Bt maize: No impact on insect communities

For three summers in a row, Eva Schultheis and her team at RWTH Aachen University caught countless insects on the maize trial field and then identified the species in the laboratory. They wanted to find out whether the insect communities found in genetically modified Bt maize are different from those found in conventional maize. They found differences between the years and between individual maize varieties, but were unable to detect any influence of the genetic modification. Extensive investigations in the laboratory with the rice leaf bug, which was chosen as a representative species, also failed to find any negative Bt maize effects. GMO Safety spoke to Eva Schultheis about her research work.

Research Results

Butterflies like the peacock butterfly can come into contact with Bt maize if the pollen lands on their food plants.

“The pollen quantities that led to higher mortality rates in caterpillars in the laboratory were not detected in the field.”

Can butterflies be harmed by genetically modified Bt maize? This was the question that Mechthild Schuppener from RWTH Aachen University investigated in a three-year research project. She conducted a feeding study in the laboratory to find out how sensitive caterpillars are to Bt maize pollen. In the field, the scientist investigated how much maize pollen lands on butterflies’ food plants under natural conditions and examined where butterfly nests are to be found in farming areas. GMO Safety spoke to Mechthild Schuppener about the findings of her research project. more

Research Maize

Does Bt protein persist or break down during the agricultural cycle?

When genetically modified Bt maize is cultivated, Bt protein enters the soil via root exudates, harvest residues and pollen deposits. If Bt maize is used as cattle feed, Bt protein could also enter the soil through liquid manure spread on the fields. Scientists from the Bavarian State Research Centre for Agriculture (Bayerische Landesanstalt für Landwirtschaft) and the University of Technology in Munich (TUM) have for the first time investigated what happens to the Bt protein throughout the agricultural cycle – from cultivation to animal feed, to the spreading of liquid manure and the following crop. They were able to gain important insights into the breakdown and persistence of Bt protein in the soil following long-term Bt maize cultivation. more

Research Live

Bees in stress test

Bees are swarming around a pot containing yellow pollen feed. The newly emerged worker bees are obviously hungry. Over the next four weeks they will have to make do with pollen from just one maize variety. They are part of a feeding experiment being conducted at the University of Würzburg. A team at the Department of Animal Ecology and Tropical Biology is conducting a series of laboratory experiments to investigate whether bees can digest pollen from genetically modified Bt maize. more

Research Live

Nematodes: An indicator of soil quality

Nematodes or roundworms are found almost everywhere in the soil, in rivers and lakes, and even in the sea. They are the most common of the multicellular animals and have the greatest number of species. Sebastian Höss is studying nematodes that live in agricultural soil. He is conducting research on behalf of the Institute for Biodiversity in Regensburg, on whether nematodes are sensitive to genetically modified Bt maize.more

Research Live

‘Escape test’ with earthworms

It is the end of October 2010. Most of the maize trial field has been harvested. Scientists from RWTH Aachen University are digging holes in the ground one last time to count earthworms. They are investigating whether genetically modified Bt maize has an impact on these beneficial soil-dwelling creatures. In the laboratory, an earthworm ‘escape test’ will show whether earthworms avoid soil containing Bt proteins.more

Research Live

The rice leaf bug, Trigonotylus caelestialium, is very common on maize fields, which makes it a good model organism.

Mirid bugs not keen on all types of maize

The stacks of Petri dishes appear at first to contain nothing but pieces of maize leaves. It is only on closer inspection that the tiny creatures living inside the plastic dishes become visible. They are mirids in all stages of development. Eva Schultheis of RWTH Aachen University is conducting a feeding experiment with insects from her own breeding programme. It is designed to show whether genetically modified Bt maize harms the bugs. The rice leaf bug was chosen as a model organism because it is common in the maize field and ingests a lot of the Bt protein produced by the Bt maize when it feeds on the maize leaves.more

Research Results

“Looking at all the results, we can assume that cultivation of this maize does not pose a problem.”

From 2005 to 2008, a joint biosafety research group studied genetically modified MON88017 Bt maize, which has a new gene that makes it resistant to the Western corn rootworm. The research findings are now available. GMO Safety spoke to Stefan Rauschen of RWTH Aachen University, who has been coordinating the biosafety research into genetically modified maize since 2008. more