The two sweet potato varieties had significant (P <
0.05) differences in plant elongation during the second
and fourth weeks of culture with KEMB 36 having
taller plants compared to Tainurey (Fig. 4).
However, at the end of the sixth week no significant
(P > 0.05) differences were recorded in heights of
plantlets of the two sweet potato varieties. This
indicates that the variety KEMB 36 responded better
to the low cost medium compared to Tainurey. Sweet
potato has been reported to be a recalcitrant crop to
regenerate and often has genotype-dependent response
to in vitro regeneration [11]. Results showed
differences in culture efficiency of the sweet potato
varieties Jewel and CEMSA 78354. This
genotype-dependent response to regeneration methods
has made sweet potato to lack an efficient and reliable
system, which further compromises transformation
strategies. It has been reported that one of the
challenges in developing transgenic sweet potatoes is
that novel or modified in vitro regeneration procedures
must be developed for each desirable genotype
because of the significant variability in the response to
hormone combinations [12].