Study on the herbicidal activity of vulculic acid from Nimbya alternantherae

摘要

The detached leaves of 28 species of plants and the plants of alligator weed were tested for toxic activity of vulculic acid isolated from Nimbya alternantherae. Results indicated that the toxin was non-host-specific and could cause leaf blight and withering of alligator weed. The effect of the toxin on the ultrastructure of leaf tissue of alligator weed was studied by treating the mature leaves with the toxin. It was shown that the damage on leaf tissue included plasmolysis and vacuolation in cells,lamellae disorder and vacuolation in chloroplasts as well as disappearance of ridges and vacuolation in mitochondria after treatment with vulculic acid at a concentration of 50 mu g/ml for 12 h. These results suggest that the target sites for vulculic acid action may be the plasma membranes, the lamellae of chloroplast and the ridges of mitochondria of the alligator weed leaf.