Seed germination responses of the Saharan plant species Ephedra alata ssp. alenda to fungicide seed treatments in the laboratory and the field
Résumé
Given its importance in the functioning of arid ecosystems, Ephedra alata ssp. alenda has drawn some attention and appeared to be suitable for desert re-vegetation. An experimental study has been carried out on the germination properties of seeds of this strictly Saharan species. Analyses of temperature effects, and fungicide seed treatments in the laboratory and the field enabled to determine the optimum germination conditions. The predominant microorganisms isolated from the E. alata ssp. alenda seeds before treatment were Alternaria alternata and Rhizopus spp. The germination capacity was significantly greater between 20 and 25 °C. Captab (61.1 %) and propiconazole (53.2%) fungicides significantly increased the germination of E. alata seeds. These results are confirmed by experiments in the field where all treatments (except treatments with NaOCl and benomyl) significantly increased the emergence percentage. None of the treatments (except benomyl) affected the shoot and root length of the plants. Benomyl treatment resulted in a significant decrease in the shoot and root length.