Susceptibility of <I>Choristoneura rosaceana</I> (Lepidoptera: Tortricidae) to Two New Reduced-Risk Insecticides

Abstract

The response of field-collected populations of the obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae), to chlorantraniliprole, spinetoram, spinosad, and azinphosmethyl was assessed using a diet incorporation bioassay. Populations of obliquebanded leafroller were collected from nine orchards in Chelan, Douglas, Grant, and Okanogan counties of Washington. The neonates of the F1 or F2 generation were used in all assays. The parameters of probit regression lines were estimated and lethal concentration ratios were calculated for all populations compared with a susceptible laboratory population. Significant variation was detected in response to all four insecticides including chlorantraniliprole and spinetoram, which had never been used in the field, lethal concentration ratios were 3.9-39.7 for azinphosmethyl, 0.5-3.6 for spinosad, 1.2-5.3 for chlorantraniliprole, and 0.5-4.1 for spinetoram. Correlation analysis indicated possibility of cross-resistance between spinosad and spinetoram, which are both members of spinosyn class. The occurrence of low but significant levels of resistance against chlorantraniliprole and spinetoram in field-collected populations of C. rosaceana before their first field application indicates that the risk of resistance evolution against these two new reduced-risk insecticides exists. However, it is likely that these low levels of resistance can be managed if the insecticides are used judiciously in conjunction with sound resistance management programs. Implications of these results for developing and implementing resistance management strategies are discussed.

Insecticide Susceptibility of Cnaphalocrocis medinalis (Lepidoptera: Pyralidae) in China

“…Interpopulational variation in susceptibility to spinosad among diamondback moths, Plutella xylostella (L.), from the United States has been reported by Zhao et al (2006). SigniÞcant variation also was detected in response to spinosad in Helicoverpa armigera (Hü bner) (Wang et al 2009); the bollworm Earias vittella F. (Ahmad and Iqbal Arif 2009); obliquebanded leafroller, Choristoneura rosaceana (Harris) (Sial et al 2010); and olive fruit ßy, Bactrocera oleae (Gmelin) (Kakani et al 2010). Low level of resistance to spinosad in sweetpotato whiteßy, Bemisia tabaci (Gennadius), was detected previously (Wang et al 2010b).…”

High Levels of Resistance to Chlorantraniliprole Evolved in Field Populations of <I>Plutella xylostella</I>

“…Narrow variations in chlorantraniliprole susceptibility (based on LC 50 ) were observed in Þeld populations of P. xylostella (Þvefold) (Wang et al 2010), Choristoneura rosaceana (5.3-fold) (Sial et al 2010), Cnaphalocrocis medinalis (5.8-fold) (Zheng et al 2011), Chilo suppressalis (9.4-fold) (Huang et al 2011), Spodoptera exigua (sixfold) , and Bemisia tabaci (Þvefold) (Li et al 2012). Limited variation of chlorantraniliprole susceptibility in pest Þeld populations suggested that there is no cross-resistance to chlorantraniliprole conferred by resistance to currently used insecticides (Wang et al 2010, Li et al 2012.…”

Teratogenic Effects of Chlorantraniliprole on chick embryos (Gallus gallus domesticus)

“…Anthranilic diamides, a new class of insecticide were expected to replace some of the conventional synthetic pyrethroid, organo-phosphate, organo-chlorine, abamectin, spinosad, indoxacarb carbamates and neonicotinoid insecticides (Cao et al, 2010;Sial et al, 2010;Wang et al, 2010). They were thought to be less toxic to non-target organisms including birds, mammals, earthworms and many other arthropods (Lahm et al, 2007;Larson et al, 2012;Bontrager, 2012) and only slightly toxic to fish (U.S. EPA, 2008) but is highly toxic to Folsomia candida and Daphnia magna, and medium to very highly toxic to several insects and crustaceans (Kraggerud et al, 2010).…”