CHEMICAL CONTROL OF ACARID Brevipalpus phoenicis (Geijskes, 1939) (Acari-Tenuipalpidae), TRANSMITTER OF LEPROSIS IN CITRUS

Abstract

Leprosis of citrus is becoming a serious problem for a nascent citriculture of Goiás State, for this disease provokes defoliation and sometimes even death of young 'Pera' plants in forming orchard. This experiment was developed in one property with a forming orchard, located in the municipality of Leopoldo de Bulhões - Goiás. The prescribed treatments, expressed in dose per plant, of commercial product were: 1) binapacril (Acricid 40 CE, 16 ml); 2) clofentezine (Acaristop 50 SC, 2.0 ml); 3) clofentezine (Acaristop 50 SC, 3.0 ml); 4) tefluron + binapacril (Nomolt + Acricid 40 CE - 1.2 and 5.0 ml); 5) cyhexatin (Plictran 50 BR, 3.2 ml); 6) avermectin + triona (Vertirnec 18 CE + Triona B, 3.0 ml and 25 ml, respectively); 7) control. These treatments were realized in two stages. In the first, were ministered only acarid-killers; in the second, it was added foliar fertilization with formula 20-36-20, containing more Mg, S, B, Zn, Fe, Mn, Mo and Co, at dose of 10 g fertilizer/plant. Estimations were realized before and at 7, 15 and 30 days after pulverization, obtaining at 7 days the best results with treatments 3, 4, 5 and 6 with 77.95%, 77.20%, 78.11% and 80.31% of control, respectively, although it had none statistic significance. At 15 and 30 days all treatments presented results up to 75% of control. It is accentuated that in treatments 5 and 6 of the stage that received foliar fertilization the plants recovered from chlorosis with greater rapidity, when confronted with other treatments.