Life on a Leaf: Bacterial Epiphytes of a Salt-Excreting Desert Tree

The surfaces of aboveground parts of plants – the phyllosphere – are normally colonized by a variety of bacteria, yeasts, and fungi (Lindow and Leveau, 2002). Bacteria are the most numerous colonists of leaves, often being found in numbers averaging 106–107 cells/cm2 of leaf (Andrews and Harris, 2000; Beattie and Lindow, 1995; Hirano and Upper, 1989). In spite of their worldwide distribution (Morris and Kinkel, 2002), studies of the composition of bacterial communities on leaves have been relatively limited in scope, mostly focusing on potential pathogens of agriculturally relevant plants (Beattie and Lindow, 1994; Dik, et al., 1992; Ercolani, 1991).