EVOLUTIONARY SIGNIFICANCE OF AWN LENGTH VARIATION IN A CLONAL GRASS OF FIRE-PRONE SAVANNAS

摘要: We investigated the selective advantage of continuous variation awn length in clonal grass Hyparrhenia diplandra (Poaceae) a West African tropical savanna (Ivory Coast) that burns every year. This species is apomictic, so all seeds produced by one mother plant have same genotype. H. produces diaspores with hygroscopic whose varies within and among plants. In other species, awns play significant role secondary dispersal on ground seed burial. Using an experimental approach, we quantified (1) environmental genetic components variation, (2) influence burial depth, (3) effect germination seedling survival rates burned unburned plots, (4) potential fire intensity selecting different lengths. Awn varied from 35 to 70 mm was highly heritable (h2 = 0.63). Variation individuals not related flowering p...