Carbohydrate Concentration of Heath Plants of Different Geographical Origin

Abstract

(1) The carbohydrate concentration of green shoots of Calluna vulgaris, Erica tetralix and E. cinerea was sampled in early and late winter and in late summer, in plants of different geographical origin grown under similar conditions. (2) When seasonal differences were allowed for, the carbohydrate concentration of Calluna and Erica cinerea was similar, but that of E. tetralix was considerably lower. (3) Erica cinerea and E. tetralix showed a marked increase in carbohydrate concentration over winter, whilst any increase in that in Calluna was slight. (4) The between-site variation of carbohydrate concentration in Calluna, and to some extent in Erica tetralix, was correlated with the latitude and altitude of origin of the material. (5) The pronounced winter increase and the lack of variation in carbohydrate concentration among Erica cinerea and E. tetralix of different provenance may restrict these species to oceanic climates with mild winters, where temperatures would allow continued physiological activity and carbohydrate accumulation. The greater variation observed among Calluna of different provenance may reflect its adaptation to a wider geographical range.