Using Pocket Diagnostic Test Kits
Designed to give growers, technicians and plant health professional’s information about plant health where and when it is needed Pocket Diagnostic Test Kits deliver in-field results. Anywhere along the supply chain including in the field, shadehouse, glasshouse or on the farm disease symptoms can be confirmed in just a few minutes.
Each Pocket Diagnostic Test Kit pack contains the required implements for successfully completing an in-field diagnostic test on plant samples. Collect the symptomatic plant material including fruit, stems, leaves, bark or roots and process as per the instructions contained in each pack.
Simply place 2.5cm² of plant material in the unique ‘bottle and ball’ sample preparation method and shake for only 20-30 seconds (60 seconds for more resistant samples) and the test can be run.
Convenient and easy to use - bringing point of care decision making to your crops.
Preparation makes perfect
Using Pocket Diagnostic test kits is straightforward. However, as with any test procedure, attention to detail will pay dividends. Here are some 'golden rules' to maximise performance and reliability of the tests:
Rule 1: Sample selection
Sample selection is key to achieving a reliable result. Points to note include:
- Don’t use too much tissue (0.2g, or a 25mm square piece of leaf is sufficient)
- Take symptomatic tissue, include if possible the junction between healthy and diseased material
- Don’t use dead tissues
- If sampling a large plant, combine material from several places
- Wash soil off root samples
- Check Keycards for specific information on sampling.
Remember: avoid the temptation to add more sample just 'for good measure'. Too much sample tissue will cause the test device to run incorrectly.
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Rule 3: Sample loading
Start the test by adding two drops of liquid from the extraction bottle. Avoid drawing sample debris or air bubbles into the pipette as these will interfere with the test.
If you don’t see the liquid front moving across the viewing window on the test device, add one more drop – but avoid flooding the device. The correct size of drop is achieved when the pipette is held vertically.
Keep the test device horizontal when loading and running the test.
Remember: don’t add too much sample to the test device. If an air bubble does stop the test running, try squeezing the housing gently to release it.
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Rule 2: Sample preparation
Thorough extraction of pathogen (e.g. virus particles, fungal mycelia) from the tissue sample is essential. In general, the more tough or woody the sample, the more shaking is required.
For example, bark samples should be cut up finely and shaken in buffer for 60 seconds. Leaves with a thick cuticle should be cut or scored before adding to the extraction bottle.
Remember: you can’t 'over shake' the bottle, but insufficient shaking will reduce test performance. |
Some other points to keep in mind:
1. Keep warm
Tests run very slowly below 10°C. If using in cold conditions, warm the test device and buffer bottle in your hand first, or even better, keep them in your pocket before use.
2. Open and use
Once the foil pouch is opened, use the test.
Moisture affects the performance of the kits, so don’t open until you need to use.
3. Be patient
Not all Pocket Diagnostic tests run at the same speed. In general, potato tests run fully within
5 minutes. Other tests can take up to 10 minutes.
4. Ignore late-comers
All Pocket Diagnostic tests run fully in 10 minutes or under. Read the test result no later than 10 minutes, and ignore any changes which occur after this time. |
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How to use the test
- Select sample.
- Cut or tear sample into small pieces and put into bottle.
- Shake firmly for 20 seconds (longer for more resistant samples).
- Draw liquid into pipette.
- Add 2 drops into sample well of test strip.
- Read result after 3-5 minutes. One line is negative result, two lines show positive result.
Baiting Method
How to bait soil, water
and growing media for
Phytophthora & Pythium spp.
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