XYLOSE IS A MAJOR NECTAR SUGAR IN PROTEA AND FAUREA

Glucose, fructose and sucrose have been called the 'big three' and are thought to be the only major nectar sugars in flowering plants. We ha ve new found the pentose sugar xylose at concentrations of up to 39% o f total sugar in the nectar of 36 species of Protea and three species of Faurea. It is interesting that morphological similarities between t hese two genera of the Proteaceae are also reflected in the nectar com position, therefore supporting the idea that nectar sugars have value as taxonomic characters. Xylose has never been considered as a nectar sugar and little is known about its ecological significance.