Contact Toxicity of Insecticides and Biopesticides to Trichogramma Chilonis Ishii. (Hymenoptera: Trichogrammatidae) under Laboratory Condition

Integration of insecticides and biological controls is an important tactic of Integrated Pest Management (IPM). Trichogramma chilonis is a promising natural enemy of many lepidopteran insect pests. However, this hymenopteran egg parasitoid is adversely affected by most insecticides. Contact toxicity of nineteen insecticides and three biopesticides on adults of T. chilonis was investigated by using dry film residue bioassays under laboratory conditions. Profenofos and chlorpyrifos were highly lethal to the adults even at sublethal doses followed by dimethoate, spinosad, indoxacarb and acephate + imidacloprid. Diafenthiuron, nimbecidine and flubendiamide were categorised as less toxic. The biopesticides viz., Metarhizium anisopliae, Beauveria bassiana and Metarhizium rileyi were found innocuous to T. chilonis. The studysuggests that the insecticides with less toxicity and biopesticides with apparently no harmful effects on the parasitoid can be used in conjunction with parasitoids in IPM programmes. This will also advice the plant protectionists in avoiding the one with detrimental effects on this hymenopteran wasp with appropriate timing of application that controls the pests without adversely affecting their natural enemies

Trichogramma chilonis, an effective egg parasitoid for control of white stem borer Scirpophaga innotata (Walker), (Lepidoptera: Pyralidae) in rice

Rice an important staple food crop of the world, which is attacked by the various insect pests, among them the stem borers are the most destructive pests, distributed in all rice growing areas of the world and cause the severe losses. This research investigated the efficacy of the parasitoid Trichogramma chilonis (Ishii) to control the white stem borer (Scirpophaga innotata) in rice. In this respect the field studies were conducted in lower Sindh, Pakistan for the year, Kharif - 2017 and 2018. Trichogramma egg parasitoid over 230 species are reported to have been remained in biological control of insect pests of over 200 insect species belonging to 70 different families, mainly the order Lepidoptera, Hemiptera, Orthroptera and Thysnoptera, in order to manage the white stem borer of rice the Trichogramma chilonis (Ishii) was used as a bio-control agent. The Studies revealed that T. chilonis proved an effective biocontrol strategy against white stem borer of rice. The result of this study could be useful in an integrated pest management program for the management of white stem borer of rice the Trichogramma chilonis. Keywords: Stem borer, Biocontrol, Parasitoid, Population suppression.