• Mycobiology
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• v.49 no.3
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• pp.223-234
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• 2021

Itajahya rosea was found growing in association with Leucaena leucocephala plants at Savitribai Phule Pune University campus in India. The species identity was confirmed by phylogenetic analysis based on ITS and LSU regions of rDNA, wherein, our fugus was placed along with I. rosea in phylogenetic tree. It represents first record of I. rosea from India. Frequent visitation by Drosophila species on I. rosea fruiting body particularly on gleba was observed. The Drosophila got attracted to the detached gleba under the laboratory conditions and even sometimes, they prefer to sit over the gleba as compare to their food banana. It suggested that I. rosea gleba or pseudostipe produces some compounds for attraction and feeding behavior of Drosophila species. Therefore, we characterized the volatile attractants produced by gleba and pseudostipe of I. rosea by GC-MS analysis. Nineteen compounds were identified from gleba while nine compounds were recovered from the pseudostipe. Out of them, blends of three abundant odor producing volatile compounds were reported namely, Hexadecane, Pentadecane and Nonadecane, which are responsible for attraction of Drosophila toward the gleba. Three fatty acids namely 9,12-octadecadienoic acid (Z,Z), hexadecanoic acid and benzoic acid ethyl ester produced are served as an appetitive signal through olfactory response of Drosophila, so the flies were feed on the gleba. Two pheromones' compounds, heneicosane and (+)-(5S,9S)-5,9-dimethylpentadecane, were also reported in pseudostipe and gleba, respectively, which play a role in Drosophila for breeding. Our study highlights an intriguing chemical ecology of fungus-Drosophila interaction.

• Mycobiology
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• v.46 no.4
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• pp.407-415
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• 2018

Pheromone (PHB)-receptor (RCB) interaction in the mating pheromone response pathway of Lentinula edodes was investigated using synthetic PHBs. Functionality of the C-terminally carboxymethylated synthetic PHBs was demonstrated by concentration-dependent induction of a mating-related gene (znf2) expression and by pseudoclamp formation in a monokaryotic strain S1-11 of L. edodes. Treatment with synthetic PHBs activated the expression of homeodomain genes (HDs) residing in the A mating type locus, and of A-regulated genes, including znf2, clp1, and priA, as well as genes in the B mating type locus, including pheromone (phb) and receptor (rcb) genes. The synthetic PHBs failed to discriminate self from non-self RCBs. PHBs of the B4 mating type (B4 PHBs) were able to activate the mating pheromone response pathway in both monokaryotic S1-11 and S1-13 strains, whose B mating types were B4 (self) and B12 (non-self), respectively. The same was true for B12 PHBs in the B4 (non-self) and B12 (self) mating types. The synthetic PHBs also promoted the mating of two monokaryotic strains carrying B4-common incompatible mating types ($A5B4{\times}A1B4$). However, the dikaryon generated by this process exhibited abnormally high content of hyphal branching and frequent clamp connections and, more importantly, was found to be genetically unstable due to overexpression of mating-related genes such as clp1. Although synthetic PHBs were unable to discriminate self from non-self RCBs, they showed a higher affinity for non-self RCBs, through which the mating pheromone response pathway in non-self cells may be preferentially activated.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.217-231
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• 2020

