Morphometric traits in the fine-leaved fescues depend on ploidy level: the case of L.

BACKGROUND

Polyploid specimens are usually characterized by greater exuberance: they reach larger sizes and/or have a larger number of some organs. L. belongs to the section . Based on morphological features, four subspecies of have been already identified. On the other hand, it has two cytotypes: diploid and tetraploid. The main aim of our study was to distinguish morphological differences between the cytotypes of , assuming that its phenotype differs significantly.

METHODS

The nuclear DNA content was measured by flow cytometry in dry leaves from specimens originating from 13 populations of . Several macrometric and micrometric traits of stems, spikelets and leaf blades were taken into account in the comparative analysis of two cytotypes.

RESULTS

In the case of cytotypes, specimens of tetraploids were larger than diploids. The conducted morphometric analysis of leaf cross-sections showed significant differences between the cytotypes.

DISCUSSION

The research has confirmed for the first time that in the case of the principle of greater exuberance of polyploids is true. Differences between the cytotypes are statistically significant, however, they are not enough to make easy the distinction of cytotypes on the basis of the measurements themselves. Our findings favor the rule known in taxonomy as a whole, i.e. that the ploidy level can be one of the main classification criteria.