<b>Influence of agrochemicals fipronil and imidacloprid on the learning behavior of <i>Apis mellifera</i> L. honeybees</b> - doi: 10.4025/actascianimsci.v35i4.18683

Abstract

ABSTRACT. Agrochemicals on crop cultivated areas is a source of contamination for bees and may cause physiological and behavioral disorders and mortality. The LD 50 of the pesticides fipronil and imidacloprid was determined and their effect on the learning behavior of Apis mellifera L. honeybee evaluated. ). The method of proboscis extension reflection (PER) and learning through citral odor evaluated their responses to food stimulation. LD 50 obtained were 0.28 ± 0.11 and 0.10 ± 0.04 μg bee -1 for fipronil and imidacloprid, respectively. The PER test showed no significant difference (p < 0.05) although agrochemicals affected the learning of bees. Insecticides fipronil and imidacloprid are extremely harmful to foraging Africanized Apis mellifera bees.Keywords: beekeeping, toxicity, lethal dose. Influência dos agroquímicos Fipronil e Imidaclopride no aprendizado de abelhasApis mellifera L. ). Para avaliar as respostas ao estímulo do alimento foi utilizado o método de reflexão de extensão da probóscide (REP) e aprendizado, utilizando odor citral. As DL 50 obtidas foram 0,28 ± 0,11 e 0,10 ± 0,04 μg abelha -1 para o Fipronil e Imidaclopride, respectivamente. O teste REP não apresentou diferenças significativas (p < 0,05); porém, os agroquímicos afetaram o aprendizado das abelhas. Dessa maneira, conclui-se que os inseticidas Imidaclopride e Fipronil são nocivos às abelhas campeiras de Apis mellifera.Palavras-chave: apicultura, toxicidade, dose letal.

Fipronil promotes motor and behavioral changes in honey bees (Apis mellifera) and affects the development of colonies exposed to sublethal doses

“…According to Johansen and Mayer [28], insecticides are considered toxic to bees when the LD50 is less than 2 mg per bee. We report similar LD50 results to those reported by Carrillo et al [29], who obtained an ingested fipronil LD50 of 0.28 mg/ bee, and Mayer and Lunden [30], who obtained a contact LD50 of 0.013 mg/bee. The higher toxicity of fipronil to honey bee workers through contact may be attributable to the lack of action of detoxification enzymes, which according to Miranda et al [20] are present in the digestive system, liver, or Malpighian tubules of the insects.…”

Toxicity and motor changes in Africanized honey bees (Apis mellifera L.) exposed to fipronil and imidacloprid

“…Insecticides are considered toxic to bees when the LD 50 is less than 2 μg per bee (Johansen and Mayer 1990). The values of ingested and contacted fipronil LD 50 presented in this study are within the ranges reported by Carrillo et al (2013) and Zaluski et al (2015). Toxicity data from Agence Nationale de Sécurité Sanitaire de l'Alimentation (France) reported LD 50 doses of ingestion and Data are presented as the median and interquartile intervals (Q1−Q3).…”

“…through contact of 0.00417 and 0.00593 µg fipronil/ bee, respectively (AgriTox Database, 2015). The ingested LD 50 values for imidacloprid are similar to those reported by Carrillo et al (2013), and the contact tests are within the ranges reported by Cresswell (2011). Suchail et al 2000reported ingested LD 50 values of imidacloprid about 0.005 µg/bee; and after contact application, the LD 50 values were approximately 0.024 µg/bee for A. m. mellifera and 0.014 µg/bee for A. m. caucasica.…”

Evaluation of Motor Changes and Toxicity of Insecticides Fipronil and Imidacloprid in Africanized Honey Bees (Hymenoptera: Apidae)

“…Higher values of LD 50 ingestion may be related to metabolization of toxic compounds due to the presence of enzymes in bees' digestive system, and Malpighian tubules (Miranda et al, 2003). LD 50 values of fipronil in Africanized honey bee foragers exposed by ingestion and contact ranged from 0.19 to 0.28 µg/bee and 0.006 to 0.012 µg/bee, respectively (Carrillo et al, 2013;Zaluski et al, 2015). For imidacloprid, LD 50 values ranged from 0.04 to 0.10 µg/bee (Suchail et al, 2001;Carrillo et al, 2013).…”

“…LD 50 values of fipronil in Africanized honey bee foragers exposed by ingestion and contact ranged from 0.19 to 0.28 µg/bee and 0.006 to 0.012 µg/bee, respectively (Carrillo et al, 2013;Zaluski et al, 2015). For imidacloprid, LD 50 values ranged from 0.04 to 0.10 µg/bee (Suchail et al, 2001;Carrillo et al, 2013). Changes in LD 50 values can occur due to the genetic variability of bees, origin of the population, methodology, and difference in detoxification ability of bees (Suchail et al, 2001).…”