The adult activity of M. alternatus caught in a pheromone trap showed a bimodal form consisted of the first peak in mid to late June and the second peak in mid to late September in Jeju area, Korea. The two peaks were separated apparently between mid and late August, showing a valley. The pine trees without oleoresin flow were abundant during early July to early August, and declined thereafter, which did not match with the valley of adult activity curve. Thus, the hypothesis that dying pine trees attract much strongly M. alternatus adults than that of pheromone lures may not fully explain the bimodal pattern, because the first adult activity peak occurred during the peak period of dying pine trees and it declined with decreasing dying pine trees. The accumulated degree-days showed that the emergence of the 2nd generation adults could occur before the second peak when the diapause ecology of M. alternatus was not considered. The voltinism of M. alternatus can affect basically the control strategy of this pest. Consequently, further studies are required to find out clearly the voltinism of M. alternatus in Korea.

The pheromone biosynthesis in Plutella xylostella is more active in the scotophase than in the photophase, indicating that there may be changes of gene expression in the pheromone glands. To identify genes contributing to change in pheromone production, we analyzed transcriptomes of pheromone glands from both decapitated females (PG-minus) in the photophase and normal ones (PG-plus) in the scotophase. Deep sequencing for mRNAs in the pheromone gland yielded approximately 7.5Gb and 6,671 transcripts showing positive FPKM value were analyzed. Differentially expressed gene analysis revealed that up- and down-regulated transcripts were 310 and 326 in the PG-plus transcriptome, respectively. Genes putatively involved in the pheromone biosynthesis pathway were identified such as acetyl-CoA carboxylase, acetyl-CoA dehydrogenase, fatty acid synthase (FAS), desaturases (Δ9 and Δ 11) and fatty acid reductases of pheromone gland (pgFAR), alcohol oxidase, aldehyde oxidase and aldehyde reductase, etc. Quantitative RT-PCR revealed that expressions of FAS, Δ11 desaturase and pgFAR were significantly higher in PG-plus, suggesting that they may have crucial roles in sex pheromone biosynthesis of P. xylostella

Pheromone biosynthesis activating neuropeptide (PBAN) produced in the suboesophageal ganglion stimulates pheromone biosynthesis in the pheromone gland, mediating sexual behaviors. Based on the transcriptome of the head, PBAN in the legume pod borer, Maruca vitrata, was identified. To examine the pheromonotropic activity of PBAN in the legume pod borer, Maruca vitrata, a PBAN (Mvi-PBAN) was synthesized. When female adults were injected with a synthetic Mvi-PBAN, pheromone production showed a maximal increase 2 h post-injection. PBAN was expressed in all examined tissues and developmental stages. In contrast, PBAN receptor (PBANr) was detected in the female tissues and all developmental stages except for adult male. In addition, two types of PBANr were identified from the transcriptome of the pheromone gland, suggesting that the molecular signal on the pheromone gland may transduce via PBANr.

Pheromone biosynthesis in the pheromone gland is stimulated by pheromone biosynthesis activating neuropeptide (PBAN) produced in the suboesophageal ganglion. PBAN binds its receptor and transduces biological signal into the molecules for the pheromone biosynthesis. To understand pheromone biosynthesis pathway in legume pod borer, Maruca vitrata, transcriptome of the pheromone gland was analyzed. A total of 191 contigs involved in the pheromone biosynthesis were identified. Putative pheromone biosynthetic pathways for sex pheromone components in M. vitrata were proposed through transcriptomic analysis.

Euzophera batangensis (Lepidotera: Pyralidae) is seriously damaging trunks or branches of persimmon tree (Diospyros sp.). We tested the attractiveness of (Z)-9-tetradecen-1-ol (Z9-14OH) and (Z9,E12)-tetradeca- 9,12-dien-1-ol (Z9,E12-14OH) with single or blended baits at southern parts of Korea in 2014 and 2015. The monoene was not attractive at all at three places during the two years. In 2014, diene was equally or more attractive than the mixture in Jinju and Suncheon, respectively. In 2015 too, the attractiveness of diene and mixture was not different in Jinju and Munsan. Monitoring of the seasonal occurrence of E. batangesis with the sex pheromone components revealed that it occurred three times a year; the first occurrence from early April to mid May, the second from early Jun to mid July, and the third from late August to late September.

