Electroantennogram and field responses of Korean population of the rice leaf folder,Cnaphalocrocis medinalis (Lepidoptera: Crambidae), to sex attractant candidates

A series of studies was conducted to determine the optimum sex attractant for monitoring the rice leaf folder, Cnaphalocrocis medinalis, in Korea, based on the previously reported pheromone composition in this species. (Z)-13-Octadecenal (Z13-18:Al) was most active in electroantennogram (EAG) and field tests. (Z)-11-Hexadecenal (Z11-16:Al), (Z)-11-octadecenal (Z11-18:Al), (Z)-11-hexadecenyl acetate (Z11-16:Ac), (Z)-13-octadecenyl acetate (Z13-18:Ac) and (Z)-13-octadecenol (Z13-18:OH) individually elicited significant EAG responses, but were not individually attractive in field trials. (Z)-11-Octadecenol (Z11-18:OH) alone was inactive in both EAG and field tests. The addition of Z11-18:OH and Z13-18:OH to the binary mixture of Z11-18:Al and Z13-18:Al, as the previously reported composition of the Japanese blend, significantly increased the trap catches of males in field trials. In contrast, the Philippine and Indian blends were not attractive to this species. Interestingly, when Z13-18:Ac alone was added to the binary mixture of Z11-18:Al and Z13-18:Al, the trap catch number was the same as that of the Japanese blend. The present study indicates that the four-component blend (Z11-18:Al/Z13-18:Al/Z11-18:OH/Z13-18:OH = 11/100/24/36) and the three-component blend (Z11-18:Al/Z13-18:Al/Z13-18:Ac = 11/100/11) can be used as sex attractants for monitoring the Korean populations of C. medinalis.     

Identification and application of the sex pheromones of the rice green caterpillar Naranga aenescens in Korea

This study was carried out to investigate the optimum composition of sex pheromones for mate attraction in the rice green caterpillar Naranga aenescens, and to evaluate the effects of pheromone quantity, trap type, and trapping location on trapping success in Korean paddy fields. Mating rate of N. aenescens increased with age, with the highest mating rate 2 days after emergence. The highest mating rate occurred within 1 h after lights-off; mating pairs were not observed during the photophase. In electroantennogram (EAG) and gas chromatography with electroantennographic detection (GC–EAD) analysis, virgin female extracts had 2 EAD-active components. The mass spectra of the 2 distinct EAD-active components were identical to those of Z9-14:Ac and Z11-16:Ac. Additionally, Z9-16:Ac was identified in the extracts in gas chromatography–mass spectrometry (GC–MS) analysis. Wing traps with lures containing 1 mg of a 2:1:4 mixture of Z9-14:Ac, Z9-16:Ac, and Z11-16:Ac was the most attractive to N. aenescens males. Pheromone-baited wing trapping, therefore, can be a simple and effective tool for monitoring N. aenescens populations.     

Field trials of synthetic sex pheromone lures for the large cabbage-heart caterpillar moth, Crocidolomia pavonana (Lepidoptera: Crambidae) in Indonesia

The efficacy of synthetic female sex pheromone lures for Crocidolomia pavonana (Fabricius) (Lepidoptera: Crambidae) in the cabbage fields of Java and Bali, Indonesia, was investigated by varying the composition and dosage of the components. The lure containing a synthetic pheromone blend of (Z)-11-hexadecenyl acetate (Z11–16: Ac) and (Z)-9-tetradecenyl acetate (Z9–14: Ac) at a 10:1 ratio acquired significantly more male catches than single component lures and the control lure. Meanwhile, no attraction was observed when lures with 1:1 and 1:10 blends were tested. The composition of Z11–16: Ac and Z9–14: Ac at a ratio of 5, 10 and 20:1 attracted more males than the control lures. Dosage studies showed that 0.055 and 0.55 mg of a mixture of Z11–16: Ac and Z9–14: Ac (10:1 ratio) attracted more males than the control. These results are the first demonstration of the efficacy of synthetic pheromone for C. pavonana in field conditions. The present study suggests the feasibility of pheromone-based monitoring as a simple and low-cost technique for integrated pest management of this pest.     

