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Carl E. Crisp
the various steps have been described and should be consulted for methodological
details and approaches to problem solving in these research areas: laboratory
screening tests (Hastings and Jones, 1976; Robertson et al., 1976; Nigam, 1978),
single-tree tests (Maksymiuk and Orchard, 1974; Merkel, 1970; Sundaram and
Hopewell, 1976), small-scale field tests (Hard, 1979; Markin et al., 1978; Granett
and Dunbar, 1975), large-scale field tests (Dewey et al., 1974; Morris, 1977;
Williams, 1973; Williams and Walton, 1968), supportive tests (Brewer and
Markin, 1978; Markin and Wilcox, 1977; Markin, 1977), safety and environmental tests (Cunningham, 1976; Kingsbury, 1976; Shea, 1979), pilot control
tests (Lyon, 1976; Ciesla, 1977; Randall, 1976; Williams et al., 1978a), and
operational tests (Randall, 1976).
7.6.1. Laboratory Testing and Evaluation
Laboratory evaluation is conducted to isolate those compounds that are most
promising for field tests and to determine potential hazards associated with each
new insecticide (Markin and Shea, 1978). Laboratory studies involve much more
than basic screening of insecticides to determine relative toxicities to target
insects. They have the following major goals:
• Determining difference between various methods of introducing the toxicant to the insect, e.g., contact and feeding.
• Establishing the response to sublethal dosing.
• Observing side effects that may be useful in insecticide application strategies, e.g., knockdown, hormone mimic actions, time-to-death.
Guidelines for this type of investigation have been reviewed (NAS, 1975c). In
addition, various specific techniques have been described (Robertson, 1978a,
1979; Robertson and Boelter, 1979b; Robertson and Kimball, 1979a; Robertson
and Rappaport, 1979; Robertson et al., 1976, 1978a, 1979).
Once colonies of the desired insects have been established (Lyon et al.,
1972a,b; Robertson, 1979) and the techniques for assessment of toxicity evaluation have been developed, the bioassay methods can be used to evaluate many
different types of toxicological parameters-topical LDso, feeding LCso , spray
chamber aerosol LCso, response of different populations to insecticides, toxicity
response of different stages of development of the same insect, genetic factors,
and insecticide resistance.
Screening procedures can be modified for bioassays to provide data for
assessing (1) residues in field samples, (2) rainfastness of test materials, and
(3) the efficacy of systemic insecticides. Large numbers of insects are required
for screening and bioassay. And they must be representative of the target insect
population found in the field.
Insects for laboratory work can be field-collected, but the research is re-
Carl E. Crisp
the various steps have been described and should be consulted for methodological
details and approaches to problem solving in these research areas: laboratory
screening tests (Hastings and Jones, 1976; Robertson et al., 1976; Nigam, 1978),
single-tree tests (Maksymiuk and Orchard, 1974; Merkel, 1970; Sundaram and
Hopewell, 1976), small-scale field tests (Hard, 1979; Markin et al., 1978; Granett
and Dunbar, 1975), large-scale field tests (Dewey et al., 1974; Morris, 1977;
Williams, 1973; Williams and Walton, 1968), supportive tests (Brewer and
Markin, 1978; Markin and Wilcox, 1977; Markin, 1977), safety and environmental tests (Cunningham, 1976; Kingsbury, 1976; Shea, 1979), pilot control
tests (Lyon, 1976; Ciesla, 1977; Randall, 1976; Williams et al., 1978a), and
operational tests (Randall, 1976).
7.6.1. Laboratory Testing and Evaluation
Laboratory evaluation is conducted to isolate those compounds that are most
promising for field tests and to determine potential hazards associated with each
new insecticide (Markin and Shea, 1978). Laboratory studies involve much more
than basic screening of insecticides to determine relative toxicities to target
insects. They have the following major goals:
• Determining difference between various methods of introducing the toxicant to the insect, e.g., contact and feeding.
• Establishing the response to sublethal dosing.
• Observing side effects that may be useful in insecticide application strategies, e.g., knockdown, hormone mimic actions, time-to-death.
Guidelines for this type of investigation have been reviewed (NAS, 1975c). In
addition, various specific techniques have been described (Robertson, 1978a,
1979; Robertson and Boelter, 1979b; Robertson and Kimball, 1979a; Robertson
and Rappaport, 1979; Robertson et al., 1976, 1978a, 1979).
Once colonies of the desired insects have been established (Lyon et al.,
1972a,b; Robertson, 1979) and the techniques for assessment of toxicity evaluation have been developed, the bioassay methods can be used to evaluate many
different types of toxicological parameters-topical LDso, feeding LCso , spray
chamber aerosol LCso, response of different populations to insecticides, toxicity
response of different stages of development of the same insect, genetic factors,
and insecticide resistance.
Screening procedures can be modified for bioassays to provide data for
assessing (1) residues in field samples, (2) rainfastness of test materials, and
(3) the efficacy of systemic insecticides. Large numbers of insects are required
for screening and bioassay. And they must be representative of the target insect
population found in the field.
Insects for laboratory work can be field-collected, but the research is re-