Re. Berry et al., TOXICITY OF DIFLUBENZURON IN LARVAE OF GYPSY-MOTH (LEPIDOPTERA, LYMANTRIIDAE) - EFFECTS OF HOST-PLANT, Journal of economic entomology, 86(3), 1993, pp. 809-814
Larvae of gypsy moth, Lymantria dispar (L.), reared on Douglas-fir, Ps
eudotsuga menziesii (Mirb.) Franco, were significantly more tolerant o
f both topically and orally administered diflubenzuron than were those
raised on white alder (Alnus rhombifolia Nutt.). Topical administrati
on resulted in an LD50 of 8.96 mug/g larva for larvae reared on Dougla
s-fir and 3.58 mug/g larva for larvae reared on alder. The LC50s obtai
ned with orally administered diflubenzuron were 0.38 ppm for larvae re
ared on Douglas-fir and 0.07 ppm for larvae reared on alder. Topically
treated females reared on either host and orally treated females rear
ed on alder required significantly longer to pupate than did controls,
but developmental periods of males reared on alder and both sexes rea
red on Douglas-fir were unaffected by oral treatment. Pupal weights we
re not affected by treatment in either sex, whether larvae were reared
on Douglas-fir or alder.