Beneficial effect of arbuscular mycorrhizas on acclimatization of micropropagated cassava plantlets

Survival and development of cassava (Munihot esculentu Crantz)plantlets has been increased by modifying tissue culture protocols and by mycorrhizal inoculation. About 90 percent of plantlets were successfully rooted in vitro and 75 percent survived after the acclimatization phase. Inoculation with Glomus deserticola early in the post vitro weaning stage enhanced percent survival and improved tolerance to the transplanting stress. Shoot, root and tuber development of the micropropagated plants was increased following inoculation with different arbuscular mycorrhizal (AM)fungi. Growth responses were dependent on both the cultivar (clone)and the AM fungi involved. G. deserticola was very effective in improving growth of both clones, the effectivity of G. clarum and G. fasciculatum being dependent on the cultivar. These results emphasize the need for selection trials before appropriate plant cultivar/AM fungi combinations can be recommended.