干旱区生态环境知识资源中心

Triodia, an endemic Australian grass genus of 70 species inhabiting arid and monsoonal regions, is an abundant and underused biomass resource. Harsh environmental conditions have driven the evolution of adaptive extremophile traits, including uniquely high aspect ratio cellulose nanofibres (CNFs) and high hemicellulose content. In this study, we advance understanding of CNFs by comparing three Triodia species (four ecotypes) grown in their natural desert habitat or cultivated in an irrigated farm setting. We evaluated biomass production, morphological and biochemical responses to these contrasting growth environments, and analysed the properties of fabricated nanopaper to assess the impact of species and growth environment on the material properties. We hypothesised that growing Triodia plants in well-watered and fertilised cultivation would relax arid environmental cues and may result in less desirable material properties. Contrary to our hypothesis, nanopaper derived from cultivated plants showed no regression in material properties compared to plants grown in their natural habitat. For instance, we found: (1) cultivated ’soft’ species had a daily yield of greater than 2 g of dry biomass per plant; (2) three of the four ecotypes tested had higher hemicellulose contents in cultivation; (3) and with this higher hemicellulose content, the biomass proved to be more amenable to fibrillation, as cultivated plants achieved a lower average fibre diameter product. Overall, this study adds to the existing knowledge on the material properties of the Australian desert grass Triodia and the potential for production in agronomic settings. Understanding and potentially manipulating the traits of Australian desert grasses for beneficial material properties will accelerate the development of bio-based products in the future.