Innate host habitat preference in the parasitoid Diachasmimorpha longicaudata: functional significance and modifications through learning

DF SEGURA; NUSSENBAUM AL; F DEVESCOVI; BACHMANN GUILLERMO; MM VISCARRET; CORLEY J; SM OVRUSKI; CLADERA, J

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2016

1932-6203

Parasitoids searching for polyphagous herbivores can find their hosts in a variety of habitats. Under this scenario, chemical cues from the host habitat (not related to the host) repsent poor indicators of host location. Hence, it is unlikely that naïve females show a stronresponse to host habitat cues, which would become important only if the parasitoids learassociate such cues to the host presence. This concept does not consider that habitats cvary in profitability or host nutritional quality, which according to the optimal foraging theoand the preference-performance hypothesis (respectively) could shape the way in whichparasitoids make use of chemical cues from the host habitat. We assessed innate preference in the fruit fly parasitoidDiachasmimorpha longicaudataamong chemical cues fromfour host habitats (apple, fig, orange and peach) using a Y-tube olfactometer. Contrary towhat was predicted, we found a hierarchic pattern of preference. The parasitism rate reaized on these fruit species and the weight of the host correlates positively, to some extenwith the preference pattern, whereas preference did not correlate with survival and fecunof the progeny. As expected for a parasitoid foraging for generalist hosts, habitat preferechanged markedly depending on their previous experience and the abundance of hosts.These findings suggest that the pattern of preference for host habitats is attributable to dferences in encounter rate and host quality. Host habitat preference seems to be, howevquite plastic and easily modified according to the information obtained during foraging.