Influence of host origin on host choice of the parasitoid Dinarmus basalis: Does upbringing influence choices later in life?

Abstract

The aim of this study was to investigate the influence of volatile compounds from four secondary host plants on the ability of Dinarmus basalis Rond. (Hymenoptera: Pteromalidae) to locate, recognize, and parasitize its host, 4 th instar larvae or pupae of Callosobruchus maculatus F. (Coleoptera: Chrysomelidae). To examine this, strains of D. basalis were transferred from cow-pea seeds ( Vigna unguiculata (L.) Walp. (Fabales: Fabaceae)) to pigeon pea ( Cajanus cajan (L.) Millsp.) and two varieties of Bambara groundnut ( Vigna subterranea (L.) Verdc.) seeds. The ability of D. basalis females to recognize the volatile compounds emanating from their complex host plant was tested by using a Y-tube olfactometer and a three-dimensional device. The results suggest that when females have a choice between pure air and the air emanating from their com-plex host of origin, they are attracted to the air tainted by the volatile compounds they have become accustomed to. They spent significantly more time ( p < 0.0001) in the branch of the tube leading to the odorous air than in the tube leading to the pure air. When females from pigeon pea seed hosts were offered a choice between cowpea and pigeon pea seeds, all containing 4 th instar larvae, the familiar odor of pigeon pea seeds were most attractive. When females from Bambara groundnut (white and striped) seed hosts were offered a choice between cowpea and pigeon pea seeds, all containing 4 th instar larvae, they were significantly attracted to the odour of cowpea seeds. In the three-dimensional system, the females from the four strains did not appear to have any preference for a given type of seed containing 4 th instar larvae or pupae. The parasitism rate remained high on all four types of seeds used. These results show that the use of D. basalis as a biological control agent is possible in host changing situations where C. maculatus starts to attack other legumes. The results of this study also provide information supporting the behavioral plas-ticity of D. basalis . Understanding the mechanisms involved in the adaptive phenomena of biological control agents is discussed in the context of the development of adequate methods of pest control.

Assessing the impact of arthropod natural enemies on crop pests at the field scale

“…It is possible that host discrimination influences levels of parasitism observed in a target pest species, however we can not yet describe the circumstances in which this will increase or limit pest control services. Certainly for a range of parasitoid species host preference in relation to the plant species on which hosts are present has been shown (Ortiz‐Martinez et al ., ; Sankara et al ., ).…”

Aperçu de la culture du voandzou (<i>Vigna subterranea</i> (L.) Verdcourt) au Burkina Faso: enjeux et perspectives d’amélioration de sa productivité

“…Les bruches Callosobruchus subinnotatus et Callosobruchus maculatus (F.) sont des insectes qui causent des graves dommages au voandzou durant La conservation (Lale et vidal, 2003;Sankara et al, 2012). Les huiles essentielles de certaines espèces végétales (Syzgium aromaticum, Piper guineense et Zingiber officinale) sont efficaces dans la protection du voandzou en stockage contre Collosobruchus maculatus (Ajavi et Lale, 2000).…”

Identification and Evaluation of Cotton and Tomato Plant Volatiles as Attractants for Certain Lepidopterous Insect Pests

“…That the essential oils extracted form cotton leaves are more attractive than that extracted form flowers and bolls as well as tomato varieties, these results are in harmony with that of Del who recorded that potential sources of moth attractants might be used in managing Helicoverpa armiger (Hubner), include any plant which is attractive for adult nectar for aging and females for oviposition and feeding behaviors. (Sankara et al, 2014, Morrison et al, 2016 investigated that when females have a choice between pure air and the air emanating from their complex host of origin, they are attracted to the air tainted by the volatile compounds they have become accustomed to. They spent significantly more time in the branch of the tube leading to the odorous air than in the tube leading to the pure air.…”