Cell cycle inhibitors improve seed storability after priming treatments.

Seed priming is a treatment that controls seed water content to partially activate germination processes such as metabolism but prevents full germination of the seeds. The treatment is well known to enhance seed performance, including germination, but sometimes reduces seed storability or longevity as a side effect. Toward developing a novel priming technique that can maintain seed longevity for a longer time period, chemicals that suppress the seed deterioration under a controlled condition were screened from 80 known biologically active compounds contained in the RIKEN NPDepo authentic library using Arabidopsis thaliana seeds. Seeds primed with mimosine, a cell cycle inhibitor, retained higher survival rate after a controlled deterioration treatment compared to seeds primed without the chemical. In addition, other cell cycle inhibitors such as aphidicolin, hydroxyurea and oryzalin had similar effects on the seed storability after priming. Our results suggest that progression of the cell cycle during priming is an important checkpoint that determines the storability of seeds after the treatment.