Occurrence of nudicaulin structural variants in flowers of papaveraceous species

Nudicaulins, a unique group of indole alkaloids, are responsible for the petal color of three yellow-blooming papaveraceous species, Papaver nudicaule, Papaver alpinum and Meconopsis cambrica. The petal color of orange cultivars of P. nudicaule and P. alpinum is conferred by the co-occurrence of nudicaulins with pelargonidin derivatives and the petal color of a red P. nudicaule cultivar is due to pelargonidins alone. Two acylated nudicaulins have been found in M. cambrica.