Soil microbial response to glucose and phosphorus addition under agricultural systems in the Brazilian Cerrado

Abstract

Conventional tillage (CT) and no-tillage (NT) management systems alter soil nutrient availability and consequently modify soil microbial response to nutrient additions such as carbon (C) and phosphorus (P). The objective of this study is to evaluate microbial response to the addition of C (glucose) and P (Na 2 HPO 4 .7H 2 O) under CT and NT in the brazilian Cerrado. In response to glucose addition, the NT system yielded higher microbial respiration rates and glucose consumption than the CT system. The best microbial response to C addition was after 0 -12 h incubation in NT and 0 -24 h in CT. The addition of P produced higher demand under CT than NT. After incubation, biochemical indicators such as microbial respiration, glucose consumption, dehydrogenase activity and metabolic yield confirmed the higher glucose demands under NT and higher phosphorus demands under CT. These results demonstrate that C and P addition alter significantly the microbial response, suggesting that soil microorganisms present nutrient differential demands between CT and NT management systems.

Diversity and Function of Bacterial Assemblages in Savanna Vegetation Soils

“…This idea was later confirmed by DGGE analysis, which showed that nutrient addition, specifically P, produced a greater difference in the soil microbial community than the time of conversion of Cerrado to pasture, which resulted in another group of the DGGE cladogram of non-fertilized pasture and native shrubland. In a study evaluating microorganism response to P addition in Cerrado soil, Ferreira et al (2013) detected a relationship between P content and microbial activity and respiration in no-tillage and conventional-tillage systems.…”

Atividade e modelagem de fosfatase do solo como indicadores em agroecossistemas no cerrado

“…Entre os atributos utilizados de medida do estado anabólico do solo, pode se destacar a quantificação da massa celular, conhecida como biomassa microbiana medida indiretamente pelo teor de carbono, nitrogênio, enxofre ou fósforo, e a detecção da atividade de enzimas hidrolítica, medida sobre um substrato específico (BADIANE et al, 2000;TABATABAI, 1993;FERREIRA et al, 2013;VANCE et al, 1987).…”