as ammonium nitrate urea and the like the concentration of the active ingredients in the synergistic composition of the present invention is generally from 0 001 to 98 percent by weight concentrations from 0 01 to 90 percent by weight are often employed in compositions designed to be employed as concentrates the active ingredients are generally present in a concentration from 1 to 98 weight percent preferably 5 to 90 weight percent such compositions are typically diluted with an inert carrier such as water before application or applied as a dry or liquid formulation directly into flooded rice fields the diluted compositions usually applied to weeds or the locus of weeds generally contain 0 0001 to 10 weight percent active ingredient and preferably contain 0 001 to 5 0 weight percent the present compositions can be applied to weeds or their locus by the use of conventional ground or aerial dusters sprayers and granule applicators by addition to irrigation or paddy water and by other conventional means known to those skilled in the art seeds of the desired test plant species were planted in 80 mineral soil 20 grit planting mixture which typically has a ph of 7 2 and an organic matter content of about 2 9 percent in plastic pots with a surface area of 128 square centimeters cm 2 the growing medium was steam sterilized the plants were grown for 7 19 days in a greenhouse with an approximate 14 hour h photoperiod which was maintained at about 29 u00b0 c during the day and 26 u00b0 c during the night nutrients and water were added on a regular basis and supplemental lighting was provided with overhead metal.