Notes from the Apothecary: Petunias   Petunias: Both a beautiful garden flower and a star of the RNA-focused scientific community. Way back in the 1990s, scientists tried to create deep purple petunias by inserting the gene associated with this colour. Instead, the flowers just came out white! Further studies into this led to big discoveries concerning RNA interference and gene silencing, for which scientists Andrew Fire and Craig Mello received the Nobel Prize in Physiology or Medicine. But it all started with the petunias. Petunia is not a single species, but a genus of flowers that contains around 35 distinct species. They’re all in the Solanaceae family, which also includes…