Suppression of Arabidopsis flowering by near‐null magnetic field is affected by light

We previously reported that a near‐null magnetic field suppressed Arabidopsis flowering in white light, which might be related to the function modification of cryptochrome (CRY). To further demonstrate that the effect of near‐null magnetic field on Arabidopsis flowering is associated with CRY, Arabidopsis wild type and CRY mutant plants were grown in the near‐null magnetic field under blue or red light with different light cycle and photosynthetic photon flux density. We found that Arabidopsis flowering was significantly suppressed by near‐null magnetic field in blue light with lower intensity (10 µmol/m 2 /s) and shorter cycle (12 h period: 6 h light/6 h dark). However, flowering time of CRY1/CRY2 mutants did not show any difference between plants grown in near‐null magnetic field and in local geomagnetic field under detected light conditions. In red light, no significant difference was shown in Arabidopsis flowering between plants in near‐null magnetic field and local geomagnetic field under detected light cycles and intensities. These results suggest that changes of blue light cycle and intensity alter the effect of near‐null magnetic field on Arabidopsis flowering, which is mediated by CRY. Bioelectromagnetics. 36:476–479, 2015. © 2015 Wiley Periodicals, Inc.