Pest practice

Combining biological and chemical pest control methods effectively in outdoor crops is a key challenge for the agriculture industry, explains Jennifer Lewis of Certis Europe.

“More public money is needed to develop such programmes in minor crops and this should be a key research target in the coming years”
-Jennifer Lewis, Certis Europe

How important is it that protection and pest control looks at the whole picture?
Jennifer Lewis. The recommended pest control approach of many practitioners is Integrated Crop Management (ICM), where pest control is considered within the context of the health and yield of the whole crop from sowing to harvest. In such a system, pest control requires crop monitoring to determine when any intervention is required and that any cultural and management techniques used, are aimed to prevent pest infestations. This approach is commonly known as Integrated Pest Management (IPM). In examples where IPM has become established, the pesticides used tend to be more specific and less broad spectrum, resulting in some secondary pests developing as the population dynamics in the crop change. New control methods are often needed to address these. Furthermore, the pest complex within a crop varies according to the climate as well as management factors. The crop system is therefore dynamic, so crop protection tools need to remain flexible to allow the appropriate control techniques to be used to ensure the production of quality produce. 

What options are open to growers when it comes to protecting their crops from pests and diseases?
Crop protection techniques range from cultural control through to whole management techniques, including biological methods such as beneficial insects and pheromones, microbial and physically acting methods, as well as conventional chemicals. Plant strengtheners and root enhancing techniques can also provide a level of defence against disease and are becoming more popular with growers.

What are the key challenges in offering protection that is effective right across the board?
Many pest control techniques are available for the major crops. The minor crops that represent smaller targets for industry have less pest control solutions. Innovative national schemes aim to address this including the Specific Off Label Application (SOLA) in the UK, where growers can apply to have a pesticide label use extended to a minor crop with submission of data. Grower groups are always keen to develop new pest control programmes and there are several examples of such groups co-funding research programmes with industry and public research bodies. One such programme is the soft fruit work being conducted at East Malling Research in the UK, where reduced residue programmes in raspberries and strawberries are being developed. More public money is needed to develop such programmes in minor crops and this should be a key research target in the coming years. Knowledge transfer to the growers is a critical part of this process.

Can completely organic approaches to pest control ever offer sufficient protection to crops?
Crops can be protected through organic means. It does however limit the growers' options and can be less cost effective than approaches that integrate conventional and biological control methods.

In the late 1990s the UK Tomato Growers Association set out a 10-year research programme to grow high quality tomatoes residue free. Within 10 years they had largely achieved this, using biological control throughout the growing season and pesticides as necessary. Pesticides are generally used to ensure the crop starts clean, to remove any pests at the end of the season, before the new crop is planted and to provide immediate control in the case of a pest outbreak.

The Tomato Growers have provided a case study of how integrated pest management can be implemented effectively across an industry, using all tools available to the grower.  In crops such as tomatoes that are grown under glass, it is easier to implement effective integrated control. The challenge facing the agriculture industry now is to combine biological and chemical control methods effectively in outdoor crops.

Integrated crop management is beginning with top fruit and citrus where commercialisation of pheromone-based mating disruption and mass trapping techniques are becoming common place. However, much work needs to be done to build robust examples across all food crops.

Pesticides are a precious tool that provide us with instant solutions to crop health problems. They are strictly regulated and those that are marketed need to be looked after as they provide instant solutions that would otherwise not be possible. Used wisely they are an essential element to the crop protection mix with minimal risk to the environment and residues.

An agronomy graduate with an MBA from Warwick University, Jennifer has held senior marketing and policy positions in the UK and Europe within leading multinational agrochemical businesses. Since she joined Certis Europe in 2005, she has been fully involved in the development of the group's integrated offerings, combining biological, physical and chemical control technologies in the speciality crop sector. During this time she ran the biocontrol operation within Certis Europe for three years.