Lab Testing

Standard Warm Germination

Used to determine how seed will perform under ideal conditions. Seeds are placed on sterile media in a growth chamber set at the ideal temperature and humidity. Seeds are evaluated according to AOSA rules specifying duration of test period and classification of normal, abnormal, and dead seedlings. Results are reported as percent germination, including dormant and hard seed.

Tetrazolium (Tz) Test

The Tz test is a quick test (24 hrs) used to estimate germination and seed lot vigor. Seeds are imbibed with water and then soaked in a solution of tetrazolium chloride. As the seeds respire the tetrazolium chloride reacts changing from a clear color to a red color. Based on the staining patterns, seeds are evaluated into categories of high, medium, and low vigor or dead seed. The Tz test has proven very beneficial in determining mechanical damage in soybeans and sprouting in small grains. MCIA recommends that seedlots should have at least 80 combined high and medium vigor seeds to be considered high vigor seed. This test is available for all field crops.

Accelerated Aging (AA) Test

The AA test is as the name implies a test used to artificially age seeds by exposing them to a stressful environment allowing seed respiration levels to increase. This test can be used to predict storability of a seed lot along with determining the vigor of a seed lot. Seeds are placed in chambers of high temperatures (41 C ) and high humidity for a set period of time. After this stress period, seeds are then germinated under ideal conditions. High quality seeds will produce normal seedlings while low quality seed will deteriorate and produce abnormal or dead seedlings. MCIA recommends that AA germination levels of 80% or better be considered as high vigor seed. This vigor test is available for small grains, soybeans, corn, and dry beans.

Cold Test

The cold test is used to help predict how a seed might perform if planted in cool wet soils common with early spring planting. Seeds are planted in soil with exposure to fungi common in soils, placed in a cold chamber (10 C) for a set period of time, and then transferred to a chamber to grow under ideal conditions. High quality seeds will produce normal seedlings while low quality seed will be unable to survive these conditions and will produce abnormal or dead plants. MCIA recommends that Cold Test germination levels of 75% or better be considered as high quality seed. This vigor test is available for corn, soybeans, and dry beans.

Saturated Cold Test

The saturated cold test is a 10-day extreme vigor test that will help determine if your seed is suitable for early planting. This test mimics chiling shock and low oxygen levels by testing seed in cold, water saturated soil. After 7 days in a cold dark environment, the seed is moved into a light warm environment for 3 days, after which evaluation will take place. This test should not replace a standard cold test, which emulates a typical spring planting environment. However, it does provide a useful estimate of emergence under severe conditions.

This test is designed for the cold, saturated rainfall that could occur once your seeds are planted.

Extended Cold Test

The extended cold germination test is used to determine the seed vigor by stressing the seeds under conditions of cold-water imbibition in a field soil situation. The cold germination test simulates early spring field conditions by exposing the seed to high soil moisture and low soil temperatures. While, very similar to a standard cold test, this test has a longer period of cold temperature stress exposure. The samples are placed in a cold environment set at 10 degrees C for 14 days, then moved into a walk-in germinato set at 25 degrees C for an additional 7 days.

Seed Purity Analysis

The purity test is a physical evaluation of a set amount of seed described by AOSA rules. It is evaluated for the percent pure seed, inert, weed seed, other crop, and other varieties. Results are used to label seed and determine if it is in compliance with certification, state, and federal regulations. MCIA also performs noxious weed seed exams for seed sales in other states or countries as requested. A sample is analyzed for percentages of:

Pure Seed – the crop kind and variety sold.

Other Crop – seed of unintended or inseparable species commonly used in crop production. Seed of other varieties is included in this percentage.

Inert Matter – undeveloped or broken seeds, chaff, dirt, rocks, or other foreign matter.

Weed Seed – seeds of species determined to be weeds including: common weeds, prohibited (none allowed) noxious weeds, or restricted (limited) noxious weeds under State of Michigan Seed Law.

Mechanical Purity

A mechanical purity is a visual analysis of a clean or conditioned seed sample. It is used to represent the seed lot as it is offered for sale and often the basis for a seed tag or label. A sample is analyzed for percentages of:

Pure Seed – the crop kind and variety sold.

Other Crop – seed of unintended or inseparable species commonly used in crop production. Seed of other varieties is included in this percentage.

Inert Matter – undeveloped or broken seeds, chaff, dirt, rocks, or other foreign matter.

Weed Seed – seeds of species determined to be weeds including: common weeds, prohibited (none allowed) noxious weeds, or restricted (limited) noxious weeds under State of Michigan Seed Law.

Fast Green Test

The fast green test is used in seed corn to detect damage to the pericarp (seed coat), has a quick one-day turn around with accurate test results, and provides information about seed vigor. Seeds are soaked in a low contrasting dye, non-toxic to embryos and small seedlings. Any damage to seeds such as cracks or tears in the embryonic axis or seed coat will stain green. Seeds are then evaluated and ranked into three categories of damage – light, medium, and severe. The amount of pericarp damage shown in this test can identify how susceptible a seed lot may be to soil pathogens, pests, and microorganisms.

The test provides useful insight regarding seed conditioning and starter fertilizer. If seed corn is harvested at a higher moisture content, more threshing is required, which can lead to more tearing of the seed coat; this test helps to identify the severity of those tears of the pericarp. If seed has mechanical damage to the seed coat during the conditioning process, this test can help maximize output while minimizing damage to the seed from machinery. Whether using 2×2 or Popup fertilizer, if seed coat damage is severe, fertilizers with high salinity could damage or kill the seed.

Herbicide Testing

Herbicide testing is offered for both Roundup and Enlist varieties. Seeds are tested to quantify the purity level of the genetic trait in seed lots. This test can also be used to determine the purity of conventional varieties. Testing is available for soybeans.

Seed Count Test

As planting equipment and recommendations become more specific, seed counts become more important. MCIA performs seed counts to accurately determine the number of seeds per pound, which is used to calculate the planting rate needed to obtain the desired plant population. This test is available for small grains, soybeans, corn, and dry beans.

Seed Moisture Test

This test is available for most field crops and determines the percent moisture found in the seed sample. It can be very useful for determining whether the seed is at a safe moisture level for storing.

Sand Germination

This test is similar to the typical warm germination, just with sand. Seeds are planted on proper substrata, with a layer of stand over the top.

The sand suppresses the presence of fungi or bacteria that could be on the seed coat.