engleski

Specificities in the structure of the stomata of three different oak tree species (Quercus robur L., Quercus frainetto Ten. and Quercus cerris L.)related to the influence of ecological factors

The results of stomata investigtions of three different oak tree species (Quercus robur L., Quercus frainetto Ten. and Quercus cerris L.)in relation to the influence of ecological factors are presented. Positions of stomata on the leaf surface and its reverse related to the epidermis level have been studied. At the same time type of stomatal apparatus and average number of stomata on the leaves of the plants differing in age, position of the leaf on the branch, leaf region and the habitat of the plant have been examined. In all plants examined stomata are situated in the lower epidermis. They are always convehed above the epidermal level. Cells of the stomata are of renniform or longitudinal renniform shape. Similar to the representatives of the family Gramineae, middle parts of their cell walls are thickened. Between them spindle-like spaces can be seen. From the outer side they are surrounded with 4-9 cells having wavy cell walls. Stomata surrounded with five cells are the most abundant. By their characteristics they belong to genteloguboviding type. By their size and the shape of the guard cells they are of anomocytic type, and by their wavy cell walls they are of distorted type. Both ganteloguboviding and anomocytic types are hereditary properties. Distorted type is to a certain degree variable and its apperance depends on the habitat, positio of the leaf in phytocenological structure and environmental factors.

Quercus robur L.; Quercus frainetto Ten.; Quercus cerris L.

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