Resumo

TORRES, Martha Viviana  e  LIZARAZO, Luz Marina. Evaluation of functional groups (cycles of C, N, P) and activity of the acid phosphatase in two agricultural soils of Department of Boyacá (Colombia). Agron. colomb. [online]. 2006, vol.24, n.2, pp.317-325. ISSN 0120-9965.

Microbial community of agricultural soils is a component with multiple functions that are essential for soil fertility. This research was undertaken in order to study bacteria populations participating in the biogeochemical cycles of C, N, and P, with the purpose of evaluating their presence in the cultivation systems and determining possible interactions among these groups in the rhizosphere and total soil. In a similar way, determination of the enzymatic activity of the acid phosphatase was done. The evaluation of the functional groups was carried out by recount in plate and estimation of the acid phosphatase activity using the method of Tabatabai and Bremner (1969, 1977). The phosphate solubilizing bacteria were present in smaller proportion than functional groups of the cycle of C and, in two soils, maintained population sizes similar to that of free-living nitrogen fixing bacteria in rhizosphere and total soil. According to the results obtained in these agricultural soils, the difference in the proportion of microorganisms between rhizosphere and surrounding soil can vary because of the fertilizer additions. Also, it was determined that activity of the acid phosphatase in these two soils could be affected by such factors as percentage organic matter, bacterial biomass, and phosphorus availability.

Palavras-chave : acid phosphatase; celulolitics; amilolitics; proteolitics; free-living nitrogen fixing bacteria; solubilizers of phosphorus.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )