eco friendly management measures for devastating tomato pest tuta absoluta meyrick

Abstract

Investigations on eco -friendly management measures against the devastating tomato newlinepest, Tuta absoluta (Meyrick) carried out through survey, laboratory and field experiments newlinein the Dept. of Agrl. Entomology, Tamil Nadu Agricultural University, Coimbatore during newline2016 18 are briefly reported. Field survey revealed that T. absoluta incidence was equally newlinepresent in all three districts surveyed viz., Coimbatore, Dharmapuri and Krishnagiri with newlinehigh in tomato compared to other alternate hosts like brinjal and chilli. Natural enemies newlineobserved from T. absoluta infested samples during field survey were mirid predator, newlineNesidiocoris tenuis (Reuter), and larval parasitoid Hormius sp. and Elachertus sp. Biology newlineof the test insect studied under controlled condition revealed no regional variation in the newlineperiods of various life stages of insects collected from Coimbatore, Dharmapuri and newlineKrishnagiri. T. absoluta adults mostly preferred to lay eggs on upper leaf surface maximum newlinenumber by Coimbatore population (53.4 eggs/3 leaves) followed by Dharmapuri (37.9) and newlineKrishnagiri (36.5). Cytochrome c oxidase subunit I (COI) characterization revealed that newlineDharmapuri and Krishnagiri population were closely related with NCBI accession sourced newlinefrom IARI (KY619683), New Delhi, India, whereas, the Coimbatore population with Spain newline(GU353336) and Turkey (KTO02421) population. Morphometric dimensions measured for newlinethe various stages of insect development exhibited traces of variation between the three test newlinelocations, while male genitalia characters were similar conforming the identity of the insect. newlineAmong the four parasitoids viz., Trichogramma achaea Nagaraja and Nagarkatti, T. newlinechilonis Ishii, T. dendrolimi Matsumura and T. japonicum Ashmead tested with 1:1 newlineparasitoid:host ratio against T. absoluta on different ages of eggs, the highest parasitization newlineof 98.00 per cent was by T. achaea followed T. chilonis (76.00 %) and T. japonicum newline(28.00%). T. dendrolimi did not parasitize. None of the developmental stages of T. absoluta newlinewas found