Population variability of weedy sunflower as invasive species

Abstract

Three populations of weedy sunflower were investigated with the aim to assess its population variability. The following parameters were evaluated: vegetative parameters - plant height (cm), leaf lenght (cm), leaf width (cm), number of ray flowers, number of bract; generative parameters - head diametar (cm), mass of achene per head (g), number of achene per head; and achene parameters - achene lenght (µm), achene width (µm), mass of 100 achenes (g). Except that, achene morphology as indicator of population variability was studied. The studied populations significantly differed regarding to most measured parameters, while only plant height and number of ray flowers were similar in all three populations.