Nitrogen fractions in the microbial biomass in soils of southern Brazil
Data(s) |
01/03/1999
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Resumo |
The reaction of nitrogen compounds with ninhydrin can be used as an indicator of cytoplasmic materials released from microbial cells killed by fumigation. Total-N, ninhydrin-reactive-N (NR-N), ammonium-N (A-N), and α-amino-N in the microbial biomass of soils from the State of Rio Grande do Sul, Brazil, were determined, in 1996, in 0.5 mol L-1 K2SO4 extracts of fumigated and non-fumigated soils. Total-N varied from 20.3 to 104.4 mg kg-1 and the ninhydrin-reactive-N corresponded, in average, to 27% of this. The ninhydrin-reactive-N was made up of 67% ammonium-N and 33% aminoacids with the amino group at the α-carbon position. It was concluded that colorimetric analysis of NR-N and A-N may be used as a direct measure of microbial N in soil. This simple and rapid procedure is adequate for routine analyses. |
Formato |
text/html |
Identificador |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06831999000100022 |
Idioma(s) |
en |
Publicador |
Sociedade Brasileira de Ciência do Solo |
Fonte |
Revista Brasileira de Ciência do Solo v.23 n.1 1999 |
Palavras-Chave | #Biomass-N #biomass ninhydrin-reactive-N #biomass ammonium-N #biomass α-amino-N |
Tipo |
journal article |