Articulating Fragrant Agarwood Formation as an Outcome of the Interaction between the Insect Zeuzera conferta and Aquilaria trees – A Review

Agarwood is the resinous infected wood obtained from Aquilaria species, which is a highly priced product in the flavour and fragrance market. Its formation is a complex process of interaction between the plant, insect, and microorganisms. Multiple studies concerning the interaction of microorganisms with the Aquilaria tree have been reported. However, the significant interaction between the insect Zeuzera conferta Walker (Lepidoptera: Cossidae) with Aquilaria has been overlooked, and only exiguous studies have been accomplished. Considering the dearth of available literature on this interesting phenomenon a review has been attempted. The taxonomical and morphological descriptions proffered by researchers and the insect life cycle are discussed. The review lays emphasis on the chemical ecology of the interaction between Z. conferta, Aquilaria and associating microorganisms as a possible continuum operating in the form of complex chemical signalling via release and sensing of Volatile Organic Compounds (VOCs), Herbivore Induced Plant Volatiles (HIPVs) and Microbial Volatile Organic Compounds (MVOCs). The review also scrutinizes the future perspectives of understanding the interaction in devising suitable management strategies to prevent uncontrolled infestation and, simultaneously, develop artificial rearing technology for the insect Z. conferta as a strategy for ensuring sustainable livelihood of farmers dependent on agarwood production.