The Induction Technique Research Of Autotetraploid Of Glycyrrhiza Uralensis Fisch.

Glycyrrhiza uralensis Fisch. is the perennial herb of the Leguminosae Glycyrrhiza Linn. The root and the rhizome of Glycyrrhiza uralensis Fisch. includes secondary metabolite such as Glycyrrhizinic acid, Glycyrrhizin et. Glycyrrhiza uralensis Fisch. has the function of reducing internal heat and detoxication, relieving cough, dispelling phlegm, nourishing the spleen and the stomach and so on . It was one kind of very important Chinese traditional medicine. The karyotype research indicated that the chromosome number of Glycyrrhiza uralensis Fisch. is 2n=16, the change of chromosome number has not be reported.In this research, the seeds and tube plants of Glycyrrhiza uralensis Fisch. were used as the experimental materials to obtain autotetraploid. The paper compared the variations of materials treatmented with CK in morphological and cytological characters, established the stem buds chromosome doubles technique system and the purification, optimized the chromosome identifiction technique system suitable for Glycyrrhiza uralensis Fisch in vitro. The pure tetraploid plants was obtained and transplanted to the field. Then characters were compared between tetroploid and CK plants. The main results were as follows:1 Micropropagation and rooting system were optimized for Glycyrrhiza uralensis Fisch. The multiplication of single stem buds could reach to 10.1 in MS+6BA1.0mg/L+NAA0.1mg/L. The rooting rate could reach to 100% in 1/2MS+ riboflavin 1.0 mg/L.2 To induce autotetraploid of Glycyrrhiza uralensis Fisch. under tissue culture condition, the stem buds soaking method was better than the seed soaking method and stem co-cultivation method. The better induction system was established as follows: precultured for 3 days, the stem buds were soaked in 0.1% colchicin solution added 1% dimethylsulfoxide for 24h, the survival rate could achieve 67% and the variation rate could achieve 33%.3 The morphological identification, isozyme identifiction and the cytological identifiction was carried separately after the induction then autotetraploid identifiction system for Glycyrrhiza uralensis Fisch plantlets in vitro was optimized, which could apply for the tetraploid examination effectively.4 By excising the single stem bud and culturing in medium, combing with the identification technique the purification system was established to obtain the pure autotetraploid of Glycyrrhiza uralemis Fisch.5 The pure autotetraploid plants of Glycyrrhiza uralensis Fisch. were obtained for the first time in the world. Those single plants with good traits were selected and be micropropagated.6 Compare with the diploid plant, the tetraploid plants growed in the field were preveliged than CK in plant height, Leaf length and width, the leaf area, the number of stem buds and branch, stem thick, root thick and so on. Statistical results showed the typical character of common polyploid plant ---huge of vegetative organ.This research created new type of tetroploid germplasm resource of Glycyrrhiza uralensis Fisch. for the first time in the world, and they could be precious materials used in further polyploidy breeding to develop new variety with high yield and high medicinal ingredient content.