SIERRA NEVADA

The mountain jewelflower inhabits a wide swath of California and Oregon, from summer-scorched foothills to high mountains where snow falls during winter. But it is already suffering from climate change, with plants in the mountains struggling to survive both summers and winters.

A strategy called assisted gene flow could reshuffle the plant’s gene variants into new combinations that better match the new climates. The same strategy could also help many other plant species.

As temperatures warm, California has seen frequent droughts, with reduced snowpack and earlier snowmelt in the Sierra Nevada. Conditions at high elevations have become more like what low elevations experienced in the past. This has shifted the timing of growing seasons and altered the conditions that plants experience during them.

At a site high in the Sierra, UC Davis researchers planted seedlings from various regions of California — including both high-elevation areas and lower, warmer, drier areas. 

During the first summer, the high-elevation plants survived and produced seeds at lower rates than the lowland plants did. Surprisingly, when UC Davis postdoctoral scholar Brandie Quarles-Chidyagwai returned the following June, she found that the high-elevation plants had once again fared worse, surviving the winter at lower rates than the plants from lower, warmer areas.

This suggested that these high-elevation plants were no longer well-adapted to their environment, suffering not only through a hot, dry summer, but also through a winter when the snow was unusually thin, providing the plants with less protection.

Quarles-Chidyagwai and UC Davis Professors Jenny Gremer and Julin Maloof are now doing assisted gene flow experiments to combine those gene variants into a single population of plants. 

By interbreeding mountain jewelflowers from high and low elevations, “we can hopefully get the ideal combination of genes and create an ideal plant” for these new climates, Quarles-Chidyagwai said.

~ UC Davis press release