Control of pheromone biosynthesis in mated redbanded leafroller moths

Mating in the redbanded leafroller moth, Argyrotaenia velutinana, causes a permanent decline in pheromone titers. Three hours following the termination of mating, phermone titers were significantly decreased from premating levels, and titers remained low for at least four days after mating. Pheromone titers were similar in females that had been decapitated or mated for twenty-four hours. In the redbanded leafroller moth, two peptides control pheromone production. The pheromone biosynthesis activating neuropeptide is produced in the brain and the pheromonotropic bursa peptide is produced in the corpus bursae. Both peptides stimulated pheromone biosynthesis in mated females and extracts prepared from brains and bursae of mated females contained pheromonotropic activity. However, severing the ventral nerve cord before mating prevented the decline in pheromone titer that occurred in mated females. Hemolymph collected during scotophase from mated females did not have pheromonotropic activity, whereas hemolymph collected during scotophase from virgin females contained activity. These results indicate that mating produces a signal sent by the ventral nerve cord to the brain to stop the release of pheromone biosynthesis activating neuropeptide. © 1993 Wiley-Liss, Inc.     

Sex pheromone titre in the glands of Spodoptera litura females: circadian rhythm and the effects of age and mating

The present study investigates the effects of age and mating status on the circadian variations of gland sex pheromone titre in female Spodoptera litura Fabricius. Similar to other nocturnal moths, S. litura females exhibit circadian variations of gland sex pheromone contents, with higher levels during scotophase and lower levels during photophase. The sex pheromone titre in the glands peaks during the first scotophase after eclosion and sharply declines afterwards. Higher pheromone contents during scotophase may facilitate female reproductive activities, and the negative relationship between pheromone titre and female calling is likely the result of pheromone release during female calling. Interestingly, the present study demonstrates that mated S. litura females have significantly higher sex pheromone titre in their pheromone glands (PGs) than virgin females. This finding contrasts with all previous studies of other insect species, in which mating generally reduces the sex pheromone titre in female PGs. In S. litura, mating and male accessory gland fluids can suppress female calling behaviours and re‐matings. These results suggest that the suppression of female calling behaviours by mating and male accessory gland fluids may significantly reduce the release of sex pheromones and thus result in higher sex pheromone titre in the PGs of mated females.     

Male Accessory Gland Secretions Modulate Female Post-Mating Behavior in the Moth Spodoptera litura

The study of male insects’ accessory gland (MAG) secretions will promote our understanding of reproductive strategies and their evolution, and will facilitate the development of new approaches for pest control. Here, we carried out a series of experiments to determine the functions of MAG secretions on modulating female post-mating behavior in the moth Spodoptera litura. Results showed that females injected with MAG secretions called and mated significantly less than controls in the night after treatment, which were independent of mechanical stimulation during mating and the presence of sperm. However, a successful mating resulted in a longer loss in sexual receptivity (lasting to the second night after mating). This study also demonstrated that MAG secretions not only triggered oviposition but also promoted egg development, which also were not dependent on mechanical stimulation during mating and the presence of sperm. MAG secretions also showed negative effect on female longevity, which may be because MAG secretions stimulate females to allocate more resources to egg development and oviposition, leaving fewer resources for survival. Results of this study also suggest that oviposition behaviors incur energy costs. The hypothesis that virgin females may conduct oosorption to prolong longevity is not supported.     

Female sex pheromone suppression and the fate of sex-peptide-like peptides in mated moths of Helicoverpa armigera

Insect males produce accessory gland (MAG) factors that are transferred in the seminal fluid to females during copulation, and elicit changes in the mated female's behavior and physiology. Our previous studies showed that the injection of synthetic Drosophila melanogaster sex-peptide (DrmSP) into virgin females of the moth Helicoverpa armigera causes a significant inhibition of pheromone production. In this and other moth species, pheromone production, correlated with female receptivity, is under neuroendocrine control due to the circadian release of the neuropeptide PBAN. In this study, we show that PBAN, present in the hemolymph during the scotophase in females, is drastically reduced after mating. We also identify 4 DrmSP-like HPLC peaks (Peaks A, S1, S2, and B) in MAGs, with increasing levels of DrmSP immunoreactivity during the scotophase, when compared to their levels observed during the photophase. In H. armigera MAGs, a significant reduction in the pheromonostatic peak (Peak B) was already evident after 15 min of copulation, and depletion of an additional peak (Peak S2) was evident after complete mating. Peak A is also detected in female brains, increasing significantly 1 h after mating, at which time inhibition of pheromone biosynthesis also occurs. However, changes corresponding to the other MAG peaks were not detected in mated female tissues.     

