Types Of Pheromones Research Articles

An agent-based model to investigate the roles of attractive and repellent pheromones in ant decision making during foraging

Pharaoh's ants organise their foraging system using three types of trail pheromone. All previous foraging models based on specific ant foraging systems have assumed that only a single attractive pheromone is used. Here we present an agent-based model based on trail choice at a trail bifurcation within the foraging trail network of a Pharaoh's ant colony which includes both attractive (positive) and repellent (negative) trail pheromones. Experiments have previously shown that Pharaoh's ants use both types of pheromone. We investigate how the repellent pheromone affects trail choice and foraging success in our simulated foraging system. We find that both the repellent and attractive pheromones have a role in trail choice, and that the repellent pheromone prevents random fluctuations which could otherwise lead to a positive feedback loop causing the colony to concentrate its foraging on the unrewarding trail. An emergent feature of the model is a high level of variability in the level of repellent pheromone on the unrewarding branch. This is caused by the repellent pheromone exerting negative feedback on its own deposition. We also investigate the dynamic situation where the location of the food is changed after foraging trails are established. We find that the repellent pheromone has a key role in enabling the colony to refocus the foraging effort to the new location. Our results show that having a repellent pheromone is adaptive, as it increases the robustness and flexibility of the colony's overall foraging response.

A New Pheromone Race of <I>Acrobasis nuxvorella</I> (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.

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 μg:100 μg 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.

Assortative Mating between European Corn Borer Pheromone Races: Beyond Assortative Meeting

BackgroundSex pheromone communication systems may be a major force driving moth speciation by causing behavioral reproductive isolation via assortative meeting of conspecific individuals. The ‘E’ and ‘Z’ pheromone races of the European corn borer (ECB) are a textbook example in this respect. ‘Z’ females produce and ‘Z’ males preferentially respond to a ‘Z’ pheromone blend, while the ‘E’ race communicates via an ‘E’ blend. Both races do not freely hybridize in nature and their populations are genetically differentiated. A straightforward explanation would be that their reproductive isolation is a mere consequence of “assortative meeting” resulting from their different pheromones specifically attracting males towards same-race females at long range. However, previous laboratory experiments and those performed here show that even when moths are paired in a small box – i.e., when the meeting between sexual partners is forced – inter-race couples still have a lower mating success than intra-race ones. Hence, either the difference in attractivity of E vs. Z pheromones for males of either race still holds at short distance or the reproductive isolation between E and Z moths may not only be favoured by assortative meeting, but must also result from an additional mechanism ensuring significant assortative mating at close range. Here, we test whether this close-range mechanism is linked to the E/Z female sex pheromone communication system.Methodology/Principal FindingsUsing crosses and backcrosses of E and Z strains, we found no difference in mating success between full-sisters emitting different sex pheromones. Conversely, the mating success of females with identical pheromone types but different coefficients of relatedness to the two parental strains was significantly different, and was higher when their genetic background was closer to that of their male partner's pheromone race.Conclusions/SignificanceWe conclude that the close-range mechanism ensuring assortative mating between the E and Z ECB pheromone races is unrelated to the difference in female sex pheromone. Although the nature of this mechanism remains elusive, our results show that it is expressed in females, acts at close range, segregates independently of the autosome carrying Pher and of both sex chromosomes, and is widely distributed since it occurs both in France and in the USA.

Monitoring Populations of Saddled Prominent (Lepidoptera: Notodontidae) with Pheromone-Baited Traps

Field trials with three types of pheromone traps were performed in eight northern hardwood stands in northern New York state to develop a population-monitoring tool for the saddled prominent, Heterocampa guttivitta (Walker) (Lepidoptera: Notodontidae). Lure specificity and the relationship between pheromone trap catch and subsequent egg density were examined. A study of moth emergence in relation to temperature was designed to determine whether moth activity throughout the flight season can be predicted using a growing degree-day (DD) model. Pherocon 1C wing traps were significantly more effective than the green Unitrap bucket style. Catch was not affected by position when traps were > or =20 m from an opening (road), and lures were specific to saddled prominent. Lure specificity was examined using green Multipher bucket traps, which effectively attracted and held moths. In the first year of the study, number of viable eggs per 10 leaf clusters was significantly correlated (r2 = 0.59) with average moth catch/trap in pheromone-baited Pherocon traps. When differences in stand density (basal area) and relative abundance of sugar maple (percentage of total stems per hectare), the principle host, were accounted for, the multiple regression model also was significant and r2 = 0. 83. Neither model, however, was significant the second year. Using a base temperature of 5.5 degrees C and on-site temperature data, the peak of moth flight occurred at 316 +/- 8 DD and end of flight occurred at 533 +/- 9 DD.

