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Zvjezdana Augustinovi？,Emilija Raspudi？,Marija Ivezi？,Mirjana Brme？
Poljoprivreda (Osijek) , 2005,
Abstract: European corn borer (Ostrinia nubilalis Hubner) is one of the major corn pest in the world and in Croatia. Former investigations of corn borer in Croatia covered mostly its Eastern region. In trials conducted in 1998 and 1999 the research was extended to the North Western part of Croatia too. Macro trials were carried out with corn hybrids of FAO groups 200-600 at three localities: Kri evci, Agricultural institute Osijek and at Belje PIK Karanac. In 1998 the intensity of the corn borer attack at the locality of Belje PIK Karanac was about 37.92% and in Agricultural institute Osijek 80.83%. In 1999 it varied between 37.08% at the locality of Agricultural Institute Osijek and 71.20% at the locality in Kri evci. The estimated number of holes per plant in all three localities in both years was higher than the number of caterpillars. Length of damage per plant was between 0.38 and 18.80 cm. The data showed significant differences in the intensity of damaging effects on different localities while no significant differences concerning various hybrids were found.The statistical data concerning yield in both years showed significant differences among hybrids, localities and their interactions.
Sex Pheromone Receptor Specificity in the European Corn Borer Moth, Ostrinia nubilalis  [PDF]
Kevin W. Wanner,Andrew S. Nichols,Jean E. Allen,Peggy L. Bunger,Stephen F. Garczynski,Charles E. Linn Jr.,Hugh M. Robertson,Charles W. Luetje
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0008685
Abstract: The European corn borer (ECB), Ostrinia nubilalis (Hubner), exists as two separate sex pheromone races. ECB(Z) females produce a 97:3 blend of Z11- and E11-tetradecenyl acetate whereas ECB(E) females produce an opposite 1:99 ratio of the Z and E isomers. Males of each race respond specifically to their conspecific female's blend. A closely related species, the Asian corn borer (ACB), O. furnacalis, uses a 3:2 blend of Z12- and E12-tetradecenyl acetate, and is believed to have evolved from an ECB-like ancestor. To further knowledge of the molecular mechanisms of pheromone detection and its evolution among closely related species we identified and characterized sex pheromone receptors from ECB(Z).
European Corn Borer (Ostrinia nubilalis) Induced Responses Enhance Susceptibility in Maize  [PDF]
Nicole J. Dafoe, James D. Thomas, Paul D. Shirk, Michelle E. Legaspi, Martha M. Vaughan, Alisa Huffaker, Peter E. Teal, Eric A. Schmelz
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0073394
Shannon B Olsson, Subaharan Kesevan, Astrid T Groot, Teun Dekker, David G Heckel, Bill S Hansson
BMC Evolutionary Biology , 2010, DOI: 10.1186/1471-2148-10-285
Abstract: As part of a larger study to finely map the loci responsible for pheromone communication in this species, we have reanalyzed peripheral physiology among parental, and first and second generation hybrids between the two pheromone strains using tungsten electrode electrophysiology. Our results reveal that differences in spike amplitude ratio between male pheromone-sensitive sensory neurons in O. nubilalis races are controlled, at least partially, by sex-linked genes that exhibit E-strain dominance.We propose that peripheral olfactory response in O. nubilalis may be affected both by autosomal and sex-linked genes exhibiting a cross-locus dominance effect, and suggest that the genetic basis for pheromone reception and response in the species is more closely linked than previously thought.In recent years, sensory systems have received significant attention as catalysts to establish reproductive isolation between populations [1]. Chemical signals are perhaps the most ubiquitous sensory system, mediating behaviors between systems as diverse as gametes [2], and plants [3]. The evolution of pheromone diversity is an excellent resource to evaluate the role of sensory systems in speciation, both for its prevalence among several taxa and its definitive signal [4].In insects, sex pheromones are typically blends of small numbers of volatile organic compounds (e.g. [5]). Minute changes in the ratio or identity of the blend can drastically alter the nature of the response. These characteristics result in both an extraordinary specificity in pheromone communication, as well as the potential for huge diversity in pheromone blends [4]. Sex pheromones thus provide an enticing evolutionary palette for the analysis of reproductive isolation and the development of species diversity.Perhaps the most well studied system for assessing the role of pheromone diversity in reproductive isolation is the European Corn Borer (ECB; Ostrinia nubilalis). This species consists of two sympatric races, e
Charles Linn Jr.,Marion O'Connor,Wendell Roelofs
Journal of Insect Science , 2003,
Abstract: The response of male moths from two pheromone races of the European corn borer, Ostrinia nubilalis, was measured in a flight tunnel assay to different ratios of structurally different compounds that comprise the sex pheromone of the Asian corn borer, Ostrinia furnacalis. For both O. nubilalis races, between 1 and 5% of the males completed upwind flights to two different blends of the O. furnacalis pheromone components (the 2:1 Z/E12-14:OAc female-produced blend, and a 97:3 Z/E mix), confirming that rare males exist in the O. nubilalis populations that can detect and respond to mixtures of the O. furnacalis pheromone components. Rare males that responded to the O. furnacalis blends also responded to their own O. nubilalis blends (97:3 or 1:99 Z/E11-14:OAc), indicating that rare O. nubilalis males are not preferentially sensitive to mixtures of the O. furnacalis compounds, but rather that they have a broad range of response specificity, which includes recognition of a wide range of conspecific female-produced ratios, and also recognition of heterospecific mixtures. The results support the hypothesis that saltational shifts in pheromone blend composition (Roelofs et al., 2002) can lead to the evolution of a new species-specific communication system, in part because the broad response specificity of some males includes the ability to respond in an agonistic manner to novel mixtures of compounds.
