Triterpene methyl ethers inChionochloa(Gramineae): Distribution in western South Island, New Zealand

Abstract

Abstract Earlier investigations of infraspecific triterpene methyl ether chemodemes of Chionochloa in western South Island left some uncertainty about geographic limits. Further sampling shows that the ,β-amyrin methyl ether chemodeme of C. rigida extends from southern Fiordland to Alex Knob in Westland; in C. pallens the miliacin chemodeme extends from the head of Lake Wakatipu to the Paparoa Range, and the Fiordland cycloartenol methyl ether chemodeme is recognised about as far north as Milford Sound. The range of the cycloartenol methyl ether chemodeme of C. rubra is extended to include the Paparoa Range, and into Canterbury under the Main Divide. Constancy in triterpene methyl ether synthesis is confirmed for C. pungens on Stewart I., and for C. rubra from the Volcanic Plateau. Chionochloa elata is recognised as a species, and although it synthesises miliacin is not absolutely constant in this. Natural hybrids show independent gene action controlling triterpene methyl ether synthesis.