Abstract:The insect chitin synthesis inhibitors, Benzophenol urea No.3, [1-(4-chloropheny1)-3-(2-chlorobenzoy1) urea], Dimilin[1-(4-chloropheny1)-3-(2, 6-difluorobenzoy1) urea], SIR8514[2-chloro-N-[[[4-(trifluoromethoxy) pheny1] amino]carbony1] benzamide] were tested against the eggs and the larvae of the Asiatic Corn Borer (ACB), Ostrinia furnacalis Guene'e, in 198.
In the laboratory, when egg masses were dipped with Larvae-killing Urea 350-1000 ppm and Dimilin 10-250 ppm, the mortalities were 80.9-94.4% and 43.2-72.1% respectively. Larvae were dipped with 5000 ppm solution of Larvae-killing Urea 3 or Dimilin, the mortalities were 69.4% and 27.0%, respectively.
In the field plot tests, when chemicals sprayed at corn early tassel against the larvae of ACB, the effects of Larvae-killing Urea 3 13 or 20g (ai)/mu, Dimilin 2.5 or 5.0g (ai)/mu and SIR8514 2.5 or 5.0g (ai)/mu, were in reduction of damage stands 41.7, 58, 3%; 50.0, 50.0%; 70.8, 70.8%, respectively, and in erduction of the larvae, 50.0, 62.5%; 75.0, 25.0%; 100.0, 87.0%, respectively.
In the field tests, treated with a 2.5% granular formulation of Larvae-killing Urea 3 dosage 50 g/mu at corn funnel stage or sprayed with 40 or 50 g/mu of Larvae-killing Urea 3 in Yu Shu and Dong Feng County, gave a reduction of damage plants by 66.8%, 35.7% and 51.2%, respectively, and their effect were higher than B.T.