In 2019, the sex pheromones of Spodoptera frugiperda were used to examine moth trapping in cornfields in Gochang, Korea. Four types of traps were prepared, two funnel-types and two delta-types, each baited with 300 or 1000 ㎍ of a two-component (2C) blend of synthetic sex pheromones [100% (Z)-9-tetradecenyl acetate (Z9-14Ac) and 2% (Z)-7-dodecenyl acetate (Z7-12Ac)]. The greatest number of S. frugiperda were captured in the 300 ㎍ funnel-type trap (first catch: August 6). Large numbers of Mythimna loreyi (a non-target) were also caught in the funnel-type traps. Two wing-type traps were baited with 1000 ㎍ of the 2C blend or a four-component (4C) blend [100% (Z)-9-tetradecenyl acetate, 8% (Z)-11-hexadecenyl acetate (Z11-16Ac), 2% (Z)-7-dodecenyl acetate, and 1% (Z)-9-dodecenyl acetate (Z9-12Ac)] and the capture efficiency was assessed. Low numbers of S. frugiperda were captured regardless of the blend, and more M. loreyi were captured using the 4C blend. The two intraspecies groups clustered separately in a phylogenetic tree constructed using partial sequences (1004 bp) of cytochrome c oxidase subunit 1 (CO1). Of the 70 S. frugiperda captured in the pheromone traps, 66 belonged to CO1-RS (CO1 rice-strain) and 4 to CO1-CS (CO1 corn-strain). Twelve consistent single nucleotide polymorphisms (SNPs) were identified in CO1 between the CO1-RS and CO1-CS groups of S. frugiperda. Of the 73 S. frugiperda, 4 had the same SNP pattern as the CO1-CS group (including the corn strain) and 69 had the same SNP pattern as the CO1-RS group (including the rice strain).

• Reproductive and Developmental Biology
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• v.29 no.1
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• pp.43-48
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• 2005

To search of a new porcine pheromonal odorants for biostimulation control system technologies to offer a potentially useful and practical way to improve reproductive efficiency in livestock species, the holographic quantitative structure activity relationship (HQSAR) model between odorants, 2-phenoxytetrahydrofurane (A), 2-cyclohexyl-oxytetrahydrofurane (B), derivatives and binding affinity constants (p[Od.]/sub 50/) for porcine odorant-binding protein (pOBP) as receptor of pig pheromones were derivated and disscused. The binding affinity constants of cyclohexyl substituents (A) for pOBP were higher (A>B) than that of phenyl substituents (B). It was revealed that the optimum HQSAR model XI using PLS analyses had a fragment length (5∼8) with chirality at 5 components and hologram length 97 bin, which had a cross-validated q²(predictablities) of 0.916, and a conventional correlation coefficient r² (fitness) of 0.988, respectively. From the atomic contribution, the C3 and C5 atom in 2-oxyfuryl group contributed to binding affinity constants, whereas the central carbon atom in tert-butyl group on the cyclohexyl ring and the C4 atom of furyl group parts showed no contribution.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.391-396
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• 2008

The pine sawyer, Monochamus saltuarius Gebler (Colepotera: Cerambycidae) was newly known as a vector of pinewood nematode causing the pine wilt disease in Korean white pine (P. koraiensis Siebold & Zucc.) forestry. Recently, it has a serious problem to spread fast and widely throughout Korea by transferring M. saltuarius. For the control of M. saltuarius, this study was investigated the attractants by analyzing from the Korean white pine. Major components of Korean white pine was analyzed as $\alpha$-pinene and ethanol, and reported as an attractant against Monochamus genus. Ipsenol and ipsdienol, the pheromones of Ips genus known as attractant components of woodboring beetles, were tested to the attractive efficacy against Monochamus saltuarius. The attractive efficacy showed 67.9% of Ipsenol plus ipsdienol and ipsenol, ipsdienol mixed with $\alpha$-pinene plus ethanol was showed 67.7% and 79.3%, respectively. Especially, ipsdienol with $\alpha$-pinene and ethanol was shown the high synergy effect, and the attractant effect was higher at M. saltuarius female than male.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.105-115
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• 2018

The comstock mealybug is one of the serious insect pest in pear. It is necessary effective control methods such as attractive sex pheromone. Using sex pheromones is necessary for studying the physiology and ecology of insect pests. In the present study, the sex pheromone of comstock mealybug was used for investigating the flying acts of the adult male. As temperature increased, the development period of eggs shortened, but it was longer at $30^{\circ}C$. The mean number of eggs laid was 482 at $25^{\circ}C$ and males constituted 37% of the experimental population at $30^{\circ}C$. The flight of the male comstock mealybug was mostly restricted to a 2-4 hour period after sunrise, even if condition of light period is changed. Male mealybugs were incapable of upwind flight towards an attractant when air velocity was 1.5 mph. Preference of height was tested in a pear orchard. The ineffective heights of the traps were 2 and 2.5 m, whereas the effective heights were 1 and 1.5 m. Many captured males at 0.5, 1, and 5 m, and the number of captured males were similar in 10, 15, and 20 m. Male mealybugs were captured up to a distance of 50 m, suggesting that it is possible to control the male mealybugs that are more than 50 m away when sex pheromone traps are used.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.67-72
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• 2009

