Even in the present study, a synergistic combination
of NAA (5.36M) and BAP (3.80M) led to maximum
protocorm proliferation which did not differ significantly from
other treatments (2.70M IAA + 2.22M BAP, 1.35M+ 3.80M
BAP and 5.40M+ 3.80 BAP) when cultured on media with NAA
or BAP alone, which further confirms that a proper ratio of auxin
and cytokinins is required for optimal PLB multiplication.