Karyotype analysis of Gossypium arboreum x G. bickii by genome in situ hybridization.
By using genome in situ hybridization (GISH) on root somatic chromosomes of allotetraploid derived from the cross Gossypium arboreum x G. bickii with genomic DNA (gDNA) of G. bickii as a probe, two sets of chromosomes, consisting of 26 chromosomes each, were easily distinguished from each other by their distinctive hybridization signals. GISH analysis directly proved that the hybrid G. arboreum x G. bickii is an allotetraploid amphiploid. The karyotype formula of the species was 2n = 4x = 52 = 46m (4sat) + 6sm (4sat). We identified four pairs of satellites with two pairs in each sub-genome. FISH analysis using 45S rDNA as a probe showed that the cross G. arboreum x G. bickii contained 14 NORs. At least five pairs of chromosomes in the G sub-genome showed double hybridization (red and blue) in their long arms, which indicates that chromatin introgression from the A sub-genome had occurred.
Hao
Lin
L
Shanxi Agricultural University, Taigu, China.
Song
Guo-Li
GL
Li
Bing-Lin
BL
Wang
Kun-Bo
KB
Wang
Chun-Ying
CY
Li
Xin
X
D002843:Chromatin; D032461:Chromosomes, Plant / Q000000981:diagnostic imaging / Q000235:genetics*; D003433:Crosses, Genetic; D004275:DNA, Ribosomal / Q000032:analysis; D018745:Genome, Plant; D003368:Gossypium / Q000235:genetics* / Q000648:ultrastructure; D007621:Karyotyping; D009693:Nucleic Acid Hybridization / Q000379:methods*; D011123:Polyploidy; D014463:Ultrasonography
D002843:Chromatin; D004275:DNA, Ribosomal