Boîte à outils pour l’homologation des pesticides

Step 2. Evaluate crops/pests for which alternative(s) need to be sought

Purpose

This step aims at evaluating the extent of the pest problems, and identify the priority crop-pest combinations that require alternatives for the registered HHPs.

The starting point of this step is the list of current uses of the HHP (crop–pest combinations) for which alternatives may be required (= outcome of Step 1). However, since this list can be long, alternatives to HHPs may need to be identified as a priority for crop-pest combinations or other uses with the highest agronomic, economic or public health importance.

Information required and possible sources

for each crop–pest combination or use:

Information

Possible sources

Geographical extent of the pest.

 

  • Plant protection officers
  • Agricultural extension officers
  • Major pesticide users (e.g. large farms, government users (e.g. for disease vector control)
  • Agricultural producer associations
  • Farmers (e.g. through surveys)
  • Pesticide distributors and dealers
  • Research institutes

 

Importance of the pest: i. levels of damage caused; ii. levels of crop loss; iii. levels of economic loss.

Situations in which the pest appears to cause damage, crop loss or economic loss, and situations in which it does less/not (e.g. geographical, timing, climate, crop management practices).

 

  • Research institutes
  • Studies from other countries
  • Plant protection officers
  • Agricultural extension officers

 

Efficacy of use of the HHP to reduce damage, crop loss and economic loss.

 

  • Research institutes
  • Plant protection officers
  • Studies from other countries

 

Efficacy of use of other pesticides or pest management approaches, including biocontrol or IPM.

 

  • Research institutes
  • Plant protection officers
  • Studies from other countries

 

Procedures

  • Consult with plant protection officers, extension staff, pesticide users, research institutes and pesticide distributors and dealers, to obtain a complete as possible picture of the geographical distribution of the pest as well as its importance. Often, quantitative information about the importance of the pest (i.e. levels of damage, crop loss and economic loss) may not be available or is incomplete, and a (semi-)qualitative assessment will then need to be conducted.
  • Consult with research institutes, plant protection and agricultural extension officers, (bio)pesticide distributors and other relevant sources on the efficacy of use of the HHP as well as of other pest management practices which are used in the country, including any biocontrol and IPM. Published studies from other countries may be informative if agro-ecological conditions are similar or can be extrapolated. Care should be taken to recognize bias in the estimation of the efficacy of pest management approaches, especially if it is not properly quantified.

    Further guidance on the evaluation of efficacy of pesticides in agriculture is available from FAO and from the European and Mediterranean Plant Protection Organization (EPPO)
  • Note whether any other problems exist in the management of the crop–pest combination, e.g. frequent pest outbreaks, resistance development. These issues may need to be considered in the deployment of alternative pest management strategies.
  • Analyse and discuss the information gathered with the aim to prioritize the crop–pest combinations for which alternative management options need to be identified.

 

Example summary of an evaluation of the importance of the pests against which HHP-X is used, in a hypothetical country

Active ingredient: HHP-X

Crop

Pest

Geographical distribution of the pest

Importance of pest

Efficacy of HHP

Efficacy of other pest management

Remarks

Possible conclusions:

 

  • Fall armyworm in maize: Crop loss is localized and very variable. It is difficult to ensure acceptable risk when HHP-X is applied by smallholder farmers. Effective alternatives for HHP-X in maize appear to be available, although their use may require further attention.
  • American bollworm in cotton: Even though no local studies about economic losses due to bollworm are available, potential yield losses appear to be considerable. Only one alternative, Insecticide-Z, seems to be used widely, but resistance is developing against it, so its use may not be effective in the near future. No biocontrol options are available. Large quantities of HHP-X are currently used in the country against this pest (see Example summary in Step 1).
  • Priority crop-pest combination for which alternatives need to be sought as a priority: American bollworm in cotton.

 

Maize

Fall armyworm (Spodoptera frugiperda)

Countrywide; but most outbreaks seen in north-eastern districts

Localised outbreaks with highly variable damage and crop loss, ranging from 0-100%

HHP-X reduces armyworm populations locally by 40-70%, dependant on larval instar and weather conditions (rain)

Several low-risk insecticides are registered against fall armyworm, but they are more expensive

Biocontrol with NPV is effective if applied when larvae are young; NPV can be locally produced

Smallholder farmers apply insecticides using no or only basic PPE

Cotton

American bollworm (Helicoverpa armigera)

District A

District B

District C

Yield loss ranging from 10-50%, mainly observed in districts A & B

Economic loss dependent on cotton price, reportedly ranging from 5-35%

No local economic studies available

HHP-X reduces bollworm populations by max. 75%

No economic cost-benefit assessment of using HHP-X is available

Insecticide-Z is widely used, and has lower acute toxicity than HHP-X

No biopesticide is marketed against bollworm

Moderate development of field resistance against Insecticide-Z is confirmed

Outcome of Step 2

  • Prioritization of crop–pest combinations for which alternatives need to be sought.
  • Problems with current pest management practices to be addressed in the overall alternative pest management strategy.

 

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