Local differences persist in a wind-pollinated grass after two generations in a common garden

A new study by H. M. Odongo, M. Halassy, A. M. Csergő and K. Török, published in Plants, examined how consistently differences among populations of Festuca vaginata—a dominant grass of Hungary's open sandy grasslands—persist when plants are grown under common environmental conditions.

Using a two-generation common-garden experiment with uncontrolled gene flow, the researchers compared seed germination and seedling traits across seed transfer zones and localities. They found that population differences in germination disappeared in the second generation, whereas differences in biomass and leaf length persisted. This indicates that traits can differ in their transgenerational stability and that shared environmental conditions may homogenize some traits more rapidly than others.

The results also highlight the limitations of relying solely on broad seed transfer zones when sourcing wind-pollinated grasses for ecological restoration. While the findings do not challenge the usefulness of seed transfer zones, they suggest that locality-level variation may provide additional information for seed sourcing, particularly for traits showing persistent population differentiation.

Reference: Odongo, H. M., Halassy, M., Csergő, A. M., & Török, K. (2026). Trait-Specific Patterns of Phenotypic Differentiation Among Populations After Two Generations of Common-Garden Cultivation in a Wind-Pollinated Grass. Plants, 15(17), 2556. https://doi.org/10.3390/plants15172556