Rapid Propagation Of Glycyrrhiza Uralensis Fisch And Genetic Analysis Of Regenerated Plantlets

Glycyrrhiza uralensis Fisch.is a kind of famous Chinese traditional drug.The wild resources of liquorice are becoming less and less.So the artificial planting is being inevitable.The intent of this study was to establish the tissue culture system of the liquorice and evaluate the genetic stability for regenerated plants.The main results were as follows:Natural seeds of liquorice were taken as testing material in this study.Some factors,which influenced the germination of liquorice seed,such as the sterilizing time,the treatment of hormone and the culture temperature were studied.The best condition for the germination of the liquorice seed was as follows:the seeds of liquorice were soaked in mercuric chloride solution of 0.1%for 8min,the most suitable culture medium was MS+6-BA1.0 mg/L+IBA 0.2 mg/L,and the best culture temperature was 25 to 30?.The ratio of germination was 80%.In the tissue culture system,the shoot of liquorice was cultured on the medium MS+6-BA 1 mg/L+IBA 0.25 mg/L+sucrose 30 g/L.After 4 weeks,the proliferation rate was 5.6.In the culture medium as MS+NAA 0.5 mg/L+2,4-D 0.5 mg/L+6-BA 0.5mg/L+sucrose 30 g/L,the hypocotyl was the best among different explants with its inducing ratio reached 100%.The callus inducing in the culture medium as MS+6-BA 0.5mg/L+NAA 0.05 mg/L+TDZ 0.5 mg/L+sucrose 30 g/L.4 weeks later,the differentiation rate reached 28%.The plantlets were induced to root in the culture 1/2MS+KH₂PO₄13.5mg/L+IBA 0.5 mg/L.After 4 weeks,rooting proportion was 98%.The optimal transplanting medium was as follows:turfy soil:pearlite:vermiculite=1:1:1.74%of survival rate can be achieved.Comprehensively compared,the way of inducing plexiform stems from new shoots is the best scheme of tissue culture in liquorice.Subcultures of liquorice plantlets were test by using morphological observation,cytology test and SRAP markers.According to the morphological observation,the plant type,leaf shape and color and other aspects of the plantlets were normal.The ploidy of chromosomes was identified with flow cytometry,and the result showed the ploidy was same as the primary plant,namely diploid.Chromosome observation showed that the basic chromosome number of liquorice was 2n=2x=16.At the molecular level,the SRAP profiles showed that there were no differences with tissue culture plantlets.Above all,tissue culture plantlets through inducing plexiform stems can keep stability for genetics to some extent.