Optimization for aseptic culture of red clover (Trifolium pratense L.).

Effects for both seed disinfection methods and medium composition on tissue culture were investigated in red clover(Trifolium pratense L.).Results show that seed germination rate has no significant differences using 0.1% HgCl2,3% NaClO,or 15% H2O2 sterilization for less than 15 min.However,the efficiency of sterilization is different between the three disinfectants.The best method of seeds sterilization for red clover is the 75% ethyl alcohol treatment followed by disinfection with 0.1% HgCl2 for 10 min.Germination rate reaches 89.44% and is completely pollution-free.The most suitable medium is 1/4MS plus 1.5% sucrose without hormones at pH 6.0 for seed culture.Germination rate reached 85.78% and seedlings grew well with this medium.The content of inorganic salts in medium is one of the key factors affecting seed germination and growth in aseptic cultures.Callus induction rates of cotyledons and hypocotyl are significantly increased in agar medium as compared with filter paper,but with no significant difference among different components agar medium.