Cytogenetics, morphological, yield, and molecular characterization of the Portuguese bread wheat “Barbela”

Abstract

“Barbela” (Triticum aestivum L. em. Thell) constitutes an aggregate of Old Portuguese landraces highly genetically diverse. We characterized 30 “Barbela” populations from four regions at the cytogenetic, molecular, morphological, and yield levels. The hexaploid wheat “Chinese Spring” was included in all analyses as a control. No polymorphisms at the nucleolar organizer regions were detected. Instead, he intergenic spacer (IGS) polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) markers identified four IGS length variant phenotypes within “Barbela” and one in “Chinese Spring”. The Unweighted Pair Group Method with Arithmetic Mean (UPGMA) clustering based in these markers reflected the IGS length variant phenotypes identified. Inter-Simple Sequence Repeat (ISSR) markers revealed high genetic variability within “Barbela” and between “Barbela” and “Chinese Spring”. Consequently, “Chinese Spring” was clustered apart from “Barbela” in the UPGMA tree constructed based on the pooled ISSR data. At the morphological and yield levels, statistical significant effects of region and population were detected for most of the characters evaluated. The relatedness of “Barbela” and “Chinese Spring” was closest when assessed by morphological and yield characters, confirming the low specificity of these marker systems when compared with the molecular ones used here (ISSRs and IGS PCR-RFLPs).

Keywords:

• “Barbela”
• cytogenetic and molecular markers
• genetic variability
• morphological and yield characters
• Triticum aestivum L. em. Thell

Acknowledgment

This work was supported by the PTDC/AGR-GPL/65876/2006 project and the Ph.D. grant SFRH/BD/17348/2004 financed by the Portuguese Foundation for Science and the Technology.