The Geography of Phytochemical Races

2.2 Australia and New Zealand 17
Fig. 2.8 Compounds 31–40 from Zieria
1,3,5-trimethoxybenzene [39], and the open-ring monoterpene myrcene [40] as the
prominent constituents.
2.2.4 Melaleuca (Myrtaceae)
Melaleuca alternifolia (Maiden and Betche) Cheel, locally known as the Australian
“tea tree” or as “paperbark,” is a commercially important oil plant native to northeastern
New South Wales and southern Queensland. Since the concentration of 1,8-cineole
[41] (see Fig. 2.9 for structures 41–43) fi gures signifi cantly in the usefulness, and hence
value of the oil, considerable interest has been shown in locating 1,8-cineole-low populations.
Over the years, studies have revealed the existence of several chemotypes
throughout the range of the species (Penfold et al., 1948a, b; Southwell et al., 1992;
Butcher et al., 1994). The most extensive survey of the tea tree for oil composition is
the recent study by Homer et al. (2000), which involved 615 individual trees, 15 each
from 41 sites covering the entire range of the species. This range with the coordinates
28°34′48″–31°22′23″S and 151°34′53″–153°19′36″E is centered roughly near Stanthorpe,
Queensland (on the border with New South Wales) (Fig. 2.6).