Effects of allelochemicals from leachates of larvae of Leucinodes orbonalis Guenee and leaves of Brinjal, Chilli and Tomato on the foraging behaviour potential of Trichogrammatids

We studied the effects of hexane eluted allelochemicals pool (i) from larvae of Leucinodes orbonalis Guenee and (ii) leaves of brinjal (Pusa Hybrid 5) (Solanum melongena L.), chilli (WS-632) (Capsicum annum L.) and tomato (NS-563) (Solanum lycopersicum L.) during vegetative stage grown in laboratory (VSL) and field (VSF) on the foraging behaviour of three Trichogrammatids. The foraging behaviour of Trichogramma pretiosum Riley was stimulated by leachates of L. orbonalis, brinjal (VSF) and chilli (VSL and VSF), whereas that of Trichogramma japonicum Ashmead was influenced by brinjal (VSL) and tomato (VSL) leachates. The compounds present in the leachates were identified by gas chromatography-mass spectrometry (GC-MS) and were: Heptacosane (C-27) in L. orbonalis, brinjal (VSL and VSF) and chilli (VSL and VSF), Tricosane (C-23) in L. orbonalis, brinjal (VSL and VSF) and chilli (VSL) and Docosane (C-22) in brinjal (VSL), chilli (VSL and VSF) and tomato (VSL), the most preferred leachates by Trichogrammatids. Thus, these compounds could provide effective biocontrol of Lepidopteran insects in Solanaceous crops by stimulating the foraging behaviour of T. pretiosum.