Population Division Of Melampsora Larici-Populina And Scar Markers

Melampsora larici-populina Kleb. is the important pathogen occurred in the Sect.Tacamachacae, Sect. Aigerios and their hybrids poplars in the worldwide. There has distinguished pathogenic division found within species , and the genetic background is complex. 5 races were reported in European and North America. To understand the occurrence condition and the genetic background of the pathogen in China, this dissertation focused on studying the rust fungus by pathogenesis measure, ITS sequence analysis, RFLP, RAPD, RAMs, SCAR markers and nucleates DAPI dying, and achieved results bellowing:1. Pathogenicity division study is done by inoculation M. larici-populina with poplar saplings, and the identification system of race division is founded, which includes host poplar ranges, propagation host (Poplus purdomii) and technology standards. 5 races are reported in China firstly.2. Based on compare and analysis, a rapid and minimum DNA extraction technology is established, and the optimization study of PCR operation is done. 6-fold diluted extraction liquid DNA can be used for ITS-PCR operation, and 16×-32×is the optimism dilution multiples for random primer PCR, the parameters is benefit for DNA reservation and high usage efficiency. By this DNA extraction method, the extracting operating time can be reduced into 30 min with fewer than 10㎎ urediospores,even with a single mono-uredinium and the DNA production rate can be about 882μg/g. With the Basidiomycetes specified primers designed by Gardes and Bruns in 1993, ITS of M. larici-populina happened on symptom or no symptom poplar leaves can be amplified specifically, which is important for future quarantine and polygenetic study of Melampsora spp fungi occurred in Salicaceae trees.3. Genetic division based on 11 isolates of 5 Races, which are collected in throughout China, is studied preliminarily by ITS sequence, ITS-RFLP,RAPD and RAMs molecular technologies. The results indicate the genetic division is correlated to the originate locus of isolations. The tested isolations can be separated into Northern geographic population and Western geographic population, and the latter can be separated into Hi-mountain forest ecologic type and western plain ecologic type. Genetic division must not correspondent with the race's pathogenic.The same genentic background isolates may belong to the different races. T test shows the genetic index of Race C2 is significantly different to the Race C4,C3,C1,no...