A cDNA isolated from female adult heads of Maruca vitrata encodes 197 amino acids including PBAN. Synthetic Mav-PBAN induced pheromone production in the pheromone gland, indicating that this synthetic peptide was biologically functional. Expression of Mav-PBAN cDNA was found in all examined body parts whereas PBAN receptor only in the pheromone gland. Transcriptomic analysis revealed that 191 contigs involved in the pheromone biosynthesis such as PBAN receptor, PBAN, fatty acid transport proteins, acetyl-CoA carboxylases, fatty acid synthases, desaturases (FAD), β-oxidation enzymes, and fatty acyl-CoA reductases (FARs) were identified.

Pheromone biosynthesis activating neuropeptide (PBAN) produced in the subesophageal ganglion is known to stimulate pheromone production in the pheromone gland. A cDNA isolated from female adult heads of Maruca vitrata encodes 197 amino acids including PBAN, designated as Mvi-PBAN, and four other neuropeptides (NPs): diapause hormone (DH) homologue, α-NP, β-NP and γ-NP. All of the peptides are amidated in their C-termini and shared a conserved motif, FXPR(or K)L-NH2 structure. Mvi-PBAN consists of 35 amino acids as previously reported (Chang and Ramasamy, 2014). RT-PCR analysis revealed that Mvi-PBAN cDNA was expressed in all examined body parts. Nucleotide sequence analysis of RT-PCR products indicated the Mvi-PBAN sequence was identical in all examined body parts of both sexes. These results suggest that Mvi-PBAN expression is maintained in examined stages or tissues.

Pheromone biosynthesis-activating neuropeptide (PBAN), produced in subesophageal ganglion, is known to stimulate pheromone biosynthesis in Plutella xylostella. The pheromone production is more active in the scotophase than in the photophase, which suggests that there may be changes of gene expression in the pheromone glands. To analyze gene expression involving in pheromone biosynthesis for 24 hrs, we performed transcriptomes of pheromone glands which were isolated at every 4 h. Eleven pheromone biosynthesis-related genes, acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), acyl-CoA dehydrogenase, enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase, Δ9 desaturase, Δ11 desaturase, fatty acid reductase (FAR), alcohol oxidase, aldehyde oxidase, and aldehyde reductase were identified. Among these genes, ACC, FAS and chain shortening enzymes involving in early stage of pheromone biosynthesis exhibited their highest expression between AM9 and PM5. Desaturases, Δ9 and Δ11, showed the peak of expression at PM1 and AM5 or PM5, respectively. Interestingly, FAR expression was the highest at AM1, active reproductive period. These results suggest that genes involving in pheromone biosynthesis can be sequentially regulated for their biological roles.

Six wooden plant essential oils (EOs; Illicium verum, Gaultheria fragrantissima, Bursea delpechiana,Croton anisatum, Cinnamomum cassia and Aniba rosaeodora) and their major compounds (trans-anethole, methyl salicylate, trans-cinnamaldehyde, linalool and linalyl acetate) identified from gas chromatography (GC) and GC-mass spectrometry were tested for adult repellence and pheromone antagonism using Y-tube essay and oviposition deterrent effect using no choice test against adzuki bean beetle (ABB), Callosobruchus chinensis L. EOs of I. verum and C. anisatum as well as their common major compound, trans-anethole were found effective repellents having high degree of pheromone antagonistic and oviposition deterrent activity. Methyl salicylate, the major compound of G. fragrantissima EO (which was only the pheromone antagonist) showed high degree of repellency, oviposition deterrence and pheromone antagonistic effect in higher concentration. From this study, EOs of I. verum and C. anisatum and their common major compound trans-anethole as well as the major compound of G. fragrantissima, methyl salicylate can be screened as eco-friendly management agents against C. chinensis in stored legumes if slow releasing formulations are prepared by future efforts.

