Sublethal effects of selected insecticides on fecundity and wing dimorphism of green peach aphid (Hom., Aphididae)

Abstract

Effects of sublethal concentrations (LC25) of six insecticides (imidacloprid, rotenone, fenvalerate, abamectin, pirimicarb and azadirachtin) on fecundity and wing dimorphism of the green peach aphid, Myzus persicae (Sulzer), were studied both under laboratory and greenhouse conditions. In the laboratory, aphid reproduction reduced by 44.29% and 54.01% when rotenone and abamectin treatments were applied at sublethal dose, respectively, and sublethal fenvalerate application resulted in markedly lower average reproduction per female per day compared with control. Reproductive duration of aphid treated with abamectin significantly decreased by 44.19%. But in the greenhouse, there were no evident differences in the aphid fecundity and reproductive duration between treatments and control. Life‐table parameters also demonstrated that the six insecticides at sublethal doses did not stimulate the aphid reproductive potential. In the laboratory, after being exposed to sublethal doses of imidacloprid and fenvalerate, the proportions of alate progeny in aphid progeny were significantly higher than that of the control. In the greenhouse, percentages of alate offspring from the mother aphids treated with imidacloprid, fenvalerate and abamectin increased pronouncedly compared with control. Mortality rates of offspring in the nymphal stages from adults treated with insecticides revealed no significant changes between laboratory and greenhouse. The developmental time in days of the offspring varied in all treatments. Mechanisms of insecticide‐induced resurgence are discussed.

Assessment of physiological sublethal effects of imidacloprid on the mirid bug Apolygus lucorum (Meyer-Dür)

“…Various effects of imidacloprid on insect behavior have also been reported (Ramirez-Romero et al 2005;Han et al 2010b;He et al 2012). Studies have documented sublethal effects of imidacloprid on various agricultural pests (Zeng et al 2006;Wang et al 2008;Bao et al 2009;Bonia et al 2009;Cutler et al 2009;Yu et al 2010) but to date no information is available on potential sublethal effects of imidacloprid on mirid bugs. However, identifying and characterizing such effects could be crucial for understanding of the global effects of imidacloprid on mirid bugs and therefore for optimizing their management in crops.…”

“…Sublethal effects of insecticides could affect population dynamics (Stark and Banks 2003) through impairment to behavioral and physiological traits (Kerns and Stewart 2000;Desneux et al 2006a;Arnó and Gabarra 2011;Cabral et al 2011;Shahout et al 2011;Stara et al 2011;Han et al 2012). Studies have demonstrated that exposure to lethal or sublethal doses/concentrations of pesticides could reduce insect longevity and fecundity (Desneux et al 2006b;Zeng et al 2006;Wang et al 2008;Bao et al 2009;Biondi et al 2012;Zappalà et al 2012) and disturb key behavioral traits (Desneux et al 2004a, b;Ramirez-Romero et al 2008;Cordeiro et al 2010). However, possible positive sublethal effects of pesticides have been also reported (Desneux et al 2007).…”

Decrease in Pupation and Adult Emergence of Plutella xylostella (L.) treated with Hexaflumuron

“…Similarly, Sáenz-de-Cabezón et al (2006) stated that rm and λ of Tetranychus urticae (Koch) (Acari: Tetranychidae) decreased after being treated with the IGR triflumuron. Wang et al (2008) remarked that biological parameters of Myzus persicae (Sulzer) (Hom. : Aphididae) were influenced by imidacloprid.…”

Sublethal Effects of Imidacloprid on Bemisia tabaci (Hemiptera: Aleyrodidae) Under Laboratory Conditions

“…Hence, R. padi may probably be exposed to sublethal concentrations of insecticides under field conditions, and this may lead to sublethal effects. It is known that sublethal concentrations of insecticides can impair fundamental behavioral and physiological traits of the target insects such as activity, appetite, foraging behavior, and fecundity (Wang et al 2008a;Qu et al 2014). Sublethal concentrations of insecticides leading to pest outbreaks in the field have been reported in many pests (Reissig et al 1982;Tripathi & Sachan 1990;Zhang et al 2010).…”