Crystal structures and chemical composition of leaf surface wax depositions on the desert moss Syntrichia caninervis

Abstract The structures and composition of cuticular waxes deposited on the leaves of a typical desert moss, Syntrichia caninervis , were investigated. The wax crystals deposited on leaves shifted with leaf aging. The results of chemical analysis showed the main chemical components of the moss wax were fatty acids, alcohols and alkanes. Leaf aging increased the content of cuticular wax and the percentage of very long chain components, from 1150 μg g −1  DW and 13.6% in younger leaves to 2640 μg g −1  DW and 37.2% in aged leaves, respectively. Dehydration/hydration also augmented the wax content by 35.17% in juvenile leaves and by 1900% in lab-cultivated leaves after three-cycle treatments. Synthesis of hexadecanoic acid and tetracosane were predicted to be the first step of wax accumulation. The responses of cuticular waxes in crystal structure and chemical composition were recommended as a biomonitor for assessing the shift of ecological and environmental quality.