• Korean journal of applied entomology
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• v.34 no.1
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• pp.9-14
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• 1995

From a chemist's perspective, Scarabaeidae is one of the most exciting group of insects to work on the isolation, identification, and synthesis of sex pheromones because-as opposed to Lepidoptera, which by and large utilizes straight chain alcohols, aldehydes, and acetates-the pheromonal chemistry of scarab beetles is remarkably diverse. While species in the subfamily Rutelinae utilize pheromone constituents, which are presumably fatty acid derivatives, the more primitive species in the subfamily Melolonthinae use phenolic, amino acid derivative, and terpenoid compounds. Here, I discuss the recent advances we have accomplished in the identification of scarab sex pheromones with especial emphasis on their chemical diversity. Also, I discuss the potential role of these sex pheromones in insect pest management. Field tests revealed that, in contrast to what has been frequently observed in the Lepidoptera, the higher the dosage of sex pheromone loaded in the traps the greater the capture of scarab beetles. These data suggest that mass trapping is more likely to be useful for scarab pest management than mating distruption.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.61-67
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• 2017

Two major sex pheromone components (Z-8-dodecenyl acetate and E-8-dodecenyl acetate) are known in the peach fruit moth, Grapholita molesta. From a putative biosynthetic pathway of these sex pheromone components, delta 10 desaturase ($10{\Delta}$ DES) has been proposed to play a crucial role in synthesizing a species-specific stereoisomer of the double bond. However, its molecular identity was not known. This study determined a putative desaturase (Gm-comp1575) as a $10{\Delta}$ DES candidate from G. molesta transcriptome constructed from the sex pheromone gland. Its open reading frame encodes 370 amino acid sequence with a predicted molecular weight at 43.2 kDa and isoelectric point at 8.77. It was predicted to have four transmembrane domains and six glycosylation sites at N-terminal or cytosolic domains. A phylogenetic analysis with its predicted amino acid sequence indicated that Gm-comp1575 is closely related with known $10{\Delta}$ DES genes of other insects. Gm-comp1575 transcript was detected in female adults at sex pheromone gland and other abdominal tissues. RNA interference of Gm-comp1575 significantly reduced attractiveness of virgin females in apple orchard compared to control females. These results suggest that Gm-comp1575 is associated with sex pheromone biosynthesis of G. molesta.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.393-398
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• 2020

The blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on cultivated blueberries in Korea. To develop a sensitive tool for monitoring this pest in blueberry orchards, we compared the attractiveness of host plant volatiles and sex pheromone to D. oxycoccana adults. We performed gas chromatography-mass spectrometry (GC-MS) analysis of solid-phase microextraction (SPME)-collected volatiles that were released from blueberry ('Darrow' cultivar). The analysis revealed two major volatiles, cinnamaldehyde and cinnamyl alcohol from flowers; and three major volatiles, β-caryophyllene, germacrene D, and α-farnesene from shoots and young fruits. In field tests conducted in Gunsan, Korea in 2019, commercialized cinnamaldehyde, cinnamyl alcohol, β-caryophyllene, and α-farnesene, used singly or in quaternary combination, were unattractive to the blueberry gall midge. However, traps baited with the known sex pheromone (2R,14R)-2,14-diacetoxyheptadecane attracted significantly more males than the treatments with plant volatiles or the control. No synergistic effect was observed between sex pheromone and plant volatiles. Male D. oxycoccana were captured in the pheromone traps from May to August, with three peaks in mid-May, late June, and late July in Gunsan blueberry fields in 2020.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.245-257
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• 2018

The efficacy of different control techniques against the large black chafer, Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae), in organic pear (Pyrus pyrifolia) orchards was evaluated. In this study, field trials were conducted in three locations in Korea-Naju, Hampyeong, and Boseong-to evaluate different techniques to suppress these beetles. Pheromone traps, bio-insecticides (Hongmengye and Melchungdaejang), and a combination of the two were applied as treatments. In Naju, Hampyeong, and Boseong, the highest number of adult H. parallela were caught in the control plots (n=45, n=39, and n=20, respectively), while the fewest were caught in the pheromone plus bio-insecticide plot (n=19) in Naju and in the combined treatment plot in Hampyeong (n=10). In Naju, the greatest leaf damage was observed in the control (66%), and in all locations (Naju, Boseong, and Hampyeong), the least damage occurred in the combined treatment plots (42%, 36%, and 24%, respectively). Regarding the tree canopy, the greatest leaf damage was observed in the upper canopy, and less damage was observed in the lower canopy. These results demonstrate that the combination of sex pheromone traps and bio-insecticides can be used to manage H. parallela in organic pear orchards.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.169-173
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• 1995

