Pest phenology and evaluation of traps and pheromone lures for monitoring flight activity of obliquebanded leafroller (Lepidoptera: Tortricidae) in Minnesota apple orchards

The efficacy of two trap designs (Pherocon 1C "wing" trap versus Pherocon VI "delta" trap) and two pheromone blends for monitoring obliquebanded leafroller, Choristoneura rosaceana (Harris), was evaluated in Minnesota apple orchards during the 2001 and 2002 field seasons. Two distinct flight periods of C. rosaceana were recorded yearly in Minnesota. Overwintered C. rosaceana larvae resumed activity in the spring at approximately 60 degree-days (DD) base 10 degrees C, whereas adult emergence began approximately 275 DD base 10 degrees C. To determine the optimal pheromone blend for monitoring C. rosaceana in Minnesota, traps were baited with either a three-component pheromone blend (Z11-14:Ac, E11-14:Ac, and Z11-14:OH) produced by females in eastern North America, or a four-component blend (Z11-14:Ac, E11-14:Ac, Z11-14:OH, and Z11-14:Al) commonly produced by females in western North America. Of the four pheromone-baited traps evaluated, delta traps baited with the four-component western pheromone lure captured the highest number of C. rosaceana males, followed by wing traps baited with western lure. Male C. rosaceana were less attracted to traps containing the three-component eastern lure, and both lure types seemed to be considerably selective against sympatric redbanded leafroller, Argyrotaenia velutinana (Walker). These results suggest that the pheromonal response of the predominant endemic population of C. rosaceana in Minnesota is similar to the response of the pest in many parts of western North America. The delta trap baited with western pheromone lure of C. rosaceana is recommended for monitoring the pest in Minnesota, and the results are discussed in relation to the development of effective management strategies against this important pest of apple.     

Sex pheromone analysis and effective attraction of males of the cabbage webworm,Hellula undalis,inhabiting the Mekong Delta of Vietnam

Hellula undalis is a harmful insect pest of green mustard in the Mekong Delta of Vietnam. In order to establish a tool for a sustainable pest control program, the sex pheromone of H. undalis inhabiting the Mekong Delta was examined. GC-EAD and GC–MS analyses of pheromone gland extracts from the virgin females elucidated three new components, (Z)-11-tetradecenyl acetate (Z11-14:OAc), (Z)-11-hexadecenal (Z11-16:Ald), and (11E,13E)-11,13-hexadecadien-1-ol, in addition to the known pheromone component (11E,13E)-11,13-hexadecadienal (E11,E13-16:Ald). Double bond positions of the two monoenyl components were determined by GC–MS analysis of the pheromone extract treated with dimethyl disulfide. On the other hand, GC–MS analysis of the female body extract detected the unsaturated hydrocarbon (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H). Field examinations of their synthetic compounds indicated the significant role of E11,E13-16:Ald as a major component and a clear synergistic effect of the two monoenyl compounds as a minor component. Although the 3:3:7 mixture of Z11-14:OAc, E11-16:Ald, and E11,E13-16:Ald captured the largest number of males among the tested mixtures, the activity was still quite a bit lower than that of virgin females. However, the 3:3:7:1 mixture, which was prepared by adding a small amount of Z3,Z6,Z9-23:H to the 3:3:7 ternary lure, succeeded in attracting males more powerfully than the females did. This strong synergistic effect was not observed when the triene was added to unmixed E11,E13-16:Ald, indicating important roles of not only the triene but also the two monoenyl compounds as natural pheromone components.     

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.     

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.     

