BENSULFURON METHYL ACTIVITY ON EURASIAN WATERMILFOIL

Citation
Ls. Nelson et al., BENSULFURON METHYL ACTIVITY ON EURASIAN WATERMILFOIL, Journal of aquatic plant management, 31, 1993, pp. 179-185
Citations number
20
Categorie Soggetti
Plant Sciences","Marine & Freshwater Biology
ISSN journal
01466623
Volume
31
Year of publication
1993
Pages
179 - 185
Database
ISI
SICI code
0146-6623(1993)31:<179:BMAOEW>2.0.ZU;2-X
Abstract
The efficacy of bensulfuron methyl (BSM) at 40 concentration and expos ure time combinations was evaluated on Eurasian watermilfoil (Myriophy llum spicatum L.) under controlled-environment conditions. BSM concent rations ranged from 0 to 4600 mu g/l; exposure times ranged from 7 to 42 days. Efficacy was based on shoot and root biomass harvested at the conclusion of each experiment. Herbicide injury was evident 1 week af ter application on all treatments, and symptoms included leaf chlorosi s, deformed leaves on shoot tips, downward bending of leaves at upper nodes, stem necrosis, and formation of axillary buds. Following 7-, 14 -, 21-, 28-, 35-, and 42-day exposure periods at concentrations rangin g from 10 to 4600 mu g/l, biomass was reduced 10 to 90% compared to un treated plants. Increasing exposure time was more efficacious than inc reasing concentration. BSM concentrations <10 mu g/l did not significa ntly reduce growth. Effects on roots were variable depending on concen tration and plant age. Only treatments of 230 mu g/l and higher inhibi ted root growth on plants grown for 3 weeks prior to treatment. Regrow th emerged from rootcrowns, axillary buds, and injured shoot apices, a nd was evident 1 to 2 weeks following completion of the exposure perio d and removal of the BSM-treated water. Plant death was not achieved a t the concentrations and exposure times tested in these studies.