The structure ofAlbomargin ata andMedioalbinata forms
From both experiment and theory, our knowledge of the structure of thepseudo-medioalbinata, albomarginata, andmedioalbinata leaves may be summarised as follows:
Thepseudo-medioalbinata form is a green-over-white periclinal, modified secondarily by the influence of the albinotic endohistogen. Its progeny therefore are all green. Root cuttings may give rise to albinotic shoots.
Thealbomarginata form is a periclinal with white ectohistogen in dihistogenic plants. In these plants, the ectohistogen develops into the epidermis and the marginal mesophyll of leaves, while the endohistogen constitutes the other inner components. The white-fringed leaves of such trihistogenic dicotyledons asDaphne andFragaria are due to the development of the white ectohistogen that forms the epidermis and the fringed mesophyll of the leaves.
Themedioalbinata form, which occurs in some monocotyledons, is due to the green-over-white arrangement of the two histogens.
Volume 100, 2021
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode