L. Mcnitt et al., ASSESSING THE SAFETY OF TOXIN-PRODUCING BACULOVIRUS BIOPESTICIDES TO A NONTARGET PREDATOR, THE SOCIAL WASP POLISTES METRICUS SAY, Biological control, 5(2), 1995, pp. 267-278
Colonies of the social wasp Polistes metricus were fed uninfected Spod
optera frugiperda larvae or larvae infected with either of two toxin-e
xpressing recombinant baculoviruses or a recombinant virus containing
the reporter gene, chloramphenicol acetyltransferase (cat). One of the
toxin-expressing viruses contained a gene, tox34 encoding an insect-s
elective mite neurotoxin, TxP-I. The other contained AaIT, a gene enco
ding an insect-selective scorpion neurotoxin. Viruses used during the
first half of the study contained the heterologous genes under the con
trol of the Drosophila melanogaster HSP70 promoter, which is active co
nstitutively in cells both permissive and nonpermissive to baculovirus
infection. Viruses used during the latter half of the study contained
the heterologous genes under very late viral promoter control. No dif
ference between the wasp colonies fed uninfected S. frugiperda larvae
and the colonies fed larvae infected with the toxin-expressing viruses
was observed for the five developmental parameters tested. The presen
ce of CAT and TxP-I, the toxin encoded by tox34 was detected in wasps
fed the viruses with cat and tox34 under HSP70 promoter control, but n
o CAT activity was detected in wasps from colonies fed virus with cat
under very late viral promoter control. TxP-I-related proteins were de
tected in one group of wasps fed larvae infected with the virus contai
ning tox34 under very late viral promoter control. Promoter choice in
constructing toxin-expressing recombinant baculoviruses for biological
pest control is discussed. (C) 1995 Academic Press, Inc.