Phosphine resistance in Brazilian populations of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

• Published in: Journal of stored products research Vol. 45; no. 1; pp. 71 - 74
• Main Authors: Pimentel, M.A.G., Faroni, L.R.D'A., Guedes, R.N.C., Sousa, A.H., Tótola, M.R.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2009; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Brazil; carbon dioxide; Carbon dioxide production; Control; fumigant insecticides; Fumigant resistance; Fumigation; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Harvesting. Postharvest. Storage; insecticide resistance; lethal dose 50; Maize weevil; mortality; phosphine; Phytopathology. Animal pests. Plant and forest protection; Protozoa. Invertebrates; resistance mechanisms; Respiration rate; respiratory gases; Sitophilus zeamais; storage insects; toxicity; Vegetative propagation. Sowing and planting. Harvesting; Brazil; South America; America; Brazil; Respiration rate; Maize weevil; Fumigation; Fumigant resistance; Carbon dioxide production; Sitophilus zeamais; Insecticide; Coleoptera; Phosphine; Insecta; Pesticides; Carbon dioxide; Fumigant; Stored food product; Fumigant résistance; Pest; Arthropoda; Population; Curculionidae; Pesticide resistance; Invertebrata; Respiration
• ISSN: 0022-474X; 1879-1212
• DOI: 10.1016/j.jspr.2008.09.001

Phosphine resistance was assessed in adults of 22 Brazilian populations of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae). The concentration–mortality bioassays for the detection of phosphine resistance followed the FAO standard method. Twenty populations of S. zeamais were resistant to phosphine and the resistance ratios at the LC 50 ranged from 1.1- to 86.6-fold. This is the first report of phosphine resistance in populations of S. zeamais in Brazil, where previous surveys did not detect resistance in this species. There was significant variation in respiration rate (CO 2 production) among the populations ( P < 0.05). Respiration rate was significantly inversely correlated with phosphine resistance for this species ( P < 0.05). The populations with lower respiration rates showed higher levels of phosphine resistance, suggesting that the lower respiration rate is associated with the physiological basis of phosphine resistance due to reduced fumigant uptake.