Seletividade de acaricidas a ovos, larvas e adultos de Ceraeochrysa cubana (Hagen,1861) (Neuroptera, Chrysopidae), em laboratorio

Abstract

The purpose of this study was to evaluate the effects of fourteen acaricides commonly used in citrus orchards on eggs, larvae, and adults of Ceraeochrysa cubana (Hagen, 1861) (Neuroptera, Chrysopidae). The trials were performed at the Insect Biology Laboratory of the Escola Superior de Agricultura de Lavras (ESAL) under temperature of 25 ±2°C, relative humidity of 70 ±10% and photophase of 12 hours. The acaricides were applied through a Potter tower after being diluted in water at the concentrations recommended for application on citrus. The egg stage was highly tolerant to all acaricides applied either by spray or immersion. The incubation period of eggs treated with flufenoxuron was extended but their vlabi1ity was not affected. Larvae and adults were highly susceptible to carbosulfan and triazophos, showing 100% mortality rates. The pyrethroid bifenthrin and fenpropathrin caused about 60% mortality to both larvae and adults. Flufenoxuron was a highly deleterious to the larval phase causing death to ali larvae at the end of each instar by inhibiting molting. All other acaricides, (dicofol, bromopropylate, tetradifon, clofentezine, buprofezin, abamectin, hexythiazox, cyhexatin, and fenibutatina oxide) were highly selective to larvae and adults at the dosages.. Flufenoxuron affected fecundity by reducing oviposition capacity and making the eggs not viable. No adverse effects on fecundity was detected for any other acaricide. The survival levels and reproductive capacity of C. cubana after one spray indicated that the acaricides carbosulfan, triazophos, and flufenoxuron as non-selective. Bifenthrin and fenpropathrin can be classified as moderately-selective, whereas the remaining acaricides as highly-selective.