Descomposición in vitro y contenido de nitrógeno en residuos de Nassella tenuis Bark. y Stipa ichu Kunth. inoculados y no inoculados

GIL, M. E.; FERNÁNDEZ, O. A.

Tafí del Valle, Tucumán

Jornada; XXIII Jornadas Científicas; 2006

Asociaición de Biología de Tucumán

IN VITRO DECOMPOSITION AND NITROGEN CONTENT IN NASSELLA TENUIS BARK. AND STIPA ICHU KUNTH. RESIDUES, INCUBATED WITH AND WITHOUT SOIL   GIL, M. E.; FERNÁNDEZ, O. A Departamento de Agronomía - CERZOS. Universidad Nacional del Sur. Altos del Palihue s/n, Bahía Blanca, Argentina. e-mail: megil@uns.edu.ar     The aim of this work was to evaluate the effect of inoculation with soil solution on the decomposition rate and nitrogen content of senescent roots and shoots of Nassella tenuis and Stipa ichu, two perennial Poaceae from Calden District, Argentina, incubated in vitro (25ºC). CO2 evolution was recorded daily, litter weight loss after 40 and 90 days incubation, and N content initially, and after both incubation times. Inoculated N. tenuis and S. ichu shoots, and S. ichu roots  presented the greater rate of CO2 release during the first 30 days incubation.  At the end of the experiment, none of the treatments (combination of species - plant part, inoculated vs. non inoculated) lost more than 8% of their initial dry weight. Inoculation only resulted in a higher dry weight loss in S. ichu roots, and it didn´t produce significant differences in N content between samples. However,  all residues concentrated N after 40 and 90 days incubation, probably because of their elevated initial C:N rates.