Acknowledgements
We thank Dr. Irene V¨anninen, MTT Jokioinen, Finland,
for her comments on the manuscript, Timo Oksanen for
programming the climate chambers and Jaana Rissanen for
assistance in the laboratory work. This work was financially
supported by Jenny & Antti Wihuri Foundation, Finnish
Cultural Foundation, and the Ministry of Agriculture and
Forestry in Finland, Project number 310061. The language
text was revised by Ewen Macdonald.