This study was conducted to investigate control effects against Spodoptera exigua Hubner in field using mating disruption dispensers of synthetic sex pheromone during 1993 and 1994. Denisities in egg and larva of Spodoptera exigua in field treated with the dispensers was 1.9% level of that without dispensers in welsh onion, 12.5% in red pepper and 4.4% in potato in 1993. Also 5.9% and 5.2% were counted from 10 ha and 20 ha of welsh onion field compared. Control value in Fields with dispensers were maintained at 80% level in 10 ha and 90% level in 20 ha until October.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.15-28
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• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.94-99
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• 1991

The daily rhythm of sex pheromone production and release by females of the black pine base scale, Matsucoccus thunbergianae Miller and Park, was demonstrated by studying the amounts of pheromone possessed and released by females, periodically after emergence. Cycles of both pheromone production and release had daily peaks between 8 a.m. and 2 p.m., and has marked decreases after 4 p.m. It appeared that the amounts of pheromone gradually decreased three days after the emergence. Significance in synchronization of the daily rhythm of female pheromone release and activities of males and females with reference to reproductive success in this species is discussed.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.341-348
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• 2013

We desinged and evaluated a remote-sensing sex pheromone trap for real-time monitoring of Mythimna separata (Lepidoptera: Noctuidae), a migratory insect in Korea. The system consisted of a modified cone-trap with a sex pheromone lure, a sensing module based on light interruption, a signal transmission module based on code division multiple access, a main electronic board for system control, a power supply based on a solar collector, a stainless steel-pole supporting the system, and a signal collection and display system based on an internet web page. The ratio (>92%) of the actual number of insects to the signal number in the remote-sensing trap was improved by sensing only within a limited period at night on the basis of the insect's circadian rhythm, control of signal sensitivity on the basis of sensing software programming, 1-h interval for signal transmission, and adjustment of the signal transmission program. The signal occurrence pattern in the remote-sensing trap was conclusively similar (correlation coefficient, >0.98) to the actual pattern of adult occurrence in the trap. The result indicated that the remote-sensing trap based on the attraction of the sex pheromone lure for M. separata has a promising potential for practical use. Occurrence of M. separata adults was observed several times in 2011 and 2012, and the peaks were sharp.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.323-330
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• 1997

The apple leafminer, Phyllonorycrer ringoniella (Lepidoptera: Gracillariidae), is the most important pest on apple leaves and is not easy to be controlled with insecticides because of leafmining habit of its larvae. This study was undertaken to develop an artificial diet for mass rearing of the moth, and to look at their reproductive behavior. For developing an artificial diet the problem of diet contamination with microorganisms and how to supply artificial diet to first instar larvae have to be solved first. Artificial oviposition trial was successful with shadowy bottomside of various papers sprayed with apple leaf extracts. The highest activity of both calling and mating was observed within 30 min. after the onset of photophase and 3- to 4-day -old adults showed the highest mating rate. A ring-shaped sex pheromone gland was found at the intersegmental membrane between the 8th and 9th abdominal segments of the female. (E, 2)-4,lOtetradecadienyl acetate was identified as the major component from the femall gland extracts by the gas chromatography (GC) and GC-mass spectrometry. Additionally it was thought that (a-10-tetradecenyl acetate could be the second component of their sex pheromone.

• Korean journal of applied entomology
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• v.51 no.3
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• pp.207-213
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• 2012

The cryptic mealybug, Pseudococcus cryptus, has been increasingly damaging citrus, particularly those plants grown in plastic greenhouses. This study was conducted to monitor the seasonal phenology of adult male cryptic mealybugs and to determine the timing for control using a sex pheromone trap. Adult males responded to a synthetic sex pheromone and trap color. An increasing number of males were attracted to the traps with increasing concentrations of sex pheromone up to 5 mg. The males occurred annually four times and had three cohorts at a time due to different overwintering developmental stages. After overwintering the adult males began to in mid-late April. A positive correlation was observed between the number of adult males caught in traps and the mean density per twig of all motile stages except first stage nymphs of the cryptic mealybugs. The peak time for the first nymph to occur was estimated from the maximum attraction time of the males, and the cumulative degree days (DD) was 350 DD, similar with the preoviposition period.