Effects of light and water availability on shoot dynamics of the stoloniferous Linnaea borealis

• Many stoloniferous plant species have the ability to exploit resource-rich patches via plastic growth responses. The most efficient responses are shortened spacers and increased branching frequency. Here we experimentally investigate the ability of the stoloniferous plant Linnaea borealis to respond to patches of increased light intensity and reduced water availability in natural systems. The significance of contrasts between patches was also investigated. A three-level factorial design was used, with light, water availability, and site as the factors. Increased light intensity was achieved through mowing of the surrounding vegetation, and reduced water availability was achieved by placing wooden ledges under the stolons. The treatments were applied at three subarctic sites that differ in light conditions. Branching frequency, number of new meristems, average internode length, leaf area, and dry weight production were studied 14 months after the manipulations. Increased light intensity increased branching frequencies; the strongest effects were obtained at the site with a closed canopy. Average intemode length decreased 19% in response to increased light intensity. Root:shoot ratios decreased under increased light intensity and reduced water availability. A reduction in water availability alone did not affect any other investigated traits. We conclude that ramets of L. borealis are able to respond efficiently to small-scale variations in light intensity in natural systems, an ability of great importance for the performance of a prostrate species on shady forest floors.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Keyword

branching frequency

clonal plant

division of labour

foraging

patch quality

Biology

Biologi

Publication and Content Type

ref (subject category)

art (subject category)