Journal of Central European Agriculture , 2002,
Abstract: The influence of different doses of ultraviolet (UV) light on the pathogenicity of entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin to the European corn borer, Ostrinia nubilalis Hbn., and radial growth of fungus was studied in laboratory conditions. The suspensions of B. bassiana isolate SK99 were exposed to UV light. Four different doses of UV light were used in the experiment. The distance between exposed suspensions and UV light source was 0.3 m. Exposure duration was 15, 30, 45 and 60 minutes (as A, B, C and D variants). Control variant SK99 and obtained variants SK99A, SK99B, SK99C and SK99D were cultivated 21 days on Sabourard-dextrose agar. The larvae of O. nubilalis were infected with dry powder consisted of mycelia and spores from fungus cultures. During 10 days, the mortality of infected larvae was evaluated. It was ascertained that UV light exposition significantly influenced the mortality effect of B. bassiana isolates to O. nubilalis larvae. Variant SK99C showed the highest level of infectivity. Radial growth of UV variants was slower with rising time of exposure. The best ability to grow possessed non-irradiated isolate SK99 and the worse variant SK99D. The difference between these two variants was significant.
Microbial Diversity in the Midguts of Field and Lab-Reared Populations of the European Corn Borer Ostrinia nubilalis  [PDF]
Eugeni Belda,Laia Pedrola,Juli Peretó,Juan F. Martínez-Blanch,Arnau Montagud,Emilio Navarro,Javier Urchueguía,Daniel Ramón,Andrés Moya,Manuel Porcar
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0021751
Journal of Central European Agriculture , 2003,
Abstract: The investigations were made in 2002 in the outskirts of two settlements: Balatonmagyaród (Zala county) and Várda (Somogy county). In the corn fields Jermy’s light- and Arco-Pheron MZ pheromone traps were placed in order to follow up the course of flight. From the material collected the corn borer specimens were isolated, then separated by sex. The generation number of the populations appearing on the respective areas, and the characteristics of the flight were determined. The meteorological data of the areas obtained from Keszthely and Kaposvár for the period concerned were compared woth the data of flight. In that way the effect of the different meteorological elements on the flight and on the trend of the female ratio could be established. The results showed the presence of two-generation corn borer populations in both places. In Balatonmagyaród the first- while in Várda the second generation proved larger. The meteorological elements significally influenced the possibility of trapping in the case of both sexes. As for the female sex ratio close correlations were found with the minimum (P=100%; r=0.297)-, maximum (P=99.9%; r=0.267)-, average (P=100%; r=0.308) temperature and precipitation (P=98.2%; r=0.187) data. Considerable asynchrony was observed between the data obtained with the two prognostic means that we ascribed to the unreliability of the pheromone trap.
Sex-Linked Pheromone Receptor Genes of the European Corn Borer, Ostrinia nubilalis, Are in Tandem Arrays  [PDF]
Yuji Yasukochi,Nami Miura,Ryo Nakano,Ken Sahara,Yukio Ishikawa
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0018843
Kerry A Geiler, Richard G Harrison
BMC Evolutionary Biology , 2010, DOI: 10.1186/1471-2148-10-112
Abstract: The Δ11 desaturase gene genealogy does not differentiate O. nubilalis pheromone strains. However, we find two distinct clades, separated by 2.9% sequence divergence, that do not sort with pheromone strain, geographic origin, or emergence time. We demonstrate that these clades do not represent gene duplicates, but rather allelic variation at a single gene locus.Analyses of patterns of variation at the Δ11 desaturase gene in ECB suggest that this enzyme does not contribute to reproductive isolation between pheromone strains (E and Z). However, our genealogy reveals two deeply divergent allelic classes. Standing variation at loci that contribute to mate choice phenotypes may permit novel pheromone mating systems to arise in the presence of strong stabilizing selection.The origin of novel sex pheromone signaling systems may play an important role in insect speciation. Insect sex pheromones are volatile compounds or mixtures of such compounds, used in many species for mate location, species recognition, and mate choice [1]. In many moths, females produce species-specific chemical cues, and males exhibit species-specific responses (both physiological and behavioral) that are important in mate finding. Males may also produce pheromones that are used by females in exercising mate choice (e.g., [2]). These chemical cues are often blends of long-chain hydrocarbons with acetate, alcohol, or aldehyde functional groups. Because pheromone biosynthetic pathways have been well characterized [3,4], it is now possible to examine how changes at the level of protein sequence or gene expression affect pheromone phenotype, patterns of mating, and ultimately, the nature and origin of barriers to gene exchange.Pheromone signaling systems are described as "highly canalized" because changes in production or response are opposed by strong selection against novel phenotypes [5,6]. Only if the same genes control signal and response (pleiotropy), or if the genes controlling these traits are tigh
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