43. Effect of tillage and N fertilization on microbial physiological profile of soils cultivated with wheat

GABRIELA DIOSMA MONICA AULICINO HUGO CHIDICHIMO Y PEDRO A. BALATTI

SOIL & TILLAGE RESEARCH

Elsevier

Año: 2006 p. 236 - 243

0167-1987

Microbial diversity might be a good indicator of ecosystem disturbance and functioning. We determined the effect of soil disturbances, such as N fertilization and tillage management, on soil microbial communities in a Typic Argiudoll of the El Salado river basin (Argentina). Microbial activity and substrate utilization provided a metabolic fingerprint of the soil microbial community. Univariate and multivariate analyses were used to differentiate responses to N fertilization and tillage at each of three growth stages of wheat (Triticum aestivum L.). Tillage had an adverse effect on microbial diversity, reduced and conventional tillage treated soils had diverse populations. However, N fertilization also altered microbial diversity depending on the crop developmental stage considered. Metabolism of carboxylic acids and carbohydrates were the main indicators of functional microbial activity and diversity. Although the substrate consumption profile of 32 C substrates did not provide insights into the fundamental ecological interactions that may induce changes in microbial population, it allowed us to demonstrate the alterations of microbial diversity as a result of tillage. We conclude that tillage and N fertilization altered microbial diversity.Triticum aestivum L.). Tillage had an adverse effect on microbial diversity, reduced and conventional tillage treated soils had diverse populations. However, N fertilization also altered microbial diversity depending on the crop developmental stage considered. Metabolism of carboxylic acids and carbohydrates were the main indicators of functional microbial activity and diversity. Although the substrate consumption profile of 32 C substrates did not provide insights into the fundamental ecological interactions that may induce changes in microbial population, it allowed us to demonstrate the alterations of microbial diversity as a result of tillage. We conclude that tillage and N fertilization altered microbial diversity. # 2006 Elsevier B.V. All rights reserved.2006 Elsevier B.V. All rights reserved.