Antagonistic Effect of (Z)-11-Hexadecen-1-ol on the Pheromone-Mediated Flight of Helicoverpa zea (Boddie) (Lepidoptera:Noctuidae)

Flight-tunnel experiments were conducted using Helicoverpa zea males to determine whether or not (Z)-11-hexadecen-1-ol (Z11-16:OH), a compound emitted by another heliothine moth species, Heliothis subflexa, is a behavioral antagonist when admixed with the two-component pheromone blend of H. zea. Males were less likely to fly upwind all the way to the source when 0.3% Z11-16:OH was present in the blend. Even 0.1% Z11-16:OH caused differences in the flight behavior of H. zea males; they steered more off the windline than males responding to the pheromone blend alone, resulting in more oblique track angles. Thus Z11-16:OH appears to act antagonistically, along with another compound, (Z)-11-hexadecen-1-ol acetate (Z11-16:Ac), when it is added to the H. zea pheromone blend.     

Female sex pheromone components of the box tree pyralid,Glyphodes perspectalis,in Korea: Field test and development of film-type lure

The box tree pyralid, Glyphodes perspectalis, is the most destructive pest of the box tree in Korea and was recently introduced into Europe. The previously known as EAG active components of this moth, (Z)-11-hexadecenal (Z11-16:Ald), (E)-11-hexadecenal (E11-16:Ald), and (Z)-11-hexadecenol (Z11-16:OH) have been detected from the extracts of female abdomen. The ratios of these three compounds identified in female moth were 5.2:1:0.2 in 2010 and 6.5:1:0.2 in 2011. During field bioassays, it was found that the male moths were not attracted to Z11-16:Ald or E11-16:Ald when used alone; however, they were attracted to a mixture of the above. The most effective ratios of Z11-16:Ald to E11-16:Ald were 5:1 and 7:1. A small amount of Z11-16:OH inhibited male moth attraction in field bioassays. Further, a uni-trap was found to be more effective in catching the moth than delta and wing traps were. In field bioassays using 2 different types of lures, significantly more male G. perspectalis were caught to film-type lures (50.5 ± 4.4/trap) than those to rubber septum lures (35.8 ± 5.2/trap).     

Sex pheromone of the African armyworm <Emphasis Type="Italic">Spodoptera exempta</Emphasis> (Lepidoptera: Noctuidae): identification of components of the Okinawan population and formulation for population monitoring

In 2010, abrupt outbreaks of the African armyworm, Spodoptera exempta (Walker), occured on the Tarama, Iriomote and Kikai Islands in southwestern Japan. Analysis by gas chromatography-electroantennographic detection (GC-EAD) revealed two EAG-active compounds on male antenna in crude extract of virgin females. These compounds were identified as (9Z)-9-tetradecenyl acetate (Z9-14:Ac) and (9Z,12E)-9,12-tetradecadienyl acetate (Z9E12-14:Ac) in ca. 90:10 ratio by subsequent GC-MS analyses. (11Z)-11-Hexadecenyl acetate (Z11-16:Ac), which had previously been identified as a third component in the Kenyan population, was not detected. Binary blends of Z9-14:Ac and Z9E12-14:Ac at ratios between 99:1 and 90:10 showed a potent attractiveness in the field, superior to that of virgin females and comparable to that of the three-component formulation determined in Kenya. For the population survey, a 98:2 blend was used. In Tarama, only a few moths of S. exempta were captured with a light trap during the night when more than 600 males were captured with synthetic sex pheromone; more S. exempta captures with a light trap had been reported than with sex-pheromone traps in Kenya. This indicates that the Okinawan population has different properties from the Kenyan population in pheromone composition and behavioral response to light.     

