Detection of DNA polymorphism in Papaver somniferum genotypes differing in straw morphinan alkaloid content

Thirty-two distinct accessions of Papaver somniferum were screened for morphinan alkaloid content in the straw. The combined content of major morphinan alkaloids (morphine+codeine+thebaine) was found to vary in the range 0.2260-0.0683%. Two genotypes each, were selected as prototypes for low [I-48 (0.0683%) and I-344 (0.0878%)] and high [Pps-1 (0.2260%) and N-3 (0.2074%)] morphinan alkaloid content for studying DNA polymorphism. RAPD analysis of these four genotypes using 80 primers could not detect the polymorphism. However, AFLP analysis of these genotypes with 12 EcoRI/MseI primer pairs could distinctly group the high- and low-morphinan alkaloid genotypes separately. Furthermore, 50 AFLP fragments, specific to high-straw morphinan alkaloid genotypes (Pps-1 and N-3) and 28 DNA fragments specific to low-straw morphinan alkaloid genotypes (I-48 and I-344) could be identified. This investigation is the first report on the polymorphism identified in the genotypes differing in their straw morphinan alkaloid content. This DNA polymorphism could be exploited for defining chemotypes at an early seedling stage in poppy breeding programmes.