Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Additive Copper-Zinc Interaction Affects Toxic Response in Soybean

12.11.2009
Agricultural soils accumulate trace metals, particularly copper and zinc, as a result of their presence in wastes (sewage biosolids and manures) and fungicides that are applied over long periods of time.

Regulations and guidelines for tolerable concentrations of these potentially plant-toxic elements in soils are based on the assumption that the toxic effects of the metals are substantially independent and not additive.

However, additivity would imply that soil tolerance limits for each metal must be adjusted to compensate for the presence of another metal. There has been very little experimental work to date to provide a basis for determining the degree to which copper-zinc interaction in soils is additive as defined by the toxicity response in crops.

Researchers at Cornell University have investigated the copper-zinc interaction in two soils with different textures, using soybean growth and metal uptake into leaves to evaluate both toxicity and availability of these metals to the plants. Soybean crops were grown in pots in the field in two successive years after allowing copper and zinc sulfate-amended soils to age in the field for one year prior to the first planting. Copper and zinc were added to individual soils to provide 0, 50,100, 200, and 400 mg/kg of each metal as well as every possible combination of addition levels of the two metals. The results from the study are published in the November-December issue of Journal of Environmental Quality.

Interactive effects of copper and zinc were observed both in the soil as well as in the soybean toxic response. In the soil, high copper had a strong effect on inhibiting zinc adsorption on soil particles, thereby causing zinc to be more easily extractable and available. Conversely, there was only a moderate interactive effect of zinc on copper adsorption, probably explained by the higher affinity of copper for soil adsorption sites, particularly those associated with organic matter.

The toxic effects of copper and zinc on soybean growth was found to be additive to a large degree, as measures of both extractable copper and zinc in the soils were needed to adequately explain the inhibition of plant growth over all treatments. However, the toxic effect of copper was stronger than that of zinc, possibly explained by the observed severe impact of copper on soybean root development. Soil texture had a marked influence on the degree of copper and zinc toxicity and availability to soybeans, consistent with numerous studies that have shown coarse-textured soils to be more susceptible to the toxic effects of heavy metals on crops.

The results from the study indicate that guidelines for tolerable upper limits of copper and zinc concentrations in soils are likely to require allowance for the presence of a second toxic metal at elevated concentrations, which could lower the tolerable limit for either copper or zinc. Furthermore, tolerable limits for copper and zinc in soils are likely to be lower in coarse-textured soils.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at http://jeq.scijournals.org/cgi/content/abstract/38/6/2253.

The Journal of Environmental Quality, http://jeq.scijournals.org is a peer-reviewed, international journal of environmental quality in natural and agricultural ecosystems published six times a year by the American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and the Soil Science Society of America (SSSA). The Journal of Environmental Quality covers various aspects of anthropogenic impacts on the environment, including terrestrial, atmospheric, and aquatic systems.

The American Society of Agronomy (ASA) www.agronomy.org, is a scientific society helping its 8,000+ members advance the disciplines and practices of agronomy by supporting professional growth and science policy initiatives, and by providing quality, research-based publications and a variety of member services.

Sara Uttech | Newswise Science News
Further information:
http://www.agronomy.org

More articles from Agricultural and Forestry Science:

nachricht New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign

nachricht Fighting a destructive crop disease with mathematics
21.06.2017 | University of Cambridge

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>