Effect of (E4, Z6)-4,6-Hexadecadienal in attraction of Stathmopoda masinissa with its pheromone components of Korean population

Timely insecticidal application for Stathmopoda masinissa Meyrick (Lepidoptera: Stathmopodidae), is important, for reducing damage to persimmon (Diospyros kaki Thunb.), an important tree fruit cultivated in Korea. In this regard, the early and precise detection of adult S. masinissa is desirable. In this study, we report the effect of (E4,Z6)-4,6-hexadecadienal (E4,Z6-16Ald) with sex pheromone components in attracting S. masinissa males. The sex pheromone of S. masinissa in the Korean population comprised two components, (E4,Z6)-4,6-hexadecadienyl acetate (E4,Z6-16Ac) and (E4,Z6)-4,6-hexadecadienol (E4,Z6-16OH). It was shown that the E4,Z6-16Ald acts as a synergist of E4,Z6-16Ac for attracting S. masinissa in the Japanese population. To test whether E4,Z6-16Ald could be used as an attractant in the Korean population, the E4,Z6-16Ald with the two pheromone components was evaluated in attracting S. masinissa males. Electroantennography (EAG) assays were performed to determine the antennal responses of S. masinissa males to the two pheromone components and E4,Z6-16Ald tested. A field attraction test with a combination of pheromones and E4,Z6-16Ald was carried out for 3 years in three different regions in Korea. E4,Z6-16Ald elicited as high a response as the two pheromone components. A mixture of the two pheromone components and E4,Z6-16Ald and a mixture of E4,Z6-16Ac and E4,Z6-16Ald attracted more S. masinissa males than a mixture of E4,Z6-16Ac and E4,Z6-16OH, the pheromone of Korean population. This new pheromone lure formulation with E4,Z6-16Ald is expected to contribute to the precise detection of S. masinissa by luring males to pheromone-baited traps.     

Synthesis of (Z)-2-((1H-indazol-3-yl)methylene)-6-[11C]methoxy-7-(piperazin-1-ylmethyl)benzofuran-3(2H)-one as a new potential PET probe for imaging of the enzyme PIM1

(Z)-2-((1H-Indazol-3-yl)methylene)-6-methoxy-7-(piperazin-1-ylmethyl)benzofuran-3(2H)-one is a potent and selective proviral integration site in moloney murine leukemia virus kinase 1 (PIM1) inhibitor with an IC₅₀ value of 3 nM. (Z)-2-((1H-Indazol-3-yl)methylene)-6-[¹¹C]methoxy-7-(piperazin-1-ylmethyl)benzofuran-3(2H)-one, a new potential PET probe for imaging of the enzyme PIM1, was first designed and synthesized in 20–30% decay corrected radiochemical yield and 370–740 GBq/μmol specific activity at end of bombardment (EOB). The synthetic strategy was to prepare a carbon-11-labeled Boc-protected intermediate followed by a quick acidic de-protection.     

Male and female Popillia quadriguttata (Fabricius) and Protaetia brevitarsis (Lewis) (Coleoptera: Scarabaeidae) response to Japanese beetle floral and pheromone lures

Popillia quadriguttata (Fabricius), and Protaetia brevitarsis (Lewis) adults were captured with Japanese beetle, Popillia japonica Newman, sex attractant and floral lures at Changchun, China during July–August 2012. The floral lure (phenethyl propionate:eugenol:geraniol, 3:7:3) was attractive to male and female P. quadriguttata (AV: 1.2 ± 0.9; 1.1 ± 0.3; total: 2.3 ± 0.8), and was similar in attraction to the combination of the sex attractant (SA) [(R, Z)-5-(1-decenyl) dihydro-2(3H)-furanone] plus the floral lure for male (1.60 ± 0.2), female (1.30 ± 1.1) and total captures (2.9 ± 3.0). However, the SA alone captured only males in much higher numbers than when combined with the floral lure (10.0 ± 6.4). In a separate earlier test, the greatest number of P. quadriguttata males (12.5 ± 3.0), female (12.2 ± 1.5) and total captures (24.7 ± 2.5) was in yellow, laboratory-made, bottle traps. The floral lure also attracted female Pro. brevitarsis (10.0 ± 3.4), while the SA attracted only few male beetles (1.0 ± 0.2). The combination SA + floral lure captured similar females (11.0 ± 2.0) and total (14.2 ± 2.2) Pro. brevitarsis as the floral lure alone. Two butterflies, Colias erate poliographus (Motschulsky) and Pieris rapae (Linnaeus), were also attracted to the floral lure. These studies indicate a potential for replacing pesticides by using the Japanese beetle lures for monitoring and control of several insects in China, and that they would be useful in monitoring and eradication of two potential scarab pests, P. quadriguttata and Pro. brevitaris, in the United States and Europe.     

