Physical localization of NORs and ITS length variants in old Portuguese durum wheat cultivars

Journal of genetics

Ana Carvalho¹  José Lima-Brito1¹  Henrique Guedes-Pinto¹ 

[1] Institute of Biotechnology and Bioengineering (IBB), Centre of Genomics and Biotechnology (CGB), University of Tras-os-Montes and Alto Douro, P. O. Box 1013, 5001-801 Vila Real, Portugal$$

关键词: fluorescence in situ hybridization (FISH);    internal transcribed spacer (ITS);    nucleolar organizer region (NOR);    PCR-RFLP;    Triticum turgidum subsp.durum (Desf.);    Triticum turgidum subsp. dicoccum.;   

DOI  :  

学科分类：生物科学（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The variation at the internal transcribed spacer (ITS) region of the ribosomal DNA has been correlated with the number of nucleolar organizer regions (NORs) in some plant species. Besides, the number of NORs might influence the rate of homogenization of the rDNA repeats. In recent studies, ITS length variants were detected in bread wheat cultivars but no reports about their presence in durum wheat were found. In the present study, we localized and identified the NORs of 51 old Portuguese durum wheat cultivars by using sequential silver staining and fluorescence in situ hybridization performed with the pTa71 rDNA probe. We also detected ITS length variants by PCR-RFLP. No variation at the number of Ag-NORs per metaphase was found among the 51 durum wheat cultivars, but the PCR-RFLP technique carried out with the restriction enzyme HpaII, allowed the detection of ITS length variants among them. The molecular data was used in order to establish the genetic relationships among cultivars and botanical varieties of durum wheat. The knowledge of this feature could be useful for future design of breeding strategies, involving this collection that constitutes an excellent repository of germplasm in Portugal.

【 授权许可】

Unknown