Repellent Additives to Reduce Pesticide Hazards to Honeybees: Laboratory Testing

Belzunces²,

Enviro Toxic and Chemistry

et al. 2013

108

The present study was intended to evaluate the responses of enzymes in the honeybee Apis mellifera after exposure to deltamethrin, fipronil, and spinosad and their use as biomarkers. After determination of the median lethal doses (LD50), honeybees were exposed at doses of 5.07 ng/bee and 2.53 ng/bee for deltamethrin, 0.58 ng/bee and 0.29 ng/bee for fipronil, and 4.71 ng/bee and 2.36 ng/bee for spinosad (equivalent to 1/10th [LD50/10] and 1/20th [LD50/20] of the LD50, respectively). The responses of acetylcholinesterase (AChE), carboxylesterases (CaEs-1-3), glutathione-S-transferase (GST), catalase (CAT), and alkaline phosphatase (ALP) were assessed. The results showed that deltamethrin, fipronil, and spinosad modulated these biomarkers differentially. For the enzyme involved in the defense against oxidative stress, fipronil and spinosad induced CAT activity. For the remaining enzymes, 3 response profiles were identified. First, exposure to deltamethrin induced slight effects and modulated only CaE-1 and CaE-2, with opposite effects. Second, spinosad exhibited an induction profile for most of the biomarkers, except AChE. Third, fipronil did not modulate AChE, CaE-2, or GST, increased CAT and CaE-1, and decreased ALP. Thus, this set of honeybee biomarkers appears to be a promising tool to evaluate environmental and honeybee health, and it could generate fingerprints to characterize exposures to pesticides.

Section: Discussioncontrasting

confidence: 73%

Enzymatic biomarkers as tools to assess environmental quality: A case study of exposure of the honeybee Apis mellifera to insecticides

Belzunces²,

Enviro Toxic and Chemistry

et al. 2013

108

Journal of the Royal Statistical Society Series C: Applied Statistics

“…Many different chemicals have been screened for possible repellent effects, mostly in laboratory studies (Atkins et al. , 1975).…”

Section: Introductionmentioning

confidence: 99%

Modelling the Effects of Repellent Chemicals on Foraging Bees

Ridout

Faddy

Solomon

2005

Many pesticide sprays that are used for crop protection are harmful to honey-bees. It can therefore be beneficial to add to the spray chemical compounds that are repellent to bees, to discourage them from feeding on recently sprayed crops. Experiments were conducted using an artificial feeding station to assess the repellent effects of various compounds. In this system, bees arrive at the feeding station, choose between feeding dishes to which different chemicals have been added, feed for a variable period and then depart. The number of bees at each feeding dish is recorded at intervals of 1 min. We discuss the analysis of data from this type of experiment, based on a queuing theory model. Copyright 2006 Royal Statistical Society.

“…There is a fundamental limitation in a field test design because the potential effect of a repellent cannot be separated from a stimulus novelty effect (Harpaz & Lensky 1959, Atkins, Jr. et al 1975a, 1975b. It has been known for sometime that honey bees learn to associate a floral scent with nectar and that this olfactory memory is quite persistent and can develop within a single pairing of scent and nectar (Menzel et al 1993).…”

Section: Abstract -Cymbopogon Winterianus Learning Pavlovian Conditmentioning

confidence: 99%

“…Considerable effort has been directed at finding a honey bee repellent because of public safety issues (Abramson et al 1997a), the possibility of providing researchers interested in the comparative analysis of behavior with another training stimulus to complement rewarding stimuli such as sucrose (Abramson 1994), and reducing the effects of harmful agrochemicals (Atkins, Jr. et al1975a, 1975bMayer 1997).…”

Section: Abstract -Cymbopogon Winterianus Learning Pavlovian Conditmentioning

confidence: 99%

Citronella is not a Repellent to Africanized Honey Bees Apis mellifera L. (Hymenoptera: Apidae)

et al. 2009

Citronela não é Repelente para Abelhas Africanizadas Apis mellifera L. (Hymenoptera: Apidae)RESUMO -Experimentos foram realizados a fim de se investigar a repelência de citronela (Cymbopogon winterianus Jowitt) a abelhas africanizadas Apis mellifera (L.) (Hymenoptera: Apidae) no Brasil. Os resultados indicaram que citronela não foi repelente. As abelhas aprenderam facilmente a associação pavloviana entre citronela e aprendizagem. No segundo experimento a supressão condicionada foi usada para se avaliar o efeito da citronela sobre a liberação da probóscida a partir da aprendizagem e pelo estímulo utilizando sucrose. A resposta foi indistinguível quando se ofereceu às abelhas um odor diferente do que havia sido oferecido anteriormente. Os experimentos de laboratório foram confirmados em campo quando a citronela foi aplicada diretamente às abelhas que sobrevoavam as flores da área. As abelhas que receberam o odor de citronela permaneceram nas flores. O valor do potencial de avaliação do repelente usando a aprendizagem é discutido. PALAVRAS-CHAVE -Cymbopogon winterianus, aprendizagem, condicionamento pavlovianoABSTRACT -Experiments were performed investigating citronella (Cymbopogon winterianus Jowitt) as a repellent to Africanized honey bees Apis mellifera (L.) (Hymenoptera: Apidae) in Brazil. Results indicated that citronella is not a repellent. Bees exposed to a 100% concentration of citronella easily learned a Pavlovian association between citronella and feeding. In a second experiment, conditioned suppression was used to evaluate the effect of citronella on a proboscis extended by learning and by sucrose stimulation. Performance was indistinguishable from the application of a novel control odor. The laboratory experiments were confirmed in a field experiment in which citronella was applied directly to individuals foraging on a flower patch. Bees did not fly off flowers when the odor of citronella was applied directly to them relative to a control odor. The value of evaluating potential repellents using learning paradigms is discussed.