We resolved the evolutionary history for one of the world’s worst weeds Chenopodium album s. str. by analysing sequence variation in the nrDNA ITS region and the rpl32-trnL intergenic spacer of cpDNA and performed genomic in-situ hybridization (GISH). Our study confirms the allohexaploid origin of C. album s. str. We showed that C. album s. str. is a hybrid between diploid (C. suecicum or C. ficifolium) and tetraploid (C. strictum or C. striatiforme) species with tetraploid species serving as a mother plant. Moreover we proved at least two different allopolyploid lineages, indicating a polyphyletic origin of C. album s. str. and also showed that some individuals of C. album s. str. probably evolved very recently. These results indicate that hybridization as a process was very important in Chenopodium evolutionary history and in some cases represent ongoing process resulting in wide morphological variability especially in C. album s. str.
Krak K., Vít P., Belyayev A., Douda J., Hreusová L. & Mandák B. (2016): Allopolyploid origin of Chenopodium album s. str. (Chenopodiaceae): A molecular and cytogenetic insight. PLoS ONE 11(8): e0161063. doi:10.1371/journal.pone.0161063.
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