Morphological characteristics and soil attributes of five species of Galium (Rubiaceae) from North Africa

The morphological variations between selected five Galium species from Libya, and the role of soil factors that affect their distribution in their natural habitats were investigated. Thirty - seven macromorphological characters (11quantitative, 26 qualitativ e) representing vegetative parts were subjected to numerical - taxonomic analysis. Five branches and clusters were distinguished; each was linked to a specific species. Representatives of these groups were clustered together according to characters with high factor loading in the Principal Components Analysis (PCA). The results showed congruence between the UPGMA clustering and PCA in suggesting five species groups. Seventeen soil factors were used in this assessment of soil factors responsible for the distri bution of the 5 species of Galium . Calcium and chloride ions content exhibited the most significant difference ( p= 0.05) among the five species groups, while the other examined soil variables showed no significant differences. The relationship between the e xamined soil variables and the studied populations of Galium species was assessed by Principal Components Analysis (PCA). Each of the studied species of Galium was affected by one or more of the examined soil parameters.