|dc.description.abstract||Shoot cultures of Aloe polyphylla were initiated from young shoot explants of in
vitro grown plants. The basal medium was MS medium (MURASHIGE and
SKOOG, 1962), supplemented with 100 mgl ¯¹ myo-inositol, and 30 gl ¯¹ sucrose.
Agar (0.8 %) was used as the gelling agent. Different cytokinins, singly or in
combination with auxins (IBA and NAA), were tested for shoot proliferation
activity. All the cytokinins tested (kinetin, zeatin, iP, and BA) gave a good shoot
proliferation response. The optimal concentrations for shoot proliferation of each
of the cytokinins tested were: zeatin (0.5 mgl ¯¹), kinetin (1.5 mgl ¯¹), iP (1.0 mg ¯¹)
and BA (1.5 mgl ¯¹). In combination with auxins, the optimal combinations were
kinetin/NAA (2.0/0.1 mgl ¯¹), kinetin/lBA (1.5/1.0 mgl ¯¹), zeatin/lBA (1.0/0.5 mgl ¯¹),
zeatin/NAA (1.0/1.0 mgl ¯¹), BA/IBA (1.0/1.0 mgl ¯¹), BA/NAA (1.5/0.1 mgl ¯¹).
Although it gave the highest number of shoots per explant, BA was responsible for hyperhydricity.
Temperature and sucrose also influenced shoot proliferation. The optimal
temperature was 25°C, while 30 gl ¯¹ was the optimal concentration of sucrose for
shoot proliferation. Plants rooted well in plant growth regulator-free MS medium.
Amongst the potting mixtures tested, soil: sand: vermiculite (1:1:1 v/v) was the best with 98 % plantlet survival.
In the second part of this project, Platycerium bifurcatum cultures were
established using leaf explants. The basal medium was MS medium
(MURASHIGE and SKOOG, 1962), supplemented with 100 mgl ¯¹ myo-inositol
and 30 g l ¯¹ sucrose. For bud initiation, 1.0 mgl ¯¹ BA was used, while 0.8 % agar
was used as the gelling agent. Three different strengths of MS medium (full, half,
and one-quarter strength) without plant growth regulators were tested for further
bud growth and development. Half-strength MS proved to be the best for further bud growth and development. Rooting was best achieved in one-quarter strength
MS medium without plant growth regulators. In vitro grown plantlets were
successfully acclimatized using peat as the potting medium.||en