Study On Genetic Diversity And Rapid Propagation Of Medicago Falcata L. Lines

Medicago falcata L. is a most important forage species. This paper taking 4 lines (A, B, C, D) and 5 germplasms( E, F, G, H, I )of Medicago falcata L. as materials, use SDS-polyacrylamide gel electrophoresis for the seed storage protein research techno- logy, analysized the genetic diversity, and their inter-relationship. Then, using cotyle- don and hypocotyl of three lines (A, B, C) of Medicago falcata L. as explant, analysi- zed the effect of different medium on callus induction, differentiation and rooting. Using young stem as explant, analysized the effect of different medium on subculture, proliferation and rooting. Also using stem of line D analysized the effect of different plant growth regulator on rooting. The results were as follows:(1) Using SDS-polyacrylamide gel electrophoresis for the individual sampling method, that detected a total of 69 bands and 56 bands were polymorphic and polym- orphism amounted to 81.16%. This showed that: there were plenty genetic diversity at protein level of 4 lines A, B, C, D and 5 germplasm E, F, G, H, I of Medicago falcata L. , which the germplasm H has the most abundant genetic diversity, and the second is germplasm F. The other order were: A> E> D> C> B> I> G.(2) The 9 test materials for the total genetic diversity is 0.2214, genetic differe- ntiation factor (Gst) to 0.4929 <0.51, 49.29 percent of the genetic variation found int- er the tested materials and 50.71% exists in the tested materials. Showed that inter the tested materials have a high degree of variability and greater genetic differentiation.(3) Based on the Nei's genetic distance of different lines and related germp- lasm using UPGMA method to clustered. restults showed that nine of the tested mat- erials to fall into four categories, first D as a separate category, second germplasm H and I as a category, third lines C as a separate category , Finally lines A ,Band germ- plasm E, G, F as a cagegory.(4) Using the groups of smapling methods detected a total of 58 bands, which have 38 common bands and 20 bands show polymorphism, and polymorphism amou- nted to 34.48%, it is bellow the individual sampling method. (5) Through the comparative study of various medium, Selected the feasible medium of lines A and B: The callus inducing medium: SH+2,4-D2.0mg/L+6-BA 0.5mg/L; Differentiation medium: SM+KT0.3 mg/L+NAA0.2 mg/L+CH250 mg/L; The rooting medium: MS medium. The propagation coefficient are 12.9 and 10.40 respectively.The feasible medium of lines C: The callus inducing medium: SH+ 2,4-D2.0mg/L+6-BA0.5mg/L; Differentiation medium: SM+KT0.15mg/L+NAA 0.25 mg/L; The rooting medium: MS medium. The propagation coefficient is 12.65. The feasible medium of lines D: The subculture, proliferation and rooting medium: SH+NAA0.2mg/L. The propagation coefficient is 6.35.(6) Through different plant growth regulator of cuttings rooting of cuttings res- earch,The results showed: the greatest impact is use 6-BA 30mg/L treat on cuttings, the survival rate is 91%, No of rooting is 5, the length of rate is 7.12cm.