1.Bt crops Could Negatively Impact Soil
2.TWN Update of resources
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1.Bt crops Could Negatively Impact Soil
THIRD WORLD NETWORK BIOSAFETY INFORMATION SERVICE
Dear Friends and colleagues,
We wish to bring to your attention a recent study which investigated the potential effects of two Bt corn lines (Bt 11 and Bt 176) and their plant residues on arbuscular mycorrhizal (AM) fungi, which is a group of beneficial plant symbionts fundamental for soil fertility, a crucial factor for agricultural productivity.
The study found that both transgenic plants decreased AM's colonization and Bt 11 plant residues negatively affected AM establishment by indigenous endophytes four months after their incorporation into the soil.
It remains to be established whether mycorrhizal colonization is reduced directly by the Bt toxin present in corn litter or indirectly by soil microbial population alterations or by other factors.
Given that microbial communities are fundamental to soil fertility and quality, it is therefore important to conduct further long-term studies in the field to evaluate the impact of GM plants on these communities. In particular, the risk posed by GM plant residues to non-target beneficial soil microbes should be thoroughly investigated, since any reduction in their biodiversity might produce long-term effects on crops sequentially cultivated in the same soil in years to come.
With best wishes,
Third World Network
131 Jalan Macalister,
10400 Penang,
Malaysia
Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Website: www.biosafety-info.net and www.twnside.org.sg
Experimental Systems to Monitor the Impact of Transgenic Corn on Keystone Soil Microorganisms
by Turrini, A. (1) , Sbrana, C. (2), & Giovannetti, M. (3)
Keywords: GMO, environmental impact, arbuscular mycorrhizal fungi, coexistence, nontarget organisms
Abstract
Risks and benefits of transgenic crop plants should be evaluated not only by assessing pollen flow, but also by considering soil persistence of transgenic products, such as Bt toxins, which can accumulate in the soil and remain active for a long time.
Moreover, transgenic plants are often plowed under as crop residues, representing a potential hazard for nontarget arbuscular mycorrhizal (AM) fungi, a group of beneficial plant symbionts fundamental for soil fertility. In this study, we monitored the effects of transgenic corn plants (Bt 11 and Bt 176) and their residues on AM fungal growth and root colonization ability. Both transgenic plants decreased mycorrhizal colonization and Bt 11 plant residues negatively affected mycorrhizal establishment by indigenous endophytes four months after their incorporation into soil.
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(1) Department of Crop Plant Biology, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy, email: This email address is being protected from spambots. You need JavaScript enabled to view it.
(2) Institute of Biology and Agricultural Biotechnology, CNR, UO Pisa, Via del Borghetto 80, Pisa, Italy, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., Internet: www.ibba.cnr.it
(3) Department of Crop Plant Biology, University of Pisa, Via del Borghetto 80, 56124 Pisa, Italy, email: This email address is being protected from spambots. You need JavaScript enabled to view it., Internet: www.agr.unipi.it/dbpa/giovannetti
IFOAM Organic World Congress, Modena, Italy, June 16-20, 2008
Archived at http://orgprints.org/view/projects/conference.html
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2.TWN Update (of resources) for August 2008
Low Greenhouse Gas Agriculture
An FAO report argues that organic agriculture offers valuable techniques that could mitigate greenhouse gas emissions.
http://www.biosafety-info.net/article.php?aid=528
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Saying No to Chemical Farming in India
This article highlights the move by many farmers in India to switch from chemical-based agriculture to organic farming and the benefits they derived from it.
http://www.biosafety-info.net/article.php?aid=532
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Organic Agriculture and Food Security in Africa
This paper argues that organic agriculture can play a significant role in meeting the food security needs of Africa.
http://www.biosafety-info.net/article.php?aid=533