A committee hearing public submissions on an application by crown research institute Crop and Food Research to conduct field tests on genetically modified vegetables will begin its first day of deliberations on Wednesday.
The institute is seeking approval from the Environmental Risk Management Authority to grow genetically modified onions, spring onions, leeks and garlic at its site in Lincoln, near Christchurch, over 10 consecutive years.
It would involve planting seeds directly into the ground and allowing some plants to flower.
Some of those making submissions expressed concern that it would be impossible to prevent some of the genetically modified pollen from being spread into the surrounding environment.
Fifteen parties made submissions at the hearing in Christchurch on Tuesday.