Ostrinia Scapulalis Research Articles

Genetic Basis to Divergence of Sex Pheromones in Two Closely Related Moths, Ostrinia scapulalis and O. zealis

Crossing experiments between two closely related moths, Ostrinia scapulalis and O. zealis, were conducted to gain insight into the genetic basis of the divergence of female sex pheromones. The sex pheromone of O. scapulalis comprises (E)-11- and (Z)-11-tetradecenyl acetates (E11 and Z11), and distinct genetic variation is found in the blend of components. This variation is largely controlled by a single autosomal locus with two alleles, AE(sca) and AZ(sca). E-type (AE(sca)AE(sca)) females produce a pheromone with a mean E11:Z11 ratio of 99:1, whereas Z-type (AZ(sca)AZ(sca)) and 1-type (AE(sca)AZ(sca)) females produce a pheromone with a mean of 3:97 and 64:36, respectively. O. zealis is distinctive in that it has a third pheromone component, (Z)-9-tetradecenyl acetate (Z9), in addition to E11 and Z11, and the typical blend ratio is 60:35:5 (Z9:E11:Z11). Our study revealed that Z9 production in O. zealis is mainly regulated by an autosomal recessive gene phr(zea), which is suggested to be involved in the chain-shortening of a pheromone precursor fatty acid, and linked to AE(zea), a gene corresponding to AE(sca) in O. scapulalis. A few mutations in a gene involved in pheromone production could explain the dramatic shift between a two-component pheromone communication system in O. scapulalis and a three-component system in O. zealis.

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.

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.

Two kinds of sex ratio distorters in a moth, Ostrinia scapulalis.

We surveyed female-biased sex ratio traits (SR traits) in a moth, Ostrinia scapulalis (Lepidoptera: Crambidae) from six geographic locations in Japan. A small proportion (8.3%) of females showed the SR trait. About half of them were associated with a Wolbachia infection (SRw+), whereas the remaining ones were not (SRw-). No significant differences in frequencies were detected among locations and years for either SRw+ or SRw- females. In SRw+ matrilines, the SR trait was inherited. Curing the Wolbachia infection by tetracycline at the larval stages resulted in all-male broods in the next generation. These characteristics were identical to the Wolbachia-induced SR trait observed previously in the related species Ostrinia furnacalis. The Wolbachia strain in O. scapulalis was indistinguishable from that in O. furnacalis in terms of the wsp and ftsZ gene sequences, suggesting either that infection originated from a common ancestor of the two hosts or that Wolbachia was transmitted horizontally between the host species. In SRw- matrilines, on the other hand, the SR trait was not due to bacterial infection but some other maternally inherited element, since antibiotic treatment had no effect and bacterial PCR did not give the characteristic product. In these matrilines, the SR trait occasionally failed to show, suggesting the presence of nuclear factor(s) suppressing the SR trait.

Sexual mosaics induced by tetracycline treatment in the Wolbachia-infected adzuki bean borer, Ostrinia scapulalis.

Wolbachia-infected Ostrinia scapulalis (Lepidoptera: Crambidae) females generate all-female or nearly all-female broods. Curing the infection by tetracycline treatment during larval stages results in the generation of all-male broods in the next generation. Here we show that sexually mosaic offspring are produced by Wolbachia-infected females treated with tetracycline at the adult stage. The sexual mosaics had wings that were composed of distinctive female and male sectors. Besides wings, the sexually dimorphic mid tibiae displayed an intermediate morphology in some of the mosaics. Many of the mosaic individuals had an abnormal structure of the external genitalia as well, a combination of the male uncus and the female ovipositor. We assume that Wolbachia has a feminizing effect on O. scapulalis genetic males and, hence, incomplete curing of the Wolbachia infection results in the generation of sexually mosaic individuals.

Female sex pheromone polymorphism in adzuki bean borer, Ostrinia scapulalis, is similar to that in European corn borer, O. nubilalis.

Individual analysis of the female sex pheromone of the adzuki bean borer, Ostrinia scapulalis, has shown that the sex pheromone of this species comprised (E)-11-tetradecenyl acetate (E11-14:OAc) and (Z)-11-tetradecenyl acetate (Z11-14:OAc) at variable blend ratios. The pheromone blend could be tentatively categorized into three types with respect to the proportion of E11-14:OAc: E type (94-100%, median 99.2%), Z type (0-16%, median 3.0%), and intermediate type (I type, 48-85%, median 63.7%). In addition to the identity of components, the blend ratios in the three types were similar to those of the E strain, Z strain, and hybrid of the European corn borer, O. nubilalis, respectively. This finding suggests that two closely related but morphologically distinct species, O. scapulalis and O. nubilalis, share almost the same sex pheromone communication systems. The significance of this similarity in the two sibling species is discussed.

