assume that plant extracts are safe. Likewise, compounds such as pyrethrum are subject to insecticide resistance (or cross-resistance with synthetic pyrethroids) and may be toxic to bees. A major obstacle for commercialisation and wider availability of botanical products in the region is the inability of local manufacturers and the regulatory system to properly address characterisation and risk assessment of plant extracts with multiple active ingredients. This is also a problem at the international level. A seminar on botanical extracts was organised by the OECD BioPesticides Steering Group (BPSG) (43); in their summary, key issues to be addressed included the following statements: • “It is clear that the term ‘botanical’ covers a very diverse group of compounds therefore, depending on the characteristics of an active substance, flexibility and consideration on a case-by- conventional chemicals and there are problems of how to provide technical specifications. Plant extracts are complex mixtures of a wide range of chemical compounds and biological activities. Various approaches are under evaluation including: (i) the biomarker approach in which the key compounds of the bioactive plant extract are determined. This approach can be used for quality assurance but it is unclear how this is related to the efficacy of the substance/product. (ii) Biocide 'whole extract' approach, but this may lead to 'variability issues' (iii) Blending (technical mixture of active substances) may be an option8.” • “It is still unclear how to deal with synthesised analogues or mimics, which are nature identical but synthesised versions. Should they be treated as 'conventional chemicals'? In this respect it should also be mentioned that radio-labelling techniques are impossible to use for plant extracts. A more balanced approach is needed.” ASEAN regulatory experts worked together to define “Minimum data requirements for botanicals’ (Appendix II) that consider some of the points mentioned above. In the meantime, while the present document was under preparation, the EU has issued an updated guidance on the regulation of botanicals (79), which could serve as a valuable source to develop further the issues discussed above. It was proposed in the work meetings that botanicals should not be compared directly with synthetic pesticides when it comes to measuring effectiveness in the field. Botanicals degrade quickly in the environment and are less rain-fast than synthetic products, which may result in lower short-term performance and require different application tactics; this should be acknowledged by regulators and users as well. The value of plant extracts is most apparent during early growing stages, at low pest pressures and against young larvae rather than adult insects. These principles are documented in a field testing protocol that was jointly developed by the regional BCA expert group (Appendix III). 24 case may be needed.” • “It is also clear that the issue of specification for 'botanicals' is more complex than for 8 But such an approach would hardly result in “natural products”
Implementing Biological Control Agents in the ASEAN Region
To see the actual publication please follow the link above