Two Grapholita congener, G. molesta and G. dimorpha have difference in several biological characters such as flight time, emerging number/year, damage site, pupation site, and mating time although their host plants were similar. As a problem, cross-trapping was identified in each trap for monitoring. Effects on species-specific lure using minor sex pheromone components were observed in host plant orchards (apple, pear, peach, and plum) for continuative two years. Treatments of various ratios (0 to 10%) of Z8-12OH to G. molesta lure (Z8-12Ac/E8-12Ac = 95:5) allowed to increase the attraction of G. molesta, but not of G. dimorpha male. Other two minor components (14Ac and 12Ac) to G. dimorpha lure (Z8-12Ac/E8-12Ac = 85:15) were not showed species-specific responses. However, 10% treatment of Z8-14Ac to G. dimorpha lure was showed that G. molesta was decreased significantly although G. dimoprha was not affected. E8-14Ac treatment to new G. dimorpha lure (Z8-12Ac/E8-12Ac/Z8-14Ac = 85:15:10) not affected to attraction of two species. From these results, we suggest that optimum ratios for species-specific monitoring of G. molesta and G. dimorpha are Z8-12Ac/E8-12Ac/Z8-12OH = 95:55:5 and Z8-12Ac/E8-12Ac/Z8-14Ac = 85:15:10, respectively.

Behavioral responses to the sex pheromone blends rely on genetically designed hardwired olfactory pathways, including precise detection of the specific pheromone compounds and sophisticated signal processes in the brain to interpret correct pheromone mixture information. Owing to minimized association of individual variation and acquired traits from learning in sex pheromone communication, behavioral assays can be very useful tool for understanding each step in the olfactory system. To investigate interactions between peripheral and central pathways in shaping olfactory perception, we used antennal imaginal disc transplants between phylogenetically close two heliothine moth species Heliothis virescens and Heliothis subflexa. In behavioral tests, the response patterns of the male transplants were distinct from any of normal males of either species. Neurophysiological analyses of olfactory receptor neurons in the antenna and projection neurons in the brain also supported the behavioral dissimilarities between the transplants and normal animals. Results will be discussed in light of the functional roles and developmental significances of peripheral and central olfactory pathways in pheromone communication system.

벼룩잎벌레(Phyllotreta striolata)와 무잎벌(Athalia rosae ruficornis)는 제주지역 무에서 돌발적으로 발생하여 피해를 주는 해충이다. 본 연 구는 벼룩잎벌레와 무잎벌 성충의 트랩 색(황색과 청색)과 벼룩잎벌레 집합페로몬(+)-(6R,7S)-himachala-9,11-diene과 기주식물 휘발성 물질 인 allyl isothiocyanate의 혼합물을 이용 두 해충의 발생을 간편하게 예찰하는 방법을 개발하기 위하여 수행하였다. 벼룩잎벌레는 트랩 색에 관 계없이 집합페로몬이 부착된 점착트랩에 더 많은 성충이 유인되었으며, 무잎벌은 황색점착트랩이 청색트랩보다 더 많이 유인되었고 벼룩잎벌레 집합페로몬은 유인량에 관계가 없었다. 따라서 벼룩잎벌레 집합페로몬을 부착한 황색점착트랩을 이용하면 벼룩잎벌레와 무잎벌 성충 발생을 효 율적으로 예찰할 수 있었다. 점착트랩의 높이는 기주식물에 가까울수록 두 해충의 유인수가 많아 기주식물 상단 10 cm 높이로 설치하는 것이 좋 을 것으로 판단되었다. 벼룩잎벌레와 무잎벌의 연간 발생피크는 각각 3회와 5회정도 나타났으며, 두 해충의 첫 주발생시기는 벼룩잎벌레는 3월 중하순, 무잎벌은 4월 중하순이었다. 벼룩잎벌레와 무잎벌 성충의 연간 발생특성을 이용하면 두 해충의 무에서의 피해를 최소화하는데 중요한 정 보로 활용될 것으로 기대된다.

The longhorn pine sawyers, Monochamus saltuarius and M. alternatus (Coleoptera: Cerambycidae), are vectors of the pinewood nematode Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae), the causal pathogens of pine wilt disease in Korea. Recently, an aggregation pheromone, 2-(undecyloxy)ethanol, identified from M. galloprovincialis and M. alternatus, was shown to be effective for attracting several Monochamus species in Europe, North America, and East Asia. However, the effect of 2-(undecyloxy)ethanol on attracting M. saltuarius remains largely unraveled. In this study, we investigated the abilities of 2-(undecyloxy)ethanol along with host plant volatiles (α-pinene and ethanol) to attract M. saltuarius at a pine forest in Cheongsong, Gyeongsangbuk-do, Korea. Pine trees in the field experiment site were not previously affected by pine wilt disease. The combination of 2-(undecyloxy)ethanol with host plant volatiles was more effective than either of 2-(undecyloxy)ethanol or host plant volatiles for attracting M. saltuarius. Both sexes of M. saltuarius were attracted to traps containing 2-(undecyloxy)ethanol with the host plant volatiles. Our study suggests that the aggregation pheromone in combination with host plant volatiles could be used for detection and population monitoring of M. saltuarius as well as for effective mass trapping in outbreak situations.

