Rubber tree (Hevea brasiliensis Müll. Arg.) is a tropical
perennial tree species which produces the polymer cis-
1,4-polyisoprene, widely used in industries, known as
natural rubber (Dall’Antonia et al. 2006; Obianga et al.
2009). The molecules of this polymer are produced,
aggregated, and packaged in the latex vessels (laticifers)
of rubber trees (Li et al. 2010). Latex, a cytoplasmic
component of the laticifers, is a colloidal suspension that
contains from 25% to 50% dry matter, from which 90%
is rubber (Priyadarshan 2011). Laticifers form a network
of anastomosed latex vessels arranged in concentric
circles in the trunk of rubber trees (Kongsawadworakul
& Chrestin 2003).
Latex extraction is carried out by tapping rubber
trees, defined as a process of controlled wounding and
removal of thin shavings of trunk bark to induce the flow
of latex. Since this procedure leads to the loss of plant
metabolites, it is important to interrupt the flow after a
certain time to prevent excessive loss and entry of
pathogens (Priyadarshan 2011). After tapping, this flow
stops as a result of a complex phenomenon, which
causes coagulation of latex particles and, consequently,
obstruction of the laticifers in the area of the tapping cut.
However, the progressive obstruction of laticifers gradually
reduces the amount of latex exuded and, therefore,
becomes an important limiting factor of rubber yield
(Priyadarshan 2011).