Genetic Relationship Of Picea Mongolica And Its Relative Species Based On Genomic In Situ Hybridization

Using genomic in situ hybridization(GISH),make Picea meyeri genomic DNA as probe Picea koraiensis genomic DNA as blockade and make Picea koraiensis genomic DNA as probe Picea meyeri genomic DNA as blockade,Identification of metaphase chromosomes of Picea mongolica genomic DNA by genomic in situ hybridization,Analysis to genetic relationship of the among of genome of three species Picea,and karyotype analysis was performed,meanwhile the experimental technique was optimized.Results show:1.Metaphase chromosomes cells of Sampling in the morning 9:00?10:00 more than in the afternoon 2:00?3:00,It may be related to cell division;The root tip was treated 6.5h with 0.1%colchicine and 1%,two methyl sulfoxide mixture under the 23 ? and 115rpm dark condition at the shaking table,there were more cells in metaphase;Under the 37? use 2%cellulase and 1%pectinase mixture Enzymatic hydrolysis 70min,the effect of chromosome dispersion is better;The method of preparing probe DNA and blocking DNA is Autoclaving 3min and the length of genomic DNA fragments is between 200 and 500bp,the best fragment size for DNA of probe DNA and blocking DNA in Spruce plant in situ hybridization.2.The genomic DNA of Picea meyeri was have hybridization signal in 14 bar chromosomes of Picea mongolica,respectively 1,2,3,4,5,6,7,8,9,10,13,14,19 and chromosome 20;The genomic DNA of Picea koraiensis was have hybridization signal in 12 bar chromosomes of Picea mongolica,is 3,4,7,8,11,12,13,14,15,16,23and chromosome 24;There are significant differences between the signal patterns;The strong signal of Picea meyeri is located in the region of the centromere or chromosome long and short arm;The signal of Picea koraiensis was located in the long arm and minority short arms.The karyotype form?la of Picea meyeri:2n=24=22m(6sat)+2sm;The karyotype formula of Picea koraiensis 2n=24=20m(4sat)+4sm;The karyotype form?la of Picea mongolica 2n=24=22m(6sat)+2sm;The most of types of the three Picea chromosome are submedian centromere chromosomes,Karyotype was 1A type;The karyotype of Picea mongolica and Picea meyeri was identical.Explain,the genetic relationship of Picea meyeri and Picea mongolica is more closer than Picea koraiensis,Base on the GISH signal distribution of genomic DNA of Picea meyeri and Picea koraiensis,was analysis to Chromosome karyotype of Picea mongolica,show that the hybridization signal intensity and distribution of Picea koraiensis was significantly lower than of Picea meyeri.this again shows that Picea mongolica and Picea meyeri genetic relationship nearer.Above findings it provides technical support and theoretical basis for molecular cytogenetics research of gymnosperms.