Diazinon Resistance in Different Selected Strains of <I>Chilo suppressalis</I> (Lepidoptera: Crambidae) in Northern Iran

Abstract

Asiatic rice borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), is a cosmopolitan and destructive pest in rice fields of the world. This pest was reported in 1973 in Iran, and it has since spread widely in rice, Oryza sativa L., fields throughout the country. In this study, we tried to evaluate comparative toxicity of diazinon in five colonies of C. suppressalis, collected from Babol (Ba), Amol (Am) of Mazandaran Province and Rasht (Ra), Sheikhmahale (Sh), and Gourabzarmikh (Go) of Guilan Province, northern Iran. The LD50 values were compared. We also evaluated the general esterases, alkaline phosphatase (ALP), glutathione transferase (GST), and acetylcholinesterase (AChE) activities from the five populations. The LD50 values of Ra, Ba, Am, and Sh (12.64, 11.4, 7.17, and 3.71 microg/mg larva(-1)) were 13.67-, 12.33-, 7.75-, and 4.02-fold higher than Go population (0.924 microg/mg larva(-1)). Using alpha-naphthyl acetate as substrate, the general esterase activities in Ra, Ba, Am, and Sh colonies were, respectively, 1.81-, 1.68-, 1.75-, and 1.35-fold more than those in Go population. When beta-naphthyl acetate was used as the substrate, activity ratio was measured 1.98-, 2.58-, 1.25-, and 1.24-fold compared with the Go population. Glutathione transferase activities in Ra, Ba, Am, and Sh populations were 1.27-, 1.68-, 0.98-, and 1.7-fold more than those in Go, when 1-chloro-2,4-dinitrobenzene was used as the substrate. When 1,2-dichloro-4-nitro-benzene was used as the substrate, activity ratio was measured 1.14-, 1.42-, 0.56-, and 0.95-fold compared with Go population. The ALP activity demonstrated a significant difference among these populations and in Ra, Ba, Am, and Sh larvae were 3.54-, 4.62-, 3.84-, and 2.18-fold more than Go. The AChE inhibition or I50 value was 0.19, 0.22, 0.31, 0.19, and 0.26 mM in Ra, Ba, Am, Sh and Go populations, respectively. However, the results showed no significant differences in studied colonies. These biochemical characterizations of general esterases ALP, GST, and AChE were consistent with diazinon bioassay in the five populations. It is inferred from increased esterase, alkaline phosphatase and glutathione transferase, activities that might play an important role in the increasing resistance in C. suppressalis to diazinon among these five populations.

Bioefficacy of Alpinia galanga (Zingiberaceae) Rhizome Extracts, (<I>E</I>)<I>-p</I>-Acetoxycinnamyl Alcohol, and (<I>E</I>)<I>-p</I>-Coumaryl Alcohol Ethyl Ether Against Bactrocera dorsalis (Diptera: Tephritidae) and the Impact on Detoxification Enzyme Activities

“…When the insects are attacked by these factors, the detoxification enzymes act by regulating the metabolism of hormones, pheromones, and other biologically active substances. General esterase (EST) and glutathione Stransferase (GST) are the most common enzymes involved in the detoxification of penetrated xenobiotics (Zibaee et al 2009b). In past studies, the insect resistance and activity of insect EST and GST induced by certain pesticides have been reported (Terriere 1984;Bakanova et al 1996;Feyereisen 1999;Serebrov et al 2006;Zibaee et al 2009a;Zibaee et al, 2009b).…”

“…General esterase (EST) and glutathione Stransferase (GST) are the most common enzymes involved in the detoxification of penetrated xenobiotics (Zibaee et al 2009b). In past studies, the insect resistance and activity of insect EST and GST induced by certain pesticides have been reported (Terriere 1984;Bakanova et al 1996;Feyereisen 1999;Serebrov et al 2006;Zibaee et al 2009a;Zibaee et al, 2009b). However, reports are scarce on the changes in the activity of detoxification enzymes when the insects are infected by entomopathogenic fungi and/or the fungal secondary metabolites.…”

Resistance to neurotoxic insecticides in populations of the coffee leafminer Leucoptera coffeella

“…Many studies on resistance to the organophosphate insecticide group showed high variation in the mortality of the resistant population compared to other lepidopteran populations [20,21]. Extensive insecticide use in coffee crops and high death speed are among the main factors of resistance [22].…”

Rice: Importance and Future

“…Although spraying by chemical insecticides is the main tactic to eliminate presence and damages of pests but several other tactics along with biotechnological control are used by farmers. Because of rising concerns on environmental pollution, resurgence, resistance and emerging of secondary pests caused by synthetic chemicals, researchers and farmers are seeking for safer and more efficient tactics such as using insect growth regulators, biocontrol agents, sanitation and etc [5]. For example, we have conducted several experiments to elucidate physiological efficiency of Andrallus spinidens F. (Hemiptera) and several entomopathogenic to cope population outbreaks of rice striped stem borer in Iran where it has been resistant to diazinon as common used insecticide there [6,7].…”