Mineral Nutrition and Morphine Production in Papaver somniferum

Mineral nutrition of poppy (Paparer somniferum L.) was studied in its effects on morphine production. Hydroponic cultures were carried out with nutritive solutions percolating over sand. The anion NO_3- is the most efficient form of nitrogen for the production of fresh matter, dry matter or total morphine; in the latter respect, it rates higher than the NH₄NO₃ form which, on the other hand, gives higher alkaloid contents, while both cation NH₄⁺ and urea have depressive effects. Phosphates have apparently little effect on the growth of the poppy, but solutions enriched with assimilable phosphate do stimulate flower proliferation and fruit development, without increasing markedly the total morphine output. Mg²⁺ and Ca²⁺ are important factors; Mg deficiencies will bring about a marked elongation of stems and early flowering, without any notable decrease in morphine outputs; conversely, Ca deficiencies will cause a drop in alkaloid production, while more calcium in the solution will give stronger elongation, a larger number of capsules and a marked increase in the weight of dry matter and morphine outputs, without any marked change in content. Sodium will favour poppy development (flowers and capsules) and will increase both the content and output of morphine. Na⁺ should therefore be introduced whenever possible in the fertilizing of poppy crops.