Assessment of Phenotypic Variation of Arum Species in Jordan

Twenty-one locations scattered over eight provinces in Jordan were surveyed to assess the ecogeographical distribution of wild Arum species. Twenty-six morphological traits were measured on the collected species and populations to study the phenotypic diversities among and within species. Based on mean and standard deviation values, the highest variations were recorded for plant height, plant span, corm weight, spathe length, spadix length, leaf length and leaf mid-vein characters. Canonical discriminant analysis showed that leaf waxiness, spadix colour, spathe colour, leaf length, leaf width, plant span and leaf mid-vein are the main descriptors that can be used to differentiate among Arum species. Based on Euclidean distance coefficient, morphological characters showed a significant separation between Arum species with a similarity of 90.28% between A. palaestinum and A. dioscoridis, 74.90% between A. hygrophilum and A. dioscoridis and 82.18% between A. palaestinum and A. hygrophilum. The overall similarity analysis showed that the coefficient of similarity 81.40% was recorded among species over locations and 74.17% for species and locations combination. The results showed that Arum populations belonging to the same species are grouped in the same clusters regardless of collection site. In addition to the conservation of collected accessions in an operational gene bank, it is recommended to promote also the in situ conservation of Arum species