Field investigations on the effects of an organophosphorus pesticide, thionazin, on predacious Carabidae (Coleoptera)

Abstract

The effects of soil-applied thionazin on field populations of Carabidae were assessed in two fields of potatoes in Berkshire, England. Broadcast at 11·2 or 44·8 kg/ha in a light sandy loam soil, thionazin considerably reduced numbers of Carabids for up to eight weeks after application. Lower catches occurred again six months later when treated soils were rotavated after lifting of the potato crop; these were attributed to the exposure of Carabidae to thionazin residues which had leached into deeper layers of the soil. Dosages of 2·24 or 8·96 kg/ha applied in rows sometimes increased numbers of Carabidae trapped, possibly because of sublethal effects increasing locomotor activity. Carabidae affected most by the treatments were the small diurnally active species such as Bembidion lampros (Hbst), B. quadrimaculatum (L.), and Trechus quadristriatus (Schr.) which were also abundant at the time when the treatments were applied. Larger species such as Harpalus rufipes (Deg.), Pterostichus vulgaris (L.), P. madidus (F.) and Calathus fuscipes (Goeze) were also affected but were generally less susceptible partly because they appeared later in the season when the pesticide had partly disappeared. The rapid disappearance of thionazin from the surface 1·3 cm of soil could account for the low susceptibilities of non-burrowing species; Asaphidion flavipes (L.) which rarely burrowed was less susceptible and Harpalus aeneus (F.) which readily burrowed was more susceptible than other species of similar size.

A laboratory study of the effects of some soil-applied organophosphorus pesticides on Carabidae (Coleoptera)

“…These results are very similar to those obtained by Getzin & Rosefield (1966) and Getzin (1967) in the U.S.A. and by Pain & Skrentny (1969) in the U.K. At the highest rate of loss, i.e., at 22 °C, the " half-life " of thionazin was approximately 25 days (3-4 weeks). Although this is a fairly rapid rate of loss, thionazin might disappear even more quickly in the field because of uptake by plants and animals and breakdown by microbial activity; however, differences were not as great as expected (Critchley, 1972). Long-term effects of soil-applied pesticides on Carabidae cannot, however, be fully evaluated without additional knowledge of their effects on egg, larval and pupal stages or on other organisms eaten by Carabidae.…”

NOTES ON THE BIOLOGY AND REARING OF TWO SPECIES OF GROUND BEETLES, PTEROSTICHUS MELANARIUS AND HARPALUS PENSYLVANICUS (COLEOPTERA: CARABIDAE)

“…Van Dinther (1963), Mowat and Coaker (1967), Edwards et a l . (1970), and Critchley (1972a, b) have demonstrated that predatory carabid populations may be substantially reduced by carbarnate or organophosphorus insecticides applied for control of pest insects.…”

Are carabid beetles suitable biotic indicators of insecticide impact in potato fields?

“…Specialist species are usually more sensitive to environmental factors than generalist species (Rainio and Niemelä, 2003). The application of insecticides reduces carabid numbers in fields (Critchley, 1972b;Vickerman and Sunderland, 1977;Chiverton, 1984). Several studies have revealed that carabid abundance and species richness are higher in organic farming systems than in conventional farming systems (Dritschilo and Wanner, 1980;Cárcamo et al, 1995;Ellsbury et al, 1998;Döring and Kromp, 2003;Clark et al, 2006), although some papers have reported no difference, or even the reverse (see reviews by Holland and Luff, 2000;Hole et al, 2005).…”