Feeding behaviour and food preferences of the pest species comprising the Epilachna vigintioctopunctata (F.) complex (Col., Coccinellidae)

Abstract

Food acceptance trials involving 34 species belonging to five plant families confirm Epilachna cucurbitae Richards feeds exclusively on Cucurbitaceae and both E. 26‐punctata 26‐punctata (Boids.) and E. 28‐punctata pardalis (Boisd.) feed exclusively on Solanaceae. Leaves and fruit are preferred by the two solanivorous species. Flowers, especially pollen, are preferred by E. cucurbitae, with beetles acting as pollinating agents. This is the first record of such behaviour in a phytophagous coccinellid. Food preference is influenced by odour, taste, vision and age of plant. It is also influenced by thickness of leaves and the proportion of crude fibres, parenchymatous tissue and water content present. Feeding positions on the same or different plant species vary in darkness and daylight, but E. cucurbitae prefers the abaxial and E. 26‐punctata the adaxial side of leaves. With E. cucurbitae, there is no specific feeding period, but with E. 26‐punctata night feeding is preferred. In food preference trials, E.‐cucurbitae eat faster and can consume more food than E. 26‐punctata in a limited period of time, with one exception — potato (Solanum tuberosum) is the most preferred of all food plant species offered to the three epilachnine species. Complex trench‐cutting behaviour by E. cucurbitae, to isolate specific feeding areas of leaf from chemical defences produced by cucurbitaceous host plants, is recorded for the first time. This is the first record of such behaviour in Asian and Australasian epilachnines. Zusammenfassung Ernährungsverhalten und Nahrungsbevorzugung bei den Marienkäfern des Epilachna vigintioctopunctata (F.)‐Komplexes (Col., Coccinellidae) Ernährungsversuche mit 35 Pflanzenarten aus 5 Familien ergaben, daß Epilachna cucurbitae Rich. ausschließlich an Cucurbitaceen und E. 26‐punctata 26‐punctata (Boisd.) sowie E. 28‐punctata pardalis (Boisd.) ausschließlich an Solanaceen fressen. Dabei werden von den beiden Solanaceen‐Spezialisten die Blätter und Früchte bevorzugt. Blüten, vor allem Pollen, bevorzugt dagegen E. cucurbitae, deren Käfer somit als wichtige Blütenbestäuber fungieren. Diese Erkenntnis wurde erstmals zum Verhalten phytophager Coccinelliden gewonnen. Die Nahrungswahl wird bestimmt durch Riech‐, Tast‐ und Sehsinn des Käfers sowie das Alter der Pflanze. Sie wird weiterhin beeinflußt durch die Blattdicke sowie durch das Verhältnis zwischen Rohfasern, Parenchymgewebe und Wassergehalt. Das Ernährungsverhalten an denselben oder verschiedenen Pflanzenarten variiert je nach Dunkelheit und Tageslicht, doch bevorzugt E. cucurbitae die abaxiale und E. 26‐punctata die adaxiale Seite der Blätter. Bei E. cucurbitae gibt es keine spezifische Nahrungsaufnahme‐Periode, jedoch bevorzugt E. 26‐punctata die Nacht. Bei Nahrungswahlversuchen fraß während einer gegebenen Zeit E. cucurbitae schneller und konsumierte mehr Nahrung als E. 26‐punctata — mit einer Ausnahme: die Kartoffel (Solanum tuberusom) wurde von allen 3 Epilachna‐Arten gleich schnell und stark befressen. Sie bildete die eindeutig und allgemein...

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

“…Therefore, it was evident that the beetle mostly preferred Thamba followed by ISD 006 whereas Bijoy and BAU-2 were the least preferred hosts and remaining other brinjal varieties were moderately preferred by the beetle at three different temperature regimes. Richards and Filewood (1990) stated that host preference of E. vigintioctopunctata was influenced by odour, taste and age of plant and by thickness of leaves, proportion of crude fibers, parenchymatous tissue, and water content. They also stated that temperature has some effect on the host preference of this species of Epilachna beetle.…”

Two Cryptic Species of the Phytophagous Ladybird Beetle Epilachna vigintioctopunctata (Coleoptera: Coccinellidae) Detected by Analyses of Mitochondrial DNA and Karyotypes, and Crossing Experiments

“…The phytophagous ladybird beetle Epilachna vigintioctopunctata (Fabricius) is widespread in Asia and Australia, where it is notorious for causing severe damage to solanaceous crops such as eggplants and tomatoes (Dieke, 1947;Li and Cook, 1961;Pang and Mao, 1979;Hoang, 1983;Richards, 1983;Katakura et al, 1988;Richards and Filewood, 1990;Park and Yoon, 1991;Li, 1993;Shirai and Katakura, 1999). Furthermore, occurrence of this species on a leguminous weed Centrosema pubescens in Java and Sumatra was recently reported (Nishida et al, 1997;Shirai and Katakura, 1999).…”

How granivorous Coreus marginatus (Heteroptera: Coreidae) recognises its food

“…For this purpose, they can use photoreceptors, mechanoreceptors and/or chemoreceptors (e.g., Chapman 2003; Richards and Filewood 1990;Tol and Visser 2002) but specialised sensory hairs mediating olfactory and gustatory information seems to be the most important, particularly at close distance. Many studies have shown that host plants are recognised based on specific ratios of ubiquitous compounds (e.g., Bruce et al 2005) such as plant volatiles, which are detected by insect antennae (e.g., Chinta et al 1994;Schooley and Wiens 2003).…”