EFFECT OF GENOTYPE ON ARGAN (ARGANIA SPINOSA L. SKEELS) NUTS GERMINATION IN THE EASTERN REGION OF MOROCCO

Abstract

The sustainability of Moroccan argan forests is nowadays threatened by drought, overexploitation and a natural regeneration rate that is very low, which requires the implementation of appropriate conservation and enhancement strategies. The objective of this study is to evaluate the inter-genotypic variability of argan tree nuts germination (Argania spinosa L. Skeels) in order to identify the germination performance of nuts from three argan tree varieties: Beni-Snassen, Chouihiya, Souhayl and a clone X currently under development. The results obtained reveal important differences between the genotypes tested: the Beni-Snassen variety recorded the highest germination rate (82.31%) with a reduced latency period (7 days).Then Chouihiya (81.83%), clone X (79.63%) and the Souhayl variety, which had the lowest germination capacity (65%) despite the larger size of its nuts. These threes genotypes were characterised by a latency period of (9 days). Also, the, analysis of seedlings from nuts containing more than one amond showed an increase in the number of seedlings produced per nut, accompanied by an increase in the germination rate. This improvement was particularly observable in clone X (89%) and the Souhayl variety (70.45%), attributable to the large size of the nuts containing more than one viable amond. In contrast, the Beni-Snassen (87%) and Chouihiya (85.55%) varieties showed only moderate improvement, probably due to the small size of the nuts, which limited the number of almonds. These results confirm that germination vigour and seedling production are determined more by the effect of the mother plant and nuts viability (embryonic viability and seed coat dormancy) than by nuts size. These results highlight the importance of rigorous selection of mother trees in seed orchards in order to identify the most productive genotypes, while ensuring that a wide genetic diversity is preserved.