A Study on Foliar Epidermis in Betulaceae

Chen Zhi-Duan, Zhang Zhi-Yun

Received:1900-01-01 Revised:1900-01-01 Online:1991-03-10 Published:1991-03-10
Contact: Chen Zhi-Duan

Abstract:

Light and scanning electron microscopes were used to examine foliar epidermal

features such as the shape of epidermal cells, the type of stomatal apparatus and outer

stomatal rim in 38 species of 6 genera of the Betulaceae. Four types of stomatal apparatus on

mature leaves are recognized in this survey: anomocytic, cyclocytic, non-typical actinocytic

and brachyparacytic. The foliar epidermal characters and character states are taxonomically

useful for the identification of genera and the division of tribes.

The generalized evolutionary scheme for foliar epidermal features is fairly closely corre-

lated with the generic relationships proposed in other studies (Abbe, 1935, 1974; Brunner &

Fairbrothers, 1979; Hall, 1952; Kikuzava, 1982; Kuprianova, 1963)and it is clear that foliar

epidermal morphology can be an important taxonomic character added to others for deter-

mining evolutionary relationships. The explanations of generic relationships are based on

our hypothesis that anomocytic stomatal apparatus, uni-layered outer stomatal rim, having

not T-pieces at the polar region of guard cells and straight anticlinal wall of lower epidermal

cell are from the ancestor (Fig. 1). Sinuolate or sinuate anticlinal wall of lower epidermal

cells and non-typical actinocytic stomatal apparatus, present in Corylus, Ostryopsis, Ostrya

and Carpinus of the Betulaceae, correlates with the separation of Coryleae from

Betuleae. Betuleae including Alnus and Betula is considered primitive with more primitive

characters. Of Coryleae, Carpinus might be the most advanced, with brachyparacytic

stomatal apparatus and double-layered outer stomatal rim.

Key words: Betulaceae, stomatal apparatus, Foliar surface features

Chen Zhi-Duan, Zhang Zhi-Yun. A Study on Foliar Epidermis in Betulaceae[J]. .

[1]	Chen Zhi-duan. Phylogeny and Phytogeography of the Betulaceae (to be continued) [J]. , 1994, 32(1): 1-31.
[2]	Chen Zhi-Duan. Pollen Morphology of the Betulaceae [J]. , 1991, 29(6): 494-503.
[3]	Pan Kai-Yu, Lu An-Ming, Wen Jie. Characters of Leaf Epidermis in Hamamelidaceae (s. l.) [J]. , 1990, 28(1): 10-26.

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