The effect of host nutrition on growth and development of the parasitiod wasp Venturia-Canescens

TY - JOUR

T1 - The effect of host nutrition on growth and development of the parasitiod wasp Venturia-Canescens

AU - Harvey, J.A.

AU - Harvey, I.F.

AU - Thompson, D.J.

PY - 1995

Y1 - 1995

N2 - We investigated the effect of host (Plodia interpunctella; Lepidoptera: Pyralidae) nutritional status on development of the solitary endoparasitoid, Venturia canescens (Hymenoptera: Ichneumonidae). Parasitoids from 3rd (L3) instars reared on a deficient diet during early parasitism took longer to develop and suffered higher mortality than those reared from hosts fed ad libitum although there was not a significant difference in the size of eclosing wasps from the two groups. L5 hosts reared at high density produced smaller parasitoids, which developed more rapidly than those reared from hosts from low density containers, although mortality was higher in the latter. In a separate experiment we starved groups of 10-20 hosts (parasitized as L3) daily beginning on the 4th day after parasitism, to determine the host developmental stage required for successful parasitoid development to eclosion. Parasitoid survivorship increased with length of host access to food, while the egg-to-adult parasitoid development time increased throughout the experiment. Parasitoid size decreased with increasing periods of host starvation. The successful emergence of Venturia depends upon Plodia reaching the size normally attained in the mid-5th instar, or 50-70% of the mass of healthy late 5th instars. Our results show that when earlier instars are parasitized, host growth is essential for successful parasitoid development to eclosion. Furthermore, they suggest that, for many koinobionts, host suitability may be greatly influenced by feeding rate and food quality.

AB - We investigated the effect of host (Plodia interpunctella; Lepidoptera: Pyralidae) nutritional status on development of the solitary endoparasitoid, Venturia canescens (Hymenoptera: Ichneumonidae). Parasitoids from 3rd (L3) instars reared on a deficient diet during early parasitism took longer to develop and suffered higher mortality than those reared from hosts fed ad libitum although there was not a significant difference in the size of eclosing wasps from the two groups. L5 hosts reared at high density produced smaller parasitoids, which developed more rapidly than those reared from hosts from low density containers, although mortality was higher in the latter. In a separate experiment we starved groups of 10-20 hosts (parasitized as L3) daily beginning on the 4th day after parasitism, to determine the host developmental stage required for successful parasitoid development to eclosion. Parasitoid survivorship increased with length of host access to food, while the egg-to-adult parasitoid development time increased throughout the experiment. Parasitoid size decreased with increasing periods of host starvation. The successful emergence of Venturia depends upon Plodia reaching the size normally attained in the mid-5th instar, or 50-70% of the mass of healthy late 5th instars. Our results show that when earlier instars are parasitized, host growth is essential for successful parasitoid development to eclosion. Furthermore, they suggest that, for many koinobionts, host suitability may be greatly influenced by feeding rate and food quality.

KW - VENTURIA CANESCENS

KW - PLODIA INTERPUNCTELLA

KW - HYMENOPTERA

KW - ICHNEUMONIDAE

KW - HOST QUALITY

KW - HOST NUTRITION

KW - KOINOBIONT

KW - DEVELOPMENT

KW - PARASITISM

M3 - Article

SN - 0013-8703

VL - 75

SP - 213

EP - 220

JO - Entomologia Experimentalis et Applicata

JF - Entomologia Experimentalis et Applicata

IS - 3

ER -