Spread of phosphine resistance among brazilian populations of three species of stored product insects

Abstract

-The resistance to fumigant insecticides in stored-products insects is often recorded. Several factors influence the evolution of insecticide resistance. Among these, the frequency of applications and the migration of resistant populations are of primary importance for the stored-product insects. The aim of this study was to characterize the spectrum and investigate the status of phosphine resistance in Brazil, in 13 populations of the coleoptera Tribolium castaneum Herbst (Tenebrionidae), ten populations of Rhyzopertha dominica (Fabr.) (Bostrichidae), and eight populations of Oryzaephilus surinamensis (L.) (Silvanidae). The pattern of resistance dispersion in the populations of these species was also verified. The bioassays for the detection of phosphine resistance followed the FAO standard method. To test the influence of migration in the evolution of the phosphine resistance, the difference of mortality in the discriminating concentration and the geographical distance among each pair wise combination of collection sites were correlated. None of the populations exhibited mortality above 90% in the discriminating concentration, for the three species. Mortality in the discriminating concentration increased with the geographical distance for R. dominica and O. surinamensis. However, no significant linear response was observed among the variables for T. castaneum populations. These results suggest that the dispersion of insects and the local selection are relevant in the evolution of the phosphine resistance in populations of R. dominica and O. surinamensis. In contrast, grain trade and local selection are probably the factors that determine the evolution of the phosphine resistance in populations of T. castaneum.

Effect of Hexaflumuron on Gustation and Reproduction of Adult Boll Weevil

“…However, the repetitive use of the same active component may lead to resistant insect populations and toxic residues adhering to food (Pimentel et al 2010;Tavares et al 2012). The use of botanical extracts and essential oils to control insects is increasing because these natural products present smaller effects on native fauna and flora, greater availability, and faster degradation, when compared with synthetic compounds (Tavares et al 2011;Fouad et al 2014).…”

Fumigant activity of Schinus terebinthifolius essential oil and its selected constituents against Rhyzopertha dominica

“…The monoterpenes were initially Table 1. Selected constituents selected identified in ripened and unripened fresh S. terenbinthifolius oils of the reported by Nascimento et al (2012). divided into two groups of constitutional isomers.…”

“…A large portion of studies on the insecticidal activity of essential oils report only the action of the oil without establishing a relationship between toxicity and the chemical composition or attributing the activity of the oil only to the relative toxicity of its isolated constituents (Araújo et al, 2012;Santos et al, 2013;Furtado et al, 2005). The scarcity of information on interactions among the chemical constituents and the proportions at which these compounds are found in essential oil has motivated our research group to investigate the degree of interaction among the chemical constituents individually at the same proportion at which the compounds are found in the S. terebinthifolius oil against R. dominica .…”

“…Curative control is performed with fumigant agents, especially phosphine. However, the indiscriminate use of these forms of pest control are the main reason for the emergence of resistant populations, especially the use of deltametrin (Shahid et al, 2014) and phosphine (Pimentel et al, 2010).…”

“…There are reports in the literature of the broad biological activities of the essential oil from the broad-leafed peppertree, such as antibiotic , anti-inflammatory (Jain et al, 1995), antioxidant andanti-cancer (Bendaoud et al, 2010) properties. A previous study on the insecticidal potential of this essential oil demonstrated toxicity to mosquitoes that transmit malaria [Anopheles gambiae, A. Arabiensisand and Culex quinquefasciatus (Kweka et al, 2010)], dengue fever [Aedes aegypti Santos et al, 2010)] and pests that attack stored grains [Hypothenemus hampei (Santos et al, 2013), Acanthoscelides obtectus, Zabrotes subfasciatus (Santos et al, 2007), Sitophilus oryzae and Tribolium castaneum (Mohamed and Abdelgaleil, 2008)]. Nascimento et al (2012) report that limonene is the main component of oils from ripened and unripened S. terebinthifolius fruit and found that the unripened fruit oil was more active in fumigation tests than the ripened fruit oil against the two-spotted spider mite (Tetranychus urticae).…”