Latitudinal variation in plant size and relative growth rate in Arabidopsis thaliana

Abstract

Latitude is an important determinant of local environmental conditions that affect plant growth. Forty ecotypes of Arabidopsis thaliana were selected from a wide range of latitudes (from 16°N to 63°N) to investigate genetic variation in plant size and relative growth rate (RGR) along a latitudinal gradient. Plants were grown in a greenhouse for 31 days, during which period three consecutive harvests were performed. Plants from high latitudes tended to have smaller plant size in terms of seed size, cotyledon width, rosette size, number of rosette leaves, size (leaf area) of the largest leaves, total leaf area, and total dry weight per plant than those from low latitudes. The mean (±SE) RGR across ecotypes was 0.229 (±0.0013) day. There was, however, significant ecotypic variation, with RGR being negatively correlated with latitude. The two main components of RGR, leaf area ratio (LAR) and unit leaf rate (ULR), were also correlated with latitude: LAR increased with increasing latitude while ULR decreased with increasing latitude. It was also found that RGR tended to be negatively correlated with LAR, specific leaf area (SLA) and specific root length (SRL) but to be positively correlated with mean area per leaf (MAL) and ULR. The variation in RGR among ecotypes was relatively small compared with that in the other traits. RGR may be a conservative trait, whose variation is constrained by the trade-off between its physiological (i.e. ULR) and morphological (i.e. LAR) components.

Salicylate Accumulation Inhibits Growth at Chilling Temperature in Arabidopsis

“…Arabidopsis is widely distributed in northern temperate regions and RGRs and NARs of ecotype accessions both correlate negatively with latitude of origin (Li et al, 1998). Our conclusion that NAR determined the RGR differential between Col-0 and NahG accords with the correlation between these two growth parameters in the ecotypes studied by Li et al (1998).…”

The roles of genetic drift and natural selection in quantitative trait divergence along an altitudinal gradient in Arabidopsis thaliana

“…Similarly, leaf production and plant size decreased along latitude that is correlated with a decrease in temperature at a larger scale (Li et al, 1998). Note that in these studies and in our study, rosette leaf number and rosette diameter after a defined period of time are used as measures of growth; in our study, rosette leaf number and rosette diameter after 3 weeks were not correlated with flowering time (Supplementary Table S5).…”

“…In A. thaliana, specific leaf area decreases with latitude of origin (Li et al, 1998). In other species, specific leaf area was shown to decrease with either altitude or drought or with both factors (e.g., Hovenden and Vander Schoor, 2004;Gonzalo-Turpin and Hazard, 2009;Ramirez-Valiente et al, 2010;Scheepens et al, 2010) and this is also the pattern observed between species (Körner, 1999(Körner, , 2003Niinemets, 2001;Poorter et al, 2009).…”

Ecotypic differentiation in seed and seedling morphology and physiology among Cicuta virosa populations

“…The variation in mean RGR over a period of 4 weeks was significant in C. virosa populations (Table 2) and similar to the intraspecific variation in A. thaliana and other herbaceous plants (Meerts and Garnier, 1996;Li et al, 1998;Van Rijn et al, 2000). The instantaneous root: shoot ratio in any individual plant is subjected to genetic, ontogenetic, and environmental control (Gedroc et al, 1996).…”

“…plant size and relative growth rate of Arabidopsis thaliana (Li et al, 1998), germination and seedling desiccation tolerance of Hordeum spontaneum local ecotypes in Israel (Gutterman and Gozlan, 1998), flowering time in some A. thaliana ecotypes (Nordborg and Bergelson, 1999), dormancy and freezing tolerance in Betula pendula Roth (Li et al, 2003), and physiological and growth responses in Populus davidiana ecotypes (Zhang et al, 2005)). Those studies established the patterns of responses to the environment and adaptation traits to a given environment.…”