Agarwood (Aquilaria sinensis) is one of the most important resin-containing plants used to produce agar around the world and it is a precious herbal medicine usually combined with other herbs. In this study, we used the Illumina sequencing technique to explore the agarwood bacterial community structure from four different incense formations of agarwood, including healthy agarwood, drilling agarwood, liquid fermentation agarwood, and insect attack agarwood. Our results showed that 20 samples of three different incense-formation methods of agarwood and healthy agarwood acquired 1,792,706 high-quality sequences. In-depth investigation showed that when the diversity of agarwood bacterial species was higher, the agarwood incense quality was higher as well. Among healthy agarwood, drilling agarwood, fermentation agarwood, and insect attack agarwood, the bacterial community structure had significant changes. Natural agarwood, such as insect attack agarwood, kept more bacterial community structure, and the incense quality was better. Furthermore, we observed that in the healthy agarwood, Amnibacterium and Delftia were the predominant bacteria. Actinoplanes, Bordetella, and Sphingobacterium were the dominant bacteria in the drilling agarwood. Additionally, Pelagibacterium and Methylovirgula were some of the main bacteria in the fermentation liquid agarwood and the insect attack agarwood, while Cellulomonas and Aeromicrobium were the dominant bacteria. This research provides a basis for further research into the underlying mechanisms of incense production, as well as the bacterial community applications of agarwood production.
Keywords: incense formation; medicinal plant; microbiota; plant–microbe interactions.