Resumo

SOZZI, Antonio; VILLA, Adriana; VAL, Luis  e  VERCHER, Rosa. Evaluation of a blast sprayer to control Aonidiella aurantii in orange, using different doses and air flow rates. Bioagro [online]. 2011, vol.23, n.2, pp.87-92. ISSN 1316-3361.

In order to evaluate the efficiency of a conventional blast sprayer for the transportation of insecticide to the interior of citrus trees, a combination of two air flow rates with two volumes of pyriproxyfen 0.05%, was tested in an orange grove. The efficiency of the applications was evaluated by analyzing the number of living individuals of A. aurantii (California red scale) present in branches and fruits of sweet orange (Citrus sinensis (L.) Osbeck) after the treatment. The design of experiments followed a randomized block design, with five treatments which consisted of two doses of insecticide mixture (2,113 and 3,132 L·ha^-1) combined with two air flow rates (65,124 and 82,008 m³·h^-1), plus a control. The increase of air flow and insecticide doses, within the evaluated limits, resulted in losses of efficiency of the product for controlling the pest. From an economic point of view (fuel saving due to lower power requirements), and an environmental standpoint (contamination reductions due to lower insecticide use and lower drift), it is advisable to apply an insecticide mixture of 2,100 L·ha^{-1 in combination with air flows of 65,000 m3}·h^-1 for optimal control of the insect.

Palavras-chave : Citrus; pest control; sprayer of chemical product; California red scale.