A few weeks ago three ‘bee killers’, neonicotinoid sprays and seed treatments, were temporarily banned in Europe. The banned insecticides are dinotefuran, imidacloprid and thiamethoxam. Now cereal farmers outside Europe are talking about what the neonic ban means for them.
Within the last few decades, insects called planthoppers have become serious pests on rice. Perhaps that’s due to overuse of insecticides – neonics and others – which are ‘broad-spectrum’. That means, they kill many kinds of insects. ‘Good bugs’ along with ‘bad bugs’.
If you kill off lots of insects, you’ll disrupt the whole ecosystem. That’s why the Pesticide Action Network for Asia and the Pacific calls planthopper outbreaks on rice a man-made plague.
At the International Rice Reserch Institute (IRRI), senior scientist Bas Bouman tells us about the neonic ban’s implications for Asian rice farming. He recommends Integrated Pest Management (IPM). IPM ‘teaches farmers to distinguish between the “good bugs” (predators, parasitoids) and the “bad bugs” (insect pests such as planthoppers), and shows them nonchemical alternatives to fight the “bad bugs”.’
I like Dr Bouman’s summary of what IPM has to offer Asian farmers. Farmers can rotate crops, so that each field grows a different kind of crop each year. Farmers can diversify, growing several crop species and varieties. They can make informed choices about when to plant crops and when to leave some fields fallow. They can choose crop varieties that differ in their mechanisms of resistance or tolerance to pests. Another option is for farmers to cooperate with their neighbours, doing ‘ecological engineering’. That means bringing in, for example, flowers to support parasitoids and predators which will attack the planthoppers.
‘IRRI and its GRiSP [Global Rice Science Partnership] partners in Asia are pioneering the introduction of ornamental flowers and agricultural plants such as okra and sesame on bunds in rice fields to attract the “good bugs” to help control planthoppers. Ecological engineering not only helps combat planthoppers but also enhances the scenic quality of the environment, can provide additional income, and may attract bees that can stimulate a local industry of honey production.’
Neonics aren’t yet banned in Asia. It might be a very good thing if they were banned everywhere and if more farmers turned to IPM.