30 June 2017
Vol 356, Issue 6345

About The Cover

Cover image expansion

COVER Adaxial surface of a petunia flower. Each night, volatile organic compounds are released from conically shaped epidermal cells of petunia flower petals. Volatile emission, once thought to be driven solely by diffusion, is dependent on active transport facilitated by ATP-binding cassette transporters. See pages 1334 and 1386
Photo: Tatiana Dorokhova/Alamy Stock Photo