Study On Radiation Effect Of ⁶⁰Co-? Rays On Callus Of Panax Ginseng C.A.Mey

Ginseng?Panax ginseng C.A.Mey?,a kind of perennial herbaceous medicinal plant from Panax,araliaceae,is an essential medicine for reinforcing qi,and is widely used for the prevention and treatment of various diseases.Though ginseng has wide distribution and sufficient planting area,having few number of varieties,long growing periods and strict requirements of the growing environment have made it hotpot researching on breeding method enrichment and more germplasm creation during ginseng breeding.In this study,the callus of ginseng was mutagenized through being irradiated by⁶⁰Co-?rays.The radiation intensity of 19.38Gy,35.98Gy,60.9Gy,83.04Gy,and112.1Gy were applicated.The mutagenic effect caused by radiation on ginseng callus was explored by inspecting the morphological parameters,physiological properties,cytology changes and genetic stability of ginseng callus after radiation,along with semi-lethal dose being screened out,The main results are as follows:1.After ginseng callus was irradiated by ⁶⁰Co-?rays,with the increasing of radiation dose and the extension of recovery culturing time,the degree of suppression on callus growth was gradually up,the browning rate increased,the water loss was severe and the rate of increment reduced.A linear analysis was used to determine that the semi-lethal dose of radiation to ginseng was 40 Gy.2.After radiated by ⁶⁰Co-?rays,the content of MDA in ginseng callus increased with the rising of radiation dose,and decreased with the extension of recovery culturing time.The activity of SOD increased with the rising of radiation dose,and increased first then decreased with the extension of recovery culturing time.After the decrease,the CAT activity and POD activity increased first then decreased and rose again with the increasing radiation dose.The CAT activity increased with the extending recovery culturing time,while the POD activity decreased first and then increased with the extension of the recovery culturing time.The soluble protein concentration increased first and then decreased with the rising radiation dose and prolongation of recovery culturing time.The content of soluble sugar increased first and then decreased with the rising radiation dose while decreased first and then increased with the extension of recovery culturing time.3.After ginseng callus was irradiated by ⁶⁰Co-?rays,as radiation dose increased,the nucleolar staining became lighter,the cytoplasm shrank,the nuclei were gradually degraded,the organelles were broken,and serious plasmolysis was discovered.What's more,the number of chromosomes in the cells was mutated and an aneuploidy occurred;the number of mitochondria decreased and spread to the cell membrane,and the structure expanded.4.After ginseng callus was irradiated by ⁶⁰Co-?rays,18 ginseng SSR core primers were used to amplify the bands in the control group and the radiation group,among which the primers of P35 and gm129 amplified specific bands.Compared with the control group,a band loss phenomenon was found.5.After ginseng callus was irradiated by ⁶⁰Co-?rays,HPLC-MS/MS method was used to inspect ginsenosides.The content of M-Rb1,M-Rc/Rb2/Rb3 and M-Rd in35.98 Gy dose dealing,M-Re,Rb1,Re,Rf,Rg2 in 83.04 Gy dose dealing,Rc,M-Rd in 19.38 Gy dose dealing,were all discovered to be higher than those in control group.