Morphological and germination capacity of Argania spinosa’s (L) Skeels of Algeria South-West population: variability of fruit and stone morphotypes

Abstract

Aim of study: The purpose of our study is the highlighting of phenotypic variability within the natural population of Argania spinosa (L.) Skeels by morphological characterization of fruits and stones and by evaluation germination capacity of stones.Area of study: The Argan tree stand is located in southwest of Algeria (Tindouf).Material and Methods: The fruits were collected on a sample of 30 mother trees for three consecutive years. We carried out the morpho-biometric characterization (shapes, dimensions and weight) of thirty fruits and thirty stones from each mother-tree, and assessed the germination capacity of the different morphotypes.Main results: We found high variability of morphological characters of fruits and stones between trees. Five fruits shapes (oval, avoid, rounded, spherical and very spherical) and three different stones shapes (oval, avoid and spherical) were identified in mother-trees. The rounded, spherical and very spherical shapes of fruits are the most abundant (82%). High variability in the germination capacity of the different Argan tree genotypes and strong correlation were emphasised between capacity germination and stones shape and dimensions. Multivariate analysis showed that trees with small-sized, spherical stones showed better germination (98%) than trees with larger and elongated (oval) stones (51%). However, no significant difference was found between harvest years for any studied trait.Research highlights: Results of this research allows the selection of mother- trees to improve the production of seedlings in nursery, to successful regeneration and to ensure conservation and sustainable use of the genetic resources of this rare and endangered species.Keywords: Argania spinosa; variability; morphological; fruits; stones; germination capacity.