In total, seventy two Lactuca aculeata and three Lactuca serriola samples originating from natural populations of these species in Turkey, Jordan, and Israel were analysed by eight microsatellite and 287 amplified fragment length polymorphism (AFLP) markers. Neighbor-Network and Bayesian clustering were used for visualisation of the differences among the analysed L. aculeata and L. serriola samples, and to confirm hybrid origin (L.aculeata×. L. serriola) of three samples (343-8A, 343-8B, 54/07) previously indicated by their morphological traits. Molecular data reflect the geographical origin, i.e., the clustering of samples according to their country of origin. Samples from neighbouring parts of Jordan and Israel expressed similar genetic characteristics, indicating the possibility of migration or artificial introduction of plant material. Forty-one L. aculeata samples were screened for their response to five Bremia lactucae races (Bl: 17, Bl: 18, Bl: 24, Bl: 27, and Bl: 28). Susceptible reactions of L. aculeata prevailed. L. aculeata samples were most frequently susceptible to races Bl: 18, Bl: 24, Bl: 27, Bl: 28; and least susceptible to Bl: 17. No highly efficient source of resistance was detected; however, race-specific reaction patterns were frequently recorded, indicating the possible presence of some race-specific resistance factors/genes in the studied samples of L. aculeata. Conservation and exploitation of this material in lettuce breeding is discussed.
Bibliographical noteFunding Information:
The research was supported by projects MSM 6198959215 ( Ministry of Education, Youth and Sports ), QH 71254 ( Ministry of Agriculture ), and the Internal Grant Agency of Palacký University in Olomouc ( PrF-2013-003 , IGA_Prf_2014001 , IGA_Prf_001-2015 ). The authors express their sincere thanks to Dr. Irena Petrželová for her critical comments on the first draft of the manuscript, and to Mrs. Drahomíra Vondráková and Ms. Souad Khalifa (University of Haifa) for their technical assistance.
© 2015 Elsevier Ltd.
- Genetic diversity
- Lettuce downy mildew
- Microsatellite and AFLP genotyping
- Middle East
- Race-specific resistance
- Wild lettuce conservation
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics