Anatomical characteristics of rubber tree bark related to the production of natural rubber

Abstract

The rubber tree is a native plant from Brazil, with huge economic interest due to the production of rubber, once the produced rubber has elevated quality. A lot of importance is given to latex production, nutrition and genetic improvement of this plant. However, insufficient attention is given to the anatomic study of rubber tree bark, which is intimately linked with rubber production. The aim of this work was study the existence of relation between rubber bark anatomy and the latex production. Were selected 16 plants, four by block. The plant material was obtained by sample bark, arriving until the cambium of plant. After the collection, barks were fixed in solution of formaldehyde, acetic acid, and 70% ethanol (FAA) for 72 h and then stored in glycerinated water 1:1, for 4 days. Were realized evaluations relative to the counts of laticiferous cells and laticiferous vessels per mm2, like also the diameter of laticiferous cells, the distance between the laticiferous and the number of laticiferous vessels. The observations were realized in two blades, with 10 cuts in each one (20 cuts per plant/10 per height). The higher production of rubber was found in plants with higher number of laticiferous vessels and thickness of bark.