When it comes to fall-seeded cereals, timing is everything. Decisions related to seed quality, inventory management, conditioning, sales, and planting often need to be made quickly, especially as the fall seeding window approaches.
Tetrazolium Chloride Vigour (TZV) testing is a valuable tool that helps seed growers, retailers, seed cleaning plants, and producers assess seed viability and seed vigour rapidly providing critical information when time-sensitive decisions are required.
What is Tetrazolium Chloride Vigour (TZV) Testing?
Tetrazolium testing is a rapid biochemical method for evaluating seed viability and vigour, in which living, respiring seed tissues absorb colorless Tetrazolium Chloride (TZ) and reduce it to a red compound called formazan; healthy tissues stain bright red while dead or damaged tissues remain unstained or stain unevenly, enabling trained analysts to identify viable tissues, estimate seed vigour, and support seed quality control decisions.
During evaluation:
- Uniformly stained seeds are considered to have high vigour.
- Seeds with tissue poorly stained or essential structures not viable are considered to have low vigour.
Unlike the traditional vigour test, which may require 12-14 days to complete, Tetrazolium Chloride Vigour (TZV) testing can provide results within 24 to 48 hours. Tetrazolium testing is often used to complement germination by providing a percentage of viable seedlings. We are now able to assess vigour using a method approved by the International Seed Testing Association (ISTA).
The Value of Tetrazolium Chloride Vigour (TZV) Testing in Fall-Seeded Crops
Fall-seeded cereals present unique challenges. There is often limited time between harvest, conditioning, seed sales, and planting. Waiting for conventional germination and traditional vigour results can delay important decisions during a narrow planting window.
Tetrazolium Chloride Vigour (TZV) testing provides an early indication of seed quality, allowing stakeholders to:
- Evaluate seed lots quickly
- Make informed inventory decisions
- Support seed marketing and sales activities
- Estimate planting potential before seeding begins
- Identify potential quality concerns sooner
While the Tetrazolium Chloride Vigour (TZV) test does not replace a germination test, it can be used as a rapid vigour test; it can provide valuable information while additional testing is underway.
Fall-seeded cereals are frequently planted soon after harvesting; a rapid vigour and viability assessment can be especially valuable when making management and marketing decisions.
Specific Benefits for Winter Wheat and Winter Triticale
Winter wheat and winter triticale often exhibit varying levels of dormancy shortly after harvest. In these situations, a standard germination test is often repeated using additional dormancy breaking techniques which further delay the test. A Tetrazolium Chloride Vigour (TZV) test can determine the true viability of the seed lot much faster and can be used in conjunction with the germination test to separate dormant seeds from dead seeds.
This information can provide greater confidence when evaluating freshly harvested winter wheat and winter triticale intended for fall planting and can help explain discrepancies between viability and germination results.
Identifying Damage Before It Becomes a Problem
In addition to determining viability, tetrazolium chloride vigour (TZV) testing can provide insight into damage that may affect seed performance.
Experienced analysts may identify evidence of:
- Heat stress
- Mechanical damage from harvest or handling
- Seed structures affected by pathogens
- Immature seed development
- Weathering damage
This information can help explain reduced performance potential and support decisions around seed conditioning, storage, and use.
Successful establishment is critical for fall seeded cereals. Understanding seed viability allows growers and seed suppliers to make more informed decisions regarding seeding rates and stand establishment expectations. By understanding the quality of a seed lot before planting, growers can better manage risk and improve confidence heading into the growing season.
When Should Tetrazolium Chloride Vigour (TZV) Testing Be Considered?
Tetrazolium chloride vigour (TZV) testing is particularly useful when:
- Fall planting deadlines are approaching
- Freshly harvested seed is being evaluated
- A rapid viability estimate is needed
- Germination results are pending
- Seed lots have experienced challenging harvest or storage conditions
For fall-seeded cereals, Tetrazolium Chloride testing provides a valuable snapshot of seed vigour and viability when timing matters most. While it does not replace a germination test, it offers rapid insight into seed quality and helps growers, seed plants, and seed suppliers make informed decisions around planting, seeding rates, inventory management, and crop establishment before the fall seeding window closes.
If you are growing fall seeded crops and looking for rapid insight into seed quality, consider investing in a Fall-Seeded Performance Package for hybrid fall rye, winter wheat and winter triticale.
Fall-Seeded Performance Package
- Complete Germination diagnostic
- Tetrazolium chloride vigour (TZV) test
- Fungal screen
Questions? Contact our lab directly at 1-877-420-2099 support@2020seedlabs.ca
