Population dynamics of polymorphism for marker traits in populations of Thinopyrum intermedium

Search for morphological traits that are essential for adaptive potential of the species and variable in different environments is an important part of microevolutional studies, as well as intraspecific and introgressive hybridization. Methods. Measuring and visual assessment of spike morphology. Results. Plants from five populations of Thinopyrum intermedium grown in different microgeografic conditions have been assessed for qualitative (spike color, spike hairiness, glume characteristics) and quantitative (flower number, spikelet number, spike length, spikelet length, distance between spikelets) spike morphology traits. Their associative variability for two years and its role in formation of morphotypes in populations have been investigated. The difference of average values of spike quantitative traits indicates the impact of microgeografic conditions and climate on morphotype formation. Associated manifestations of awns and shape of glume arm, arm shape and keel shape, some pairs of quantitative and qualitative traits either have been registered in both years of study or were characteristic for some particular year, and could have played role in plants’ adaptation to abiotic conditions. Conclusions. In populations of Thinopyrum intermedium grown in different conditions, dynamic polymorphisms for qualitative and quantitative traits are important for plants’ adaptability. Differences in average values of spike quantitative traits have been determined among all populations and years, which indicates the influence of microgeografic conditions and climate on these traits.