Making organic pest and plague control possible

Dutch horticulturists protect the crops in their greenhouses with organic methods designed with the help of Wageningen. They deploy ichneumon wasps against the white fly, a method that Wageningen and its partners were already testing in the seventies of the last century. Ichneumon wasps and other biological helpers can reduce or eliminate the need for chemical pesticides.

Pest control

Despite the development of biological pest control methods, there is still an increase in the use of chemicals. The past four decades show that farmers’ use of chemical pesticides has increased fifteen to twenty-fold. This includes the Netherlands, where farmers sometimes have to resort to the use of chemicals against new and invasive plagues. The use of chemicals has a negative impact. They may harm the environment, and some chemicals are rendered useless as pests build a resistance to the substances.

Thus, the need for research on organic pest control remains, as does WUR’s pioneering role. In total, Wageningen scientists have identified over sixty species that can be deployed for pest control in greenhouses. Moreover, researchers are studying fungi that grow inside the plant and stimulate its growth, microbes that strengthen the roots and options to breed more resilient breeds. Factors such as the climate in the greenhouse, humidity and lighting are also being extensively studied. Gerben Messelink, endowed professor of Biological Pest Control in greenhouse horticulture, studies how biological enemies can complement each other.

Biological control is also applied in field crops, where conditions are less predictable than in the horticultural sector. Therefore, WUR scientists also study open situations for beneficial micro-organisms and flowering verges where natural enemies find shelter for survival.

Standing army

Much of Wageningen’s research aims to design farming systems capable of suppressing diseases and plagues naturally. These resilient growing systems have a standing army of helpful insects ready to combat pests and plagues. These beneficial organisms are present from the start of the growth rather than being deployed when a plague manifests. For example, planting wheat in the greenhouse provides a home for grain aphids, which serve as food for the ichneumon wasps. The wasps, in turn, attack the green peach aphid when it occurs.

Designing a resilient environment is only possible with extensive knowledge of all aspects of the growth process, including pests and plagues, their natural enemies, and the way plants respond to these organisms. This entire domain is covered by Wageningen University & Research, in close collaboration with other knowledge institutes and businesses in the agricultural sector. Thus, many biological control methods have made their way into the greenhouses, fields and orchards through Wageningen.