榆木蠹蛾雄蛾对性信息素不同组分及其不同比例和剂量混合物的风洞行为反应

【目的】本研究旨在深入了解榆木蠹蛾Holcocerus vicarius(Walker)信息素通讯系统。【方法】在风洞中观察了榆木蠹蛾雄蛾对合成性信息素不同组分及其不同比例及剂量混合物的行为反应。【结果】单组分试验结果表明,仅有Z7-14:Ac能够引起少量雄蛾完成从兴奋到接触诱芯并出现预交尾的全部行为反应,其余4个单组分(E3-14:Ac,Z3E5-14:Ac,E3-14:OH和Z3-14:OH)只能引起雄蛾兴奋,均不能引起雄蛾向性信息素源定向飞行。二元混合物(Z7-14:Ac+E3-14:Ac)明显增加雄蛾完整的性行为反应比例,三元混合物(Z7-14:Ac+E3-14:Ac+Z3E5-14:Ac)比例为10∶4∶4,剂量为1 300μg时有71.7%雄蛾发生预交尾,剂量为1 000μg时有70.3%雄蛾发生预交尾,两者差异不显著(P0.05)。【结论】榆木蠹蛾风洞行为实验为进一步研究其性信息素相关生物学特性及应用性信息素对榆木蠹蛾进行综合防治奠定了基础。     

Optimization of pheromone lure and trap design for monitoring the fir coneworm, Dioryctria abietivorella

The major components of the sex pheromone of Dioryctria abietivorella (Groté) (Lepidoptera: Pyralidae) were recently identified as (9Z,11E)‐tetradecadien‐1‐yl acetate (9Z,11E‐14:Ac) and a polyunsaturated, long‐chain hydrocarbon (3Z,6Z,9Z,12Z,15Z)‐pentacosapentaene (C25 pentaene). The optimal ratio of these components and the role of potential minor components were not fully determined in the initial short report on the pheromone's identification. We tested different ratios of the two major components loaded into grey halobutyl rubber septum dispensers, placed in sticky traps deployed in conifer breeding arboreta. The optimal ratio of the two components was 200 µg 9Z,11E‐14:Ac to 2000 µg C25 pentaene. (Z)‐9‐Tetradecen‐1‐yl acetate, which had been identified previously in female pheromone gland extracts, and five other potential minor pheromone components, were tested individually as additions to the optimized two‐component lure blend. None of the ternary blends were more attractive than the optimized two‐component blend, at the ratios tested. Two lure adjuvants, a UV stabilizer (Sumisorb 300) and the antioxidant butylated hydroxytoluene, added individually or together, did not affect the attractiveness of the optimized lure blend. The Pherotech diamond sticky trap baited with the optimized lure blend was the most effective trap design among eight types of sticky trap and a bucket style trap that were tested. Traps baited with synthetic lures were as attractive as traps baited with virgin female moths. The optimized two‐component lure blend in the Pherotech diamond trap is recommended for monitoring fir coneworm infestations. The availability of an effective synthetic pheromone opens the possibility for control tactics using mating disruption or attract‐and‐kill techniques.     

Identification of a four-component sex pheromone blend in Bonagota cranaodes (Lepidoptera: Tortricidae)

Analysis of sex pheromone glands of the apple leafroller Bonagota cranaodes Meyrick by gas chromatography coupled with mass spectrometry or electroantennographic detection showed the presence of 14 structurally related acetates and alcohols of the chain length 10-18, including the main pheromone component (E,Z)-3,5-dodecadienyl acetate (E3,Z5-12Ac). Male antennae responded to the main compound, its Z,Z isomer, (E,Z) -3,5-tetradecadienyl acetate (E3,Z5-14Ac), and the monoenes (Z)-5-dodecenyl acetate (Z5-12Ac) and (Z)-9-hexadecenyl acetate (Z9-16Ac). Traps baited with a four-component blend of E3,Z5-12Ac, Z5-12Ac, E3,Z5-14Ac, and Z9-16Ac in a 100:5:5:100 ratio were significantly more attractive than the main compound alone. This improved trap lure is more suitable for monitoring population densities of B. cranaodes, and for detection of the onset of the seasonal flight period. A more complete pheromone blend is of importance also with respect to current attempts to develop mating disruption for control of this major pest of apple in Brazil.     

