Record ID No. |
4913 |
Author(s) |
da Silva G S., *Diniz Melo C A., Teixeira Fialho C M., Tuf Santos L D., Dutra Costa M., da Silva A A. , 2014 |
Affiliation |
Universidade Federal de Viçosa (UFV), Departamento de Fitotecnia, Rua PH Rolfs s/nViçosa, MG, Brazil, *Email: chrisadinizmelo@yahoo.com.br |
Title |
Impact of sulfentrazone, Isoxafutole and oxyfuorfen on the microorganisms of two forest soils |
Source. Vol.(no):Page |
Bragantia 73(3): 292-299p. |
Categories |
Mycorrhiza General |
Subjects |
Biocides |
Host |
Eucalyptus grandis, E. urophylla |
Organism |
Mycorrhizal fungi |
Country |
Brazil, S. America |
Abstracts |
Questions regarding the application of pre-emergence herbicides for control weeds in eucalyptus are noteworthy due to the impact of this practice on the environment, particularly on soil microbial activity and benefcial microorganisms such as mycorrhizal fungi and phosphate solubilizing microorganisms. The aim of this study was to evaluate the impact of applying herbicides sulfentrazone, isoxafutole and oxyfuorfen on mycorrhizal colonization, microbial biomass and microbial activity of two forest soils cultivated with eucalyptus. The experiment was conducted in a greenhouse using two soils (clayey and sandy loam) distributed in 12 dm3 pots. The 4x3 factorial design was used, with three herbicides (sulfentrazone, oxyfuorfen, isoxafutole) over the untreated control and three assessments (5, 20 and 70 days after application (DAA)), in a completely randomized design with four replications. After herbicide application, seedlings of the hybrid Eucalyptus grandis x Eucalyptus urophylla were transplanted. We evaluated the microbial biomass, respiration rate, metabolic quotient and the potential of solubilization of inorganic phosphate at 5, 20 and 70 DAA. At 70 DAA verified the percentage of roots colonized by mycorrhizal fungi and spore viability in the soil. The sulfentrazone, isoxafutole and oxyfuorfen as well as the time of application afected the microbiological indicators differently. In the sandy loam soil sulfentrazone was more harmful to microbial biomass, mycorrhizal colonization and microorganisms solubilizing inorganic phosphate. However, in clayey soil, the application of the three herbicides did not affect microbial biomass, but the root colonization of eucalyptus by mycorrhizal fungi and the potential solubilization of inorganic phosphate were reduced. The sulfentrazone caused an increase in the number of non-viable spores of mycorrhizal fungi in the soil. |