Pheromone puffs suppress mating by Plodia interpunctella and Sitotroga cerealella in an infested corn store

The efficacy of pheromone mating disruption was investigated in a 7×6×3 m corn storage room harboring a high population density of Indian meal moth, Plodia interpunctella (Hübner) and Angoumois grain moth, Sitotroga cerealella (Olivier). Pheromones were released from a controlled release dispenser, the metered semiochemical timed release system (MSTRS^TM) at emission rates of 0.6 g min^–1 (Z9,E12:14:Ac for Indian meal moth) and 0.2 g min^–1 (Z7,E11-16:Ac for Angouimois grain moth). Mating disruption efficacy was evaluated using three parameters: male capture in pheromone traps, visual examination of mating behavior, and the incidence and frequency of mating as measured by spermatophores. In three trials, comparisons were made between data collected before pheromone treatment and during treatment. Disruption of pheromone source location by males averaged 70% and 40% for P. interpunctella and S. cerealella, respectively, in the three trials. In addition, reduced levels of copulation by both species were recorded during pheromone treatment. More importantly, significant reductions were recorded in the incidence and frequency of mating by females of both species collected during the treatment period. While 85% of P. interpunctella females collected before pheromone treatment in three trials had mated at least once, only 50% of the females collected during treatment had mated. The mean number of matings, as measured by spermatophores, ranged between 0.8–1.1 and 0.5–0.7 before and during pheromone treatment, respectively. Similarly, a 20–30% reduction in the proportion of mated S. cerealella females was recorded during pheromone treatment. In the three trials, mean number of spermatophores per S. cerealella female averaged 1.0 and 0.7 during the pretreatment and treatment periods, respectively. Additional tests conducted in small boxes also recorded significant mating disruption of both species.     

Calling behavior of the female german cockroach,Blattella germanica (Dictyoptera: Blattellidae)

Virgin German cockroach females, Blattella germanica(L.), were observed, for the first time, to exhibit a characteristic calling behavior during which females emit a volatile sex pheromone. Under a photoperiod of 12L12D, the percentage of 7-day-old virgin females that exhibited this behavior peaked before the end of the scotophase in a similar pattern to the diel periodicity of mating. A clear relationship was evident between calling and stages of sexual receptivity during successive gonotrophic cycles. Females initiated calling 5–6 days after the imaginal molt, when their basal oocytes were 1.6 mm long. If not mated, females continued to exhibit bouts of calling during the next 3–4 days until 24 h before ovulation. Calling was completely suppressed by mating as well as the presence of an egg case in the genital atrium in both virgin and mated gravid females. We suggest that calling and the emission of a volatile sex pheromone serve to attract males from a distance as well as to potentiate responses to contact sex pheromone in aggregations.     

Mating Effect on Sex Pheromone Production of the Oriental tobacco budworm,Helicoverpa assulta

This study was undertaken to clarify the suppression phenomenon of sex pheromone production after mating and its relationship to the physiological mechanism in adult females of Helicoverpa assulta, and determine the mating factor from males causing depletion of sex pheromonc production. Sex pheromone production of H. assulta females was mostly terminated in 3 hours after mating. Mated females maintained with a low titer of sex pheromone until 3 days when it started to increase again, which showed a characteristic of species mating more than once. The mated female again produced pheromone upon injection of pheromone biosynthesis activating neuropeptide (PBAN) or extracts of brain-suboesophageal ganglion complexes (Br-Sg) of mated female, which were shown similar pheromonotropic activities as compared with virgin females. These results indicated that the mating did not inhibit the receptivity of pheromone gland itself and PBAN biosynthesis in suboesophageal ganglion of the mated females. And it seems to support that the depletion of sex pheromone production is responsible for blocking of PBAN release from head. To investigate the mating factor from adult males, when extracts of reproductive organs of male were injected into hemocoel of virgin females evoking depletion of sex pheromone production as shown in mated female. The results suggest that a chemical substance(s) from the male reproductive organs could be responsible for the loss of sex pheromone biosynthesis in H. assulta.     

