The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment.
The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment.
Crop management practices, including the addition of fertiliser, often lead to different microbia... more Crop management practices, including the addition of fertiliser, often lead to different microbial communities in agricultural soils. Soil dilution plates were used to enumerate yeasts, basidiomycetous fungi, general hetrotrophic microbes, as well as actinomycetes in soils sampled at three times (winter, spring, early summer) within and between rows of plots planted to a wheat monoculture and wheat legume rotation. An adapted version of the buried slide technique was used to measure the numbers of filamentous microbes in the soil. Seasonal changes (July-November) were evident in all measured microbial populations in both plots sampled. Whereas most microbe populations showed similar or declining numbers from winter (July) to spring (September), general heterotrophic counts increased slightly in the monoculture plot, while filamentous growth increased within crop rows in the monoculture plot. Biolog EcoplatesTM were used to give an indication of spatio-temporal changes in the soil bacterial metabolic profile. A seasonal shift occurred in the ability of the bacterial community to assimilate carbon sources with more organics acids utilised in November than in July. Fungi, capable of anaerobic growth, occurred more abundantly in the soil of the monoculture plot. This study indicated the efficacy of using simple culture methods, in combination with the buried slide method, to detect fine-scale and short-term temporal changes in the abundance of metabolic activity of important microbial populations in soils subjected to different agronomic practices
The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment. These soil samples were used to measure culturable protozoa (most probable number method) and the potential metabolism of the
Different plants are known to have different soil microbial communities associated with them. Ag... more Different plants are known to have different soil microbial communities associated with them. Agricultural management practices such as fertiliser and pesticide addition, crop rotation and grazing animals can lead to different microbial communities in the associated agricultural soils. Soil dilution plates, most-probable-number (MPN), community level physiological profiling (CLPP), buried slide technique as well as some measured soil physicochemical parameters were used to determine changes during the growing season in the ecosystem profile in wheat fields subjected to wheat monoculture or wheat in annual rotation with medic/clover pasture. Statistical analyses showed that soil moisture had an over-riding effect on seasonal fluctuations in soil physicochemical and microbial populations. While within season soil microbial activity could be differentiated between wheat fields under rotational and monoculture management, these differences were not significant.
The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment.
The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment.
Crop management practices, including the addition of fertiliser, often lead to different microbia... more Crop management practices, including the addition of fertiliser, often lead to different microbial communities in agricultural soils. Soil dilution plates were used to enumerate yeasts, basidiomycetous fungi, general hetrotrophic microbes, as well as actinomycetes in soils sampled at three times (winter, spring, early summer) within and between rows of plots planted to a wheat monoculture and wheat legume rotation. An adapted version of the buried slide technique was used to measure the numbers of filamentous microbes in the soil. Seasonal changes (July-November) were evident in all measured microbial populations in both plots sampled. Whereas most microbe populations showed similar or declining numbers from winter (July) to spring (September), general heterotrophic counts increased slightly in the monoculture plot, while filamentous growth increased within crop rows in the monoculture plot. Biolog EcoplatesTM were used to give an indication of spatio-temporal changes in the soil bacterial metabolic profile. A seasonal shift occurred in the ability of the bacterial community to assimilate carbon sources with more organics acids utilised in November than in July. Fungi, capable of anaerobic growth, occurred more abundantly in the soil of the monoculture plot. This study indicated the efficacy of using simple culture methods, in combination with the buried slide method, to detect fine-scale and short-term temporal changes in the abundance of metabolic activity of important microbial populations in soils subjected to different agronomic practices
The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soi... more The glyphosate, Roundup, is used worldwide to combat weeds, but knowledge about its effect on soil microbes is limited. Even though this commercially available herbicide is usually considered safe for the environment, there are still some concerns about its long-term effect on soil microbes, plants, animals and humans. Several articles about the supposedly harmful effects of Roundup are available, especially in the more popular media and on the internet. Soil microbes play an important role in the cycling of mineral elements in the soil and the maintenance of a healthy soil microbe community is of utmost importance to farmers. Some farmers are in the habit of using sucrose or molasses as soil amendments, since the use of these easily obtainable carbon sources as food sources for microbes has been documented. Some farmers add these to their herbicides in order to minimise its possible effect on the beneficial microbial populations. The simple carbohydrate acts as possible substrate instead of the root exudates from living plants that usually act as food source for the microbes. In this study, the effect of the glyphosate containing herbicide Roundup was tested, with or without added sucrose, on some aspects of soil microbial communities. The soil was sampled at three times, namely before treatment, a week after treatment and twenty days after treatment. These soil samples were used to measure culturable protozoa (most probable number method) and the potential metabolism of the
Different plants are known to have different soil microbial communities associated with them. Ag... more Different plants are known to have different soil microbial communities associated with them. Agricultural management practices such as fertiliser and pesticide addition, crop rotation and grazing animals can lead to different microbial communities in the associated agricultural soils. Soil dilution plates, most-probable-number (MPN), community level physiological profiling (CLPP), buried slide technique as well as some measured soil physicochemical parameters were used to determine changes during the growing season in the ecosystem profile in wheat fields subjected to wheat monoculture or wheat in annual rotation with medic/clover pasture. Statistical analyses showed that soil moisture had an over-riding effect on seasonal fluctuations in soil physicochemical and microbial populations. While within season soil microbial activity could be differentiated between wheat fields under rotational and monoculture management, these differences were not significant.
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