Molecular Markers Of Resistance Gene And The Identification Of Physiological Races Of Powdery Mildew On Xinjiang Muskmelon

This test identies physiological races of powdery mildew on Melon,uded collection1(powdery mildew that resist varieties) and queen (feeling powdery mildew varieties) and its F2segregating population as materials, the237single plants of F2populations were inoculated and identified disease of resistance in the young time,use the DNA of extremely resistant strainsion and tremendous strains of F2populations to establish pool, with Bulked separate groups group (BSA) mixed analysis by SSR, SRAP markers,looking for the mark chain with resistance genes, the main results are follows:1. used the methods of eyebrow needle taking a single spore of powdery mildew and the vitro body round leaves cultivation, differentiate hosts with the introduction of international general physiological races of powdery mildew on melon,and initially confirmed that powdery mildew from sanya in HaiNan research base of shed is physiological races1of single shell powder capsule bacteria (Sphaerotheca fuliginea) kind; the method of using the vitro body leaves is feasible to save powdery mildew, and the fresh spores, but the saving cycle is short, we need to inoculate constantly in a new leaf; contrast Directed inoculation on dry spores powder and spray method, the spray method appeared severity and early.2. F2population characters searated,and appeared resistant and susceptible plants.Identify237strains of the F2populations by Field identification,174plants resist disease,63strains susceptible disease. The survey showed that F2population of resistant and susceptible to separation is in the ratio of3:1, thus concluded, resistance of powdery mildew of the survey Field is control by a single dominant gene.3. In the SRAP stability studies, after expansion optimization, the best reaction conditions SRAP for:20μL system template DNA36ng, Taq DNA polymerases2.5U, dNTPs2.25mmol/L, primer0.6U mol/L and Mg2+1.75mmol/L,2μL10×PCR buffer; Response program:95℃the degeneration5min,95℃degeneration1min,35℃annealing1min,72℃extensions1min, five cycle;95℃degeneration1min,51℃annealing1min,35circulation;72℃extensions10min;4℃preservation.4. With BSA (Bulked segregant analysis) method, using resistant disease gene pool and susceptible gene pool filtrated SSR,SRAP markers of disease resistance gene. The results showed that the primer P173-174in F2generation parents and resistance to feeling between gene pool expansion out about a size of200bp polymorphism band, primer Me4+Em37between parents and F2generation in resistance and susceptible gene pool expansion out a size of about150bp of polymorphism band. In the F2generation group to test yield, P173-174and Me4+Em37were given187and article180of the bands of polymorphism. Based on the linkage analysis by JoinMap4.0, the linkage distance between SSR, SRAP two markers and powdery mildew resistance gene were28.3cM and19cM, respectively.