Articulated laticifers The
cells (
laticifers) in which latex is found make up the laticiferous system, which can form in two very different ways. In many plants, the laticiferous system is formed from rows of cells laid down in the
meristem of the
stem or
root. The
cell walls between these cells are dissolved so that continuous tubes, called latex vessels, are formed. Since these vessels are made of many cells, they are known as
articulated laticifers. This method of formation is found in the
poppy family and in the
rubber trees (
Para rubber tree, members of the family
Euphorbiaceae, members of the
mulberry and fig family, such as the Panama rubber tree
Castilla elastica), and members of the family
Asteraceae. For instance,
Parthenium argentatum the guayule plant, is in the tribe
Heliantheae; other latex-bearing Asteraceae with articulated laticifers include members of the
Cichorieae, a
clade whose members produce latex, some of them in commercially interesting amounts. This includes
Taraxacum kok-saghyz, a species cultivated for latex production.
Non-articulated laticifers In the
milkweed and
spurge families, on the other hand, the laticiferous system is formed quite differently. Early in the development of the seedling, latex cells differentiate, and as the plant grows these latex cells grow into a branching system extending throughout the plant. In many
euphorbs, the entire structure is made from a single cell – this type of system is known as a
non-articulated laticifer, to distinguish it from the multi-cellular structures discussed above. In the mature plant, the entire laticiferous system is descended from a single cell or group of cells present in the
embryo. The laticiferous system is present in all parts of the mature plant, including roots, stems,
leaves, and sometimes the
fruits. It is particularly noticeable in the
cortical tissues. Latex is usually exuded as a white liquid, but is some cases it can be clear, yellow or red, as in
Cannabaceae. == Productive species ==