01606naa a2200181 a 450000100080000000500110000800800410001910000240006024500990008426000090018352010620019265000150125465000100126970000260127970000130130570000210131877300850133914805572018-06-06       2002    bl uuuu     u00u1 u    #d1 aMICHEREFF FILHO, M.  aResponse to the insecticide chlorpyrifos by arthropods on maize canopy.h[electronic resource]  c2002  aWe assessed the response of maize canopy arthoropods to the insecticide chlorpyrifos. Four 0.3 ha (18 x 180 m) plots were divided into two subplots, a control and a treated area. During tasseling of the plants, the treated area was sprayed twice, with an interval of 3 days. Ten plants were sampled: 1 day before spraying, and 7, 14, 21 and 28 days after spraying. The insecticide had no effect on insect herbivores: a high density of Spodoptera frugiperda larvae was present in the treated plots. A few predator arthropod species were negatively affected by the insecticide, but their numbers or activity increased 2 weeks after the treatment of the plots. A canonical variate analysis showed no pronounced effect of the insecticide on arthropod communities: the largest variations on species abundance were related to sampling occasion. These results can be explained by the combination of the short period of chlorpyrifos residual activity on the plant surface and the great potential for recolonization of the areas by most of the monitored arthoropods.  aInseticida  aMilho1 aDELLA LUCIA, T. M. C.1 aCRUZ, I.1 aGUEDES, R. N. C.  tInternational Journal of Pest Management, Londongv. 48, n. 3, p. 203-210, 2002.