Laboratory Assessment of the Potential of 16 Experimental Compounds as Soil Insecticides

Abstract

The effectiveness of 16 experimental compounds as soil insecticides was assessed under laboratory conditions. Chlorpyrifos, carbofuran, and dieldrin were included as standard insecticides. Spectrum of activity as contact insecticides was determined using 24–48 h nymphs of the field cricket, Acheta pennsylvanicus (Burmeister), 24–48 h onion maggot adults, Hylemya antiqua (Meigen), third stage darksided cutworms, Euxoa messoria (Harris), northern corn rootworm adults, Diabrotica longicornis (Say), and honeybees, Apis mellifera L. First stage crickets were used to assess the biological activity of experimental compounds relative to soil type, moisture, and temperature and also their volatility in moist sand and persistence of biological activity over a 48 week period. All of the insecticides showed broad spectrum contact activity. Twelve showed fair to very good potential in soil. Four insecticides, Shell WL 24794 (O,O-dimethyl-S-1-[3-(5-methyl-1,2,4-oxadiazolyl)] ethyl phosphorodithioate), Shell WL 25735 (O-[2-chloro-1-(2,5-dichlorophenyl) vinyl] O-methyl methylphosphonothioate), Shell WL 26738 (O-[1-(2,4-dichlorophenyl) vinyl] O-methyl ethylphosphonothioate), and chlorpyrifos-methyl showed good potential. Two others, Counter® (S-[(tert-butylthio) methyl] O,O-diethyl phosphorodithioate) and Shell WL 24073 (O-[2-chloro-1-(2,5-dichlorophenyl) vinyl] O-methyl ethylphosphonothioate) were considered to have very good potential as soil insecticides.

Sorption of organophosphorus and carbamate insecticides by soil

“…The efficacy of chlorpyrifos was reduced in soils with high organic matter content, but pH had no effect on toxicity (Whitney 1967). Harris and Turnbull (1977) found that chlorpyrifos, carbofuran, and terbufos were approximately 30 times more effective in moist sand than in moist muck. In summary, there is overwhelming evidence indicating that soil type greatly influences toxicity.…”

“…Temperature effects on insecticidal activity in soil may be less dramatic than soil moisture, but Harris and Turnbull (1977) showed positive temperature coefficients for many insecticides ranging from 3 to 30 times more effective at 32°C than at 16°C. Presumably, because adsorption is an exothermic process, higher temperatures favor desorption and increased availability of the insecticide (Harris 1972).…”

BIOLOGICAL ACTIVITY OF CHLORPYRIFOS, CHLORPYRIFOS-METHYL, PHORATE, AND COUNTER® IN SOIL

“…A previous study (Harris and Turnbull 1977) in which the potential of a number of experimental compounds as soil insecticides was assessed under laboratory conditions indicated that the biological activity of chlorpyrifos-methyl and CounterB was sufficiently promising to warrant more detailed study. Chlorpyrifos-methyl is similar in chemical structure to chlorpyrifos, the former being the 0,O-dimethyl, the latter the 0,O-diethyl form of 0-(3,5,6-trichloro-2-pyridyl) phosphorothioate.…”

Synthesis and <i>In Vitro</i> Antibacterial and Antifungal Evaluation of Quinoline Analogue Azetidin and Thiazolidin Derivatives

“…The β-lactam ring shows various biological activities such as antifungal [7,8], antibacterial [9,10], antitubercular [11,12], anticonvulsant [13], analgesic, anti-inflammatory [14], synthetic precursor for amino acids [15], antiviral [16] and many more. Variety of heterocyclic products including drugs [17,18], dyes and intermediates such as thiazol yellow, thioflavin T., thidiazuron [19], herbicides [20], insecticides [21,22] and many more attributed to possess thiazolidin-4-one.…”