Tetrazolium (TZ) Test
Duration: 2 days
The tetrazolium test gives an estimate of warm germination results within two days. It can also be used for small-seeded species in determining the viability of ungerminated seed at the end of the germination period.
Tetrazolium (TZ) Test
Test Details
For the stand-alone TZ test two reps of 100 seeds are placed between moist brown paper towels or blotter paper overnight. The next day the seeds are pierced, cut in half, or left whole (depending on species) and placed in TZ solution. After a short period of time, the seeds are examined for staining patterns. The tetrazolium test can also be used to detect frost damage, estimate vigor, or diagnose seed lot problems.
Iowa State University Laboratory Seed Testing Price List
Prices effective September 2022.
- Treating seeds cost per sample will be less depending on the number of samples.
- Testing by ISTA or Canada Rules (M&P) may require an extra charge.
| Crop** | Standard Germination | Purity Test | Noxious Exam | Tetrazolium (TZ) |
|---|---|---|---|---|
| Corn | $16 | $18 | $18 | $38 |
| Soybeans | $16 | $18 | $18 | $32 |
| Industrial Hemp | $25*** | $18 | $12 | Hourly |
| Cereals, Millet, Sorghum, Buckwheat, Flax, Sunflower, Cotton | $18 | $14 | $12 | $34 |
| Small-Seeded Legumes | $20 | $17 | $12 | $40 |
| Vegetables 1, Flowers 1 | $20 | $17 | $12 | $40 |
| Vegetable 2, Flowers 2, Herbs, & small-seeded species | $25 | $17 | $12 | $40 |
| Grasses: Category 1 | $25 | $25 | $21 | $40 |
| Grasses: Category 2 | $35 | Hourly | Hourly | Hourly |
| Grasses: Category 3 | $35 | $27 | $21 | Hourly |
| GRASS MIXTURES | $35/species | Hourly | Hourly | Hourly |
| Tree, Shrub, Weeds | $35 | Hourly | Hourly | Hourly |
** Mixtures, dirty, and/or low quality samples are subject to a $50.00/hour charge.
*** Significant ungerminated seeds at the end of a germ test are subject to an hourly charge.
Other Tests
| Test | Price |
|---|---|
| Sand Germination | $22 |
| Iowa Tray Cold Test | $17 |
| Accelerated Aging | $17 |
| Saturated Cold Test | $27 |
| Oven Moisture | $18 |
| Instrument Moisture | $10 |
| Bleach Test | $18 |
| Fast Green Test | $24 |
| Seed Count | $10 |
| Test Weight | $10 |
| Seed Treatment | $10 |
| Hourly Charge | $60 |
Other tests available on request – see below for misc. pricing / notes.
SMALL-SEEDED LEGUMES:
- Alfalfa, Clover, Prairie Clover, Sweet Clovers, Crownvetch, Guar, Lespedeza, Trefoil,Vetch, Hairy Vetch
GRASS CATEGORIES:
- Category 1: Brome grass, Fescue, Orchardgrass, Ryegrass (without fluorescence test)
- Category 2: Indiangrass, Prairie Cordgrass, Indian Ricegrass, Alkali Grass, Prairie Dropseed, Sand Dropseed, Lovegrass, Switchgrass, Bluestems, Reed Canarygrass, Gramas, Buffalograss, Creeping Foxtail Wheatgrass spp., Sporobulus spp., Stipa spp., Sugarcane, Teff, Three-awns
- Category 3: Bentgrass, Bluegrass, Buffalograss, Redtop, Timothy, Bluejoint, Juncus spp., Junegrass, Purpletop, Pennisetum
VEGETABLE CATEGORIES:
- Category 1: Vegetable species not in Category 2
- Category 2: Beet, Sugar Beet, Swiss Chard, Carrot, Celery, Chickpea, Lentil, Lettuce, Parsnip, Pepper, New Zealand Spinach, Peanut
FLOWER CATEGORIES:
- Category 1: Flower species not in Category 2
- Category 2: Alyssum, Begonia, Geranium, Hollyhock, Ipomoea, Lathyrus, Lobelia, Lupine, Malva, Petunia , Gentiana, Birdhouse Gourds, Partridge Pea, Sidalcea, Penstemon
How is testing invoiced and paid for?
- The report of analysis has the fee listed as well as test results, but payment is not made from the report. A billing statement will be sent at the end of the month, but payment isn’t made from this either. Finally, Iowa State University Accounts Receivable will mail an invoice and payment is made from that invoice.
- Payment is normally made by check as we don’t accept credit cards.