There are usually two methods of Gerbera tissue culture, direct and indirect macro-propagation. There is a table given for the comparison of both approaches;
| Indirect method | Direct method |
| Callusing | Without Callusing |
| Induce Variation | Avoid Variation |
| Time taking | Time effective |
| Costly | Cost-effective |
Gerbera tissue culture limitations:
- The establishment of in vitro cultures of Gerbera can be difficult because of the frequent contamination of initial explants.
- Stock solutions of plant growth regulators should be prepared separately. Ensure that MS stocks are free from contamination at the time of use.
- Media should be autoclaved properly and stored for 1 week before use, to ensure that it is free from microbial contamination.
- Use young and juvenile plant parts because older parts develop wax layers and produce phenolic compounds.
- Whenever surface fungicides fail to prevent contamination of cultures, use systemic fungicides (Carbendazim + Mancozeb). 4. Notes Fig. 5. ( a ) Four-week-old plants hardened in a potting mixture containing farm yard manure, sand, and soil (1:1:1 by volume), ( b ) Hardened plants after 6 months, ( c ) Flowering plant of Gerbera. 24 Gerbera Micropropagation 315
- The treatment time of explants with sterilizing agents should be monitored carefully. Too long or too short treatments of sterilization will result in browning or contamination of explants, respectively.
- Ethanol, sodium oxychloride, and commercial bleach are effective sterilization chemicals.
- Wash explants thoroughly during each step of surface sterilization to remove any traces of toxic sterilizing agents sticking to the explants. Gloves should be used while handling mercuric chloride solution.
- Shoot regeneration from stem apices is highly genotype-specific. The present protocol is effective for most of the local cultivars.
- Dedifferentiation from the callus is a slow process and takes 3–4 months. Subculture callus to fresh culture medium every 4 weeks.
- The best shoot regeneration from callus has been obtained with different concentrations of BA, however, the number of shoots per callus varied with the change in BA concentration.
- IBA is most effective for root induction in Gerbera.
- Remove dead or broken lateral roots before transfer to the potting mixture.
- It is recommended to cut very long roots; 3–4 cm long roots are preferred for transferring to the soil.
- Perlite, sphagnum, peat, sand, cocopeat, and farmyard manure, mixed in different ratios, are effective for ex vitro acclimatization of Gerbera.
- It is mandatory to maintain 85–90% relative humidity around the plants during the first 10–15 days of transfer to pots.
