Morphological and phytochemical diversities among Persian poppy (Papaver bracteatum) populations in Iran

Abstract

Persian poppy (Papaver bracteatum Lindl) is a precious medicinal plant found in limited regions of Iran. This plant possesses a significant amount of thebaine alkaloid, which can be easily converted into codeine. It can also be converted into Bentley compounds and several narcotic antagonists. This research aimed to investigate the morphological differences among nine Iranian populations of P. bracteatum in their natural habitats and compare them based on biochemical characteristics, such as thebaine content, amino acids, and fatty acids. The morphological variations were assessed using 30 quantitative traits. Analysis of variance revealed significant differences in 18 morphological characteristics among populations. The evaluation of thebaine content indicated that capsules consistently had higher thebaine content (3.7–9.3%) compared to roots (1.3–4.8%), stems (0.6–2.5%), and leaves (0.7–1%) in all populations, and the Rangeh-Rizhan population displayed the highest thebaine content (9.3 ± 0.12%) in capsules. Furthermore, 25 amino acids and four fatty acids were identified in leaves and were used as chemotaxonomic markers to distinguish between populations. Based on morphological and biochemical characteristics as well as combined datasets, five distinct clusters were created, each of which included two main groups and a few subgroups. However, populations inside the groups differed slightly in various clusters; Mahabad, Rangeh-Rizhan, and Janevareh populations were distinctly separated from others in clusters formed using morphological, fatty acids, and combined datasets. On the other hand, a clear-cut separation of the Polur population from the rest was evidenced in clusters created from thebaine and amino acids data. The principal coordinate analysis (PCoA) results were largely aligned with those of cluster analysis. This research revealed a high degree of morphological and phytochemical variations among P. bracteatum populations, which could provide new insights into the conservation and breeding of the Persian poppy populations.