Regulation of pheromone inhibition in mated females of Choristoneura fumiferana and C. rosaceana

In the spruce budworm, Choristoneura fumiferana, and the obliquebanded leafroller, C. rosaceana, mating significantly depressed pheromone production after 24 h. On subsequent days, the pheromone titre increased slightly in C. fumiferana, but not in C. rosaceana. No pheromonostatic activity was associated with male accessory sex gland (ASG) extracts, 20-hydroxy-ecdysone or hemolymph taken from mated females. However, pheromone production in mated females was not suppressed when the ventral nerve cord (VNC) was transected prior to mating, indicating that an intact VNC is required to permanently switch off pheromone production after mating. As suggested for other moth species, the presence of sperm in the spermatheca probably triggers the release of a signal, via the VNC, to inhibit pheromone production. The fact that in both species the brain-suboesophageal ganglion (Br-SEG) of mated females contains pheromonotropic activity and that their pheromone glands may be stimulated by the synthetic pheromone-biosynthesis-activating-neuropeptide (PBAN) or a brain extract supports the hypothesis that the neural signal prevents the release of PBAN into the hemolymph rather than inhibiting its biosynthesis. Therefore, we speculate that following the depletion of sperm in the spermatheca, the neural signal declines and is less effective in preventing the release of PBAN, thereby stimulating the resumption of pheromone production, as seen in mated C. fumiferana females. In a previous study, mating was shown to induce a significant rise in the juvenile hormone (JH) titre of both Choristoneura female moths, suggesting that post-mating pheromone inhibition may be under hormonal regulation. However, following topical applications or injections of the juvenile hormone analogue (JHA) and JH II into virgins, the pheromone only declined significantly 48 h after treatment in C. rosaceana. This suggests that the significant rise in the hemolymph JH titre after mating in C. rosaceana females plays a role in keeping the pheromone titre consistently low throughout their reproductive life. These findings will be discussed in relation to the different life histories of the two Choristoneura species.     

Causes and correlates of loss and recovery of sexual receptivity inLucilia cuprina females after their first mating

After an initial mating, females of the Australian sheep blowfly, Lucilia cuprina(Diptera: Calliphoridae), rejected mating attempts by males for several days. Almost all (>98%) females were unreceptive 24 h after mating. When tested 9 days after mating receptivity had returned in 24% of females denied the opportunity to oviposit and 45% of females given repeated opportunities to oviposit on liver. Those mated females that regained receptivity mated as readily as virgins. Gravid first-, second-, or third-cycle females that did not oviposit when presented with liver had a higher receptivity than those that laid. These non-layers laid after remating. Injection of 1 male equivalent of an extract of male accessory reproductive glands into virgin females switched off their receptivity within 5 h for at least 8 days. An extract of testis reduced receptivity 5 h after injection but had no detectable effect 3 days after injection. Both extracts increased the tendency of virgin females to oviposit. There was no difference in the sperm stores of females that refused to lay a second egg mass and comprised a high percentage of receptive females and those given no opportunity to lay this egg mass.     

Identification of Differentially Expressed Genes in the Pheromone Glands of Mated and Virgin Bombyx mori by Digital Gene Expression Profiling

Background

Mating decreases female receptivity and terminates sex pheromone production in moths. Although significant progress has been made in elucidating the mating-regulated inactivation of pheromone biosynthesis-activating neuropeptide (PBAN) secretion, little is known about the mating induced gene expression profiles in pheromone glands (PGs). In this study, the associated genes involved in Bombyx mori mating were identified through digital gene expression (DGE) profiling and subsequent RNA interference (RNAi) to elucidate the molecular mechanisms underlying the mating-regulated gene expression in PGs.

Results

Eight DGE libraries were constructed from the PGs of mated and virgin females: 1 h mating (M1)/virgin (V1) PGs, 3 h mating (M3)/virgin (V3) PGs, 24 h mating (M24)/virgin (V24) PGs and 48 h mating (M48)/virgin (V48) PGs (M48 and V48). These libraries were used to investigate the gene expression profiles affected by mating. DGE profiling revealed a series of genes showing differential expression in each set of mated and virgin female samples, including immune-associated genes, sex pheromone synthesis-associated genes, juvenile hormone (JH) signal-associated genes, etc. Most interestingly, JH signal was found to be activated by mating. Application of the JH mimics, methoprene to the newly-emerged virgin females leaded to the significant reduction of sex pheromone production. RNAi-mediated knockdown of putative JH receptor gene, Methoprene tolerant 1 (Met1), in female pupa resulted in a significant decrease in sex pheromone production in mature females, suggesting the importance of JH in sex pheromone synthesis.

Conclusion

A series of differentially expressed genes in PGs in response to mating was identified. This study improves our understanding of the role of JH signaling on the mating-elicited termination of sex pheromone production.     

Termination of sex pheromone production in mated females of the silkworm moth

A mating duration of more than 6 h was necessary to permanently terminate the production of the sex pheromone (bombykol) in the silkworm moth, Bombyx mori L. (Lepidoptera: Bombycidae), although the female formed a bursa copulatrix including a spermatophore and laid fertilized eggs even after mating for only 0.5 h. The 6-h mated female again produced bombykol if given an injection of synthetic pheromonotropic neuropeptide (PBAN), which is known to activate pheromone biosynthesis in a virgin female. Extracts of brain-suboesophageal ganglion (SG) complexes, which were removed from 6- and 24-h mated females, showed strong pheromonotropic activities. These results indicated that the pheromone gland of the mated female maintained its ability to biosynthesize bombykol; however, it could not produce pheromone due to a suppression of PBAN secretion from the SG. Furthermore, bombykol titers did not decrease after mating in females with a transected ventral nerve cord, even after the injection of a spermatophore extract, suggesting that the suppression of PBAN secretion was mediated by a neural signal and not by a substance in the spermatophore. The mated females accumulated (10E, 12Z)-10,12-hexadecadienoic acid, a precursor of bombykol biosynthesis, in their pheromone glands as did decapitated females. © 1996 Wiley-Liss, Inc.     

Mated Redback Spider Females Re-Advertise Receptivity Months after Mating

In many species, selection acts on males to recognize female reproductive status at a distance using pheromones. Unmated females may actively seek to attract males; however, mated females may become cryptic to avoid attracting additional males if multiple matings are costly. Although females of many species cease pheromone production after mating, it is often unclear whether this is a strategic part of a female reproductive strategy, or whether this is because of chemical manipulation by males. If variation in pheromone production is part of the female’s strategy, then we predicted mated females should eventually re‐advertise receptivity if the benefits of multiple mating increase with time since copulation (e.g. because of sperm depletion). Here, we tested this prediction in Australian redback spiders (Latrodectus hasselti). First, we replicated earlier results by showing that virgin males discriminate female maturity and mating status based exclusively on web‐borne chemicals. Our results show this difference must arise from a change in chemical deposition in the web as we controlled for web volume differences between mated and virgin females. Male activity on extracts from webs of virgin females exceeded activity on a solvent control and on extracts of webs of just‐mated females—confirming that female redbacks cease pheromone production immediately after mating. Second, we tested a new prediction that mated females might re‐advertise receptivity near the end of their normal breeding season to replenish diminished sperm stores prior to overwintering. Consistent with the prediction of strategic advertisement, we show that male activity on extracts from females’ webs increased significantly 3 mo after the female first mated (typical length of the breeding season). Thus, these females had begun to add pheromone to their web again. At this time, 26% of these females re‐mated with a second male. If females re‐advertise receptivity to ensure adequate sperm stores, then we predicted a positive relationship between female reproductive output during the 3‐mo interval after copulation and the subsequent intensity of male response to web extracts. However, differences in male activity time were not related to the total number of spiderlings or the number of egg sacs a female had produced during the 3‐mo interval after the first copulation. This result could arise if male chemical manipulation of female receptivity decreases with time after copulation, or if the testing interval used in our study was too long to reveal variation in sperm depletion in females. Thus, although our results are consistent with the idea that females strategically alter pheromonal advertisement, we cannot distinguish this from the hypothesis that female receptivity arises from chemical manipulation by males.     

