ultimately,
total stoppage of
latex flow upon tapping,
due to in situ coagulation of
rubber particles.
Numerous
studies
have shown that TPD
appears to be
a physiological disorder resulting from excessive recurrent tapping and overstimulation by ethylene [6,7,8,10,11]. The term TPD is related to two types of physiological symptoms. Firstly, a temporary halt in latex flow is reversible after a resting period for the trees (Figure 1d–f) [8]. This form of TPD is related to an overproduction of reactive oxygen species (ROS) in laticifers, called ROS-TPD in this manuscript. In aggravated conditions, an irreversible-type of TPD occurs that is called brown bast TPD (BB-TPD) (Figure 1g–i). The latter involves histological deformation of bark due to thylosoid formation, lignified gum, and abnormal division of parenchyma cells, and may be related to a cyanogenesis process