Additional advisory report on cultivation of maize line 59122
This advisory report concerns the cultivation of the genetically modified maize line 59122. The maize line contains the cry34Ab1, cry35Ab1 and pat genes conferring tolerance to glufosinate-ammonium-containing herbicides and resistance to certain coleopteran insects such as the corn rootworm (Diabrotica spp.).
Previously, COGEM concluded that the cultivation of maize line 59122 most likely poses a negligible risk to human health and the environment. However, COGEM was of the opinion that case specific monitoring of ladybirds should be carried out.
Recently, EFSA published its opinion on cultivation of genetically modified maize 59122. The Dutch Ministry of Infrastructure and the Environment (IenM) asked COGEM whether the opinion of the EFSA GMO panel and the additional information that is provided by the applicant gives reason to reconsider the necessity for case specific monitoring of ladybirds (Coccinellidae).
In its previous advice, COGEM was of the opinion that monitoring of ladybirds is necessary because in laboratory experiments exposure of ladybird larvae to high levels of Cry34Ab1/Cry35Ab1 proteins resulted in a reduced larval weight, which might affect the rate of reproduction.
The applicant performed additional studies to assess possible adverse effects on Coccinella septempunctata, a ladybird common in Europe. However, in these studies, ladybirds were exposed to low or unknown levels of Cry34Ab1/Cry35Ab1 proteins, making it impossible to draw conclusions on the absence or presence of an effect.
Additional field trials with 59122 maize were performed in Hungary in which visual observations were carried out to obtain more information on the occurrence of coccinellid species in maize fields. In all plots of the field trial (planted with 59122 maize or the non-transgenic control) ladybirds were present in low numbers. Due to the low abundance of ladybirds the results cannot be used to draw conclusions about possible effects of 59122 maize on ladybirds.
In summary, the additional information does not remove COGEM’s previous concerns. Therefore, in case 59122 maize is authorised for cultivation in COGEM’s view case specific monitoring of ladybirds, in particular of spider mite consuming ladybirds (i.e. ladybirds belonging to the Stethorini tribe), remains a necessity unless conclusive additional experimental data is provided showing unequivocally the absence of an effect.