51动漫

Blooming cold

FLOWERS have long memories. They can remember the long chill of winter, presetting their genes for flowering months later.

A team led by Caroline Dean at the John Innes Centre in Norwich have worked out how. When a young plant first experiences cold, the chill switches off a gene called FLC that blocks flowering. 鈥淚f some plants don鈥檛 experience cold, they simply won鈥檛 flower,鈥 says team member Gordon Simpson.

But the plant doesn鈥檛 grow flowers straight away. Instead, a second gene called VRN2 keeps FLC in the 鈥渙ff position鈥, maintaining the memory of the cold while non-flowering parts of the plant mature.

It鈥檚 not until the warmer, longer days of spring arrive that the plant capitalises on the deactivated FLC gene by starting to grow flowers.