2018-03-212018-03-212015-03FAGERIA, Nand Kumar; FERREIRA, Enderson Petrônio De Brito; KNUPP, Adriano Moreira. Micronutrients use efficiency in tropical cover crops as influenced by phosphorus fertilization. Revista Caatinga, Mossoró, v. 28, n. 1, p. 130-137, Jan./Mar. 2015.0100-316Xe- 1983-2125http://repositorio.bc.ufg.br/handle/ri/14108Deficiency of micronutrients is increasing in the recent years in cropping systems in many parts of the world and cover crops are important components of cropping systems. A greenhouse experiment was conducted to evaluate copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) use efficiency in 14 tropical leg- ume cover crops grown on an Oxisol. The P levels used were low (0 mg kg -1 ), medium (100 mg kg -1 ) and high (200 mg kg -1 ). The P X cover crops interactions were significant for Cu, Fe, Mn, and Zn use efficiency (tops dry weight/unit nutrient uptake). Hence, cover crop species varied in nutrient use efficiency with change in P levels. The micronutrient use efficiency was in the order of Cu > Zn > Mn > Fe. Higher Cu use efficiency was associated with lower uptake of this element, in the cover crop tops compared to other micronutrients. Similar- ly, lower efficiency of Fe and Mn was associated with their higher uptake in the tops of cover crops. Overall, Cu and Mn use efficiency was decreased when P level was raised from low to medium level and then it was constant. Iron use efficiency was increased with increasing P level but Zn use efficiency was constant with the addition of P fertilizer.engAcesso AbertoGreen manureCrotalariaMucunaCajanusAdubo verdeCrotaláriaMucunaGuandúArtigo