. We reported on the 14 undistributed species in South Korea with the data sheets for the risk assessments on invasive or invasive likelihood species. Also, we suggested and used the term 'not-distributed species' for avoiding confusion with 'unrecorded species', 'unreported species', or 'new reported species'.

• The Korean Journal of Mycology
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• v.49 no.1
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• pp.21-31
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• 2021

Auricularia (Auriculariaceae, Basidiomycota) is well-known jelly fungi, and most species are cultivated or utilized medicinally around the world. A total of 127 Auricularia specimens were collected during Korean mushroom forays by the Korea National Arboretum from 2008 to 2020. In this investigation, fungal barcode analysis and morphological examinations of 33 specimens were conducted and five Korean Auricularia species were identified. Of the species identified, A. americana, A. heimuer, and A. villosula were new to Korea, while A. auricula-judae which was previously identified in Korea, was not found. Herein, we discuss the Korean Auricularia species and provide a taxonomic key for their morphological identification.