Genetic structure of Aegilops cylindrica Host in its native range and in the United States of America

• Published in: Theoretical and applied genetics Vol. 119; no. 6; pp. 1013 - 1025
• Main Authors: Gandhi, Harish T, Vales, M. Isabel, Mallory-Smith, Carol, Riera-Lizarazu, Oscar
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.10.2009; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Aegilops cylindrica; Agriculture; Biochemistry; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Cell Nucleus - genetics; Chloroplasts; Chloroplasts - genetics; Classical genetics, quantitative genetics, hybrids; Cytoplasm; Fundamental and applied biological sciences. Psychology; Genetic diversity; Genetic Markers; Genetic Structures; Genetic Variation; Genetics of eukaryotes. Biological and molecular evolution; Genomes; Geography; Goat grass; Hybridization, Genetic; Iraq; Life Sciences; Microsatellite Repeats; Original Paper; Plant Biochemistry; Plant Breeding/Biotechnology; Plant Genetics and Genomics; Poaceae - genetics; Pteridophyta, spermatophyta; Soil sciences; Transcaucasia; Turkey; United States; Vegetals; United States; North America; America; Transcaucasia; Turkey; Iraq; Greece; Lebanon; Oregon; Iran; United States > US; Asia; Europe; Bulgaria; Syria; Native Range; Diploid Progenitor; Iraq; Allelic Richness; Nuclear Marker; Monocotyledones; Aegilops; Molecular structure; Gramineae; Angiospermae; Host range; Genetics; Spermatophyta; Agriculture
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-009-1105-3

Chloroplast and nuclear microsatellite markers were used to study genetic diversity and genetic structure of Aegilops cylindrica Host collected in its native range and in adventive sites in the USA. Our analysis suggests that Ae. cylindrica, an allotetraploid, arose from multiple hybridizations between Ae. markgrafii (Greuter) Hammer. and Ae. tauschii Coss. presumably along the Fertile Crescent, where the geographic distributions of its diploid progenitors overlap. However, the center of genetic diversity of this species now encompasses a larger area including northern Iraq, eastern Turkey, and Transcaucasia. Although the majority of accessions of Ae. cylindrica (87%) had D-type plastomes derived from Ae. tauschii, accessions with C-type plastomes (13%), derived from Ae. markgrafii, were also observed. This corroborates a previous study suggesting the dimaternal origin of Ae. cylindrica. Model-based and genetic distance-based clustering using both chloroplast and nuclear markers indicated that Ae. tauschii ssp. tauschii contributed one of its D-type plastomes and its D genome to Ae. cylindrica. Analysis of genetic structure using nuclear markers suggested that Ae. cylindrica accessions could be grouped into three subpopulations (arbitrarily named N-K1, N-K2, and N-K3). Members of the N-K1 subpopulation were the most numerous in its native range and members of the N-K2 subpopulation were the most common in the USA. Our analysis also indicated that Ae. cylindrica accessions in the USA were derived from a few founder genotypes. The frequency of Ae. cylindrica accessions with the C-type plastome in the USA (~24%) was substantially higher than in its native range of distribution (~3%) and all C-type Ae. cylindrica in the USA except one belonged to subpopulation N-K2. The high frequency of the C-type plastome in the USA may reflect a favorable nucleo-cytoplasmic combination.