Mating system analysis of Spanish argan [Argania spinosa (L.) Skeels] accessions in-situ and ex-situ conserved by using SSR markers

Abstract The argan tree [Argania spinosa (L.) Skeels] is a multipurpose species endemic of Morocco. It has been mainly characterized as a self-incompatible (SI) species. Argan trees are also found in Murcia, a region located in Southeaster Spain, where they are currently yielding viable fruits and seeds in an isolated environment. This study investigated the self-compatibility (SC) of these Spanish argan accessions. This was done through in-situ research and characterization of isolated argan trees in open pollination settings. Addi-tionally, the seedlings from these trees were characterized using (Simple Sequence Repeat) SSR markers. In addition, the ex-situ study of the collection of Spanish argan accessions from the CEBAS-CSIC (Centro de Edafología y Biología Aplicada del Segura-Consejo Superior de Investigaciones Científicas) in Murcia, have also be characterized in open polli-nation conditions and by bagging argan accessions to evaluate fruit set in absence of pollinator also analysing the obtained seedlings by SSRs. As expected, in the analysis of in-situ conserved argan accessions, the isolated trees showed a suitable flowering intensity during the two years evaluated. However, while the Spanish argan accessions isolated from ‘Cartagena’ and ‘Mazarrón’ showed fruits, the accessions from ‘Molina de Segura’ and ‘Ojos’ showed a null fruit set in both years. In the case of bagging of these ex-situ con-served accessions, results showed that in the absence of natural pollinators of argan (especially flies), a certain level of fruiting is observed in bagged branches in some specimens. First results showed then that self-fertilization is possible in some argan accessions and that fruits are obtained without pollen from other accessions. If self-compatibility accessions are confirmed in Spain or Morocco, they are very useful for basic research in breeding programmes.