The Citrus Leafminer (CLM) larvae creates shallow tunnels in leaves of citrus (orange, mandarins, lemons, grapefruit, etc) and commonly attacks citrus young leaves. They spread almost worldwide (North America, Asia, Australia, etc) and difficult to control by chemicals due to their small size and their behavior of leaf rolling. Due to difficult of managing, our interest is preparing pheromone to control; Z7Z11-16;Al is known as the sex pheromone of this species in Japan. While blending Z7Z11-16;Al and Z7Z11E13-16;Al (3:1 ratio) is known as the pheromone of this insect in North America. Even though commercialized and mass produced already in overseas, there had been almost no report in Korea about synthetic studies and field screening results. The control of the regio-isomers is very important in this kind of pheromone synthesis. Our strategy is the regio-selective Wittig olefination reaction between E-pent-2-enyl(triphenylphsphonium)bromide (phosphonium salt) and the counterpart aldehyde using sodium hexamethyldisilazide (NaHMDS) as a base. All the spectroscopic data (1H, 13C, GC-Mass, etc) are nicely matched with the previously reported values. The field screening in the Jeju island is currently ongoing and will be reported.

The pheromone biosynthesis in Plutella xylostella is stimulated a neuropeptide, pheromone biosynthesis activating neuropeptide which is produced in subesophageal ganglion. The pheromone production is more active in the scotophase than in the photophase, which suggests that there may be changes of gene expression in the pheromone glands. To analyze gene expression related to pheromone biosynthesis, we performed transcriptomes of pheromone glands which were isolated at every 4 h. Eleven pheromone biosynthesis-related genes, acetyl-CoA carboxylase, fatty acid synthase, acyl-CoA dehydrogenase, enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase, Δ9 desaturase, Δ11 desaturase, fatty acid reductase, alcohol oxidase, aldehyde oxidase, and aldehyde reductase were identified. Among these genes, the expression of aldehyde reductase and aldehyde oxidase were relatively higher in the scotophase than in photophase, which may affect increase of pheromone production in the scotophase. Expression of signal genes involving in pheromone biosynthesis such as acyl-CoA desaturase, FAR, PBAN receptor, fatty acid transporter and acyl-CoA binding protein did not exhibited any significant difference.

Athetis dissimilis (Hampson) (Lepidoptera: Noctuidae) [뒷흰날개담색밤나방] was attracted to pheromone traps for Euzophera batangesis (Lepidoprera Pyrimidae) [밤알락명나방], when occurrence of E. batangesis was monitored in sweet persimmon orchard with its pheromone, (Z)-9-tetradecenol (Z9-14OH), (Z9,E12)-9,12-teradecadienol (Z9,E12-14OH) and their mixture. With the components, we monitored the seasonal occurrence of A. dissimilis, tested response of the moth to single or mixed components, and compared efficacy of three different types of traps. A. dissimilis was trapped on May 14 for the first time. First occurrence peak was observed during June 4-24 and second peak during August 20 – September 10. A. dissimilis was attracted to single component of Z9-14OH and Z9,E12-14OH and to their mixture at Jinju, Sancheong, and Sacheon. In trap efficacy tests, delta traps with white color caught most number of the moths significantly at Sacheon. However, at Sancheong, there was no statistical difference among the traps, although funnel trap caught most number of A. dissimilis. Pest status of A. dissimilis is not known eg. whether it is a pest of persimmon or other fruits. However, with Z9-14OH, E9,E12-14OH and their mixture, it is expected to be monitored and controlled.

Riptortus pedestris (F.) (Hemiptera: Alydidae) is an important pest of soybeans in Korea and Japan. A synthetic aggregation pheromone trap has been commercialized and used in soybean fields in Korea for both monitoring and mass-capture of this bug. As the trap’s efficacy in reducing the pest population or crop damage is unknown, in this study we evaluated the aggregation pheromone trap in experimental soybean fields located in Andong National University. Two treatments, one with traps deployed for the entire cultivation period and one with no traps, were tested in six small experimental fields. The total numbers of R. pedestris (in all life stages) in soybean field were not significantly different between the treatments until August. But, in presence of pheromone, the pest’s abundance increased significantly in September and October. Relative to the size of the bug population in the field, trap catch rate was low during the fall (when bug density was highest) and high in early summer when the field population was very low. Placement of aggregation traps in plots caused pod and seed damage from R. pedestris to increase 2.7 and 2.2 times compared to the control. In conclusion, R. pedestris populations increased significantly during the fall in the presence of the aggregation pheromone trap, which should therefore be used with great caution whether as a control measure or as a monitoring tool.

