The developmental strategies and related profitability of an idiobiont ectoparasitoid Sclerodermus pupariae vary with host size
Article first published online: 18 NOV 2013
© 2013 The Royal Entomological Society
Volume 39, Issue 1, pages 101–108, February 2014
How to Cite
WEI, K., TANG, Y.-L., WANG, X.-Y., CAO, L.-M. and YANG, Z.-Q. (2014), The developmental strategies and related profitability of an idiobiont ectoparasitoid Sclerodermus pupariae vary with host size. Ecological Entomology, 39: 101–108. doi: 10.1111/een.12074
- Issue published online: 7 JAN 2014
- Article first published online: 18 NOV 2013
- Manuscript Accepted: 14 AUG 2013
- Manuscript Revised: 2 AUG 2013
- Manuscript Received: 6 MAY 2013
- National Natural Science Foundation of China. Grant Number: 30972377
- GENE Award Fund
- Host suitability;
- life-history traits;
- Massicus raddei;
- Sclerodermus pupariae
- Parasitoids can encounter patches of hosts of varying sizes. Trade-offs may result in different developmental strategies and fitness characteristics in parasitoids.
- To explore developmental strategies and host suitability of a bethylid parasitoid, Sclerodermus pupariae, in relation to the size of oak long-horned beetle larvae, Massicus raddei, effects of host size on parasitoid fitness parameters were tested under laboratory conditions.
- Maternal parasitoids obtained lower rates of parasitism when inoculating small or large hosts due to early host death and parasitoid injury, respectively, indicating significant fitness costs associated with paralysing those host sizes. Host size was shown to have highly variable effects on selected fitness parameters. For maternal females, increasing initial host size led to increasing host handling time, and fertility exhibited a parabolic relationship with host size. The highest fertility was exhibited when parasitoids oviposited on medium-sized hosts.
- Host size effects were very apparent for parasitoid offspring, with the largest hosts producing later-emerging but larger females. Parasitoid offspring sex ratios in all host size classes were significantly female-biased, and exhibited a quadratic function with increasing host size. Assessment of host profitability revealed that medium-sized hosts presented the best fitness return for the parasitoids.
- The findings suggest that this bethylid parasitoid can achieve a compromise in optimisation of the two most important fitness functions when encountering an abundance of different-sized hosts.