Autotoxic effects of Chrysanthemum (Chrysanthemum morifolium (Ramat) Tzvel.)

We evaluated the autotoxic effects of aqueous extracts of leaves, stem, root, rhizosphere soil, litter and root exudates from field grown chrysanthemum on the seed germination and seedling growth of the same plant specie. The aqueous extracts, from above-ground parts were highly autotoxic to seed germination and seedling growth and autotoxicity increased with the increasing concentrations. The aqueous extracts inhibited the enzymatic activities of isocitrate dehydrogenase (IDH) in roots and nitrate reductase (NR) in leaves and significantly stimulated the formation of malonylodialdehyde (MDA) in leaves. We conclude that autotoxicity observed in laboratory conditions was partly responsible for negative effects observed in field or greenhouse, or for problem of continuous cropping of chrysanthemum.