Evaluation of Spinosad Applied to Grain Commodities for the Control of Stored Product Insect Pests

Abstract

S ynthetic insecticides are the currently used pest control method that causes quick mortality of the insects but there are harmful effects of these insecticides on the health (Arthur, 1996), environment (Phillips and Throne, 2010) and on non-targeted organisms (Fields, 1992). Stored grain insects also have developed resistance to these insecticides (Wijayaratne et al., 2018;Nayak et al., 2020). As the treated grains are consumed by human, there is a need to use reduced risk insecticides as an alternate to conventional insecticides (Arthur, 2007).Addionaly, these alternative options may be proven to have no harmfull effects on the respiratory and nervous system of humans (Phillips and Throne, 2010). Spinosad is an insecticide derived from soil borne bacteria Saccharopolyspora spinosa Mertz and Yao (1990). It is registered in several countries as a grain protectant at the maximum labelled use rate of 1 mg/Kg of grain and its Maximum Residue Limit (MRL) established at 1.5 ppm (Hertlein et al., 2011). The spinosad can persist from 6-12 months on the stored grain commodities (

Treatment of Four Stored-Grain Pests with Thiamethoxam plus Chlorantraniliprole: Enhanced Impact on Different Types of Grain Commodities and Surfaces

“…Mortalities of S. oryzae, T. confusum, and C. ferrugineus were higher on barley or wheat compared to rice and maize when treated with DE and the plant extract bitterbarkomycin (BBM) [58]. The residual efficacy of spinosad against Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae), T. granarium, and T. castaneum was higher on oats, with wheat, maize, and rice following [59]. In addition to grain type, the efficacy of grain protectants is influenced by the class of the commodity.…”