Herbicides are the most widely used of chemical pesticides for agricultural production and landscape management. The environmental risk of herbicides should be evaluated near sites of application, even though basic ecotoxicological tests have been conducted before they can be registered for marketing. For example, triazine herbicides, which are photosynthetic PSII herbicide that considered only slightly or moderately toxic to many susceptible plants, soil microorganisms, mammals and humans,

more »

... ver, concerns have arisen because this herbicide are members of a class claimed to be carcinogenic, or may affect the development as reproductive toxins. For this reason, most reliable evidence is needed to test these claims and investigate their ecological effects. Prometryn is a herbicide belongs to triazine family that may leave residual activity in the soil for extended periods, causing injury and yield reduction of susceptible soil microorganisms and crops in rotation. Compared with other methods, the rapidity of response, sensitivity, high level of precision, simple process and easy operation are the advantages of bioassay methods for the routine monitoring of biologically available photosynthesis-inhibiting herbicides present in agricultural soils. Materials and Methods: A pot experiment was conducted under greenhouse conditions in order to study the sensitivity of 4 different crops to prometryn soil residue at the College of Agricultural Sciences, Ilam University, Ilam, Iran in 2014. Experimental type was completely randomized design in a factorial arrangement with three replications. Treatments included 4 different crops (lettuce, barley, rapeseed and beet) and prometryn simulated concentrations residues in soil (0.0033, 0.0166, 0.033, 0.066, 0.1 and 0.166 mg. kg-1soil). 15 cm diameter pots were filled with a modified soil and 10 of seeds of crops were planted in 5 regular positions. The plants were thinned to five plants per pot after germination. The pots were kept for 30 days under controlled cond [...]