EFFECTS OF ALDICARB AND ITS SULFOXIDE AND SULFONE ON BIOLOGY OF TYLENCHULUS-SEMIPENETRANS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 10  (1) , 100-106
Abstract
In laboratory testing, egg hatch of T. semipenetrans was stimulated at concentrations of 1 and 10 .mu.g/ml aldicarb solution and inhibited at 50 and 100 .mu.g/ml. Aldicarb was more inhibitory to egg hatch than the aldicarb sulfoxide and the aldicarb sulfone. Inhibition of hatch at the high concentration was associated with delays in the molting processes, lack of larval movement within the egg and delays in embryonic development. Nematode motility was reduced at 10, 50 and 100 .mu.g/ml of aldicarb and aldicarb sulfoxide solution and at 50 and 100 .mu.g/ml aldicarb sulfone. Male development was retarded at 10 .mu.g/ml and almost completely inhibited at 50 and 100 .mu.g/ml of the 3 chemicals. In greenhouse test female development and reproduction on roots of citrus seedlings were suppressed by aldicarb at rates of 2.6 .mu.g/ml and completely inhibited at 10.6 .mu.g/ml of soil solution during a 50 day experimental period. Under field conditions, there was little systemic movement of aldicarb into roots located outside treated areas. Aldicarb reduced nematode larvae and female adult populations in the 2nd yr after the 2nd treatment. There were no differences in egg hatch and sex ratio of citrus nematodes between treated and nontreated roots.