Feeding stimulants of Solanaceae-feeding lady beetle, Epilachna vigintioctomaculata (Coleoptera: Coccinellidae) from potato leaves

Abstract

Insects and plants. E. vigintioctomaculataadults were collected at Natori City, Miyagi Prefecture and their progeny were reared at 24Ϯ1°C, 16L-8D photoregime. Leaves of potato, tomato (Lycopericon esculentum), and Lycium chinense were provided as food. These plants were cultivated in the field, except for the winter season in the greenhouse of the Faculty of Agriculture, Tohoku University.Bioassay. Feeding tests were conducted with a filter paper assay (Abe and Matsuda, 2000). Test extracts were dissolved in each extracted solvent (1 g fresh leaf equivalent/ml), and a square piece of AbstractA phytophagous lady beetle, Epilachna vigintioctomaculata, feeds mainly on potato (Solanum tuberosum) leaves. The methanol extracts of potato leaves showed feeding stimulative effects on the adult of the beetle. The feeding stimulants were isolated and identified as methyl linolenate from a lipid-soluble fraction, and glucose and fructose from an aqueous fraction. Although methyl linolenate alone was inactive, it acted synergistically with sugars. Methyl linolenate maximized the feeding activity of sugars at the concentration contained in the potato leaves. It is suggested that methyl linolenate plays an important role in the host selection of E. vigintioctomaculata.

Olfactory versus Contact Cues in Host Plant Recognition of a Monophagous Chrysomelid Beetle

“…Use of just one compound might be misleading if it is not entirely specific for S. pratensis. Comparing again contact to olfaction, ours and other results indicate that in both contact (Städler & Buser, 1984;Hopkins et al, 1997;Müller & Renwick, 2001;van Loon et al, 2002;Endo et al, 2004;Tamura et al, 2004) and olfaction (Fraser et al, 2003;Bruce et al, 2005) a blend of compounds can be necessary for host plant identification.…”

“…The monophagous beetle Ceutorhynchus inaffectatus Gyllenhal (Coleoptera: Curculionidae) is stimulated by allyl-glucosinolate of its host plant, a Brassicaceae (Larsen et al, 1992), whereas cucurbitacin can be sufficient to stimulate feeding of some specialists on Cucurbitaceae (Metcalf et al, 1980;Tallamy & Krischik, 1989). However, in other species feeding is stimulated only by a mixture of several compounds (Müller & Renwick, 2001;van Loon et al, 2002), which may be inactive when offered individually, but show synergistic effects when offered together (Endo et al, 2004;Tamura et al, 2004).…”

Effect of Temperature on the Bahaviour of Epilachna Beetle (Epilachna dodecastigma Wied.) among Different Brinjal Varieties

“…As said by Dieke (1947), about one sixth of all the illustrated species of the family Coccinellidae belongs to the sub-family Epilachninae and more or less all, to a single genus namely Epilachna. They are suppose to attack especially the leaves and feed on the chlorophillous green portion and thereby preventing the synthesis of carbohydrate by the host plants due to lack of sufficient chlorophyll even though the sunlight is present (Endo et al, 2004). This pest causes serious damage to the crops of major families namely Cucurbitaceae, Leguminosae and Solanaceae of which certain crops are most affected viz.…”

Host Preference of Epilachna Beetle, Epilachna dodecastigma (Wied.) among Cucurbitaceous Vegetables

“…Plants differing in their cyanogenic capacity affect the oviposition choices by Epilachna varivestis (Ballhorn and Lieberei, 2006). Methyl linoleate plays an important role in host selection of E. vigintioctopunctata (Endo et al, 2004). In case of cucurbit crops which specifically contain cucurbitacins was reported to be acted as feeding stimulants for E. admirabilis, E. boisduvali, E. vigintioctopunctata and E. vigintioctomaculata (Abe and Matsuda, 2000).…”