Female sex pheromone components of Helicoverpa gelotopoeon: first heliothine pheromone without (Z)-11-hexadecenal

Helicoverpa gelotopoeon Dyar is a very important pest of economic importance on cotton in Argentina. Analysis of female pheromone gland extracts prepared from 1‐ to 2‐day‐old virgin female moths demonstrated the presence of a 1 : 0.84 blend of hexadecanal (16:Ald) and (Z)‐9‐hexadecenal (Z9‐16:Ald), with trace quantities of tetradecanal in some samples, 2.4% of 16:Ald. The average quantity of Z9‐16:Ald extracted per female was estimated to be 33 ng, with a range of 18.9–46.4 ng per female when collected 2–3 h into the scotophase. In field trials conducted in both cotton and tomato crops in Santiago del Estero, Argentina 1 : 1 blends of 16:Ald and Z9‐16:Ald caught significantly more male H. gelotopoeon than Z9‐16:Ald alone, although there was no significant difference between blends containing between a 0.2 : 1 and 2 : 1 ratio of 16:Ald and Z9‐16:Ald. There was no analytical evidence for the presence of (Z)‐11‐hexadecenal (Z11‐16:Ald) in pheromone gland extracts, although this compound has been identified in all female sex pheromones of Heliothinae to date. In field trials, the addition of Z11‐16:Ald at the 1% level to either a 1 : 1 blend of 16:Ald and Z9‐16:Ald or Z9‐16:Ald alone significantly reduced the catch of male H. gelotopoeon. Sympatric Heliothis virescens were not caught in any of the blends tested for H. gelotopoeon, but were caught in low numbers in traps baited with a 4 : 100 blend of (Z)‐9‐tetradecenal and (Z)‐11‐hexadecenal.     

Electrophysiological and behavioral responses of Helicoverpa assulta (Lepidoptera: Noctuidae) to tobacco volatiles

The Oriental tobacco budworm moth, Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae), is a serious pest on tobacco in China. The flowering stage of the host plant is one of the most attractive stages to H. assulta for feeding and oviposition. Nine electrophysiologically active compounds in tobacco headspace at flower stage were detected by gas chromatography?Celectroantennographic detection (GC?CEAD). These compounds were subsequently identified by gas chromatography-mass spectrometry (GC?CMS) as (E)-??-ocimene, octanal, (Z)-3-hexenyl acetate, (Z)-3-hexen-1-ol, nonanal, (Z)-3-hexenyl-2-methyl butyrate, decanal, linalool, and (E)-??-caryophyllene. The synthetic blend containing nine of the above compounds attracted mated H. assulta females from a distance by upwind oriented flight. Selected subtraction assays showed that the 4-component mixture of (E)-??-ocimene, (Z)-3-hexenyl acetate, nonanal, and (E)-??-caryophyllene elicited equivalent levels of attraction as the 9-component mixture. The removal of any of the four compounds from the 4-component blend resulted in a significant decrease in female upwind flight behavior.     

Aplysinopsin analogs: Synthesis and anti-proliferative activity of substituted (Z)-5-(N-benzylindol-3-ylmethylene)imidazolidine-2,4-diones

A series of substituted (Z)-5-(N-benzylindol-3-ylmethylene)imidazolidine-2,4-dione (3) analogs structurally related to aplysinopsin, and that incorporate a variety of substituents in both the indole and N-benzyl moieties have been synthesized under microwave irradiation and conventional heating methods These analogs were evaluated for their anti-proliferative activity against MCF-7 and MDA-231 breast cancer cell lines, and A549 and H460 lung cancer cell lines. Two analogs, 3f and 3j had IC₅₀ values of 4.4 and 5.2 μM, respectively, compared to 5-fluorouracil (IC₅₀ = 15.2 μM) against MCF-7 cells.     

