Micropropagation of selected cassava ( Manihot esculenta Crantz) varieties through meristem culture

Abstract

Cassava, ( Manihot esculenta Crantz) is a perennial woody herb which is cultivated in sub-Saharan Africa, Latin America and Asia for its edible starchy roots and its ability to withstand marginal environmental conditions. Due to high seed dormancy and sluggish germination rate, farmers normally practice propagation of cassava by stem cuttings which have led to accumulation of viral and bacterial diseases that reduce productivity and causes loss of superior genotypes. To develop a protocol for rapid in vitro micropropagation, two cassava varieties (‘Qulle’ and ‘Kello’) were selected. Solid MS medium supplemented with different hormonal combinations was used for shoot induction, shoot multiplication and rooting. Among different treatments used for shoot multiplication, 0.5 mg/l BAP in combination with 1 mg/l GA 3 and 0.01 mg/l NAA was found to be the best; with a mean number of 12.23 and 7.22 shoots per explant for cultivars ‘Qulle’ and ‘Kello’, respectively. Root induction potential of the two varieties increased by supplementing the medium with 1mg/l of IBA. Of those shoots which were acclimatized in the greenhouse, 89.1% of ‘Qulle’ and 75% of ‘Kello’ survived. The protocol could be used for the multiplication of cassava for large-scale production. Keywords/phrases: Manihot esculenta , Meristem, Micropropagation, Tissue culture Ethiop. J. Biol. Sci ., 9(2): 127-142, 2010