Development and survival of Orius insidiosus (Say) nymphs on encapsulated bee pollen-based diet in a Tier-I toxicity assay.
The insidious flower bug, Orius insidiosus (Say) (Heteroptera: Anthocoridae) is an important surrogate species for assessing potential effects of plant-incorporated protectants (PIPs) on nontarget heterotrophic predators. In this study, a continuous dietary exposure system was optimized by assessing the effect of diet composition and age on the survival and development of nymphs of O. insidiosus. Greater than 85% control survival and an acceptable rate of development from nymph hatching to adult was achieved using 5-d-old nymphs at test initiation and a bee pollen-based diet supplemented with 25% Ephestia eggs. There was an unacceptable level of mortality (>40%) and/or a significantly prolonged development time when nymphs were <5 d old at test initiation. When 5-d-old nymphs were fed a bee pollen diet containing 25% Ephestia eggs and 100 μg/g potassium arsenate, time-dependent mortality was observed with a median lethal time (LT50) of 4.4 d and 100% mortality was observed after 10 d of feeding, indicating the effectiveness of the test system to detect adverse effects by dietary exposure. It is recommended that well-defined 5-d-old nymphs and an encapsulated bee pollen-based diet containing 25% ground Ephestia eggs be used in a Tier-I dietary feeding exposure assay for detecting potential effects of PIPs on O. insidiosus nymphs.
Monsanto Company, Agronomic and Environmental Assessment Sciences/T2A, 800 North Lindbergh Blvd., St. Louis, MO 63167, USA. jianguo.tan@monsanto.com
Jianguo
J
Tan
Mark S
MS
Paradise
Steven L
SL
Levine
Pamela M
PM
Bachman
Joshua P
JP
Uffman
Changjian
C
Jiang
David B
DB
Carson
D000375:Aging; D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D001149:Arsenates / Q000633:toxicity; D020062:Heteroptera / Q000187:drug effects* / Q000254:growth & development; D009758:Nymph / Q000187:drug effects / Q000254:growth & development; D011058:Pollen / Q000737:chemistry; D017680:Potassium Compounds / Q000633:toxicity; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods*
D001149:Arsenates; D017680:Potassium Compounds