It is important to optimize strategies for collecting wild germplasm from their natural habitats for the successful conservation of plant genetic resources. We studied the population structure of three predominantly self-pollinating wild Lactuca species (Lactuca serriola, L. saligna, and L. aculeata). Seeds for this study were collected from individual plants in northern Israel, along a line transect, and two populations per each Lactuca species. The distance between neighboring plants sampled for seeds varied from 1.5 to 37 m. The transect length at single sites ranged from 47.2 to 151.8 m. The taxonomic status of 67 individual plants was morphologically validated during greenhouse multiplication. Both genetic structure and diversity were analyzed by using 11 EST–SSR loci and 230 AFLP markers. Relatively low genetic diversity values were observed, increasing in the following order: L. aculeata < L. serriola < L. saligna. Network analysis clearly separated samples according to their taxonomic determination; also reflecting the gene diversity as well as the genetic distance values among the three species. Nevertheless, given the predominantly selfing character of these species, populations were not uniform (genetically and morphologically). It seems that overall genetic variation in a population increases at its periphery, due to the presence of plants with “non-indigenous” alleles, which are most likely coming from migration and subsequent interpopulation or interspecific hybridization. Mantel tests generally indicated a positive association between genetic distance and micro-geographical distance of a particular population, primarily due to the “outlier” samples collected at a population’s periphery.
Bibliographical noteFunding Information:
M.K., L.M., E.K., M.J., A.L. were supported by the Internal Grant Agency of Palacký University in Olomouc (PrF-2013-003, and IGA_Prf_2014001), Project MSM 6198959215 (Ministry of Education, Youth and Sports), and Project QH 71254 (Czech Ministry of Agriculture); and LM was supported by the European Social Fund, Education for Competitiveness Operational Programme (CZ.1.07/2.3.00/30.0004). AB wishes to thank the Research Authority, University of Haifa, Israel for financial support for the collection of Lactuca germplasm. The authors wish to thank Mrs. Drahomíra Vondráková (Palacký University in Olomouc), Ms. Souad Khalifa (University of Haifa) for their technical assistance, and anonymous reviewer for constructive comments and suggestions which helped us to improve the manuscript.
© 2014, Springer Science+Business Media Dordrecht.
- Collecting strategy
- Genetic variability
- Lactuca saligna
- Lactuca serriola
- Population genetic structure
- Wild lettuce
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Agronomy and Crop Science
- Plant Science