New weapon in the fight against slugs
A tiny one millimetre worm may soon be the latest tool for farmers in the war against slugs.
The nematode, named Phasmarhabditis hermaphrodita, infects and kills slugs and has been available in Europe as a biological control for the past 20 years.
Work by the Foundation for Arable Research (FAR) confirmed that the nematode had been long present in New Zealand.
This allowed FAR to convince the Environmental Protection Authority to change its status under the Hazardous Substances and New Organisms Act, so it could now be used in New Zealand, Agresearch senior scientist Mike Wilson said.
FAR could soon undertake field trials to compare biological slug control with chemical baits, Wilson said at FAR’S annual field day at its northern crop research site at Tamahere.
The relaxing of its environmental status also opened the door for the commercialisation in New Zealand of Nemaslug, a European product which contained millions of the nematodes which were sprayed out onto crops.
Wilson said discussions were being held with BASF, the sole providers of Nemaslug, about making the product available in New Zealand. Using the biological control was a more environmentally friendly alternative compared with chemical slug bait and could potentially provide a greater level of control if used properly, he said.
In the meantime, FAR and Agresearch had continued to run trials comparing slug control with yields in maize crops at Tamahere. Wilson updated farmers on the latest results of those trials at the field day.
The experiments looked at the effect slug damage had on maize crop yields.
A large, direct drilled plot was sown and this crop would be measured at different times through to harvest.
The crop was divided into eight sub-plots that were either untreated or treated with slug bait. The difference in growth between the treated and untreated was clearly visible, Wilson said.
The trial used the slug bait Endure, a Ravensdown product and put three applications on at 12 kilograms a hectare.