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.     

Identification of the sex pheromone of Isoceras sibirica Alpheraky (Lepidoptera, Cossidae)

We discovered that extracts of the female sex pheromone gland of the carpenterworm moth Isoceras sibirica Alpheraky, a pest of Asparagus officinalis Linn., contained (Z)-7-tetradecen-1-ol (Z7-14:OH), (Z)-9-tetradecen-1-ol (Z9-14:OH), (Z)-7-tetradecenyl acetate (Z7-14:Ac), (Z)-9-tetradecenyl acetate (Z9-14:Ac), and (Z)-9-hexadecadecenyl acetate (Z9-16:Ac). The average levels of the chemicals in a single sex pheromone gland of a calling moth were (0.71 +/- 0.24) ng, (1.42 +/- 0.44) ng, (4.36 +/- 0.32) ng, (8.71 +/- 0.26) ng, and (0.82 +/- 0.38) ng, respectively. The electroantennography (EAG) analysis of these chemicals and their analogues demonstrated that Z9-14:Ac triggered significantly the male EAG response. Traps with rubber septa lure impregnated with Z9-14:Ac (500 microg/septum), Z7-14:Ac (250 microg/septum), and Z9-16:Ac (50 microg/septum) were more effective in catching male moths than traps with other baits or virgin females. Addition of Z7-14:OH and Z9-14:OH to rubber septa did not enhance the efficiency of the trap.     

植物气味化合物与斜纹夜蛾性信息素的协同作用

为提高现有性信息素对雄蛾的引诱活性, 本研究通过大量的田间试验探索植物气味化合物与斜纹夜蛾Spodoptera litura性信息素（顺9, 反11-十四碳二烯乙酸酯∶顺9, 反12-十四碳二烯乙酸酯=10∶1）的协同作用机制。从斜纹夜蛾寄主植物和花的气味化合物中, 选择9种有代表性的化合物, 并以一定剂量分别加入到斜纹夜蛾性信息素诱芯中, 在田间测试对雄蛾的引诱活性。结果表明: 在测试的9种植源性化合物中, 发现一定剂量(每个诱芯加入0.4 mg)的苯乙醛(PAA), 具有显著提高斜纹夜蛾性信息素的引诱作用, 而高剂量的苯乙醛则强烈抑制性信息素的引诱活性; 此外, 其他各种浓度的测试化合物或混合物对性信息素则没有统计上显著的增效作用。不同剂量的苯乙醛单个化合物及各种植物气味化合物组成的混合物对斜纹夜蛾也有微弱的引诱作用。苯乙醛必须要与性信息素的完整组分(以10∶1比例混合的顺9, 反11-十四碳二烯乙酸酯和顺9反, 12-十四碳二烯乙酸酯)混合才能起作用, 缺少顺9, 反12-十四碳二烯乙酸酯则没有引诱活性。本研究证明, 苯乙醛作为理想的性信息素诱芯增效剂, 可应用于建立更理想的斜纹夜蛾性信息素诱杀技术, 对性诱害虫防治和测报具有应用价值。     

