Biopesticide is widely used as a generic term to describe all biological pest and disease control products that are increasingly used in agriculture. With differing definitions and understandings of what should be included within biopesticides, the term bioprotectants has been introduced which is more clearly defined. Bioprotectants encompass all biological control agentsand are often placed in two categories – namely the biopesticides and macrobials or beneficial insects.
Biopesticides include 3 major categories:
Semiochemicals are emitted by plants, animals and other organisms, and are used to communicate within, or between, species. They are target-specific andhave a non-toxic mode of action.Microbial biopesticides are based on microorganisms, such as bacteria, fungi and viruses. Natural substances consist of one or more components that originate from nature, including but not limited to: plants, algae/microalgae, animals, minerals, bacteria, fungi, proteins/peptides, protozoans, viruses, viroids and mycoplasmas. They can either be sourced from nature or are nature identical if synthetized. This definition excludes semiochemicals and microbials.
Challenges to overcome
To improve sustainability and to minimise any negative, lasting impact on the environment and/or human health, growers are under increasing pressure from retailers and consumers to minimise their use of chemical pesticides. Also various authorities across the world have set targets to reduce the use of chemical pesticides by a certain date.
Growers used to have access to a large range of chemical crop protection products. However, in the last 10 years, more and more products have been banned. Also, over time, if the same active ingredient is used repeatedly, disease and pest populations have built up resistance rending many products less effective.
Additionally, very few new active ingredients have been introduced in the last 10 years. As a consequence, growers are being left with very few solutions.
Benefits of biopesticides
Providing effective and price competitive alternatives to chemical sprays, biopesticides can help to achieve sustainable crop protection.
Also, by helping to minimize the use of chemical sprays, biopesticides are helping to extend the life of these products by managing resistance build-up. Therefore, chemicals have to be considered as the last line of defence in IPM programmes.
Many bioprotectants are safe for beneficials and thereforethey can be used together with beneficials in an IPM programme.
When do we use biopesticides?
While biological pesticides are predominantly used preventatively to stop, or slow down, the establishment of a pest or disease in a crop, some are used as corrective solutions. It is important to understand the mode of action and practical ways of use before applying a biopesticide.