Description of the measure

The application frequency of the pesticide can be reduced to achieve acceptable risk, while still resulting in effective control.

Alternatively, the interval between succeeding applications can be increased.

Conditions for effective implementation

The application frequency of the pesticide should be reduced, or the treatment interval increased, without significantly affecting the pesticide’s efficacy.

Estimated risk reduction potential

The risk reduction potential will often be approximately proportional to the reduction in the number of applications. However, if certain applications of the high-risk pesticide are being replaced by a lower-risk pesticide, the remaining risk of using the low-risk product should be taken into account.

An increase in application interval will lead to a longer period with low/no pesticide residues on the crop or in the environment. The risk reduction potential from an increase in application interval will depend to a large extent on the degradation rate of the pesticide.

Potential constraints

In principle, the reduced application frequency should be chosen so it still leads to sufficient efficacy against the pest, weed or disease. There would thus not be an adverse effect on efficacy.

In many cases this is achieved by replacing the high risk pesticide by a low-risk product, but maintaining the overall application frequency. In other cases, it may be achieved by changing from calendar-based pesticide applications to treatments based on observance of pest infestation (and natural enemy) levels.

Further information

Recommendations on pesticide efficacy trials and setting recommended application frequencies can be found in the Application and Efficacy module under the Assessment Methods Tool, or in the FAO Guidelines on efficacy evaluation for the registration of plant protection products.