Abstract: Fertilizers containing urea with urease inhibitors, wherein the urease inhibitors are bromo-nitro compounds having the formula: ##STR1## wherein A.sub.1 is (CH.sub.2).sub.n.sbsb.1 X.sub.1, and A.sub.2 is (CH.sub.2).sub.n.sbsb.2 X.sub.2, wherein both n.sub.1 and n.sub.2 and X.sub.1 and X.sub.2 are the same or different, the alkyl groups of A.sub.1 and A.sub.2 are straigh-chain or branched-chain alkyl groups, and the substituents X.sub.1 and X.sub.2 are attached to any one of the carbon atoms of the alkyl groups, and n.sub.1 and n.sub.2 are 0 to 6, X.sub.1 and X.sub.2 are H or YR, wherein Y is --O--, --S-- or --NH-- and R is H or a straight or branched chain C.sub.1 -C.sub.6 alkyl, cyclopent(en)yl cyclohex(en)yl or phenyl group having one to three methyl groups or ##STR2## attached thereto, and R.sub.1 is H or a straight or branched chain C.sub.1 -C.sub.6 alkyl, cyclopent(en)yl or cyclohex(en)yl group having one to three methyl groups or ##STR3## attached thereto.

Abstract: A fertilizer concentrate composition comprising (1) 80-90%, by weight, of water-soluble salts of plant micronutrients, 10-18 mole percent of said salts being in complexed form, and (2) 0.7-1.75%, by weight, of a stabilizer comprising a solid, water-soluble polymer in powder form having a particle size such that 80-90% by weight, of said particles have a diameter <0.1 mm and less than 0.5 percent, by weight, of said particles have a diameter >0.5 mm, (3) balance, complexing agent for said micronutrients, with the proviso that the amount of complexing agent is chosen so that 10-18 mole percent of the micronutrients are complexed and, optionally, (4) 0.05-0.5%, by weight, of a surfactant, provides a storage-stable, readily soluble micronutrient concentrate usable especially in fertilizing crops by leaf dressing.