Abstract
Adding sugar to agricultural habitats is expected to enhance pest control by improving the longevity and physiological status of parasitoids. How a sugar diet and physiological parameters affect the host-foraging behaviour of Diadegma insulare, a parasitoid of diamondback moth larvae (Plutella xylostella), is investigated in the laboratory. Newly-emerged females are given water or sucrose-water ad libitum for 1 day, and then monitored for movement onto and away from a single cabbage leaf infested with 30 host larvae for 1 h. A significantly lower percentage of sucrose-fed females enter the host patch than those with access to only water (starved) females (60% vs. 91%). Of the females that enter the patch, fed wasps spend significantly less time in the patch than starved wasps (32.2 vs. 25.7 min) but feeding does not significantly affect oviposition rate. Fed and starved females sting six to seven larvae, and 19-29% of females superparasitize host larvae. Wasps with higher levels of fructose are less likely to enter the host patch than wasps with lower fructose levels. The lower proportion of fed wasps entering the patch may be due to a period of inactivity after sugar feeding.
Original language | English (US) |
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Pages (from-to) | 99-103 |
Number of pages | 5 |
Journal | Physiological Entomology |
Volume | 32 |
Issue number | 1 |
DOIs | |
State | Published - Mar 2007 |
Keywords
- Diadegma insulare
- Fecundity
- Host orientation
- Inactivity
- Oviposition
- Patch time
- Physiological state
- Sucrose
- Superparasitism