Codiaeum variegatum (L.) Blume, commonly known as “croton”, is an ornamental shrub that
originates in tropical forests.
A wide range of variations in leaf shape
and coloration has fascinated breeders, landscapers, horticulturists and
gardeners, and a huge number of cultivars have been fixed for commercial production.
More than 300 cultivars are available in the ornamental horticulture industry.
Diversity in croton’s leaf-shape is
quite enormous. The leaf shapes include ovate to linear, entire to deeply lobed,
appendiculateat the middle connected by midrib. Coloration and color pattern on
the leaves is also a prominent characteristic to distinguish each cultivar.
The phenotypic diversity observed in
croton leaves is of a great interest in plant science because virtually all
types of leaf morphology can be seen in one species; the plasticity in leaf phenotype
is extremely high.
It appears that genetic instability
is associated with the leaf phenotypic diversity. Somatic mutations and/or
cross pollination by ants may be involved in the mechanism for creating such
high diversity.
A high variation in chromosome numbers
and karyotypes may attribute to the morphological diversity among the cultivars
of this species.
Croton cultivars can be devided into groups
based on leaf types:
1.
Slender
2. Oval
3. Curly
4. Lobed
5. Interrupted
Source:
Mollick A.S, et al., 2011,
Croton Codiaeum variegatum (L.) Blume cultivars characterized by leaf
phenotypic parameters, Scientia Horticulturae Volume 132, 5 December 2011,
Pages 71-79.