Male age and strain affect ejaculate quality in the Mexican fruit fly

Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. Furthermore, in mass‐reared insects used for the Sterile Insect Technique, there are often behavioral differences between mass‐reared and wild males, while differences in the ejaculate have been less studied. The ejaculate in insects is composed mainly of sperm and accessory gland proteins. Here, we studied how male age and strain affected (i) protein quantity of testes and accessory glands, (ii) the biological activity of accessory gland products injected into females, (iii) sperm viability, and (iv) sperm quantity stored by females in wild and mass‐reared Anastrepha ludens (Diptera: Tephritidae). We found lower protein content in testes of old wild males and lower sperm viability in females mated with old wild males. Females stored more sperm when mated to young wild males than with young mass‐reared males. Accessory gland injections of old or young males did not inhibit female remating. Knowledge of how male age affects different ejaculate components will aid our understanding on investment of the ejaculate and possible postcopulatory consequences on female behavior.     

Male reproductive investment and queen mating-frequency in fungus-growing ants

Sperm number and male accessory gland compounds are often importantdeterminants of male mating success but have been little studiedin social insects. This is because mating in social insectsis often difficult to manipulate experimentally, and first evidencefor an explicit influence of accessory gland secretions on malemating success in social insects was obtained only recently.Here we perform a comparative analysis of male sexual organsacross 11 species of attine fungus-growing ants, representingboth genera with single- and multiple-queen mating. We foundthat the general morphology of the male sexual organs was verysimilar across all species, but the relative sizes of the accessoryglands and the sperm-containing accessory testes vary significantlyacross species. Small testes and large accessory glands characterizespecies with singly mated queens, whereas the opposite is foundin species with multiply mated queens. However, in the socialparasite Acromyrmex insinuator, in which queens have secondarilyreverted to single mating, males have accessory gland characteristicsreminiscent of the lower attine ants, but without having significantlyreduced their investment in sperm production. We hypothesizethat the main function of accessory gland compounds in attineants is to monopolize male paternity in similar ways as knownfrom other social insects. This would imply that the evolutionof polyandry in the terminal clade of the fungus-growing ants(the leafcutter ants) has resulted in selection for decreasedinvestment by males in accessory gland secretions and increasedinvestment in sperm number, in response to sperm competitionfor sperm storage.     

Correlation between glycerolipids and pheromone aldehydes in the sex pheromone gland of female tobacco hornworm moths,Manduca sexta (L.)

Analysis by TLC and HPLC revealed that the triacylglycerols comprise the most abundant lipid class in the sex pheromone glands of Manduca sexta females. Also, conjugated olefinic acyl analogs of the major pheromone aldehydes occur principally in the triacylglycerols. The amount of triacylglycerols with conjugated diene acyl moieties significantly decreased when the period of pheromone production was extended by 7 h beyond the normal period of pheromone production by 3 injections of pheromone biosynthesis activating neuropeptide (PBAN) at 3 h intervals. This decrease indicates that the triacylglycerols stored in the gland may serve as major sources of pheromone precursors in the biosynthesis of the sex pheromone aldehydes. Furthermore, analysis of pheromone aldehydes and triacylglycerols in the gland from moths treated with PBAN showed that the proportions of the triacylglycerols with conjugated diene moieties were closely correlated with the proportions of aldehydes found in the same gland. This correlation suggests that the proportions of fatty acids bound to certain triacylglycerols regulates the proportions of aldehydes in biosynthesis of the pheromone blend in M. sexta. © 1995 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Pheromone pre-exposure and mating modulate codling moth (Lepidoptera: Tortricidae) response to host plant volatiles

Abstract 1 Two codling moth Cydia pomonella kairomonal attractants, ethyl (E,Z)‐2,4‐decadienoate (pear ester) and (E)‐β‐farnesene, were tested in an insecticide‐sprayed apple orchard and an orchard treated for mating disruption with synthetic pheromone (E,E)‐8,10‐dodecadienol (codlemone). Male captures with pear ester were higher in the pheromone‐treated than in the insecticide‐treated orchard, whereas captures with (E)‐β‐farnesene were not different. Subsequent wind tunnel experiments confirmed that pre‐exposure to sex pheromone codlemone increased the behavioural response of codling moth males to pear ester. This supports the idea that male attraction to the plant volatile pear ester and sex pheromone codlemone is mediated through the same sensory channels. 2 Pear ester is a bisexual codling moth attractant and even captures of female moths were significantly increased in the pheromone‐treated orchard. In the laboratory wind tunnel, pheromone pre‐exposure had no effect on female response to pear ester, but significantly more mated than unmated codling moth females flew upwind towards a pear ester source. Differences in mating status in insecticide‐treated vs. pheromone‐treated orchards may thus account for the differences in female trap captures with pear ester. 3 These findings are important with respect to monitoring of codling moth with pear ester in mating disruption orchards. They also emphasize the importance of host plant volatiles in pheromone‐mediated mating disruption, which has been neglected to date.     

