The Effect of Increasing Doses of Heavy Metals on Seed Germination of Selected Ornamental Plant Species

The primary goal of this study was to assess how two techniques for applying progressively higher doses of zinc and cadmium impact seed germination of selected ornamental plant species. The experiments were conducted in the accredited laboratory of the W. Legutko Breeding and Seed Company in Jutrosin, along with the Department of Plant Physiology at Poznań University of Life Sciences. Seeds from two ornamental species, Eschscholzia californica Cham. and Coreopsis lanceolata, were utilized. Two methods were used to treat the seeds with heavy metal solutions, involving four distinct two-factor experiments, each comprising eight combinations. This methodology adhered to the current ISTA guidelines. Germination energy was assessed after 7 days, while germination capacity was measured after 14 days. The two methods exhibited different effects on germination capacity and energy. The technique for treating seeds with heavy metal solutions and the duration of exposure to the metals play a significant role in germination. Soaking Eschscholzia californica Cham. seeds in increasing doses of zinc and cadmium solutions for 10 min before sowing showed no significant effect on their energy or germination capacity. Likewise, soaking Coreopsis lanceolata seeds in zinc solutions for 10 min before sowing did not significantly influence their energy and germination capacity. However, soaking Coreopsis lanceolata seeds in cadmium solutions for 10 min before sowing did not notably affect their germination capacity but significantly diminished their germination energy. Extended exposure of seeds placed on blotting paper soaked in cadmium sulfate and zinc sulfate solutions across all concentrations reduced energy and germination capacity for Eschscholzia californica Cham. and Coreopsis lanceolata seeds.