View/Open - ResearchSpace - University of KwaZulu-Natal
View/Open - ResearchSpace - University of KwaZulu-Natal
View/Open - ResearchSpace - University of KwaZulu-Natal
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
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 />
121