Orchid floral volatiles: Biosynthesis genes and transcriptional regulations

Abstract

Abstract Floral scent and colour are key trait for many floricultural crops. Floral volatiles are biologically and economically important plant derived compounds and they play vital role in pollinator attraction, plant defense and interaction with surrounding the environment. Orchidaceae is one of the largest and most widespread families of flowering plants, with more than 25,000 species. Orchids are one of the most significant plants in ecologically adopted every habitation on earth. Floral volatiles is not limited in its role to pollinator attraction, it’s widely used for perfumes, cosmetics, flavourings and therapeutic applications. Even though biochemistry of floral volatiles is still new field for investigation.Due to importance of the plant biology orchid floral scent research were deeply needed. Analysis of the biosynthesis mechanisms involved in floral scent is necessary to understand the fine-scale molecular functions and to breed to new cultivars through floral volatile genetic engineering approaches. Now a days many researchers developed floral scent models in plants. However, little is known about the pathways responsible for floral scent in orchids, due to the long life cycle and large genome size. Only some terpenoid pathways were reported in orchids. In this review, we mainly concentrated orchid floral volatile regulation and compounds synthesis responsible pathways. Moreover,we mentioned emission of orchid floral volatiles and their function in pollination ecology. This information will provide a basic information on orchid floral scent research.