02418naa a2200313 a 450000100080000000500110000800800410001910000220006024501570008226000090023952015340024865000170178265000200179965000140181965000110183365000170184465000100186165000160187165000230188765000130191065300110192365300120193465300100194665300200195670000140197670000170199070000220200777300750202914760972018-06-12       1996    bl uuuu     u00u1 u    #d1 aPURCINO, A. A. C.  aInfluence of Azospirillum inoculation and nitrogen supply on grain yield, and carbonband nitrogen-assimilating enzymes in maize.h[electronic resource]  c1996  aNitrogen (N) supply increased yield, leaf % N at 10 days after silking (DAS) and at harvesting, the contents of ribulose-1,5-bisphosphate carboxylase (RUBISCO) and soluble protein, and the activities of phosphoenolpyruvate carboxylase (PEPC), and ferredoxin-glutamate synthase (fd-GOGAT), but not of glutamine synthetase (GS) for six tropical maize (Zea mays L.) cultivars. Compared to plants fertilized with 10 kg N/ha, plants inoculated with a mixture of Azospirillum sp. (strains Sp 82, Sp 242, and Sp Eng-501) had increased grain % protein, and leaf % N at 10 DAS and at harvest, but not grain yield. Compared to plants fertilized with either 60 or 180 kg N/ha, Azospirillum inoculated plants yielded significantly less, and except for GS activity, which was not influenced by N supply, had lower values for leaf % N at 10 DAS and at harvest, for contents of soluble protein and RUBISCO, and for the activities of PEPC and fd-GOGAT. Yield was positively correlated to leaf % N both at 10 DAS and at harvest to the contents of soluble protein and RUBISCO, and to the activities of PEPC and Fd-GOGAT, but not of GS, when RUBISCO contents and enzyme activities were calculated per g fresh weight/min. However, when enzyme contents and enzyme activities were expressed per mg soluble protein/min, yield was correlated positively to RUBISCO and PEPC, but negatively to GS. These results give syupport to the hypothesis that RUBISCO, fd-GOGAT, and PEPC may be used as biochemical markers for the development of genotypes with (...)  aAzospirillum  aplant nutrition  aBactéria  aEnzima  aInoculação  aMilho  aNitrogênio  aNutrição Vegetal  aZea Mays  aEnzyme  aFixacao  aMaize  aNitrogen fixing1 aPAIVA, E.1 aSILVA, M. R.1 aANDRADE, S. R. M.  tJournal of Plant Nutrition, New Yorkgv. 19, n. 7, p. 1045-1060, 1996.