Abstract
A filed experiment was carried out under the conditions of the field of Crops Science Department. College of Agric and Forestry, University of Mosul in the season of 2011. The aim of the present study is to estimate the contamination of herbicides with water and to calculate the amount of herbicides absorbed by waterhyacinth plants. Three herbicides were selected for this experiment ,1. the plants treated with different doses of herbicides (Glyphosate and 2,4-D with two doses (2,4 L/ha) and Paraquat with dose of (1,2 L/ha) , 2. times of application (before and after flowering and 3. two methods of application (spraying and rope) .The experiments was set out as a randomized complete block design with three replicates .The results obtained from this study revealed that all herbicide led to a significant increases in the amount of herbicide contaminated with water when the herbicide sprayed on the vegetative parts , as well as it is noticed that the amount of herbicide contaminated with water was higher when the herbicide applied before the flowering stage as compound with plant sprayed after the flowering stage . It was observed that the amount of glyphosate and 2,4-D herbicides absorbed by plants were much more higher (i.e. 4-6 times) than that one observed by glyphosate herbicide.