The kairomonal activity of the aggregation pheromones of Riptortus clavatus for the egg parasitoid, Gryon japonicum, were investigated in soybean field. The parasitism rate of G. japonicum gradually decreased when the distances between pheromone traps and egg sites were increased from 0 to 15 m. The active distance of pheromone source for parasitoid attraction was estimated to be ca. 15 m. Under field conditions, the parasitoid wasp population peaked during the late August and early September, and the parasitism rate increased when the number of pheromone traps was increased from one to three per $165\;m^2$. However, insecticide-treated plots, the level of parasitism recorded is relatively low. Sex ratios in field populations of G. japonicum were female-biased.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.325-331
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• 2010

Attractiveness of stink bugs to various colors, heights and locations of fish-net traps incorporated with aggregation pheromones was determined. Bean bug, Riptortus pedestris Fabricius, was most attracted to yellow color trap, followed by white, black, green, blue and brown. R. pedestris and one-banded stink bug, Piezodorus hybneri Gmelin, were most attracted to fish-net traps placed 80 cm above the ground regardless of sexes of two species of stink bugs. Between the sexes, however, R. pedestris females were more attracted to 40 and 80 cm above the ground than the males at those heights although the attraction was not significantly different at 120 and 160 cm heights. P. hybneri females tended to be attracted to 40 and 80 cm height traps but the attraction was the opposite at 120 and 160 cm heights. The highest attraction of R. pedestris was observed in a perilla field with no significant difference in the soybean field and border area in which no crop were cultivated between the perilla and soybean fields. R. pedestris was also more attracted to the sweet persimmon orchard than the soybean and medicinal crops fields, which was a significant difference between the two fields.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.363-367
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• 2021

This study was conducted to investigate the EAG (electroantennogram) response of Spodoptera frugiperda male to sex pheromone compounds and whether or not S. frugiperda male adults would undergo double mating. The EAG response of S. frugiperda male adult to Z9-14:Ac increased in a dose-dependent as the dose increased. Among the 7 sex pheromone components investigated, male EAG recording was the highest to Z9-14:Ac. The EAG response of S. frugiperda male adult to the mixed sex pheromone component was greater than that to the single component. Male adults of S. frugiperda were capable of double mating under laboratory condition, and the secondary mating rate increased to 72.2% compared to the 58.3% of primary mating rate. The EAG response of mated S. frugiperda male adult was not different from that of unmated S. frugiperda male. In the net house test with sex pheromone lure, mated male adults were not captured during the test period. Also, strangely, unmated male adults were not captured even in a trap equipped with virgin female adults, although the antennae of mated male adult were responded to the sex pheromone component in the laboratory. Probably, it is thought that the mated male adults may not have been caught in the trap be due to flight ability which has been decreased after mating. The field attractiveness of S. frugiperda male adults to sex pheromones remains to be further elucidated.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.1-13
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• 2021

The concept of integrated pest management (IPM) first developed in the 1950s, and the concept of economic control via pest management was established in the 1960s. Research on IPM began in the United States and Europe, and IPM studies in Korea started with citrus insects and paddy field pests following the distribution of high-yield varieties of rice. Apple IPM in Korea began with research on pest control using chemical pesticides and pesticides resistant to insect pests, studies on the ecology of insect pests and their natural enemies, and the exploitation of sex pheromones on insect pests. Since the 1990s, IPM research and field projects have been carried out simultaneously for farming households. In the 2000s, the development of pest monitoring and forecasting models centered on mating disturbances, database programs for pests, and networks for sharing information. IPM technology has expanded via the development of unmanned forecasting systems and automation technologies in the 2010s.