title: Factors influencing aversive learning in the oriental fruit fly, Bactrocera dorsalis.
abstract: Parameters such as the intensity of conditioned and unconditioned stimuli, the inter-trial interval, and starvation time can influence learning. In this study, the parameters that govern aversive learning in the oriental fruit fly, Bactrocera dorsalis, a serious pest of fruits and vegetables, were examined. Male flies were trained to associate the attractive odorant methyl eugenol, a male lure, with a food punishment, sodium chloride solution, and the conditioned suppression of the proboscis-extension response was investigated. We found that high methyl eugenol concentrations support a stronger association. With increasing concentrations of sodium chloride solution, a steady decrease of proboscis-extension response during six training trials was observed. A high level of learning was achieved with an inter-trial interval of 1-10 min. However, extending the inter-trial interval to 15 min led to reduced learning. No effect of physiological status (starvation time) on learning performance was detected, nor was any non-associative learning effect induced by the repeat presentation of odor or punishment alone. The memory formed after six training trials could be retained for at least 3 h. Our results indicate that aversive learning by oriental fruit flies can be affected by odor, punishment concentration and inter-trial interval.
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology of the Ministry of Education, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
authors.forename: J L
authors.initials: JL
authors.lastname: Liu
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology of the Ministry of Education, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
authors.forename: H L
authors.initials: HL
authors.lastname: Chen
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology of the Ministry of Education, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
authors.forename: X Y
authors.initials: XY
authors.lastname: Chen
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology of the Ministry of Education, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
authors.forename: R K
authors.initials: RK
authors.lastname: Cui
authors.affiliation: Department of Biological Chemistry and Molecular Modelling, IQAC (CSIC), Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Guerrero
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology of the Ministry of Education, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China. zengxn@scau.edu.cn.
authors.forename: X N
authors.initials: XN
authors.lastname: Zeng
mesh_terms: D000818:Animals; D001362:Avoidance Learning; D005054:Eugenol / Q000031:analogs & derivatives; D005508:Food Deprivation; D008297:Male; D009043:Motor Activity; D009812:Odorants; D055696:Olfactory Perception; D010812:Physical Stimulation; D011678:Punishment; D012965:Sodium Chloride; D033621:Tephritidae; D013997:Time Factors
chemical_list: C005223:methyleugenol; D005054:Eugenol; D012965:Sodium Chloride
keywords: Aversive learning; Bactrocera dorsalis; Methyl eugenol; Olfactory behavior; Stimulus intensity