Effect of plant growth regulators on the growth of Orychophragmus violaceus plantlets in vitro

Orychophragmus violaceus (L.) O.E.Schulz, which belongs to Orychophragmus Bunge (Cruciferae), is an annual or biennial wild plant. Much attention has been paid to it from researchers for its adaptability to karst and great economic worth and medical value including anticancer role (contaning anticancer substance glucoraphanin in seeds) [1,2]. High efficient propagation is necessary for mass production of Orychophragmus violaceus. The successive information of plantlets in vitro was obtained via using image analysis technique. The effect of plant growth regulators on the growth of Orychophragmus violaceus plantlet in vitro was studied. Nine treatments with different additions of 6-benzyl aminopurine (6-BA) and naphthalene acetic (NAA) supplemented to MS medium were carried out. The biomass of plantlets in vitro in sterilized condition was acquired via image analysis technique. There is a significant correlation between the biomass obtained from the image analysis and those from the manual measurement (Y=0.9497X + 0.0018, R²=0.9861, n=29, P<0.01). The difference of effect on the growth rates by various growth regulators assembly is significant. The high level of 6-BA and NAA is disadvantageous for the growth of Orychophragmus violaceus plantlet in vitro. MS medium supplemented with 0.02mg l^-1 NAA and 2.00 6-BA was the optimal for the growth of Orychophragmus violaceus plantlets in vitro.

Acknowledgement: The authors gratefully acknowledge the financial support from National Basic Research Program of China (973 Program) (No. 2006CB403206).

References: 1. Wu YY (1997) Comprehensive studies on plant of adaptability to karst-Orychophragmus violaceus. Guizhou Sci. Publ. House. Guiyang.

2.Wu YY et al. (2004) The studies on Orychophragmus violaceus' adaptability to karst. Guizhou Sci. Publ. House. Guiyang.