Effect of low gamma radiation on the growth of Vanilla planifolia cultures

Abstract

A study was conducted to determine the effect of low doses of gamma radiation on the regeneration and morphological of Vanilla planifolia, a tropical climbing orchid from the family Orchidaceae. The explants were treated with seven different combinations of sterilization agents before inoculating 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 (10 Gy, 20 Gy and 30 Gy). After twelve weeks, the result showed that regeneration of V. planifolia was the highest at 10 Gy irradiation, where shoot height was 13.40±0.33 cm compared to the non-irradiated culture with only 6.89±0.21 cm. The leaf and root numbers as well as root length also showed the highest for 10 Gy cultures. The lowest regeneration was obtained from 30 Gy irradiated cultures. However, no morphological changes were detected in all treated cultures. Thus, it can be suggested that low doses of gamma irradiation stimulate the in vitro regeneration of V. planifolia.