Somchai Chuan-udom, Witool Chaipakdee, and Rerm-a-run Rugpheug

pp. 561 - 568

Abstract

In order to get rid of contamination from Agrobacterium tumefaciens, the bacterium employed in
gene transformation, various kinds and concentrations of antibiotics were added singly or in combinations.
In this investigation, concentrations of cefotaxime and kanamycin were examined for callus formation
and regenerability from leaves and callus. The results showed that cefotaxime at the concentration of up to
300 mg/l gave a non-significant difference in callus formation. In the case of direct shoot bud formation, concentration over 100 mg/l drastically reduced percentage of leaf-forming shoot buds. The calli which
were cultured continuously in 300 mg/l cefotaxime-containing medium for 6 passages gave callus forming
shoot buds of 35%. Higher concentration of cefotaxime drastically decreased bud formation. In the case
of kanamycin, callus could be induced and maintained in the medium supplemented with a lower concentration than cefotaxime. However, the callus could not be maintained after 3 subculturings.