First results on synchrony between seasonal pattern of pheromone trap captures of cotton bollworm, Helicoverpa armigera and appearance of freshly emerged larvae on developing cobs of corn hybrids

Synchrony between development of five corn hybrid varieties of various seasonal growing rates (FAO numbers), seasonal flight pattern of male cotton bollworm, Helicoverpa armigera Hb. (Lepidoptera: Noctuidae), as monitored by pheromone traps, and the subsequent appearance of newly hatched larvae on developing cobs were studied at Mezőhegyes, South-Hungary, in 2003 and 2004. The phenological stages of corn hybrids were evaluated using the Iowa State University Scale (R1–R5), the flight of male moths was monitored by large capacity, funnel type of pheromone traps and the appearance of freshly hatched larvae on developing cobs were counted by visual inspection. The synchrony between the flight peak of male moths and the peak apperance of L1 larvae on cobs was investigated by cross-correlation. In 2003 (average daily temperatures 20.7°C, average daily relative humidity 59.9% for the period of 4–18 July) “DK 391”, “DK 443” and “Maraton” hybrid varieties already reached silking stage (R1) by the time when pheromone traps indicated a peak, at 7 July (peak capture at 3-day intervals 755.5 males/traps). The number of L1 larvae peaked on developing cobs of these varieties also at 7 July (7.0, 4.0 and 3.8 larvae/50 cobs, respectively). The synchrony between the flight peak of male moths and the peak appearance of L1 larvae on cobs was proven (LAG = 0). A rather similar trend was observed in “Vilma” hybrid variety: it reached R1 stage at 7 July, and L1 larvae appeared only a few days later (11 July, 3.8 larvae/50 cobs) (LAG = −1). However, “Maxima” hybrid variety reached R1 stage 1 week later (14 July) than the time of peak captures. Here L1 larvae peaked as late as at 18 July (0.8 larvae/50 cobs), i.e., only after the cob had reached R1 stage (LAG = −3). A reverse order of dates of R1 stage and peak capture was observed in “Maxima” in 2004 (average daily temperatures; 22.5°C, average daily relative humidities 72.6% for the period of 15 July–6 August): it reached R1 stage at 19 July, while peak trap captures were recorded at 6 August (peak capture at 3-day intervals 20.5 males/traps). L1 larvae were found in the highest numbers on 2 August (1.5 larvae/50 cobs), practically in synchrony with peak caputres (LAG = 0). “Kama” reached R1 stage in 16 July, and L1 larvae peaked at 2 August (1.3 larvae/50 cobs) (LAG = 0). On the rest of the corn varieties larvae were found only in too numbers for performing statistical analysis. We conclude that in order to predict the appearance of L1 larvae, the phenological stage of the corn variety and the seasonal flight pattern of moths, as measured by large capacity pheromone traps, should be considered in combination. If the corn variety already reached R1 stage, L1 larvae appear on cobs as early as the time of peak flight of moths. However, no young larvae appear on cobs despite of high trap captures, until the corn reaches the R1 stage. These findings are discussed in the view of specifying optimal timing of a pesticide application.

L-Kynurenine, an amino acid identified as a sex pheromone in the urine of ovulated female masu salmon.

Many animals employ sex pheromones to find mating partners during their reproductive seasons. However, most sex pheromones of vertebrates remain to be identified. Over the past 20 years, steroids and prostaglandins have been identified as sex pheromones in several fishes. These pheromones are broadly termed "hormonal pheromones" because they or their precursors act as hormones in these fishes. Hitherto, no other type of sex pheromone has been unambiguously identified in teleost fish. Here we report the identification of a "nonhormonal pheromone" in teleost fish. The urine of the reproductively mature female masu salmon (Oncorhynchus masou) contains a male-attracting pheromone. Bioassay-guided fractionation yielded an active compound that was identical to L-kynurenine in spectral and chromatographic properties. L-Kynurenine is a major metabolite of L-tryptophan in vertebrates. This pheromone elicits a male-specific behavior at even picomolar concentrations; its electrophysiological threshold is 10(-14) M. L-Kynurenine is a reasonable substance for female masu salmon to advertise their readiness for mating.