The pine wilt disease that blocks the path for water and nutrition in pine trees is caused by the nematode, Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae). The nematode relies on the longhorn pine sawyer beetle Monochamus alternatus and Monochamus saltuaris (Coleoptera: Cerambycidae) as vectors. Recently, 2-(undecyloxy)ethanol was identified as a male-produced aggregation pheromone of Monochamus species. In this study, we investigated the effect of 2-(undecyloxy) ethanol along with host plant volatiles -pinene and ethanol on attracting M. alternatus at a pine forest in Pohang, Korea from May, 2014 to July, 2014. To sustain the volatility of 2-(undecyloxy)ethanol and host plant volatiles, a superabsorbent polymer based on polyacrylic acids and water were added to the pheromone mixture. A total of 46 M. alternatus were collected from two field bioassays. Our results indicate that 2-(undecyloxy)ethanol is effective in attracting M. alternatus in Korea. Our study suggests that the aggregation pheromone could be used for detection and population monitoring of the beetles as well as for the effective mass trapping in outbreak situations.

Insect pests on cruciferous crops and their natural enemies were surveyed during 2009~2011 in Daegwallyeong highland region which has been famous for summer Kimchi cabbage production in Korea since 1970s. Totally 15 insect pests have been reported in cabbage field in Daegwallyeong. Diamondback moth (DBM, Plutella xylostella) imported cabbage worm (Artogeia rapae L.), cabbage armyworm (CAW, Mamestra brassicae L.), cabbage looper (CL, Trichoplusia ni), cabbage sawfly (Athalia rosae ruficornis Jakovlev), and turnip aphid (Liphapis pseudobrassicae (Davis)) were the dominant pest species among the 15 species. For monitoring as well as controlling insects with weak flight, yellow sticky cards (10×15㎝) were used in cabbage fields. The sticky cards were hanged on plastic stick and placed at a 2-5 m distance within cabbage field (1,000㎡). Sex pheromone traps were employed for monitoring and controlling insects with strong flight. The survey result showed that there was significantly reduced pest occurrences in treated, compared to untreated condition. Similarly, The results from the sex pheromone traps were coincident with those of sticky trap. DBM, CAW and CL were found less in the treated than untreated fields; by 67.5%, 70.6% and 44.0%, respectively. Although the control efficacy of such traps was less than that of chemical spray, the use of sticky card trap combined with sex pheromone trap could be useful management tools for controlling insect pests in cabbage fields.

The pheromone biosynthesis in Plutella xylostella is more active in the scotophase than in the photophase, which suggests that there may be changes of gene expression in the pheromone glands. To identify genes contributing to change in pheromone production, we analyzed transcriptomes from pheromone glands of both decapitated females in the photophase and normal ones in the scotophase. Comparative analysis were performed with transcriptomes of pheromone glands from non-decapitated (PG) females and decapitated ones for identification and expression of putative genes associated with pheromone biosynthesis pathway. Deep sequencing for mRNAs in the pheromone gland yielded approximately 7.5Gb and totally 17265 transcript were constructed under a homology cutoff of 10-6 Evalue. Genes putatively involved in pheromone biosynthesis were identified such as acetyl-CoA carboxylase, acetyl-CoAdehydrogenase, fatty acid synthase (FAS), desaturases (Δ9 and Δ 11) and fatty acid reductases (FAR) including pgFAR, alcohol oxidase, aldehyde oxidase and aldehyde reductase, etc. Expression of 6 signal genes involving in pheromone biosynthesis such as acyl-CoA desaturase, FAR, PBAN receptor, fatty acid transporter, acyl-CoA binding protein did not exhibited ant significant different in both transcriptomes. Quantitative RT-PCR revealed that expressions of FAS, Δ11 desaturase and pgFAR were higher in PG than that in ΔPG. Based on results, Δ11 desaturase and pgFAR may have a crucial role in sex pheromone biosynthesis of P. xylostella.