Anatomical and hnctional differences and nyctinastic leaf movements in Chenopodium album L. and Chenopodium hircinum Schrad. (Chenopodiaceae)

The anatomical structure of the leaves of Chenopodium album L. and Chenopodium hircinum Schrad. has been examined. Leaf chlorophyll content (Chl), specific leaf area (SLA), specific leaf weight (SLA^-1) and nitrogen content (N₂) were estimated in both species. Ch1, SLA and N₂ were greater in C. album than in C. hircinum. SLA^-1 data showed that C. album is more efficient than C. hircinum , because the former invests smaller quantities of dry weight to achieve a square centimetre of leaf area. The possible effects of Chl, N₂ and leaf anatomy on efficient gas exchange are discussed. The presence of nyctinastic leaf nocturnal movements was detected in both species. The meaning of this is discussed in relation to the prevention of the loss of pollen grains.