Transfection ofWolbachiain Lepidoptera: the feminizer of the adzuki bean borerOstrinia scapulaliscauses male killing in the Mediterranean flour mothEphestia kuehniella

Two species of Lepidoptera, Ostrinia scapulalis and Ephestia kuehniella, harbour Wolbachia, which are maternally transmitted intracellular bacteria that often cause reproductive abnormalities in arthropods. While the infection in O. scapulalis causes conversion of genetic males into functional females (feminization), that in E. kuehniella induces cytoplasmic incompatibility. In the present study, we investigated the relative importance of host and Wolbachia factors in the differential expression of reproductive alterations in these insects. We transferred the Wolbachia harboured by O. scapulalis to E. kuehniella in which the original infection had been cured by tetracycline treatment. The transfected strain of E. kuehniella expressed a maternally inherited, female-biased sex ratio. Unexpectedly, two lines of evidence suggested that the sex ratio distortion was due to male killing. First, higher mortality of young larvae was observed. Second, the removal of the transferred Wolbachia resulted in the recovery of a 1:1 sex ratio, whereas the removal of a feminizer should result in a male-biased sex ratio among offspring. To the authors' knowledge, this is the first report that a single Wolbachia strain can cause two distinct sexual abnormalities in different hosts. Our observations highlighted the importance of host-Wolbachia interactions in determining the phenotype of reproductive alterations.

Identification of Sex Pheromone of Adzuki Bean Borer,Ostrinia scapulalis

By means of gas chromatography with electroantennographic detection (GC-EAD), gas chromatography–mass spectrometry (GC-MS), and a series of bioassays, (Z)-11-tetradecenyl acetate (Z11–14:OAc) and (E)-11-tetradecenyl acetate (E11–14:OAc) at a ratio of 100:3 were identified as the female sex pheromone of the adzuki bean borer,Ostrinia scapulalis. The average amounts ofZ11–14: OAc andE11–14:OAc in a single sex pheromone gland were 6.6 ± 2.4 ng and 0.2 ± 0.1 ng, respectively. In a wind-tunnel bioassay, the binary blend ofZ11- andE11–14:OAc elicited almost the same male behavioral responses as did virgin females and sex pheromone gland extract. In field trapping experiments, rubber septa impregnated with the binary blend (50 μg/septum) attracted more males than virgin females. The sex pheromone ofO. scapulalis thus turned out to be similar to that of theZ-type European corn borer,O. nubilalis, in both components and their ratio.

No Evidence for Selection in a Pheromonally Polymorphic Moth Population

Previous articleNext article No AccessNotes and CommentsNo Evidence for Selection in a Pheromonally Polymorphic Moth PopulationBengt O. Bengtsson and Christer LofstedtBengt O. Bengtsson Search for more articles by this author and Christer Lofstedt Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 136, Number 5Nov., 1990 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/285127 Views: 2Total views on this site Citations: 8Citations are reported from Crossref Copyright 1990 The University of ChicagoPDF download Crossref reports the following articles citing this article:Fotini A. Koutroumpa, Astrid T. Groot, Teun Dekker, David G. Heckel Genetic mapping of male pheromone response in the European corn borer identifies candidate genes regulating neurogenesis, Proceedings of the National Academy of Sciences 113, no.4242 (Oct 2016).https://doi.org/10.1073/pnas.1610515113J. Tabata, Y. Ishikawa Genetic Basis Regulating the Sex Pheromone Blend in Ostrinia zealis (Lepidoptera: Crambidae) and Its Allies Inferred From Crossing Experiments, Annals of the Entomological Society of America 104, no.22 (Mar 2011): 326–336.https://doi.org/10.1603/AN10124B. O. BENGTSSON, C. LÖFSTEDT Direct and indirect selection in moth pheromone evolution: population genetical simulations of asymmetric sexual interactions, Biological Journal of the Linnean Society 90, no.11 (Jan 2007): 117–123.https://doi.org/10.1111/j.1095-8312.2007.00715.xTAKUMA TAKANASHI, YONGPING HUANG, K. RYO TAKAHASI, SUGIHIKO HOSHIZAKI, SADAHIRO TATSUKI, YUKIO ISHIKAWA Genetic analysis and population survey of sex pheromone variation in the adzuki bean borer moth, Ostrinia scapulalis, Biological Journal of the Linnean Society 84, no.11 (Dec 2004): 143–160.https://doi.org/10.1111/j.1095-8312.2005.00421.xRing T. Cardé, Kenneth F. Haynes Structure of the pheromone communication channel in moths, (Jun 2004): 283–332.https://doi.org/10.1017/CBO9780511542664.009CHARLES E. LINN JR, MARIA S. YOUNG, MATTHEW GENDLE, THOMAS J. GLOVER, WENDELL L. ROELOFS Sex pheromone blend discrimination in two races and hybrids of the European corn borer moth, Ostrinia nubilalis, Physiological Entomology 22, no.33 (Sep 1997): 212–223.https://doi.org/10.1111/j.1365-3032.1997.tb01161.xWilliam J. Bell, Larry R. Kipp, Robert D. Collins The Role of Chemo-orientation in Search Behavior, (Jan 1995): 105–152.https://doi.org/10.1007/978-1-4615-1765-8_4Michael J. Stanhope, Maureen M. Connelly, Brian Hartwick Evolution of a crustacean chemical communication channel: Behavioral and ecological genetic evidence for a habitat-modified, race-specific pheromone, Journal of Chemical Ecology 18, no.1010 (Oct 1992): 1871–1887.https://doi.org/10.1007/BF02751110