Phenotypic and Genotypic Variation in Czech Forage, Ornamental and Wild Populations of Reed Canarygrass

Abstract

Reed canarygrass (Phalaris arundinacea L.) is native to Europe and North America, being invasive in the latter since the 20th century. No phenotypic differences have been found in plants from each continent; genetic analyses have been controversial—implicating or exonerating forage/ornamental cultivars for spread throughout North America. Within central Europe, particularly the Czech Republic, it is unknown whether wild genotypes and cultivars are genetically and phenotypically similar. The objectives of this study were to compare commercial forage and ornamental cultivars sold within the Czech Republic with wild genotypes from native populations along major Czech rivers and characterize the extent of phenotypic and genetic variation. Several phenotypic traits differentiated among genotypes and populations (initial tiller fresh weight, stem dry weight [DW], whole plant above‐ and belowground DW, total no. of tillers, percent cover, crown area, height, leaf and node number). Genetic markers (inter‐simple sequence repeats [ISSRs]) clearly differentiated ornamental cultivars from wild P. arundinacea. ‘Chrastava’, the Czech forage and biomass cultivar was genetically similar to wild genotypes, which have most of the genetic diversity within, rather than among, populations. Cluster analyses showed ornamental cultivar ramets to be heterogeneous, most likely due to clonal mix up or mutations.

Genetic Variability of US and Czech Phalaris Arundinacea L. Wild and Cultivated Populations

“…ISSRs or inter-simple sequence repeats, for the irst time ever, showed distinct genetic diferences between ornamental cultivars and wild P. arundinacea [18]. Interestingly, the Czech forage and biomass cultivar, 'Chrastava', could not be diferentiated from the same wild populations.…”

“…Existing forage and ornamental cultivars resulted from as few as 1-2 selections and sexual recombination cycles removed from wild types [16], such as 'Chrastava', domesticated in the Czech Republic [17]. 'Chrastava' was genetically similar to wild Czech populations while all other ornamental cultivars difered [18]. High levels of seed dormancy, seed shatering, and low yield potential exist in most populations, e.g.…”

“…Current breeding is focused on improving of its yield potential as a fodder crop as well as for wastewater treatment plants and, more recently, biomass production. Phalaris is often used in gardening and ornamental horticulture [18]. It is cultivated mainly as decorative plants with longitudinal white or yellow variegated cultivars from the group Phalaris arundinacea var.…”

“…Invasive genotypes possess wide genotype × environment (G×E) interactions across environments for emergence, tiller production, leaf number and biomass, indicating a lack of stability and wide genetic variation [28][29][30]. Recent molecular studies have shown that central European (Czech) wild populations were genetically similar to the forage 'Chrastava' while difering signiicantly from ornamental cultivars [18]. In contrast, within MN populations, forage/ornamentals were genetically similar to wild types [31].…”

“…Previous work by our labs [18,31] analyzed phenotypic and genotypic markers in genotypes obtained from wild populations growing along the six main rivers within the Czech Republic (Berounka, Dyje, Labe, Lužnice, Orlice, Vltava) and commercial cultivars (forage, ornamental types) grown in the Czech Republic to serve as a foundation for Central European reed canarygrass diversity. ISSRs or inter-simple sequence repeats, for the irst time ever, showed distinct genetic diferences between ornamental cultivars and wild P. arundinacea [18].…”