MALE SEX PHEROMONES AND THE PHYLOGEOGRAPHIC STRUCTURE OF THE LUTZOMYIA LONGIPALPIS SPECIES COMPLEX (DIPTERA: PSYCHODIDAE) FROM BRAZIL AND VENEZUELA

Lutzomyia longipalpis, a sibling complex, is the main vector of Leishmania chagasi/infantum. Discriminating between siblings is important as they may differ in vectorial capacity. Lutzomyia longipalpis populations display distinct male sex pheromone chemotypes. We investigated the phylogeographic pattern of variation at microsatellite loci from 11 populations from Brazil and Venezuela related to their male pheromone. Temporal genetic differentiation was mostly not significant at the same site. Spatial genetic differentiation was, however, strong, although there was only a weak relationship between genetic differentiation and the geographic distance separating the samples (r2 < 0.10); geographic separation explained a much greater (54-97%) percentage of the genetic differences among populations when samples with the same pheromone type were analyzed separately. A cluster analysis showed five groups: Lu. cruzi (Brazil) and Lu. pseudolongipalpis (Venezuela) as separate species, two (mostly 9-methyl-germacrene-B) Venezuelan and Brazilian groups, and a very distinct cluster of Brazilian cembrene populations.

Sequential Learning of Pheromonal Cues Modulates Memory Consolidation in Trainer-Specific Associative Courtship Conditioning

Associative memory formation requires that animals choose predictors for experiences they need to remember. When an artificial odor is paired with an aversive experience, that odor becomes the predictor. In more natural settings, however, animals can have multiple salient experiences that need to be remembered and prioritized. The mechanisms by which animals deal with multiple experiences are incompletely understood. Here we show that Drosophila males can be trained to discriminate between different types of female pheromones; they suppress courtship specifically to the type of female that was associated with unsuccessful courtship. Such "trainer-specific" learning is mediated by hydrocarbon olfactory cues and modifies the male's processing of those cues. Animals that are unable to use olfactory cues can still learn by using other sensory modalities, but memory in this case is not specific to the trainer female's maturation state. Concurrent and serial presentation of different pheromones demonstrates that the ability to consolidate memory of pheromonal cues can be modified by the temporal order in which they appear. Suppression of memory by new learning demonstrates that the dynamics of memory consolidation are subject to plasticity in Drosophila. This type of metaplasticity is essential for navigation of experience-rich natural environments.

A Homolog of Ste6, the a -Factor Transporter in Saccharomyces cerevisiae , Is Required for Mating but Not for Monokaryotic Fruiting in Cryptococcus neoformans

Fungal pheromones function during the initial recognition stage of the mating process. One type of peptide pheromone identified in ascomycetes and basidiomycetes terminates in a conserved CAAX motif and requires extensive posttranslational modifications to become mature and active. A well-studied representative is the a-factor of Saccharomyces cerevisiae. Unlike the typical secretory pathway utilized by most peptides, an alternative mechanism involving the ATP-binding cassette transporter Ste6 is used for the export of mature a-factor. Cryptococcus neoformans, a bipolar human pathogenic basidiomycete, produces CAAX motif-containing lipopeptide pheromones in both MATa and MATalpha cells. Virulence studies with a congenic pair of C. neoformans serotype D strains have shown that MATalpha cells are more virulent than MATa cells. Characterization of the MATalpha pheromones indicated that an autocrine signaling loop may contribute to the differentiation and virulence of MATalpha cells. To further address the role of pheromones in the signaling loop, we identified a STE6 homolog in the C. neoformans genome and determined its function by gene disruption. The ste6 mutants in either mating-type background showed partially impaired mating functions, and mating was completely abolished in a bilateral mutant cross. Surprisingly, the MATalpha ste6 mutant does not exhibit a defect in monokaryotic fruiting, suggesting that the activation of the autocrine signaling loop by the pheromone is via a Ste6-independent mechanism. MFalpha pheromone itself is essential for this process and could induce the signaling response intracellularly in MATalpha cells. Our data demonstrate that Ste6 is evolutionarily conserved for mating and is not required for monokaryotic fruiting in C. neoformans.