田间二化螟雄蛾对不同配比性信息素的嗅觉反应 及性信息素识别相关基因表达水平差异

【目的】本研究旨在从行为和嗅觉分子水平探究二化螟Chilo suppressalis雄蛾对性信息素嗅觉反应的地理种群差异及其机理,以明确该害虫田间种群雄成虫的嗅觉适应性及其特点。【方法】采用7种Z11-16∶Ald, Z9-16∶Ald和Z13-18∶Ald配比不同的三元性信息素诱芯(Z11-16∶Ald和Z9-16∶Ald配比分别为540 μg∶540 μg, 864 μg∶216 μg, 945 μg∶135 μg, 980 μg∶98 μg, 1 003 μg∶77 μg, 1 016 μg∶64 μg和1 045 μg∶35 μg,而Z13-18∶Ald含量保持不变),在中国6省水稻田间诱捕二化螟雄成虫;利用实验室风洞测定864 μg∶216 μg, 980 μg∶98 μg和1 016 μg∶64 μg配比诱芯在田间诱捕的越冬代和第2代二化螟雄蛾分别对这3个配比的性信息素诱芯的行为反应;并采用RT-qPCR方法测定这7种性信息素配比不同的诱芯诱捕的雄蛾触角中二化螟雄蛾12个性信息素识别相关基因的表达水平。【结果】在田间试验中,Z11-16∶Ald和Z9-16∶Ald不同配比的性信息素诱芯对水稻二化螟雄蛾均有引诱作用,但不同配比引诱的二化螟雄蛾占比不同。6省诱芯中Z11-16∶Ald和Z9-16∶Ald的最佳配比不同,并且同一配比性信息素诱芯在不同省份引诱的二化螟雄蛾占比也不同。结果表明,不仅在不同地区诱芯的性信息素最佳配比不同,而且在不同地区不同配比性信息素的诱蛾量占比也不同。实验室风洞试验中,864 μg∶216 μg和1 016 μg∶64 μg配比诱芯田间诱捕雄蛾分别对864 μg∶216 μg和1 016 μg∶64 μg配比诱芯的行为反应均显著强于对其余两种配比诱芯,980 μg∶98 μg配比诱芯田间诱捕雄蛾对1 016 μg∶64 μg, 980 μg∶98 μg和864 μg∶216 μg配比诱芯的行为反应无显著差异。在RT-qPCR测定中,除GOBP1外,其余11个性信息素识别相关基因在Z11-16∶Ald和Z9-16∶Ald不同配比诱芯诱捕雄蛾触角中的表达水平均存在显著差异,其中PBP3, PBP4, PR1, PR2, PR4, PR5和PR6 7个基因的表达水平与性信息素配比之间存在显著的线性相关。【结论】本研究明确了中国二化螟不同地理种群性信息素嗅觉差异,不仅有助于提高该害虫的性诱防控效率,而且也有助于理解其嗅觉地理种群差异的成因。     

枣镰翅小卷蛾雄蛾对性信息素的行为反应

在风洞中观察了枣镰翅小卷蛾Ancylis sativa雄蛾对合成性信息素不同组分(E9-12∶Ac和Z9-12∶Ac)的行为反应。E9-12∶Ac组分能够引起少量雄蛾(8-3%)完成从兴奋到接触诱芯并呈现交配企图的全部行为反应,而雄蛾对Z9-12∶Ac组分无反应。E9-12∶Ac+Z9-12∶Ac混合物中前者占60%～65%效果最好,能使71.7%～76.7%雄蛾到达诱芯并呈现交配企图。E9-12∶Ac与Z9-12∶Ac为6.5∶3.5时,200 ng～2 000 ng的剂量效果最好,有76.7%～81.7%雄蛾到达诱芯。     

Trapping effect of synthetic sex pheromone of Acleris fimbriana (Lepidoptera: Tortricidae) in Chinese northern orchard

The yellow tortrix, Acleris fimbriana Merick (Lepidoptera: Tortricidae), is an economically important insect pest on fruit trees with four generations a year in North China. In order to develop a new and effective method for forecasting and controlling the pest, the sex pheromone was studied. We have identified the female sex pheromone as (E)-11,13-tetradecadienal (E11,13-14:Ald), (E)-11,13-tetradecadienyl acetate (E11,13-14:Ac) and (E)-11-tetradecenyl acetate (E11-14:Ac). Trapping effect of synthetic chemicals E11,13-14:Ald, alone and in combination with E11,13-14:Ac or/and E11-14:Ac to A. fimbriana males was tested in Beijing Xishan Orchard (2001). E11,13-14:Ald on its own was much attractive to A. fimbriana males. Neither E11,13-14:Ac nor E11-14:Ac alone caught any moths. The catches markedly increased by adding E11,13-14:Ac to E11,13-14:Ald. The optimum ratio of E11,13-14:Ald and E11,13-14:Ac was 6:4 to 5:5. This attractiveness was apparently enhanced when 5% to 10% of E11-14:Ac was added. The best field activity was in the lure baited with a 6:4:1 ratio of E11,13-14:Ald, E11,13-14:Ac and E11-14:Ac at a dosage of 1000 microg/septum. The effect of antioxidant, 2,6-di-tert-butyl-4-methylphenol [butylated hydroxyluene (BHT)], to the synthetic pheromone blends on its duration and catching efficacy was also tested. Addition of 5-10% BHT to the synthetic pheromone could prolong the life-span of pheromone chemicals for 6-8 weeks, thereby increased its catching efficacy.     

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.     

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.     

Sulfhydryl-reagent inhibition of olfaction in a moth and effects of exposure to pheromone compounds or a pheromone analogue

The effects on olfaction of N-ethylmaleimide (NEM), a specificreagent of free sulfhydryl groups, were studied in the mothMamestra brassicae. The antennae of male M.brassicae bear twotypes of specialist receptor neurons involved in pheromone communication.One type is tuned to (Z)-11-hexadecenyl acetate (Z11-16:Ac),the main pheromone component; the second type is tuned to (Z)-9-tetradecenylacetate (Z9-14:Ac), an interspecific inhibitor not producedby the females of this species. Vapours of NEM irreversiblyinhibited the electro-antennographic (EAG) responses to Z11-16:Acand Z9-14:Ac. When Zll-16:Ac was applied before and during NEMtreatment, the responses to Z9-14:Ac were preserved and someprotection was observed in the responses to Zll-16:Ac. In return,Z9-14:Ac partially prevented the disappearance of responsesto Zll-16:Ac but not to Z9-14:Ac. A third compound, hexadecylacetate (16:Ac), found in the pheromone gland, but not detectedby the antennal receptors, did not prevent the inhibition causedby NEM.     

A new pheromone race of Acrobasis nuxvorella (Lepidoptera: Pyralidae)

The sex pheromone of the monophagous Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae) was reported as (9E,11Z)-hexadecadienal (9E,11Z-16:Ald) (Biorg. Med. Chem. 4: 331-339, 1996), and it has since been an effective integrated pest management (IPM) tool for monitoring this pest in the United States, but not in Mexico. Field and laboratory studies were conducted to confirm that the species in Mexico was indeed A. nuxvorella and to investigate the pheromone chemistry of the Mexican populations of this species. Initial field trials testing compounds structurally related to the known pheromone component, and blends thereof, indicated that a 100 microg:100 microg blend of (9E,11Z)-hexadecadien-1-yl acetate (9E,11Z-16:Ac):9E,11Z-16:Ald in rubber septa was effective in attracting male moths in Mexico. Coupled gas chromatography-electroantennogram analyses confirmed the presence of these compounds in extracts of pheromone glands of females, and antennae of male moths also responded to the alcohol analog (9E,11Z)-hexadecadien-1-ol (9E,11Z-16:OH). Subsequent field trials of various blends of these three compounds in Mexico showed that 1) both the acetate and aldehyde components were required for optimal attraction of male moths of the Mexican populations, and 2) addition of the alcohol suppressed attraction of males in a dose-dependent manner. Tests with the 1:1 9E,11Z-16:Ac:9E,11Z-16:Ald blend at various sites in the United States showed that this blend attracted some moths, but that moths attracted to 9E,11Z-16:Ald alone were predominant in the population. Furthermore, in preliminary studies the latter seemed not to respond to the blend. These findings indicate that there are two pheromone types of the pecan nut casebearer, and they have major implications for the direct use of these pheromones in pecan IPM.     

(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 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.     

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.