Open AccessEvaluating Semiaquatic Herbaceous Perennials for Use in Herbicide Phytoremediation
Author(s) -
R. Thomas Fernandez,
Ted Whitwell,
Melissa B. Riley,
C. Bernard
Publication year - 1999
Publication title -
journal of the american society for horticultural science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.408
H-Index - 80
eISSN - 2327-9788
pISSN - 0003-1062
DOI - 10.21273/jashs.124.5.539
Subject(s) - oryzalin , perennial plant , biology , botany , photosynthesis , weed , canna , horticulture , herbaceous plant , ornamental plant , microtubule , biochemistry , starch , microbiology and biotechnology
Canna × generalis L.H. Bail. (canna) , Pontaderia cordata L. (pickerel weed), and Iris L. × `Charjoys Jan' (`Charjoys Jan' iris) were exposed to a 5 mg·L -1 suspension of isoxaben or oryzalin or a water control for 9 days. Growth and photosynthetic responses were monitored throughout treatment and for an additional 22 d after termination of treatment. By the end of the experiment plant height of pickerel weed was reduced by oryzalin. Isoxaben resulted in lower height and reduced leaf emergence for all three taxa by the end of the experiment. Leaf CO 2 assimilation (A) and transpiration (E) were lower for oryzalin-treated canna only 17 and 18 days after treatment, several days after treatment had been terminated. Leaf A and E were lower for oryzalin-treated pickerel weed and `Charjoys Jan' iris for most days after day 17. Isoxaben reduced A and E of all three plants for all days measured except day 6 for `Charjoys Jan' iris. Lower photosystem II efficiency (Fv/Fm) was found for isoxaben-treated canna from day 5 onward and days 7, 20, and 23 for pickerel weed and `Charjoys Jan' iris. Rapid reduction in A and Fv/Fm for all plants treated with isoxaben indicates a direct effect of isoxaben on photosynthesis. Reductions in growth and photosynthetic parameters due to oryzalin were minimal for all plants indicating these plants would be useful in phytoremediation systems where oryzalin is present. However, growth and photosynthetic parameters were reduced substantially for all plants exposed to isoxaben indicating the taxa studied would not perform well in phytoremediation systems with this level of isoxaben exposure. Chemical names used: isoxaben ( N -[3-(1-ethyl-1-methylpropyl)-5-isoxazolyly]-2,6-dimethoxybenzamide); oryzalin (4-(dipropylamino)-3,5-dinitrobenzenesulforamide).