Genetic analysis and population survey of sex pheromone variation in the adzuki bean borer moth, Ostrinia scapulalis

Sexual communication in many moths occurs between females emitting a sex pheromone and males responding to it. Females of Ostrinia scapulalis (Lepidoptera: Crambidae) show a large variation in blend ratios of the two sex pheromone components (E)- and (Z)-11-tetradecenyl acetates. E type females produce a pheromone with a high percentage of (E)-11-tetradecenyl acetate, whereas Z type females produce the opposite blend. We established laboratory cultures of E and Z types. Females of the F1 generation produced an intermediate blend (I type) in both reciprocal crosses of the E and Z cultures. Results of further crossing experiments suggested that the three pheromone types are primarily controlled by a single autosomal locus with two alleles. Also, analyses of the variation in pheromone blend within F1, backcross and F2 families suggested that other genetic factors modify the pheromone blend of the I and Z types. Investigation of the pheromone variation in natural populations at 14 localities in Japan has shown that the E type was predominant in northern Japan, whereas the pheromone was highly polymorphic in central Japan. At a locality in central Japan, the pheromone was constantly polymorphic for several years, and the pheromone type frequencies did not deviate from Hardy–Weinberg expectations, providing no evidence of selection or assortative mating between the pheromone types. Analyses of pheromone variation within families derived from feral females indicated that matings between a pair with different genotypes for pheromone production was occurring in natural populations. Overall, this study showed that the genetic basis of the pheromone variation in O. scapulalis is very similar to that in its sibling species Ostrinia nubilalis although the state of pheromone polymorphisms in natural populations appears to differ between the two species. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 84, 143–160.

Comparison of Sticky Wing and Cone Pheromone Traps for Monitoring Seasonal Abundance of Black Cutworm Adults and Larvae on Golf Courses

Black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), flight activity was monitored on three golf courses in Wisconsin by using two types of pheromone traps: the Texas cone trap and sticky wing trap. The Texas cone trap caught significantly more black cutworm males compared with the sticky wing trap, capturing almost 12-fold more males. Black cutworm males were most abundant during mid-July in 2001 and 2002, between 700 and 800 cumulative degree-days. Flight activity also was detected in early May and mid-August, but these peaks were not as pronounced as in mid-July. No definitive relationship between black cutworm flight activity and subsequent larval infestations on golf course putting greens occurred.

Insect Sex Pheromone Type Alkenes from the Seeds of Quercus robur

A combination of vacuum liquid chromatography and preparative thin layer chromatography of the combined n-hexane and dichloromethane extracts of the seeds of Quercus robur afforded two insect sex pheromone type alkenes, 5E-tetradecen-1-ol (1) and 6E-tetradecen-1-ol (2), none of which has ever been isolated from any plant sources. The structures of these alkenes were determined by spectroscopic techniques.

Efficacy of Wing Versus Delta Traps for Predicting Infestation Levels of Four Generations of the Nantucket Pine Tip Moth (Lepidoptera: Tortricidae) in the Southern United States

Abstract The use of pheromone trap catches to reliably predict damage by the Nantucket pine tip moth, Rhyacionia frustrana (Comstock), in loblolly pine (Pinus taeda L.) plantations would provide forest managers with a valuable integrated pest management tool. At 17 sites throughout four states in the southern United States, in areas where R. frustrana has four annual generations, adult moths were monitored throughout the year (2002) using two types of pheromone traps, and subsequent infestation levels were determined for each tip moth generation. Cumulative wing trap catch tallies up to published spray dates for three of four adult emergence periods were highly predictive of top whorl damage during the subsequent generation using linear regression models. Multiple linear regression that included initial average tree height as a covariate did not significantly improve model efficacy. Cumulative delta trap catch tallies up to the spray date were not predictive of subsequent damage levels for any tip moth ge...