Sex pheromone components of the rice leaffolder,Cnaphalocrocis medinalis (Lepidoptera: Crambidae), in Indonesia

Field tests of three synthetic sex pheromone blends (Japanese blend: Z11–18:Ald (55 μg), Z13–18:Ald (500 μg), Z11–18:OH (120 μg) and Z13–18:OH (180 μg), Indian blend: Z11–16:Ac (50 μg) and Z13–18:Ac (500 μg) and Philippine blend: Z11–16:Ac (500 μg) and Z13–18:Ac (10 μg) based on geographic variations in sex pheromones) of the rice leaffolder moth, Cnaphalocrocis medinalis Guenée (Lepidoptera: Crambidae), were conducted at Yogyakarta (Java), and at Sempidi and Penatih (Bali), Indonesia. Only the Japanese blend attracted significant numbers of male C. medinalis, while neither the Indian nor the Philippine blend showed any attractiveness to the males. In the GC–MS analysis of a crude extract from pheromone glands of female C. medinalis collected at Sanur, Bali. Indonesia, Z11–18:Ald, Z13–18:Ald, Z11–18:OH and Z13–18:OH were detected at a ratio of 10:100:26:37, and the total amount was approximately 0.8 ng/female. Neither Z11–16:Ac nor Z13–18:Ac were detected. These results suggest that C. medinalis that respond to the Japanese blend are widely distributed from Eastern Asia through Southeast Asia.     

Sex pheromone of the iris gelechiid moth Monochroa divisella

The iris gelechiid moth, Monochroa divisella (Douglas) (Lepidoptera: Gelechiidae), is a serious pest in iris horticulture. The overuse of pesticides for conventional control has a great risk of water pollution because irises are often planted in damp areas. To minimize pesticide applications, it is essential to monitor moth emergence by using pheromone traps. The female pheromone of M. divisella was analyzed by means of gas chromatography‐electroantennographic detection (GC‐EAD) and GC‐mass spectrometry. Two male EAD‐active compounds were detected and identified as (Z)‐3‐dodecenyl acetate (Z3‐12:Ac) and (Z)‐5‐tetradecenyl acetate (Z5‐14:Ac), the amounts of which were ca. 40 and 6 ng per female (100:15), respectively. Synthetic Z3‐12:Ac alone attracted only a few males in field trap experiments, but the attractiveness was significantly enhanced when 15% (wt/wt) Z5‐14:Ac was added; traps baited with their binary mixtures captured 21.3‐106.4 males/trap/day, as compared with 2.3 males/trap/day attracted by a crude extract of 10 virgin females. We conclude that Z3‐12:Ac and Z5‐14:Ac are M. divisella pheromone components, which can be offered as an attractant in monitoring traps. Although dodecenyl acetates are a major class of lepidopteran pheromone components, those with the double bond at the 3 position are rare and appear to be unique to gelechiids.     

Design,synthesis and biological evaluation of (E)-2-(2-arylhydrazinyl)quinoxalines,a promising and potent new class of anticancer agents

A series of forty-seven quinoxaline derivatives, 2-(XYZC₆H₂CHN–NH)-quinoxalines, 1, have been synthesized and evaluated for their activity against four cancer cell lines: potent cytotoxicities were found (IC₅₀ ranging from 0.316 to 15.749 μM). The structure–activity relationship (SAR) analysis indicated that the number, the positions and the type of substituents attached to the aromatic ring are critical for biological activity. The activities do not depend on the electronic effects of the substituents nor on the lypophilicities of the molecules. A common feature of active compounds is an ortho-hydroxy group in the phenyl ring. A potential role of these ortho-hydroxy derivatives is as N,N,O-tridentate ligands complexing with a vital metal, such as iron, and thereby preventing proliferation of cells. The most active compound was (1: X,Y = 2,3-(OH)₂, Z = H), which displayed a potent cytotoxicity comparable to that of the reference drug doxorubicin.     

