Study On The FISH Comparation And Origin And Evolution Of Eight Genome Species Of Gossypium

The cotton is the most important fiber economic crop in the world. It is inportant to expound cotton orgin and evolution for the cotton heredity improvement. This research carries on the fluorescence in situ hybridization compartion of cotton eight genome species to clear about interspecies relationship and the origin and the evolution of the Gossypium. The main result are as follows:1. Gsomalense has 4 singnal of 45S rDNA, Glongicalyx has 2 signal, G.bickii has 8 signal, and G.herbaceum,G.arboreum, G.anomalum, G.austral, G.trilobum and G.raimondii have 6 signal. G.arboreum have 2 strong hybridization signal located in near end of chromosome short arm obviously, the medium hybridization signals in the near end of chromosome short arm, and 2 small hybridization signals in the end of chromosome short arm. G.trilobum has 6 the signal with the same size and strength located in the end of the chromosome short arm.It is noticeable that G.raimondii has 2 major satellites, and its 45S rDNA hybridization signal is located in secondary constriction. G.longicalys and G.bickii are the special species. The 45s rDNA hybridization signals are located in the secondary constriction for the G.longicalyx,and G.bickii has 2 45S rDNA located in the end of chromosome long arm.2. G.hebaceum has major singal taking its own gDNA(genomic DNA) as probe, but G.raimondii has minor signal taking its own gDNA as probe. all of the signal are located in the near centromere regions. and the single copy genes are located in the end of the chromosome.3. There are 26 red chromosome and 26 blue chromosome with the TM-1 chromosome as target DNA, G.arboreum gDNA as probe and G.raimondii as block DNA. It implies that G.hirsutum is a allotetroploid species, and G.arboreum is the diplod progenitor of A subgenome of the G.hirsutum4. rDNA from G.hirsutum has been homogenized to a D genome repeat type.5. G.davisonii is the diplod progenitor of D subgenome of the Ghirsutum6. G.barbadense has 6 NORs(nucleolar organizing regions), the 2 NORs of them are located in the A subgenome of the chromosome of G.barbadense, and the 4 NORs are loacatend in the D subgenome. The NOR of G.barbadense comes from D genome7. G.raimondii is the the diplod progenitor of the D subgenome of the G.barbadense8. G.mustelinum has 26 red A subgenome taking G.mustelinum chromosome as target DNA, G.herbaceum.var.africanum as probe and salmon DNA as block DNA. and there are 2 major NORs located in the A subgenome without another 4 NOR. and there are 2 NORs if G.mustelinum is target DNA, G.herbaceum as probe and G.davisonii as block DNA. All of the NORs of G.mustelinum are located in the A subgenome based on the Double stained Fluorescence in situ hybridization. and all of the 45S rDNA have been homogenized to a A genome repeat type.9. G.thurberi is the the diplod progenitor of D subgenome of the G.mustelinum...