Motivating State Workers with Entomology

In the early 1980s, my lab group was trying to determine how Spodoptera exigua (Hubner), the beet armyworm, migrated into California. At that time, the belief was that the insect migrated from northern Mexico, or perhaps from Texas (the apparent source of many of California’s problems). To document how this might be occurring, we examined pheromone trap catches of adults and related these to wind patterns and temperatures at elevations up to several thousand feet (as measured by weather balloons released twice daily from a series of military bases). This part of the study was pretty straightforward: the insects not only overwintered in southern California, but were active throughout the year and were migrating in large numbers, even when weather patterns would not facilitate movement from the south (Trumble and Baker 1984). Unfortunately we couldn’t blame Texas for this particular problem—these pests were homegrown. More troublesome was the additional part of this study in which we wanted to compare types of pheromone traps. We evaluated five very different trap designs: (1) a now standard wing trap (Pherocon 1C); (2) an omnidirectional trap patterned on those created by Sharma et al. (1973); (3) an omnidirectional trap modified with inserts that allowed adult males to enter the trap but not exit (welcome to the Hotel California); (4) a delta trap; and (5) a cone orifice trap originally described by Struble (1983) and manufactured in an early form by Hara Ltd. of Canada. We tested these traps in a series of commercial tomato or celery fields in Ventura, Motivating State Workers with Entomology

Pheromone analysis of wild female moths with a PBAN C-terminal peptide injection for an estimation of assortative mating in adzuki bean borer, Ostrinia scapulalis.

The adzuki bean borer, Ostrinia scapulalis, has distinct genetic variation in the blend of two sex pheromone components, (E)- and (Z)-11-tetradecenyl acetates. This variation is largely controlled by a single autosomal locus with two alleles, E and Z. E-type (EE) females produce a pheromone with a mean E:Z ratio at 99:1 whereas Z-type (ZZ) and I-type (ZE) produce pheromones with mean of 3:97 and 64:36, respectively. Interestingly, in many natural populations of O. scapulalis in Japan, this pheromone polymorphism appears to be stably maintained. We tried to predict the changes in relative abundance of each pheromone type by estimating the pheromone production genotype of wild females and their male mates. The pheromone titer in the wild, mated females was increased without changing the blend ratio by an injection of a peptide with pheromone biosynthesis activating activity (TKYFSPRL-NH2). The frequencies of E-, I-, and Z-types at Matsudo were 15, 52, and 33%, respectively, and did not deviate from the Hardy-Weinberg expectations. The estimated mating patterns were concordant with the assumption that no assortative mating was occurring in this population, and this is suggested as a cause of sustained polymorphism at Matsudo.

Comparative studies of female sex pheromone components and male response of the corn stalk borer Sesamia nonagrioides in three different populations.

Studies to determine possible differences in the pheromone communication system of three different populations of the corn stalk borer Sesamia nonagrioides (Lef.) in France. Spain. and Greece were carried out. The two main pheromone components (Z)-11-hexadecenyl acetate (Z11-16:Ac) and (Z)-11-hexadecenol (Z11-16:OH), were detected in all analyses with very small differences in the three populations. Among the minor components, analyzed by GC-MS on concentrated gland extracts from French and Greek origin females, (Z)-l1-hexadecenal (Z11-16:Ald) was detected in minor amounts. Wind-tunnel and field studies revealed similar a male response in the three populations to pheromone glands extracts and synthetic pheromone regardless of the female/male origin. The results do not support the assumption of the existence of different pheromone types of the corn stalk borer S. nonagrioides due to geographic isolation.

