Plants adapt their flowering time to the temperature in their surroundings. Relatively little is known about how plants delay their flowering time during a cold spring. Global warming minimizes fluctuations in temperature. A better understanding of these impacts is important for plant breeding to ensure that food production can be guaranteed in the long term.

Claus Schwechheimer, Technical University of Munich (TUM), Germany, and colleagues discovered a molecular mechanism that causes Scottish thale cress Arabidopsis thaliana to flower two weeks earlier than its counterparts in warmer regions. They also found a way to predict the flowering time. The insertion of a transposon, a jumping gene, results in very low formation of a crucial flowering gene. The function of the flowering repressor no longer had any effect.

The researchers showed that this gene mutation has already become established in several other variants of the thale cress and controls flowering behavior in them. Moreover, they were able to predict the flowering behavior of the thale cress based on the presence of the transposon with a high degree of accuracy. The researchers think it will soon be possible to transfer this knowledge to the flowering behavior of crop plants like rapeseed, and predict and even modify their flowering time.

• Modulation of Ambient Temperature-Dependent Flowering in Arabidopsis thaliana by Natural Variation of FLOWERING LOCUS M,
  Christian S Hardtke, Ulrich Lutz, David Posé, Matthias Pfeifer, Heidrun Gundlach, Jörg Hagmann, Congmao Wang, Detlef Weigel, Klaus F. X. Mayer, Markus Schmid, Claus Schwechheimer,
  PLOS Genet. 2015, 11, e1005588.
  DOI: 10.1371/journal.pgen.1005588