CONTAMINATION OF PRIMARY CULTURES IN TROPICAL AREAS: THE CASE OF HEVEA BRASILIENSIS

Hevea brasiliensis is the quasi-exclusive source of natural rubber, and is the subject of several improvement programmes. In vitro micropropagation is one way to improve the homogeneity of plantations and hence productivity.
Contamination is a constant problem which can compromise development of all in vitro techniques.
It is more serious with arborescent species and still more so under tropical ecological conditions.
In humid environments such as that of Guadeloupe (FWI), it was found that fungal and bacterial contamination was very high in comparison with results of observations in a temperate climate.

It was found that a relatively small number of species of bacteria and fungi were responsible for contamination, and several method were used to reduce them to levels compatible with the use of micropropagation.
Trials were carried out on disinfectants, antimicrobial agents and on selection of explants.
It was found that the introduction of antibiotics in the medium or using them in soaking treatments together with repeated strong disinfection were not sufficiently effective.
Hence pre-conditioning of the mother plant with antimicrobial agents and use of the highest section of young stem followed by application of several disinfectants like Desogerme and alcohol and brushing, and application of NaOCl were necessary to overcome the difficulties.

Bacterial and Bacteria-like Contaminants of Plant Tissue Cultures

F. Enjalric, M.P. Carron, L. Lardet

https://doi.org/10.17660/ActaHortic.1988.225.6