GEOGRAPHIC VARIATION IN THE PHEROMONE SYSTEM OF THE SATURNIID MOTHHEMILEUCA EGLANTERINA

The common sheep moth,Hemileuca eglanterina (Boisduval), appears to have at least two distinct pheromone types. Male moths from the population in the San Gabriel Mountains of southern California are attracted optimally to a blend ofE10,Z12-hexadeca-10,12-dien-1-yl acetate (acetate);E10,Z12-hexadeca-10,12-dien-1-ol (alcohol); andE10,Z12-hexadeca-10,12-dienal (aldehyde), whereas males from the population at Robinson Summit, northwest of Ely, Nevada, are attracted to the two-component blend of alcohol and aldehyde. Populations along the eastern edge of the Sierra Nevada Mountains are composed of individuals of both pheromone types and a type intermediate between the two. Antennae from male moths from the different pheromone types give distinctly different electroantennographic responses when challenged with blends of the pheromone components, with San Gabriel Mountains males showing a large response to acetate and lesser responses to alcohol and aldehyde. In contrast, antennae from Robinson Summit males, which are attracted to lures containing only alcohol and aldehyde, exhibit a large response to alcohol, a smaller response to aldehyde, and minimal or no response to acetate. Male moths from the eastern Sierra Nevada Mountains give antennal responses similar to those of either San Gabriel Mountains or Robinson Summit males. However, eastern Sierra populations also contain an intermediate type that does not occur in areas where the major pheromone types do not occur together. This third type may be a hybrid between the two other pheromone types, and it is attracted in approximately equal numbers to synthetic pheromone lures with and without acetate. The antennae of male moths in all populations tested responded toE10,E12-16:Ac, a major pheromone component of the congenerH. nuttalli, which is sympatric with someH. eglanterina populations, and in mostH. eglanterina populations tested, the addition ofE10,E12-16:Ac antagonized responses to otherwise attractive lure blends. Overall, the existence of different pheromone types in the differentH. eglanterina populations may represent a case of reproductive character displacement.

Molecular Phylogeny Within and Between Species of the &lt;I&gt;Archips argyrospila&lt;/I&gt; Complex (Lepidoptera: Tortricidae)

The Archips argyrospila complex consists of a series of morphologically indistinct populations with a confusing array of pheromone and host types. No phylogenetic studies on the genus Archips or any of its species groups have previously been published. We examined DNA variation in a 475 bp segment of the mitochondrial COI gene and compared 30 populations of A. argyrospila, four populations of A. mortuana, four populations of A. goyerana, and one specimen of each of four outgroup species. Among the 97 ingroup sequences obtained, there were 23 unique haplotypes and nucleotide variation at 20 sites. The monophyletic ingroup containing A. argyrospila, A. mortuana, A. goyerana and a West Coast clade was strongly supported by bootstrap values and decay indices. Host races and some pheromone types within A. argyrospila did not correspond to mtDNA variation in this analysis. Our molecular analyses supported phylogenetic and ecological interpretations of species status applied to A. goyerana but not A. mortuana, and supported the existence of a phylogenetically distinct West Coast species.

Inositol-1,4,5-trisphosphate accumulation induced by urinary pheromones in female rat vomeronasal epithelium

The mechanisms involved in pheromone-induced responses in the vomeronasal neurons, especially in mammals, are still unclear. In the present study, we examined the effects of rat urine samples containing various types of pheromones regulating gonadal functions on the accumulation of cAMP and inositol 1,4,5-trisphosphate (IP 3) in a vomeronasal membrane preparation from the female Wistar rat. Stimulation of the preparation with forskolin induced cAMP accumulation, but stimulation with urine samples excreted from the male Wistar rat, the female Wistar rat, and the male Donryu rat did not change cAMP levels. These results were consistent with the electrophysiological results showing that dialysis of a high concentration of cAMP into the vomeronasal neuron does not induce currents. Stimulation with the three urine samples induced the accumulation of IP 3 in the membrane preparation. These results are consistent with previous electrophysiological results [K. Inamura, M. Kashiwayanagi, K. Kurihara, Inositol-1,4,5-trisphosphate induces responses in receptor neurons in rat vomeronasal sensory slices, Chem. Senses 22 (1997) 93–103; K. Inamura, M. Kashiwayanagi, K. Kurihara, Blockage of urinary responses by inhibitors for IP 3-mediated pathway in rat vomeronasal sensory neurons, Neurosci. Lett. 233 (1997) 129–132]. After the treatment with Pertussis toxin (PTX), the male Wistar urine did not induce IP 3 accumulation significantly. Application of the male Wistar urine decreased ADP-ribosylation of G i with PTX, while that of the male Donryu urine decreased ADP-ribosylation of G o. Thus, the present results support a mechanism by which the responses of the rat vomeronasal neurons to urinary pheromones are mediated by IP 3, G i and/or G o.