Biodegradation of glyphosate by microbiota of soils of apple tree fields
01/Oct/2014
Glyphosate is a systemic post-emergent herbicide of the non-selective organophosphate group widely used in apple orchards in the South of Brazil. It may have adverse effects on beneficial soil microorganisms. The aim of this study was to evaluate the biodegradability of glyphosate by soil microbiota in apple orchards with different histories of application of the product. For that purpose, soil samples from the region of Vacaria, Rio Grande do Sul, were used, with the biodegradation of glyphosate being evaluated by […]
Arbuscular mycorrhizal fungi: diversity, composition and glomalin area and degraded revegetated with sesbânia
01/Apr/2014
The community composition and diversity of arbuscular mycorrhizal fungi (AMF) can be affected by several factors, including the climate, soil biota and host plants. This study aimed to evaluate the influence of Sesbania virgata (SV) revegetation in pure and intercropped with plantation Eucalyptus camaldulensis (EC) and Acacia mangium (AM), in the composition and diversity of arbuscular mycorrhizal fungi (AMF), and the amount glomalin-related soil protein (GRSP) in an area damaged by clay extraction. The experimental design was a randomized block […]
Soil microbiology in high schools of Lavras, Minas Gerais
01/Feb/2012
Microorganisms have relevant functions in the sustainability of ecosystems and for life on the planet, although society is generally not aware of this role and considers only the domain of pathogens. The purpose of this study was to analyze the content about soil microorganisms conveyed to students by biology textbooks of high schools in Lavras, State of Minas Gerais. Students and teachers from three schools of this city were described and the knowledge about soil microbiology of 334 high school […]
Microbial alterations of the soil influenced by induced compaction
01/Oct/2009
Compaction is one of the most destructive factors of soil quality, however the effects on the microbial community and enzyme activity have not been investigated in detail so far. The objective of this study was to evaluate the effects of soil compaction caused by the traffic of agricultural machines on the soil microbial community and its enzyme activity. Six compaction levels were induced by tractors with different weights driving over a Eutrustox soil and the final density was measured. Soil […]
Effects of soil characteristics on hexachlorobenzene degradation
01/Jun/2006
Artificial changes in the properties of a soil contaminated with hexachlorobenzene were promoted in order to study the effects on the microbial community and the degradation of this compound. The soil samples were flooded or enriched with organic material or lime under laboratory conditions. The microbial activity and density as well as the total (mineralization) or partial hexachlorobenzene degradation (transformation into metabolites) were analyzed. The mineralization of 14C-hexachlorobenzene was analyzed by adding a 14C-hexachlorobenzene solution to soil samples, capturing the […]
Assessment of soil properties by organic matter and EM-microorganism incorporation
01/Jun/2003
Properties of a claim loam soil, collected in Aranjuez (Madrid) and enriched with organic matter and microorganisms, were evaluated under controlled temperature and moisture conditions, over a period of three months. The following treatments were carried out: soil (control); soil + 50 t ha-1 of animal manure (E50); soil + 50 t ha-1 of animal manure + 30 L ha-1 of effective microorganisms (E50EM); soil + 30 t ha-1 of the combination of various green crop residues and weeds (RC30) and soil + 30 t ha-1 of the combination of […]
Effects of soil disinfestation by solar energy on arbuscular mycorrhizal fungi
01/Mar/2002
Besides its low cost, solar energy use in soil disinfestation presents no risks for human health and the environment. However, its effects on beneficial microorganisms are not well known. This study evaluated the effect of a solar collector and solarization on an indigenous population of arbuscular mycorrhizal fungi. Inoculum potential of mycorrhizae, determined by the most probable number method, decreased, respectively, 93 and 99% when soil was treated during 30days by solarization and solar collector. Mycorrhizal colonization of maize plants, […]
Release of bound residues of atrazine from soils through autoclaving and gamma radiation sterilization
01/Dec/1997
The sterilization methods are particularly important to study the influence of microorganisms on the pesticide dissipation in soils. This study, conducted in the laboratories of the Instituto Biológico of São Paulo in august 1996, tested the influence of two methods of soil sterilization – moist heat (autoclaving) and γ radiation – on the release of nonextractable or bound residues. It was studied, as example, bound residues of the herbicide atrazine in two types of soil (gley humic and dark red […]