01482naa a2200193 a 450000100080000000500110000800800410001902200140006002400390007410000190011324501040013226000090023652009070024565000100115265000180116265000160118070000190119677300730121520767762017-10-05       2017    bl uuuu     u00u1 u    #d  a0190-41677 a10.1080/01904167.2016.12624012DOI1 aBALIGAR, V. C.  aInfluence of nitrogen forms and levels on the growth and nutrition of cacao.h[electronic resource]  c2017  aAmmonium and nitrate are the major forms of nitrogen (N) present in tropical soils. An experiment was conducted to assess the influence of nitrate and ammonium forms (N03-, NH4+, and mix of N03- + NH4+), and levels (1.5-12.0 mM) of N on the growth and nutrition of cacao (Theobroma cacao L). Growth parameters were significantly influenced by N forms, and nitrogen supplied as NH4+ proved better for the growth of cacao compared with N03- form and mixtures of these two forms. Irrespective of the forms of N, levels of N had no significant effect on plant growth parameters. Nutrient efficiency ratios (NERs)(shoot dry matter produced per unit of nutrient uptake) for macronutrients were sulfur» phosphorus» calcium&gt magnesium&gt nitrogen &gt potassium (S&gtp&gt Ca» Mg&gt N&gt K) and for micronutrients NERs were in the order of copper» boron» zinc» ironc- manganese (Cu» B&gt Zn&gt Fe&gtMn).  aCacau  aMicroelemento  aNitrogênio1 aFAGERIA, N. K.  tJournal of Plant Nutrition, New Yorkgv. 40, n. 5, p. 709-718, 2017.