Opium poppy(Papaver somniferum) is known as a plant synthesizing morphine, codeine and a variety of other benzylisoquinoline alkaloids as secondary metabolites, which are of pharmaceutical importance due to their narcotic and analgesic activities. But as cells induced from this plant lose their ability to produce morphinans, there have been few reports on suspended cell cultures to produce these morphinan alkaloids including thebaine, codeine and morphine, etc. Traditionally various kinds of elicitors was treated to enhance the accumulation of secondary metabolites in plant cell and organ cultures. Elicitors, however, usually have been treated to increase the secondary metabolite production not by whole plants in fields but by plant cells or tissues cultured in-vitro. We regarded elicitation as a useful tool to increase the morphinan compounds produced by intact plants, and to apply it to real farming of various medicinal plants in fields, several elicitors were treated to intact plantlets of P. somniferum and whole plants. Suspended cell and hairy root cultures as well as intact plants showed different metabolite production profiles, and different responses upon elicitation. To investigate biosynthetic pathway of morphinan alkaloids upon elicitation, protein expressions and mRNA levels of some key enzymes on the pathway such as berberine bridge enzyme (BBE), (7S)-salutaridinol 7-O-acetyltransferase (SAT) and codeinone reductase (COR) were quantified by western blotting and real-time PCR analysis.