OLFACTORY RESPONSES OF FEMALE OSTRINIA NUBILALIS (LEPIDOPTERA: PYRAUSTINAE)¹

Abstract

An olfactometer was constructed for measuring the oviposition responses of female moths of the European corn borer (Ostrinia nubilalis (Hbn.)) to odors from its hostplant, using the number and location of egg masses to judge the response. This olfactometer seems especially suited to examine the reactions of insects which must fly before they respond to odors. The reaction to the odor from injured plants was of special interest. Whereas the odor from uninjured plants was attractive to moths ready to lay eggs, odor from injured plants was repellent. Observations of flights of moths indicate that the repellent odor from injured plants may cause dispersal flights of adults. Zusammenfassung EIN OLFAKTOMETER ZUR PRÜFUNG DER REAKTIONEN WEIBLICHER MAISZÜNSLER, OSTRINIA NUBILALIS Ein Olfaktometer wird beschrieben, das geeignet ist, die Reaktionen weiblicher Maiszünsler auf den Duft ihrer Wirtspflanzen zu messen. Die Reaktion besteht im Absetzen von Eigelegen. Zu ihrer Beurteilung wurde Anzahl und Lokalisation der Gelege benutzt. Die Reaktion konnte so einer Interpretation mit Hilfe statistischer Testverfahren zugeführt werden. Die Versuchsanordnung scheint besonders dazu geeignet, die Reaktionen von Insekten zu prüfen, welche fliegen müssen, um auf Duftquellen reagieren zu können. Von besonderem Interesse war das Verhalten gegenüber dem Geruch verletzter Pflanzen, welcher die Maiszüns‐ler‐Weibchen von der Eiablage abhielt. Umgekehrt war der Duft unverletzter Pflanzen für Falter, die legebereit waren, anziehend. Beobachtung des Fluges der Zünsler weisen darauf hin, daß der abschreckende Duft verletzter Pflanzen Ausbreitungsflüge verursachen kann.

Effects of compost and chicken litter on soil nutrition, and sugarcane physiochemistry, yield, and injury caused by Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae)

“…In this instance, we demonstrated that heightened levels of N were associated with accumulations of free amino acids, some of them essential for insect growth and development (Vanderzant, 1958;Nation, 2002). Host plant selection among lepidopterans, including stem borers, involves visual factors such as leaf shape, color, and size (Renwick and Radke, 1988;Renwick and Chew, 1994;Showler and Castro, 2010b), but chemical cues play the major, if not decisive, role (Munakata and Okamoto, 1967;Saito and Munakata, 1970;Schur and Holdaway, 1970;Waladde, 1983;Ramaswamy, 1988). Contact chemoreceptors located on the antennae, proboscis, tarsi, and ovipositor of lepidopterans (St€ adler, 1984;Blaney and Simmonds, 1988) are instrumental in acceptance or rejection of a potential oviposition substrate based on the presence or absence of general (e.g., sugars, amino acids, vitamins) and deterrent chemicals, and moisture (Chapman, 1974;Dethier, 1980;Schoonhoven, 1981;St€ adler, 1984;Otter, 1992;Krokos et al, 2002).…”

Differences in oviposition behaviour of two sympatric sibling species of the genus Ostrinia

“…Indeed, our experimental design enabled us to examine short-range, but not long-range, responses of Ostrinia females to hostplant features. Plant volatiles are known to play an active role in attracting ECB females (Schurr & Holdaway, 1970;Cantelo & Jacobson, 1979;Lupoli et al, 1990;Binder et al, 1995), and their effects may not have been fully visible at the scale of our experiment. This would suggest that the shortrange attractivity of hop for Ostrinia is high (in our experiment, it ranked first for O. scapulalis and was second only to maize for O. nubilalis) and that the reason for its low infestation in the field is due rather to a relative lack of longrange attractivity.…”

Oviposition Behavior ofOstrinia nubilalis(Lepidoptera: Crambidae) in Response to Potential Intra- and Interspecific Interactions

“…The presence of frass has already been established as an oviposition deterrent in the laboratory over a small scale (within 30 ϫ 30 ϫ 61-cm cages) (Schurr and Holdaway 1970). Therefore, differences in egg distribution from this experiment would indicate that European corn borer females make at least some decisions about oviposition between plants in the Þeld.…”

“…Chiang et al (1960) suggested that second-generation European corn borers avoided oviposition on corn plants that had been heavily infested by Þrst-generation larvae. Laboratory evidence has corroborated this Þnding by demonstrating that females are repelled from volatiles of injured corn plants (Schurr and Holdaway 1970) and oviposition is deterred by a methanolsoluble chemical extracted from European corn borer larval frass (Dittrick et al 1983). Although these studies have shown European corn borer may choose between sites in the laboratory, there has been little work on intraspeciÞc effects on European corn borer oviposition behavior in the Þeld.…”