INSECTICIDE RESISTANCE IN COTTON APHID, APHIS-GOSSYPII GLOVER (HOMOPTERA, APHIDIDAE) .4. SUSCEPTIBILITY OF 4 CLONES SEPARATED FROM VIVIPARA OF FIELD POPULATIONS TO VARIOUS INSECTICIDES
Hama, H; Ando, S; Hosoda, A; Suzuki, K; Takagi, Y
Insecticide Resistance in Cotton Aphid, Aphis gossypii GLOVER (Homoptera: Aphididae) IV. Susceptibility of Four Clones Separated from Vivipara of Field Populations to Various Insecticides. Hiroshi HAMA (National Institute of Agro-Environment Sciences, Tsukuba, Ibaraki 305, Japan), Sachio ANDO(3) (Chugoku National Agricultural Experiment Station, Fukuyama, Hiroshima 721, Japan), Akio HOSODA (Hiroshima Prefectural Agricultural Research Center, Higashihiroshima, Hiroshima 739-01,Japan), Ken SUZUKI (National Institute of Agro-Environment Sciences, Tsukuba, Ibaraki 305, Japan), and Yutaka TAKAGI(4) (Istitute of Japan Plant Protection Association, Ushiku, Ibaraki 300-12, Japan). Jpn. J. Appl. Entomol. Zool. 39: 117-125 (1995)The susceptibility of four clones of the cotton aphid, Aphis gossypii, which were separated from vivipara of field populations on the basis of aliesterase activity, to organophosphorus, carbamate and pyrethroid insecticides was determined by two insect body dip methods: the standard method (keeping insects in case used for dipping), and the transfer method (transfering dipped insects into clean case). The LC(50) of each insecticide determined using the transfer method was more than ten times higher than that using the standard method. Although the susceptibility of a susceptible strain (S) differed between organophosphorus insecticides, it was especially susceptible to chlorpyrifos-methyl, phosalone, and profenofos. Resistant strains with high aliesterase activity exhibited up to ten times higher resistance to most organophosphorus insecticides. The resistance ratios were especially high for thiometon, oxydeprofos, and phosalone, but, not sc high for chlorpyrifos-methyl and profenofos. Organophosphare-resistant strains also exhibited resistance to carbamate insecticides. Resistance ratios were high for ethiofencarb and pirimicarb, but moderate to carbaryl and methomyl. Some combinations of organophosphorus and carbamate insecticides, such as malathion plus carbaryl exhibited synergism for resistant strains, but not for S strains. AU tested clones were susceptible to pyrethroid insecticides.
