Phenotypic diversity and morphological characterization of Amygdalus L. species in Lebanon

In this paper, we report on morphological diversity of Amygdalus L. species native to Lebanon, following a countrywide survey of almond germplasm wher eby a total of 149 accessions were collected throughout the country and cha racterized by thirteen quantitative and four qualitative traits. The result s indicated that the genetic diversity of Amygdalus communis L., Amygdalus korshinskyi Hand.-Mazz., and Amygdalus orientalis Duh. in Lebanon is high. Principal component analysis revealed that nut weight, nut volume, nut widt h, kernel volume and shell strength had highest loading in the first compon ent that accounted for 38.7% and 46.7% of total variation in A. communis an d A. orientalis, respectively. In contrast, leaf traits were present in the second component which accounted for 18% and 23.2% of total variation in e ach species, respectively. No significant correlations were detected betwee n leaf parameters and fruit traits in both species. The results indicated t hat quantitative leaf characters for all three species were determined by r ainfall and not altitude whereby adjacent accessions located in drier areas had smaller leaf sizes than those located in more humid regions. Quantitat ive fruit characters did not seem to vary accordingly. Qualitative leaf tra its in all three species reflected a variability which was independent of r ainfall. A. communis populations showed high variability, suggesting that t hey could be a valuable source in almond improvement programs.