Assessment of morphological variability of leaves and fruits of three natural populations of wild caper (Capparis spinosa L.) in western Algeria

Capparis spinosa L., family Capparidaceae, is a spontaneous plant of great economic, medicinal and ecological importance. This study focused on the estimation of morphological variability of three populations of the spiny caper from western Algeria by measuring morphological traits of leaves, fruits and seeds. Variance analysis showed that there were significant (P<0.05) difference (number of seeds per fruit) to highly significant (P<0.001) difference (the other morphological traits) between the three spontaneous caper natural populations with coefficients of variation ranging from 6.39% to 24.11%. There were no interpopulation differences for fruit width (P>0.05). The populations of Taghit (Bechar) and Sidi Belattar (Mostaganem) showed the best morphological traits. The population from Taghit had the best means for leaf length (35.62±3.47 mm), fruit width (35.62±3.47 mm), fruit weight (11.06±2.74 g), peduncle length (79.55±12.26 mm) and number of seeds per fruit (157±40.20). The population from Sidi Belattar was characterized by the highest leaf widths (39.24±3.89 mm), petiole lengths (11.309±2.02 mm), fruit lengths (42.433±4.15 mm), seed lengths (3.46±0.20 mm) and thousand seed weights (12.15±1.75 g). While the population from Mghila (Tiaret) had the lowest means for most morphological traits. Principal component analysis (PCA) showed a geographical separation between the studied populations with a polymorphism of 83.31%. The hierarchical classification using Ward’s distance classified the populations into two clusters related to climatic and edaphic gradients.