NITROGEN FERTILIZATION: YIELD, PRODUCTIVITY AND GAS EXCHANGES OF SOYBEANS CULTIVATED IN GREEN HOUSE
Glycine max; grains, production, nutrition
The earliest reports of domestication of the soybean crop (Glycine max (L.)) occurred in East Asia, in northeastern China. Among the essential elements required by plants, nitrogen is the one with the greatest effect on growth, responsible for root development, is part of the plant of the chlorophyll molecule, constituent of amino acids, proteins, enzymes, coenzymes and nucleotides. The objective of this work was to evaluate the effect of nitrogen on the components of production, productivity and gas exchange of the soybean cultivated in a clay latosol with a clay texture. The soil used to conduct the experiment was collected from the 0-20cm layer of the municipality of Paragominas. PAN. The cultivar used was M8644. Five nitrogen doses were used, corresponding to 0,0, 25, 50, 75, 100 mg N dm-3, associated to foliar nitrogen fertilization. The following parameters were analyzed: number of pods per plant, number of grains per pod, number of grains per plant, weight of 100 grains and productivity and number of nodules per plant, photosynthesis, transpiration, stomatal conductance, intrinsic efficiency of water use , instant water use efficiency, and concentration of macro and micronutrients in the leaves. The variables analyzed presented statistically significant results. It is possible to conclude that the combination between the nitrogen rates and the application of N through the leaf influenced significantly to the variables of production and productivity analyzed, in this way, it becomes feasible the application of nitrogen to leaf in the soybean plants.