As living organisms, biocontrol products are subject to variability caused by various factors. There are many steps along the way where quality of biocontrol agents can be affected, starting at the insectary where they are mass-reared, to the crop where they are released.
Biocontrol producers are constantly challenged to provide a consistent and reliable supply of high quality natural enemies. To meet this demand, regular and extensive quality control (QC) checks are done at the supplier level to ensure products meet certain standards before they are shipped to the customer.
Yet, it often takes several days before products arrive at the grower and are released into the greenhouse.
During shipping, uncontrolled packaging, transport and storage conditions may compromise the quality of the biocontrol agents and their subsequent performance in pest control.
SHIPPING AND STORAGE FACTORS CAN AFFECT EFFICACY
For example, temperature extremes, condensation from ice packs, restricted oxygen supply, unnatural high population densities, and extended shipping and storage times are all factors that can negatively impact the biocontrol agents. This will have a direct impact on efficacy and may result in failure to control the target pest.
Growers should always open packages upon arrival to provide a better environment for biocontrol agents and to detect potential problems related to shipping conditions; and biocontrol agents should be released into the crop as soon as possible.
In an ideal situation, growers should perform quality checks on every biocontrol shipment they receive so that release strategies can be modified if necessary.
Presently, few growers regularly perform quality checks on the biocontrol products they receive. Doing these checks is perceived as time-consuming and until now, there were no standardized procedures available.
QUICK, EASY QC PROTOCOLS FOR VARIOUS PRODUCTS
Recognizing the needs of growers and the biocontrol industry for better guidelines, a collaboration of Flowers Canada Ontario; the Association of Natural Biocontrol Producers; IPM Florida and the USDA; National Institute of Food and Agriculture, Extension IPM funded a project at the Vineland Research and Innovation Centre to collate and develop easy and quick QC protocols for various biocontrol products.
The protocols are now available in the recently completed “Grower guide: Quality assurance for biocontrol products” which can be found at http://vinelandresearch.com/sites/default/files/grower_guide_pdf_final.pdf .
This guide contains tests that growers can perform on-site, requiring only a hand lens or a simple microscope. Many of the materials used in the tests can be obtained from companies selling entomological supplies, or made in-house using cups, screening materials and a glue gun.
The guide is illustrated with detailed pictures for different steps and test set-ups.
In general, we recommend when receiving a biocontrol shipment to:
- Open the package and check for condensation, a smell of fermentation and content temperature.
- Look for movement in each individual container: biocontrol agents walking around or (when applicable) flying.
- Keep some of the materials for QC testing, release the rest in the crop according to the IPM program.
- If a problem is detected, adjust future release rates to ensure good control of the target pest.
- Predatory and food mites Predatory and food mites
- Common tools Common tools
- Helpful guide now available Helpful guide now available
- Close inspection Close inspection
TESTS TO ASSESS SHIPMENT QUALITY
The guide covers most commonly sold biocontrol agents and gives a description of the product, a test to assess the quality of the shipment once received, and differences between males and females (if visible and/or applicable). The methods will provide growers with a good indication of the total number of living biocontrol agents in the container.
Through observation and handling of biocontrol agents, the user will develop a “feel” for the health of the product. The guide also describes signs of activity in the crop to monitor biocontrol agents after release and assess their effectiveness.
A few things to keep in mind when doing these tests:
- Based on QC tests at the producer, more biocontrol agents might be present in the container than stated on the label to compensate for low emergence or high mortality.
- If both adult females and males are present, sex ratio should be at least 40-45 per cent female.
- Record-keeping is a must. It is important to take notes of species name, packaging type/size, date received, company batch number, date tested, method used, number of samples, number of biocontrol agents counted and any other observations on the appearance and performance of
- the product.
- The small number of samples recommended in the guide tends to underestimate the total number of biological control agents in the package. If the tests indicate that the package contains less than 70 per cent of the expected number of living biological control agents, a problem should be suspected.
Quality assessments by end-users provide information that allows producers to monitor product quality right through to the point of release and, if needed, to refine production methods to ensure they continue to deliver high quality products.
Thanks to Erik Glemser and Ashley Summerfield for their work gathering information and editing this guide, the companies and people that contributed pictures illustrating the tests, and several growers and industry representatives for their valuable feedback.