ISSN:
1570-7458
Keywords:
physical and chemical effects
;
parasitization
;
Colorado potato beetle
;
Leptinotarsa decemlineata
;
Coleoptera
;
Chrysomelidae
;
Edovum puttleri
;
Hymenoptera
;
Eulophidae
;
UV irradiation
;
host age
;
freezing
;
kairomone
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Effects of various physical and chemical treatments of Colorado potato beetle [Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)] eggs on parasitization and development of the egg parasitoid Edovum puttleri (Hymenoptera: Eulophidae) were investigated. UV irradiation did not affect host acceptance but reduced host suitability for UV exposure times ≥90 min. Susceptibility of host eggs to UV irradiation varied with host age; eggs were most vulnerable to damage from irradiation at 12, 18, and 24 h post-oviposition. The rate of parasitization also was influenced by host age. Percent parasitization was greatest in freshly laid eggs and 24–30 h old eggs. Seventy-seven percent of host eggs frozen at −20 °C (5 min) were parasitized by E. puttleri, but extended exposure of eggs to −20 °C reduced both acceptance and suitability. Host eggs that had been washed with hexane (removal of kairomone and sticky layer) also were parasitized. After 5 min of washing, application of kairomone significantly increased the rate of parasitism (from 74.7% to 88.2%), but with longer periods of washing, kairomone application had no significant effect on percent parasitism. Thus, the sticky material(s) coating the egg did not appear to be essential for parasitization to occur. Our results provide effective methods and times for treating Colorado potato beetle eggs to maximize parasitization and development of E. puttleri.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1026425813762
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