Fungal Endophytes from Orchidaceae: Diversity and Applications

Fungal endophytes inhabit the internal tissues of healthy plants asymptomatically. They are known to produce a wide array of natural compounds and bioactive secondary metabolites. These valuable compounds are anti-microbial, anti-oxidant, anti-cancer and growth-promoting in nature. Their association with host plants is typically mutualistic symbiotic, which explains the symptomless nature of their infection of the host plants. Endophytes and their host plant association are inclined to benefit the host plant, with enhanced plant growth and development, as well as improving tolerance towards biotic and abiotic stresses. Of the many plant species in the world, the members of Orchidaceae are discussed here. Orchidaceae, as a large and highly diverse family of flowering plants, are well known not just for their beautiful flowers, but also for their valuable use in traditional medicine to treat many diseases. It is hypothesized that the abundance of phytochemicals in Orchidaceae contributes to their medicinal properties. And this also ignites the interest to discover the endophytes they host and the metabolites they produce. As such, endophytes from Orchidaceae are explored for their beneficial plant-growth promoting properties, as well as for their bioactive compounds. As reservoirs of natural metabolites that are still relatively untapped, fungal endophytes have massive potential to be employed in medicinal, agricultural and industrial sectors owing to their valuable attributes. This chapter reviews the diversity of fungal endophytes from the Orchidaceae family and their application in various fields attributed to the plethora of secondary metabolites and bioactive compounds produced.