Chiang Mai Journal of Science

 Catharanthus roseus (L.) also known as Madagascar periwinkle is a valuable ornamental and medicinal plant mostly due to possessing two pharmaceutical important anticancer compounds; vincristine and vinblastine. Successful and efficient methods for seed surface sterilization and in vitro seed germination of C. roseus have been established in this study. Our analysis indicated that the effect of the sterilizing treatments were significant (p ≤ 0.05) for all the germination parameters assessed, namely: NDFG (number of days of first germination), GP (germination percentage), MGT (mean germination time), GR (germination rate) and CP (contamination percentage). The maximum GP (94.66%) was observed in sterilized distilled water for 20 min as control whereas the lower GP (2.66%) was observed in the 0.3% mercuric chloride treatment. For the surface sterilization treatments, we observed the highest percentage of contamination (94.66% CP) in control seeds whereas the lower CP was achieved by 5% Sodium Hypochlorite for 10 min and 0.3% mercuric chloride for 6 min (14.66%, 13.33%, respectively). In addition, the effect of concentration of minerals and sugars of germination medium (sucrose and glucose) were significant (p ≤ 0.05) for MGT, GR, GP, and NDFG. The maximum GP (74.66%) were achieved by mineral water medium while the minimum (48.0%) was observed in MS agar medium with 3% sucrose. The maximum length of shoot and root of in vitro developed seedlings was achieved with the mineral water treatment. According to our results, we established the best sterilization method (3% Sodium Hypochlorite for 5 min) and germination medium (mineral water, using paper boat method) for in vitro seed germination and seedling development in C. roseus.