Banana is an important fruit crop of the Musaceae family, widely grown in developing countries. Nowadays Musa spp. are propagated vegetatively. Conventional micropropagation techniques can inefficient for commercial purposes. Bananas are e.g. vegetatively propagated by using corms, suckers, and sword suckers. These materials can harbor pathogens, such as fungi, nematodes, viruses, and insects. Micropropagation allows a rapidly and efficiently method to obtain high multiplication rates and disease-free plant material.
Several methods have been tested for micropropagation of banana, which strongly different in their results and production capacity and practicability. Regeneration of somatic embryos from cell suspensions is for example difficult, but can lead to large plantlet amounts. A simple method is to regenerate new plants from shoot tips:
General steps for shoot tip regeneration of Banana
Several parameters are species specific and therefore not listed in full details.
- Selection of plant material
- A distinction must be made between materials derived from greenhouse field. Field-grown materials are dirtier and more contaminated at the beginning, which makes greenhouse materials more suitable for the sterilization procedure
- Suckers should be selected from healthy plant material only
- Outer layers from suckers and corm tissue has to be removed carefully
- Sterilization is performed by combination of treatments with different sterilization agents. Commonly used is ethanol, mercuric chloride and sodium hypochlorite.
- Shoot tips are isolated and cultured on an initiation medium
- After incubation and formation of shoots, the explants are transferred on a multiplication medium
- Multiplication stage
- shoot cultures increase in their size and multiply, which allows a separation of the plantlets and further subculture on multiplication media
- Rooting stage
- plantlets are transferred on a rooting medium which induces the root formation
- ex vitro transplantation requires cleaning of plantlets from culture media
- rooted plantlets need to be acclimatized in an hardening-off period
- gradually lowering humidity helps the plant to acclimatize on the new environment conditions