Genetic diversity of the expansive grass Brachypodium pinnatum in a changing landscape: Effect of habitat age

Acclimatization of Photosynthetic Apparatus of Tor Grass (Brachypodium pinnatum) during Expansion

“…100 years old: Dolina Kobylańska [19°45′42.06′′E, 50°9′27.33′′N], Skala Żytnia [19°47′54.96′′E, 50°11′14.72′′N], WielkieSkały [19°48′20.17′E 50°11′23.49′′N], Bolechowice [19°46′58.08′′E, 50°9′11.28′′N], and old >300 years: Grodzisko [19°49′46.55′′E, 50°13′36.39′′N], Grodzisko-Onobrychis [19°49′36.86′′E, 50°13′40.54′′N], Dolina Będkowska [19°44′21.28′′E, 50°8′49.44′′N] and Dolina Kluczwody [19°49′7.04′′E, 50°9′49.94′′N]. Moreover, according to the results of the previous population genetic analyses based on AFLP markers, it was possible to relate age to genotypic richness ( G ) and the percentage of polymorphic loci ( PPL ), which decreased with the habitat age [ 6 , 15 ]. The other criteria for classification of Brachypodium populations were the differences in genotypic diversity and morphological parameters of its clones.…”

“…It forms clones, usually up to 1.5 (max 4) m in diameter with ca. 80% short rhizomes (1–10 mm) and dense tillers in form of 'clumps of shoots' (3–5 cm diameter) connected with longer rhizomes (100–200 mm) [ 15 ]. This enables it the long-term occupation of a given area and quick lateral spread.…”

“…The annual average temperature is 7.5°C in vegetation period and mean annual precipitation reaches 773 mm. Brachypodium occurs on the S, SW and SE slopes, and sometimes forms nearly monodominant stands [ 15 , 29 ]. 12 Brachypodium -dominated calcareous grasslands were selected for establishment of the study plots (250 m 2 50 x 50 m).…”

“…The other criteria for classification of Brachypodium populations were the differences in genotypic diversity and morphological parameters of its clones. According to the results of previous population genetic analyses based on AFLP markers, it was possible to relate age to genotypic richness ( G ) and the percentage of polymorphic loci ( PPL ), which both decreased with the habitat age [ 6 , 15 ]. Moreover, the average shoots and 'clumps of shoots' density/1m 2 [ 9 ],the number of leaves in clumps of shoots/1m 2, (given in S1 – S3 Figs), roots and rhizome dry biomass increased with habitat age S4 and S5 Figs).…”

“…Deposition of airborne nitrogen and phosphorus is considered to be a second possible reason for its expansion in Western Europe [ 7 , 8 ]. Numerous aspects of biology have been reported to date including the plastic response to light conditions [ 8 ], biomass and nutrient allocation, nutrient cycling [ 9 – 11 ], mycorrhizal colonization [ 12 ] karyotype evolution [ 13 ] and the population genetic diversity of this species along colonization gradients or under different management [ 6 , 14 , 15 ]. Moreover, several attempts have been made to control the Brachypodium expansion [ 16 , 17 ].…”