Morphine Biosynthesis in Opium Poppy Involves Two Cell Types: Sieve Elements and Laticifers Onoyovwe, Akpevwe ; Hagel, Jillian M. ; Chen, Xue ; Khan, Morgan F. ; Schriemer, David C. ; Facchini, Peter J. Abstract Publication: The Plant Cell Pub Date: October 2013 DOI: 10.1105/tpc.113.115113 Bibcode: 2013PlanC..25.4110O