Variations in seeds of three endemic leguminous species at different altitudes

Abstract

Seeds of three legumes, Adenocarpus decorticans. Astragalus granatensis ssp. granatensis and Cytisus reverchonii, endemic to the Betic Cordillera, were collected from different altitudes. Under laboratory conditions, various factors and endogenous characteristics which may affect their germination potential in the field were studied. The seeds of all three species required chemical scarification in order to germinate, and the maximum germination temperature of all three proved to be correspondingly higher the higher the altitude of their ecological niche. However, each species showed differences in germinability and optimum temperature according to altitude. Variations in free and bound abscisic acid (ABA) and proline, according to altitude, did not follow the same pattern in each species; they increased in Cytisus, fell in Adenocarpus, and remain unchanged in Astragalus. The highest germination rates were obtained when free‐ABA levels were lowest in all species. The polyamines, spermidine, spermine, putrescine and cadaverine, were present in all species, spermi‐dine being the most abundant. Putrescine was the only polyamine whose level varied with altitude, decreasing in Adenocarpus and Cytisus, and increasing in Astragalus.