Relative Toxicity of Parathion and Kelthane to the Predacious Mite Phytoseiulus persimilis Athias-Henriot and its Prey, Tetranychus urticae Koch, (Acarina: Phytoseiidae, Tetranychidae) in the Laboratory

Abstract

The relative toxicity of Kelthane (1,1-bis (p-chlorophenyl) -2,2,2-trichloroethanol), and parathion to Phytoseiulus persimilis Athias-Henriot and its prey, Tetranychus urticae K. (= telarius (L.)), was determined using a Potter Spray Tower. Parathion was found to be far more toxic to P. persimilis than was Kelthane. The LD50 values for Kelthane were 0.051% and 0.29% for T. urticae and P. persimilis respectively, and for parathion were 0.050% and 0.0044% respectively. The LD95 values bore a similar relationship to each other. The two materials were equally toxic to T. urticae. Therefore, use of Kelthane rather than parathion in an environment where P. persimilis and T. urticae were interacting would favour the beneficial species. The statistical aspects of the test method are discussed.

Ecology of tetranychid mites and their natural enemies: A review: I. Tetranychid enemies: Their biological characters and the impact of spray practices

“…Some of the compounds in this group that are used specifically as aearicides show some selectivity, being relatively nontoxic to phytoseiids. Hukusima (1960, 1963a, b), Daneschwar (1963), and Herne and Chant (1965) reported that dicofol has little effect on various species of phytoseiids, although in some cases, moderate or even high toxicity was evident (Giinthart and Clausen 1959;van de Vrie, 1962;Bartlett, 1964;Sanford, 1967;Sanford and Herbert, 1967). In still other cases, however, more subtle effects were apparent.…”

“…Many records show the high toxicity to phytoseiids of such compounds as parathion, malathion, azinphosmethyl, and demeton (Mac-Phee and Sanford, 1954Sanford, , 1956Sanford, , 1961Ristich, 1956;Giinthart and Clausen, 1959;Bohm, 1960;Parent, 1961;F. F. Smith, Henneberry, and Boswell, 1963;Bartlett, 1964;Herne and Chant, 1965;Downing, 1966) and to certain insect predators of mites as well (MacPhee and Sanford, 1954Sanford, , 1956Sanford, , 1961Thill 1959;Giinthart and Clausen, 1959;Bohm, 1960;Hukusima, 1960Hukusima, , 1963a Steiner, 1962;van de Vrie, 1962;Bartlett, 1963;Gratwick, 1965). Huf-faker and Spitzer (1951) and Huffaker andKennett (1953b, 1956) used parathion to eliminate two species of phytoseiids in strawberry plants as a "checkmethod" to evaluate their ability to control cyclamen mite.…”

The Female Genitalia of Four Species of Tiger Beetles (Coleoptera: Cicindelidae)

“…For the same reason the choice of acaricides is immaterial, though a number of acaricides derived from chlorinated hydrocarbons are very toxic to tetranychids yet relatively harmless to phytoseiids and insect predators (~a c~h e e and Sanford 196 1 ; Vrie 1962; Smith, Henneberry and Boswell 1963; Bartlett 1964b; Herne and Chant 1965). For the same reason the choice of acaricides is immaterial, though a number of acaricides derived from chlorinated hydrocarbons are very toxic to tetranychids yet relatively harmless to phytoseiids and insect predators (~a c~h e e and Sanford 196 1 ; Vrie 1962; Smith, Henneberry and Boswell 1963; Bartlett 1964b; Herne and Chant 1965).…”

Race Phytoseiulus Persimilis A.-H. (Acarina: Phytoseiidae)—Resistant to Organophosphorous Pesticides

“…But regardless of its good effectiveness the application of this predator was limited due to its susceptibility with respect to the ogranophosphorous pesticides used against the other pests on the vegetable crops, such as thripses, aphids and the greenhouse white fly (1,4,6,7). This made it necessary to focus our efforts on the ways of combining the application of Ph.…”