Evaluation of Indigenous Strains of Entomopathogenic Nematodes, in Combination with Low-Toxicity Insecticides at Low and High Dosages South American Tomato Pinworm, Tuta absoluta (Meyrick) (Lepidoptera, Gelechiidae)

Abstract

The laboratories experiments were conducted during  September, 2021 to test the pathogenicity of two EPNs species S. feltiae and H. bacteriophora at different (IJs cm^-2) concentrations against Tuta absoluta (Meyrick)(Lepidoptera, Gelechiidae). The experimental location in Department of Entomology, Nematology Laboratory, Dr. Yashwant Singh Parmar University of Horticulture and Forestry, Solan, Himachal Pradesh, India. The native isolate was obtained from soil samples, collected from survey was carried out in Mid-hills of the North Himalayas, India, to investigate the diversity and frequency of entomopathogenic nematodes (EPNs). Our objective was to evaluate the efficacy of S. feltiae (HR1) and H. bacteriophora (HR2) in combination with low-toxicity insecticides at low and high dosages to control final-instar larvae in bioassays. The use of S. feltiae+Spinosad or chlorantraniliprole caused larvae mortality of over 100% at 96 h and second bioagent H. bacteriophora+Spinosad and chlorantraniliprole mortality of over 97.50% at 96 h at the high dose and should be included as a least toxic strategy to control T. absoluta. Our results showed that T. absoluta were suitable hosts for local indigenous strains performed good potential for biological control against invasive species. In combination with low-toxicity insecticides at low and high dosages to control final-instar larvae mortality of over 100% at 96 h at the high dose and should be included as a least toxic strategy to control tomato pinworm.