Predicting 2,4-Dichlorophenoxyacetic Acid Ester Transformation Rates in Periphyton-Dominated Ecosystems

Predicting 2,4-dichlorophenoxyacetic Acid ester transformation rates in periphyton-dominated ecosystems.

Using batch cultures, we determined transformation rate coefficients for microbial transformation of 2,4-dichlorophenoxyacetic acid butoxyethyl ester (2,4-DBE) in periphyton-dominated ecosystems. Rates of 2,4-DBE loss were measured over short periods of time (usually less than 10 h), and first-order transformation rate coefficients (k(1)) were determined under the specific conditions of low 2,4...

Pleistocene graminoid-dominated ecosystems in the Arctic

We review evidence obtained from analyses of multiple proxies (floristics, mammal remains, paleoinsects, pollen, macrofossils, plant cuticles, phytoliths, stable isotopes, and modeling) that elucidate the composition and character of the graminoid-dominated ecosystems of the Pleistocene Arctic. The past thirty years have seen a renewed interest in this now-extinct biome, sometimes referred to a...

Industrial toxicology; 2,4-dichlorophenoxyacetic acid.

Synergistic effects of copper and butylic ester of 2,4-Dichlorophenoxyacetic acid (Esternon Ultra) on amphibian embryos.

Cu2+ and butylic ester of 2,4-Dichlorophenoxyacetic acid as Esternon Ultra (2,4-D) toxicity on Bufo arenarum embryos were evaluated by means of a short-term chronic toxicity test (AMPHITOX). The NOEC values for Cu and 2,4-D were 0.02 mg/L and 2 mg/L respectively. The toxicity profile curves for Cu and 2,4-D were reported. The interactions of the metal and the herbicide were evaluated by combine...

Metabolism of 2,4-dichlorophenoxyacetic Acid in 2,4-dichlorophenoxyacetic Acid-resistant soybean callus tissue.

Three 2,4-dichlorophenoxyacetic acid (2,4-D) -resistant root callus tissue lines of Glycine max L. Merrill var. Acme were derived by culturing callus tissue 2 to 6 months on 40 milligrams per liter 2,4-D and designated 40R, 40B, and 40C. Tissue line 40R had a lower level of 2,4-D uptake in 2-week-old tissue which disappeared in 3.5-week-old tissue and less free 2,4-D following incubation for 24...