Summary
Cassava clones traditionally cultivated in Africa, frequentty show some degenerating signs ("African Cassava mosaic"). Refering to an healthy clone from VietNam, the distribution, transmission and progression of the causal agent have been observed from cutting and graft experiments. In vitro culture enable us to adjust thermotherapy treatments leading to the cure of all the studied clones and to obtain an accelarated vegetative multiplication leading to the rapid reconstitution of healthy clones.