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In vitro culture initiation and multiplication<br />

Another experiment was conducted with R. sabulosa shoots to investigate the effect<br />

<strong>of</strong> other cytokinins and different concentrations <strong>of</strong> kinetin on shoot multiplication. R.<br />

sabulosa shoots initiated and multiplied with 23.2 M kinetin were placed in 250 ml<br />

jars containing 30 ml MS media supplemented with no plant growth regulators<br />

(control) or 2.5, 5.0, 7.5 M kinetin, BA, mT, mTR or MemTR. For each treatment, 5<br />

replicate bottles with 4 explants each were used. After 2 months the number <strong>of</strong><br />

shoots formed was recorded.<br />

5.2.5 Statistical analysis<br />

Data were analyzed for significant differences by one-way analysis <strong>of</strong> variance<br />

(ANOVA), and means separated using either Tukey’s HSD test or Duncan’s multiple<br />

range test (DMRT) at 5% level <strong>of</strong> significance (P 0.05). Percentage data were<br />

converted to proportion, arcsine transformed and then analyzed. GenStat ® (VSN<br />

International, Hemel Hempstead, U.K.) version 11.1 statistical package was used to<br />

analyze the data.<br />

5.3 RESULTS<br />

5.3.1 Explants from seedlings<br />

In the preliminary experiment with R. diversiformis, R. flava, R. leipoldtii and R.<br />

minutiflora, no shoots developed from root and shoot explants and shoots only<br />

developed from seedling hypocotyls (Results not shown due to low replication).<br />

Hypocotyls <strong>of</strong> R. leipoldtii placed on a medium supplemented with 22.2 µM BA<br />

developed the largest number <strong>of</strong> shoots. R. flava seedling hypocotyls produced less<br />

shoots per explant than those <strong>of</strong> R. leipoldtii on the same medium. R. minutiflora<br />

hypocotyls only formed shoots when placed on a medium supplemented with 23.2<br />

µM kinetin and 5.4 µM NAA. R. diversiformis hypocotyls formed no shoots and only<br />

developed abnormal root-like structures. The shoots <strong>of</strong> R. leipoldtii appeared vitrified<br />

and when 50 shoots, multiplied on a medium supplemented with 23.2 µM kinetin,<br />

were placed in 33 ml culture tubes with 10 ml <strong>of</strong> MS media with no plant growth<br />

regulators, no rooting was observed after 2 months.<br />

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