(Z)-9-tetradecenal: a potent inhibitor of pheromone-mediated communication in the oriental tobacco budworm moth,Helicoverpa assulta

The behavioural significance of (Z)-9-tetradecenal to male H. assulta was tested by comparing the number of moths attracted to lures containing a standard synthetic female sex pheromone with lures in which (Z)-9-tetradecenal was also added. The standard pheromone mixture used contained 1000 g (Z)-9-hexadecenal, 50 g (Z)-11-hexadecenal, 300 g (Z)-9-hexadecenyl acetate and 15 g (Z)-11-hexadecenyl acetate impregnated on rubber septa. Addition of (Z)-9-tetradecenal to the standard pheromone was shown to significantly reduce the caught of male H. assulta when added in amounts greater than 10 g or 1% of the major pheromone component in both field and net-house experiments. The reduction in catch was found to be dependent on the quantity of (Z)-9-tetradecenal added to the standard pheromone. The implications of these results on conspecific and inter-specific pheromone-mediated communication in H. assulta and related sympatric heliothine species is discussed.Abbreviations Z9-16:AL (Z)-9-hexadecenal - Z11-16:AL (Z)-11-hexadecenal - Z9-16:AC (Z)-9-hexadecenyl acetate - Z11-16:AC (Z)-11-hexadecenyl acetate - Z9-14:AL (Z)-9-tetradecenal - Z9-16:OH (Z)-9-hexadecen-1-ol - Z11-16:OH (Z)-11-hexadecen-1-ol - RH relative humidity     

Sex pheromone composition of the variegated cutworm,Peridroma saucia (Lepidoptera: Noctuidae), in Korea

This study was conducted to investigate the sex pheromone composition of the variegated cutworm (Peridroma saucia Hübner) in Korea. The sex pheromone components of P. saucia were identified as (Z)-9-tetradecenyl acetate (Z9-14:Ac) and (Z)-11-hexadecenyl acetate (Z11-16:Ac) through GC-EAD and GC–MS analysis. EAG tests of the male antennae revealed that the Z9-14:AC exerted significantly larger responses than other compounds. The female moths primarily called and copulated between 6 h and 7 h after the lights off, and the ratio of two pheromone components, Z9-14:Ac and Z11-16:Ac, in the sex pheromone gland during this period was 1:2.1 to 1:2.4. In the field trapping studies, a large number of male moths were caught in the traps baited with the mixtures of Z9-14:Ac and Z11-16:Ac at the ratios ranging from 2.3:1 to 1:4, with the highest trap catches at 1:1 to 1:2.3 ratios of the two components. The seasonal flight activities of P. saucia monitored by using pheromone lures revealed complicated patterns in Korea. Specifically, the first flight period was spread over a long period and irregular, while the second flight period differed among the localities examined.     

Optimized synthesis of (Z)-3-hexen-1-yl caproate using germinated rapeseed lipase in organic solvent

(Z)-3-hexen-1-yl esters are important green top-note components of food flavors and fragrances. Effects of various process conditions on (Z)-3-hexen-1-yl caproate synthesis employing germinated rapeseed lipase acetone powder in organic solvent were investigated. Rapeseed lipase catalyzed ester formation more efficiently with non-polar compared to polar solvents despite high enzyme stability in both types of solvents. Maximum ester yield (90%) was obtained when 0.125 M (Z)-3-hexen-1-ol and caproic acid were reacted at 25 °C for 48 h in the presence of 50 g/L enzyme in heptane. Enzyme showed little sensitivity towards a_w with optimum yield at 0.45, while added water did not affect ester yield. Esterification reduced by increasing molecular sieves (>0.0125%, w/v). The highest yields of caproic acid were obtained with isoamyl alcohol (93%) followed by butanol and (Z)-3-hexen-1-o1 (88%) respectively reflecting the enzyme specificity for straight and branched chain alcohols. Secondary alcohols showed low reactivity, while tertiary alcohol had either very low reactivity or not esterified at all. A good relationship has been found between ester synthesis and the solvent polarity (log P value); while no correlation for the effect of solvents on residual enzyme activity was observed. It may be concluded that germinated rapeseed lipase is a promising biocatalyst for the synthesis of valuable green flavor note compound. The enzyme also showed a wide range of temperature stability (5–50 °C).     

