GC-MS analysis reveals Dendrobium candidum is a mosquito-attractant orchid with mosquitocidal compounds

Abstract
Mosquito, the infamous vector organism, is responsible for outbreaks of several deadly epidemics. Semiochemicals or pheromones and some other compounds released from several plants and animals have ability to attract mosquitoes. Heneicosane is one of such compounds reported from some plants that attracts mosquitoes, especially Aedes spp. (vector of dengue). Through our experiment based on GC-MS analysis, we report that leaf of Dendrobium candidum Wall. ex Lindl, a local orchid of Darjeeling Himalayas, is a source of heneicosane along with several other semiochemicals and odorants that can target mosquitoes. Interestingly, the orchid sample has revealed a number of components having insecticidal activities against mosquitoes which can have made this orchid a complete mosquito-bait. This research invites interest for Dendrobium candidum as a mosquito attractant and killer. For this unique property, we recommend this orchid leaf extract as a bait for dengue vector Aedes mosquito.