Molecular analyses on the genetic diversity and inheritance of (-)-alpha-bisabolol and chamazulene content in tetraploid chamomile (Chamomilla recutita (L.) Rausch.)

摘要

The study aims to analyse (i) the genetic diversity of cultivated chamomile germplasm, (ii) to possibly discriminate chemotypes and (iii) to develop molecular markers for the (-)-alpha-bisabolol and chamazulene content by using RAPD and AFLP marker analysis.By analysing di- and tetraploid chamomile (Chomomilla recutita (L.) RatISCh.) accessions using 18 RAPD primers and 16 ECoRI + 3/ Msel + 3 AFLP primer combinations genetic similarity (GS(D)) was estimated in a range of 0.68-0.95 (RAPDs) and 0.74-0.88 (AFLPs), respectively. UPGMA-cluster analysis revealed two main groups and additional sub-clusters according to the origin of germplasms but not to the phytochemical composition. In lines selected for the development of segregating populations for marker development a high level of genetic homogeneity within (GS(D) approximate to 0.9; H' approximate to 0.1) but diversity between lines (GS(D) approximate to 0.7; H' approximate to 0.5) was detected which facilitated the selection of contrasting parental genotypes with respect to (-)-alpha-bisabolol and chamazulene content as well as genome composition. Segregation analysis of 841 F2-individuals revealed a monogenic recessive mode of inheritance of the (-)-alpha-bisabolol and chamazulene content. By bulked segregant analysis three AFLP-markers linked to the (-)-alpha-bisabolol locus and one RAPD and 17 AFLP markers for the chamazulene content were detected. At least the markers for the chamazulene content are suited for pre-flowering marker based selection procedures. (c) 2005 Elsevier Ireland Ltd. All rights reserved.