02478naa a2200313 a 450000100080000000500110000800800410001902000180006010000190007824500890009726000090018630000140019550001480020952013690035765000150172665000140174165000110175565000120176665000170177865000250179565000140182065000090183465000160184365300090185965300220186865300100189070000190190077302450191912064752004-04-01       1997    bl uuuu     u00u1 u    #d  a85-86504-01-71 aBALIGAR, V. C.  aNutrient use efficiency in acid soilsbnutrient management and plant use efficiency.  c1997  ap. 75-95.  aProceedings of the Fourth International Symposium on Plant-Soil Interactions at low pH, Belo Horizonte, Minas Gerais, Brazil, 17-24 March 1996.  aAcid soils occupy about 30% (3.95 b ha) of the world's ice-free land area. Plant growth-limiting factors in acid soils include deficiences (N, P Ca, Mg, Mo, Zn) and toxicities (Al, Mn, Fe, H) of elements. The effciency of added fertilizers (N, P, K) is very low in acid soils. The integrated plant nutrient management system is important to improve crop yield potentials in acid, infertile soils. Genetic and physiological components of plants have profound effects on the ability of plants to acquire, transport, and utilize absorbed nutrients. To enhance dry matter yield (grain/forage) potentials for plants grown in acid soils, increases in nutrient use efficiency parameters (acquisition, influx, transport, utilization, remobilization) and plant growth parameters (plant demand, root morphology), and the ability of plants to interact effectively with environmental variables (drought, solar radiation, high temperature) are needed. Selection for efficient essencial nutrient acquisition and utilization and avoidance of ion toxicities (Al, Mn) appears to be a dominant approach to adapting plants to unfavorable acid soil environments. Cultural practices such as appropriate crop rotations, improvement of organic matter content in soil, and control of soil erosion, insects, diseases, and weeds can improve crop yields and optimize nutrient use efficiency.  aacid soils  anutrients  aÁcido  aCerrado  aDeficiência  aDeficiência do Solo  aNutriente  aSolo  aSolo Ácido  aAcid  aSoil deficiencies  aSoils1 aFAGERIA, N. K.  tIn: MONIZ, A. C.; FURLANI, A. M. C.; SCHAFFERT, R. E.; FAGERIA, N. K.; ROSOLEM, C. A.; CANTARELLA, H. (Ed.). Plant-soil interactions at low pH: sustainable agriculture and forestry production. Campinas: Brazilian Soil Science Society, 1997.