日龄和交配状态对亚洲玉米螟雄蛾内生殖器特征的影响

【目的】揭示日龄和交配对亚洲玉米螟Ostrinia furnacalis雄蛾内生殖器官的影响,以及亚洲玉米螟雄蛾的交配状态和性信息素诱捕之间的关系。【方法】采用行为学和生殖器解剖技术,研究不同日龄和交配状态亚洲玉米螟雄蛾内生殖器特征,并将其与田间性信息素诱捕雄蛾进行比较。【结果】除了精巢、输精管、储精囊、附腺、复射精管和单射精管外,亚洲玉米螟雄蛾内生殖系统还包含1对附腺囊,同时单射精管非角质化区分为5段(PS1-5),PS1又细分为5区(PS1Ⅰ-Ⅴ)。生殖器内含物可分为5级(0-4级),存在充满和未充满生殖器两种状态。1日龄雄蛾内生殖系统不同器官的内含物等级存在差异,但是日龄对雄蛾生殖系统内含物等级无明显影响。交配后0 h亚洲玉米螟雄蛾,除输精管、储精囊和附腺囊外,其余生殖器官内含物等级较未交配雄蛾的均发生显著变化。随着交配后时间的增加,雄蛾生殖器内含物等级逐渐恢复,各器官内含物等级恢复的速度存在差异,交配后60 h所有内含物等级均恢复到未交配状态。但是直到交配后228 h,交配雄蛾PS5内含物仍然表现出断裂等形态特征,和未交配雄蛾存在差异。性信息素引诱雄蛾中有60.9%的生殖系统表现出未交配雄蛾特征。【结论】利用PS5内含物的形态可以鉴别亚洲玉米螟雄蛾的交配状态,性信息素群集诱杀的亚洲玉米螟雄蛾大部分是未交配。本研究结果为亚洲玉米螟雄蛾交配状态的判定和蛾类害虫性信息素测报和防治的有效性提供了一定依据。     

Characterization of oxidase(s) associated with the sex pheromone gland in Manduca sexta (L.) females

An oxidase that converts primary aliphatic alcohols into aldehydes was discovered in the cuticle of the sex pheromone gland and in the papillae anales on the tip of the abdomen of Manduca sexta females. Oxidase activity was not found in the epidermal cells of the pheromone gland where fatty acid precursors of the pheromonal aldehydes are found. This oxidase requires oxygen and water to function and appears to have a rather broad substrate specificity. The activity of the oxidase is reduced by the application of piperonyl butoxide, which also interferes with the PBAN induced production of the natural pheromone aldehydes. However, endogenous alcohols cannot be found in the pheromone gland. Thus, it is not yet clear whether or not the oxidase is involved in the terminal step of biosynthesis of the pheromone aldehydes in M. sexta females. © Wiley-Liss, Inc.

1 This article is a U.S. Government work and, a such, is in the public domain in the United States of America.

     

烟夜蛾雄蛾性附腺因子对雌蛾性信 息素合成的抑制作用

烟夜蛾Helicoverpa assulta处女蛾在交配后1 h,其性信息素滴度即显著降低,72 h内未见恢复。生测结果表明,烟夜蛾性信息素合成抑制因子主要来源于雄蛾性附腺。不同日龄雄蛾性附腺提取物的抑制活性无显著差异。光暗期对其活性具显著影响,暗期中雄蛾的性附腺物质对雌蛾性信息素合成具有较强抑制作用,而光期中雄蛾的性附腺物质不具抑制活性。在暗期的不同时间处理,对处女蛾性信息素合成的抑制作用无显著差异。雄蛾性附腺提取物对雌蛾性信息素合成的抑制作用与注射剂量有明显的相关性,0.2 ME（雄蛾当量）是产生显著抑制作用的最小剂量。对交配雌蛾注射性信息素生物合成激活神经肽（PBAN）提取物后,其性信息素合成又可恢复,这说明雌蛾交配后,性信息素滴度降低的原因是由于缺少了PBAN的调控。