Robson, T. M., Rasztovits, E., Aphalo, P. J., Alia, R. & Aranda, I. Flushing phenology and fitness of European beech (Fagus sylvatica L). provenances from a trial in La Rioja, Spain, segregate according to their climate of origin.
Given the sensitivity of CHH methylation to growth temperature observed here, we next investigated the correlation between DNA methylation and the climate of origin (Hancock et al., 2011).
We used ClimatePC1 and ClimatePC2 to test hypotheses that climate of origin is associated with variation in both thermotolerance and Hsp101 expression.
That we only detect an association of variation in seedling survival, post-heat root growth or Hsp101 expression with climate of origin under some circumstances suggests three additional explanations for the observed population variation.
Population-level studies exploring the relationship among the climate of origin, differentiation in thermotolerance and the role of changes in gene expression in acquired thermotolerance are needed to improve understanding of optimal heat stress responses in plants.
The natural selection a population was subjected to seems to be weakly reflected in developmental time, since an increase in the duration of development is observed only at one stressful developmental temperature according to the climate of origin of a population.
We further tested whether variation in thermotolerance and Hsp101 expression matched with variation in the climates of population origin.
The climates of population origin, quantified as ClimatePC1 and ClimatePC2 values, were used to examine the evolved effect of past climate on both the population mean thermotolerance measures (per cent seedling survival and post-stress root growth) and on Hsp101 expression.
Tourist flows are affected by social and financial costs of travel and by changing climates in countries of origin, though with little response as yet.
Although in this case, the type of micro-evolutionary process responsible is not directly demonstrated, the processes were found to cluster bi-directionally depending on climate of population origin.
