GENETIC AND ENVIRONMENTAL CONTROL OF GLYCOLIC ACID OXIDASE ACTIVITY IN ECOTYPIC POPULATIONS OF TYPHA LATIFOLIA

Glycolic acid oxidase activity at 25 C in leaf homogenates of ecotypic populations of Typha latifolia varied according to native climate of the population and current growing conditions. Activity of plants grown under warm/short day conditions was positively correlated with maximum summer temperature at the site of population origin. Activity of plants grown under cool/ long day conditions was negatively correlated with length of growing season at the site of origin. Populations from sites characterized by a long growing season are much less susceptible to environmental regulation of enzymic level than populations originating in short growing season sites. Enzyme activity is not a secondary reflection of differentiation at the level of chlorophyll or cofactor concentration. Enzymic differences between ecotypic populations reflect differences in control systems at the level of protein synthesis and genetic structure.