Inter-relation between descriptors and morphine yield in Asian germplasm of opium poppy Papaver somniferum

A set of 208 Indian and two Thai germplasm accessions of opium poppy Papave r somniferum were assessed for variation in 17 morphological characters, se ed yield and content and yield of morphine from capsules and peduncles. The germplasm was found to be highly variable for all the characters evaluated . In the harvested peduncles and capsules, 13% was peduncle straw, 61% seed s and the rest capsule husk. The peduncle and capsule straw yields ranged b etween 0.6-2.2 and 1.4-5.3 g plant(-1), respectively. Morphine content in t he peduncle varied between about 0.001-0.24% and that in the capsule from 0 .02 to 1.05%. On average basis morphine content in the capsule husk was mor e than 9-fold higher than the peduncle straw. The plant morphine yields fro m peduncles and capsules ranged between 1.2 and 28.6 mg plant(-1). Four acc essions yielded more than 20 mg of morphine plant(-1). Among these, in one of the accessions about 13% of the morphine was contributed by the peduncle . The plants of high morphine yielding accessions were generally small in h eight, and bore white flowers and large sized ungrooved capsules with a sma ll number of seeds, on a large peduncle.