Overview:
- Why is choosing the right application method important?
- What to consider when applying a biocontrol or biopesticide product
- Knowledge of the pest’s life cycle and behaviour
- Knowledge of the product and formulation
- Knowledge of technical application parameters
Biocontrol and biopesticide products play a vital role in crop protection as effective and sustainable alternatives to chemical pesticides. While biocontrol and biopesticide products have many benefits, their efficacy largely depends on correct application of the product. Here, we discuss the critical aspects of applying biocontrol and biopesticide products, such as choosing the right equipment, considering the environment and pest, and understanding technical parameters.
Why is choosing the right application method important?
Selecting the right application equipment and technical application parameters is crucial for the effective distribution, on or around the plant, of a plant protection product. For instance, many biopesticides need to come into direct contact with the pest, so good coverage of the target crop is essential.
Proper equipment and correct technical application parameters will help to ensure that the product reaches the pest in the right concentration. Correct application also reduces the amount of product that directly or indirectly misses the crop (and is therefore wasted).
Biological products often require close attention to application timing, storage, and volumes used. Incorrect application methods can lead to significantly reduced product efficacy, making it unable to manage the pest problem.
What to consider when applying a biocontrol or biopesticide product
Correct product application involves a good understanding and knowledge of several factors. This will maximize the product’s efficacy while limiting the environmental impact. The following factors must be considered:
- Knowledge of the pest’s life cycle and behaviour
- Knowledge of the product and formulation
- Knowledge of technical application parameters
Knowledge of the pest’s life cycle and behaviour
The first step in identifying the correct application method and equipment needed is to know your pest.
What is my pest and where is it located?
Correctly identifying your pest helps you find the product that will work against it. Knowing the location where your pest normally resides (i.e. on or under plant leaves, in the soil, etc.) will then help ensure that the product is concentrated where the pest is the most abundant.
When is the pest most susceptible?
You can determine the best moment for control by considering the pest’s lifecycle. For example, some biopesticides are more effective against certain pests during their larval life stages. By having this information, you can apply the product during a time in the season where it will have maximum impact.
What is the pest mobility?
Knowing how the pest moves, for example, whether the pest flies, crawls or dwells in the soil, helps determine coverage requirements and droplet size.
Knowledge of the product and formulation
Understanding the specifics of a biopesticide is essential for choosing the right equipment and effective application. This includes knowing the product’s mode of action, the type of formulation it comes in, and the best methods for its application.
- Read ‘7 tips to pick a biopesticide or biocontrol product’ to find more information on choosing and understanding your product.
What is the mode of action?
A product’s mode of action tells you how the product works against the target pest. This can be important for determining the appropriate application technique. For example, does the product need to come into contact with the pest directly, or does the pest need to ingest it? If the latter, for example, the product must be applied where the pest feeds.
How is the product formulated?
There are many formulations of biological products: liquid solutions, pellets, granules, dust, etc. Some products do not require further preparation, such as living organisms (macrobials) that can be released from their package of origin, or certain microbials that are supplied and applied as granules. Most products must be dissolved in a solvent, often water and, less commonly, oil, before application.
The solubility of a product refers to how well it dissolves in a solvent. This determines how you should mix and prepare the product. There are some calculations you will need to do to get the proper dilution of the product to achieve the correct concentration.
- The Crop Sprayer App is a free tool that helps you calculate how much product to use when treating your crops. You can use it to calculate the amount of pesticide concentrate to put in the tank, how many spray tanks will be needed to spray an area and how much pesticide concentrate will be required in total.
If you need to store the product after its preparation, make sure to do it according to the product’s label to ensure that it remains effective until the time of application.
What type of application equipment is needed?
Once you have gathered information on the pest, the product’s mode of action, and the product formulation, you can start determining the appropriate equipment needed. Equipment is key in transferring the product and its active ingredient to the target pest.
There are a number of considerations to selecting the right equipment. You must assess:
- The recommended type of application: spray, fog, dust, fumigation, etc.
- Your crop location: indoor or outdoor
- Your crop site: size, accessibility, shape, etc.
