Determining the Effect of Low Gamma Radiation and Methyl Jasmonate on the Regeneration of Vanilla planifolia

This chapter highlight the effect of low dosage of gamma radiation and methyl jasmonate on the regeneration of Vanilla planifolia, a tropical climbing orchid from the family Orchidaceae. Somaclonal variations obtained by in vitro mutagenesis with gamma radiation are free of regulatory constraints and allow the regeneration of genetic variations in a short period of time at low cost, added to which this system provides easy manipulation of explants in confined and controlled spaces under aseptic conditions. V. planifolia plant was surface sterilized before inoculated on Murashige and Skoog medium and incubated for three weeks at 25±2ºC. After incubation, the cultures were exposed to three doses of gamma radiation (0 Gy, 10 Gy, 20 Gy and 30 Gy). Then, the cultures were directly transferred into five different concentration of methyl jasmonate (0 µM, 10 µM, 20 µM, 40 µM and 80 µM). After ten weeks, the result showed that regeneration of V.planifolia was highest at 20 µM methyl jasmonate media after exposed to 10 Gy irradiation, where shoot height was 14.5±0.4 cm. Internal metabolism in plant depend highly on photosynthesis because photosynthesis is the fundamental source of energy for growth and development. The number of leaf, root length and root number also showed the highest for 10 Gy cultures in 20 µM methyl jasmonate while the lowest regeneration was collectively obtained from 80 µM methyl jasmonate. However, no morphological changes were detected in all treatments. Gamma irradiation and methyl jasmonate have a high potential for boosting vanilla culture regeneration. However, only low dose gamma irradiation and methyl jasmonate concentration resulted in a beneficial outcome, whereas high dose and concentration resulted in a negative outcome.