|
Journal of Aquatic Plant Management The Aquatic Plant Management Society
If you came to this page through the search function, use the browser back button to return to the search results. |
|
Volume |
40, 2002 |
|
Issue |
2 |
|
Page |
68 |
|
|
|
|
Title |
Activity of Endothall on Hydrilla |
|
|
|
|
Author(s) |
Gregory E. MacDonald, R. Querns, D.G. Shilling, S.K. McDonald and T.A. Bewick |
|
|
|
|
Keywords |
Hydrilla verticillata, herbicides, dinoseb, simazine, diuron, gramicidin, diquat, mode-of-action, conductivity, photosynthesis inhibition, uncoupler, ionophore |
|
|
|
|
Abstract |
Endothall was compared to compounds with known mechanisms-of-action in an attempt to elucidate its mode-of-action on hydrilla (Hydrilla verticillata [L.f.] Royle). In measurements of ion leakage over time, endothall caused 30% greater cellular damage in darkness than in light after 30 hours of exposure. Endothall did not affect chlorophyll fluorescence but inhibited photosynthetic oxygen evolution of hydrilla shoots after 2 hours. Endothall reduced respiration at 100 µM but stimulated respiration at 1000 µM. In comparative studies of phytotoxicity, the effects of endothall most closely resembled those of the ionophore, gramicidin or the uncoupler, dinoseb. This suggests the activity of endothall in hydrilla is membrane associated, possibly through the inhibition of ATP production in photosynthesis and respiration. The cessation of ATP production would cause a loss of cell membrane integrity, which more accurately explains the rapid, contact-type symptomology associated with endothall activity on hydrilla. |