There are many application equipment types, some being specific to certain products. Sprayers are the most common equipment used in pesticide application. Most biopesticides are applied with hydraulic sprayers and used for mixtures in liquid form. Different sprayer types are available as well. For instance, you would use a handheld sprayer for a small-scale application but opt for a backpack sprayer for a medium-scale application when mobility is required. For large-scale, outdoor agriculture, boom sprayers are used, which consist of long horizontal arms with multiple nozzles that extend over the crop canopy. Dust can be applied with blowers, while solid biopesticides like granules can be applied with spreader or seeder equipment.
Ultimately, understanding the product and pest will guide your choice of tools, ensuring that the biopesticide is applied efficiently and effectively, maximizing pest control.
Knowledge of technical application parameters
Effectively applying a product and getting optimum use of the equipment demands knowledge of the technical aspects of the application process. These parameters include calibration, pressure, application rate, and selecting the correct equipment elements (such as nozzles), among others.
Technical parameters are necessary not only to maximize the product efficacy while preventing waste but also to avoid damage to the crop and the environment.
What calibration and equipment adjustments are necessary?
Calibration is vital to ensure the biopesticide is distributed evenly and at the right concentration in the target area. This prevents under-application that would be ineffective at controlling the pest and over-application that might damage the crop and would waste money.
Calibrating sprayers
Nozzle selection
Sprayers’ nozzles play a key role in the successful application of a product. They come in various sizes and types, affecting the size and distribution of spray droplets. In turn, this influences coverage and effectiveness. Therefore, to decide which nozzle is the best for your situation, you must consider several factors, including the product type, mode of action, and specific requirements noted on the product’s label.
For example, if you have a fungal biopesticide like Beauveria bassiana that needs to come into direct contact with the pest, you could opt for a fine droplet nozzle. This would maximize contact between the spores and the pest, increasing the probability of infection. Conversely, if you want to spray an herbicide and prevent it from drifting onto your crops, you can use a larger droplet nozzle.
Another important component of sprayers is filters or strainers, which can prevent clogs in the nozzles and ensure an even product application. However, for entomopathogenic nematodes, it is necessary to remove these filters to avoid trapping these organisms.
Pressure and speed settings
Nozzles all work within a defined pressure range. To control droplet size, you need to adjust the pressure accordingly. Higher pressure produces smaller droplets, which provides increased coverage but also increases the risk of drift. Speed settings control the flow rate of the product, which influences the coverage area. Generally, a faster flow rate increases the coverage area but reduces the concentration of product per unit area.
Agitation
Some formulations must be constantly agitated to prevent the active ingredients from settling at the bottom of the tank.
Calibrating other equipment types
For other types of equipment, such as dusters and granule applicators, you must take care of several settings to ensure coverage. These are, for example:
- Flow rate (dusters)
- Drop rate (granules)
- Application depth (granules)
- Etc.
What is the best time and frequency of applications?
Importance of timing
The application timing is important to ensure that the pest is targeted at its most vulnerable stage. This also prevents the product from losing efficacy. Some products are most effective when applied during specific pest stages. For instance, some fungal biopesticides work best on hatching insect eggs or juveniles, some parasitoid wasps only work on eggs, etc.
Environmental conditions like humidity, sunlight and temperature can significantly influence a product’s efficacy. Best practices might suggest applying the product early morning or late evening to reduce the risk of evaporation due to UV rays or to avoid inhibitory high temperatures.
The growth stage of the crop can also influence the timing of application. Some crops are the most vulnerable to pests at a particular stage and should be protected during that time.
Frequency of application
Most biocontrol and biopesticide products do not persist long in the environment and require several applications. Refer to the product label for recommendations on frequency and maintain consistent application intervals. This will ensure that the pest is under control.
As part of an IPM strategy, you can also monitor pest levels to optimize the frequency of treatments, such as with the use of yellow sticky traps. This can help ensure application of the product when it is most needed and reduce unnecessary applications.
By understanding the pest, the product mode of action and formulation, and technical application parameters, you can ensure effective and sustainable pest control. Properly applied biocontrol and biopesticide products not only protect your crops but also support environmental health and agricultural productivity. Always follow product labels and adjust your application strategy based on your pest management needs to maximize results.
- For a more complete training guide on pesticide application, read the Applicator Core Training Manual from the Government of Nova Scotia.
