Chemical cues from the coffee berry borer influence the locomotory behaviour of its bethylid parasitoids

Abstract

Cephalonomia stephanoderis and Prorops nasuta are two bethylid wasps released into several Latin American countries for classical biological control of coffee berry borer, Hypothenemus hampei, the most serious insect pest of coffee worldwide. Recent studies on the host location behaviour of these parasitoids have shown that females of both species are attracted to volatile compounds released by immature stages and dust and frass of H. hampei. In this study, we investigated the role of the contact chemicals present in dust and frass of H. hampei on the behaviour of P. nasuta and C. stephanoderis females. Parasitoids remained longer on patches treated with methanol extracts than on acetone and hexane extracts. Females spent more time on the patch treated with the methanol extract of dust and frass than on the patches treated with the methanol extract of dry coffee and methanol control. The concentration of the methanol extracts from dust and frass influenced the locomotory activity of parasitoids of both species. The time that females spent in the patch tended to increase as the concentration of the methanol extracts increased. A further experiment aimed to identify other behavioural descriptors and gain a deeper understanding of the mechanisms underlying the response of parasitoids to methanol extracts was performed. Females of both species spent more time, covered more distance, turned more (per unit time and per unit distance), and decreased their speed when they contacted patches treated with methanol extracts in comparison to patches treated with methanol control.

Olfactory responses of Theocolax elegans (Hymenoptera, Pteromalidae) females to volatile signals derived from host habitats

“…Results similar to those for S. zeamais faeces are responsible for attracting female Lariophagus distinguendus (Tang et al 2009). Faeces, as a reliable indicator of host presence, has been described as a widespread foraging cue for parasitoids (Hendry et al 1973;Henson et al 1977;Gross et al 1975;Takabayashi and Takahashi 1989;Turlings et al 1991;Agelopoulos et al 1995;Alborn et al 1995;Chiu-Alvarado et al 2010). The present results suggest that faeces could be innately used as cues for habitat preference by T. elegans females.…”

Parasitismo na população da broca-do-café Hypothenemus hampei (Ferrari) (Coleoptera: Scolytidae), pelo parasitoide Cephalonomia stephanoderis Betrem (Hymenoptera: Bethylidae)

“…m todo o mundo, em regiões onde há plantações de café, a broca-do-café é a principal praga, causando prejuízos para mais de 20 milhões de famílias de agricultores (Vega et al 2009;Chiu-alVarado et al 2010) Historicamente, a presença da broca-do-café no Brasil relaciona-se com introdução de sementes oriundas da África e de Java entre os anos de 1913 a 1924, culminando na sua disseminação por todas as zonas produtoras de café no país (laurentino & Costa 2004). Essa praga, originária do continente africano, é um pequeno coleóptero de cor preta, considerada a praga mais severa do café devido aos resultados negativos de sua ação sobre a produção cafeeira em termos quantitativo e qualitativo (damon & Valle 2002).…”

Host Kairomones Elicit Area-Restricted Search by Prorops nasuta, A Parasitoid of the Coffee Berry Borer

“…Parasitoids used in this study were reared on H. hampei as described elsewhere [5,6]. The parasitoid culture was maintained under a 12: 12 h (light:dark) photoperiod, temperature regimen ranging from 18-30 o C, and relative humidity from 60-85%.…”

“…1, Whatman, Brentford, UK) at the bottom of dish [6,7]. A circular area 3 cm in diameter was lightly drawn with a pencil in the centre of the filter paper.…”

“…Parasitoid females assess host presence and acceptability on the basis of olfactory, visual and tactile cues [4]. Previous studies have shown that the host location behavior of P. nasuta is mediated by chemical cues from dust/frass of H. hampei [5,6].…”