Responses of Mamestra suasa male moths to synthetic pheromone compounds in a wind tunnel

The upwind flight and landing responses of male Mamestra suasa (Den. & Schiff.) (Lepidoptera; Noctuidae) to various synthetic chemicals were studied in a wind tunnel. A mixture of (Z)-11-hexadecenyl acetate (Z11-16: Ac) and (Z)-11-hexadecenal (Z11-16: Ald) elicited upwind flight responses past the midpoint of the wind tunnel, and both components were necessary for landing of the males to occur at the pheromone source point. The best response to the mixtures tested was to a ratio 100:1 (ng) of Z11-16: Ac and Z11-16: Ald (blend B).The addition of (Z)-9-tetradecenyl acetate (Z9-14: Ac) (10 ng) to blend B resulted in a significant decrease of upwind flight and landing responses. The inhibitory effect of this chemical when it is mixed with blend B, and the presence of a specific receptor for this compound in sensilla trichodea of male M. suasa, suggest that Z9-14: Ac is involved in the chemical communication between M. suasa and other sympatric species. The addition of (Z)-11-hexadecenol (Z11-16: OH) (1 or 10 ng) to blend B had no effect on male upwind flight and landing responses. This compound does not seem to be involved in the chemical communication of this species.

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Résumé L'observation et la comptabilisation des vols orientés et des atterrissages des mâles de Mamestra suasa (Den. & Schiff.) (Lepidoptera; Noctuidae) sur une source de phéromone de synthèse ont mis en évidence un mélange attractif appelé mélange B et constitué par 100 ng de Z11-16: Ac et 1 ng de Z11-16: Ald. L'attraction et l'atterrissage sont sous la dépendance du mélange de ces 2 composés. Les variations de leurs proportions relatives affectent les différentes phases du comportement de vol des mâles.L'addition de 10 ng d'acétoxy-1 tetradécène-9 Z (Z9-14: Ac) diminue significativement les proportions de vols orientés et d'atterrissages par rapport aux réponses obtenues avec le mélange B seul. L'effet inhibiteur de cette molécule sur l'attractivité du mélange B et la présence chez M. suasa d'un récepteur spécialisé dans la perception de ce composé suggèrent que le Z9-14: Ac est impliqué dans la communication chimique entre M. suasa et d'autres espèces sympatriques. L'addition d'hexadécènol-11 Z (Z11-16: OH) au mélange B à la dose de 1 ou 10 ng ne modifie pas les réponses des mâles. Ce composé ne semble pas impliqué dans la communication chimique chez M. suasa.

     

Source and cyclic release pattern of (Z)-7-dodecenyl acetate, the pre-ovulatory pheromone of the female Asian elephant

Female Asian elephants (Elephas maximus) release a pre-ovulatory urinary pheromone, (Z)-7-dodecenyl acetate (Z7--12:Ac), to signal males of their readiness to mate. Z7--12:Ac is quantitatively elevated during the follicular stage of estrus, reaching maximum concentrations just prior to ovulation, as demonstrated by two complementary headspace techniques: (i) evacuated canister capture followed by cryogenic trapping; (ii) solid phase microextraction (SPME), used prior to gas chromatography/ mass spectrometry (GC/MS). These patterns were coincident with observed male behaviors and were consistent with biochemical and binding properties of the active ligand, including optimal binding pH. To release maximum amounts of Z7--12:Ac for quantitation, serum and urine samples from three mature female Asian elephants in their luteal and follicular stages of several estrous cycles were subjected to heat and pH changes and were then treated with protease prior to SPME-GC/MS analyses. When the post-luteal serum progesterone concentrations declined to baseline levels, Z7--12:Ac became detectable in the female urine. Throughout the follicular stage pheromone concentrations increased linearly with no apparent relationship to the two serum luteinizing hormone peaks. Pre-ovulatory urine also contained related compounds, including (Z)-7--12-dodecenol. The relative amount of this alcohol increased relative to acetate during long-term storage, with a proportional reduction in bioactivity. Z7--12:Ac was not detected in mucus samples from the urogenital tract. A potential precursor of Z7--12:Ac was identified in liver homogenates from female elephants in the follicular stage.