Variation in tolerance to drought among Scandinavian populations of Arabidopsis lyrata

Abstract

The ability to cope with water limitation influences plant distributions, and several plant traits have been interpreted as adaptations to drought stress. In Scandinavia, the perennial herb Arabidopsis lyrata occurs in open habitats that differ widely in climate and water availability in summer, suggesting differential selection on drought-related traits. We conducted two greenhouse experiments to examine differentiation in drought response traits among six Scandinavian populations, and to determine whether leaf trichomes confer protection against drought. We quantified tolerance to drought as fitness (survival and biomass of survivors) when exposed to drought relative to fitness under non-drought conditions. Two Swedish populations from shores along the Bothnian Bay had higher tolerance to drought than four riverbed populations from Norway. Under conditions of drought, the shore populations experienced less leaf damage compared to the riverbed populations, and their survival and biomass were less reduced relative to non-drought conditions. Across populations, tolerance to drought was positively related to leaf mass per area and negatively related to flowering propensity and proportion roots, but not related to plant size at the initiation of the drought treatment. In populations polymorphic for trichome production, trichome-producing plants were more tolerant to drought than glabrous plants. The results suggest that both leaf morphology and life-history traits contribute to differential drought response in natural populations of A. lyrata, and that this system offers excellent opportunities for examining the adaptive value and genetic basis of drought-related traits.

Functional trait divergence and trait plasticity confer polyploid advantage in heterogeneous environments

“… References for trait function: SLA (Poorter et al ., ); SD and SL (Hetherington & Woodward, ); VLA (Sack & Scoffoni, ); TD (Ehleringer & Björkman, ; Sletvold & Ågren, ); N mass (Wright et al ., ); Δ 13 C (Farquhar & Richards, ). …”

Genome duplication effects on functional traits and fitness are genetic context and species dependent: studies of synthetic polyploid Fragaria

“…We measured five leaf functional traits that are relevant to fitness of diploid and polyploid Fragaria in the wild (Wei et al., 2019a). These traits include stomatal length (i.e., abaxial guard cell length, μm) and stomatal density (i.e., number of abaxial stomata per mm leaf area), both of which regulate plant CO 2 intake and water transpiration (Hetherington and Woodward, ); specific leaf area that estimates the light‐capturing leaf area per unit investment of dry mass (mm 2 mg −1 ) and influences leaf carbon gain (Poorter et al., ); leaf vein density (i.e., minor vein length (mm) per mm leaf area) that reflects hydraulic conductance (Sack and Scoffoni, ); and trichome density (i.e., total number of abaxial and adaxial trichomes per mm leaf area), which can protect plants against water loss (Ehleringer and Björkman, ; Sletvold and Ågren, ), as well as herbivore damage (Hanley et al., ).…”

STRONG INBREEDING DEPRESSION IN TWO SCANDINAVIAN POPULATIONS OF THE SELF-INCOMPATIBLE PERENNIAL HERBARABIDOPSIS LYRATA

“…In 2007, we collected seeds from 50 plants in each of two large Scandinavian A. lyrata populations (>2000 individuals): an alpine population in Norway (Spiterstulen; 1100 m a.s.l., 61°41′N, 8°25′E), and a coastal population in Sweden (Stubbsand; <5 m a.s.l., 63°13′N, 18°58′E). The study populations are substantially differentiated at putatively neutral microsatellite loci (Gaudeul et al ), as well as in phenotypic traits such as flowering phenology (Sandring et al ), leaf trichome production (Løe et al ), and tolerance to drought (Sletvold and Ågren ).…”