ÃÞ »¨ ѧ ±¨ Cotton Science 2009£¬21(2)£º144-152
PMC- FISHs in Hybrids of Tetraploid Cultivated and Diploid Wild Gossypium Species Abstract£ºPMC-FISH (pollen mother cell-fluorescence in situ hybridization) technology was firstly applied to identify probed chromosomes in univalent, bivalent and multivalent, as well as to distinguish star- or fragment-like hybridization signals from non-probed chromosomes in four triploid F1 hybrids produced by cultivated allotetraploid cotton crossed with different diploid cotton species in the genus Gossypium . Using genomic DNA from A genome species as probe, the meiotic chromosome configurations in metaphase ¢ñ of four triploid F1 hybrids were identified as 1 ¢ó aad + 1 ¢ò aa + 4 ¢ò ad + 7 ¢ò dd + 5 ¢ñ a + 7 ¢ñ d for (AD)1D5( G. hirsutum¡ÁG.raimondii ), 1¢õ aaaad +1 ¢ó add + 2 ¢ò ad + 8 ¢ò dd + 6 ¢ñ a + 5 ¢ñ d for (AD)2D4( G. barbadense ¡Á G. aridum ), 2 ¢ó add (adc or acc) + 1 ¢ò aa + 9 ¢ñ a + 4 ¢ò cc (dc or dd) + 14 ¢ñ d (c) for (AD)1C3 ( G. hirsutum¡ÁG. australe ), and 1 ¢ò aa + 1 ¢ò ad (ac)+ 10 ¢ñ a + 6 ¢ò cc (dc or dd) + 13 ¢ñ d (c) for (AD)1C1-n ( G. hirsutum¡ÁG. nandewarense ), respectively. While the two cultivated tetraploid species, G. hirsutum (AD)1 and G. barbadense (AD)2 , which were used for the triploid female parents, displayed the same chromosome configuration as 13 ¢ò aa + 13 ¢ò dd. It is obvious that there were more bivalents but less univalents in ADD £Û(AD)1D5 and (AD)2D4£Ýtype than that in ADC(AD)1C3 and (AD)1C1-n£Ýtype of triploid F1 hybrids and with fewer A-subgenome univalents and more A-subgenome combined pairings in ADD than in ADC type of triploid F1 hybrids. The results indicated that specific relationship of AD cultivated tetraploid species with D genome may be much closer than with C genome, and that the PMC-FISH technology may play an irreplaceable role in the specific relationship analyses of triploid F1 hybrids in Gossypium.
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