Micropropagation of zygotic embryos from genetically diverse almond seedling orchards in eastern Morocco

Numerous studies on perennial crops have shown that almond has a low tolerance to climate change, which led to detailed study for its adaptation by focusing on selecting heat-tolerant almond varieties. The long period of perennial agriculture creates particular challenges in a changing climate. The risk complicates the choice of a variety that the best variety for the current climate may be poorly suited for future climates. Hence the interest of having a large variability of tolerant genotypes. In the eastern Mediterranean region of Morocco, seedling almond trees are largely grown, which created an important gene pool, both for breeding programs and the selection of superior genotypes adapted to difficult pedo-climatic conditions. For the conservation of crop biodiversity in these almond groves, micropropagation is considered a feasible technique for producing and regenerating superior planting materials. Zygotic embryos of several local ecotypes of the almond native population known as ''Beldi'' were cultivated on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of auxins and cytokinins. The results showed multiple shoot initiation from zygotic embryos on MS medium containing 1mg/L of 6-Benzyl-aminopurine (BAP) combined with 0.5 mg/L of Indole butyric acid (IBA). A high rooting rate was obtained on a half-strength MS medium supplemented with 1mg/L of IBA.