Importance of Seed Viability
The viability of seeds or plant material refers to how many seeds or plant material in a lot are alive and capable of developing into plants that will reproduce in the field. For instance, some seeds can live for several years, while others may only live for a few months.
Why is seed viability important?
When seeds or plant material are preserved in the gene bank, it is critical that they can produce plants when put in the field. They must have a high level of viability at the beginning of storage and maintain it throughout. Seeds or plant material with a high initial viability will also store well. The viability of seeds or plant material drops gradually at first, then rapidly as the seeds or plant material ages. It’s critical to understand when this drop begins so that you may take steps to resurrect the accession. Excessive degradation will result in material loss.
How is seed viability tested?
The germination test is the most accurate way to determine seed viability. The germination test is carried out under controlled settings to determine how many seeds will germinate and produce normal seedlings that will mature into reproductively mature plants. Seed germination is influenced by a variety of circumstances. Water availability, temperature, and sunshine are the most critical elements.
The Advisory Committee on Seed Storage of the International Board for Plant Genetic Resources (IBPGR) recommends a minimum of two replicates using 200 seeds (100 seeds per replicate) for the initial germination test of species where a reasonable germination technique is available, provided that germination is above 90%. If not, 200 more seeds must be tested as before, with the total seed viability result taken as the average of the two tests.
There are other tests that may determine the viability of a seed but may take longer than conventional viability testing mechanisms. Some of these tests may include the Chemical test, water seed viability test, floating method, tissue paper roll test among others.
How does seed viability affect the producer/farmer/breeder?
Generally, a seed has both live and dead tissues. Whether or not a live seed can germinate or not is determined by a seed viability test using the aforementioned tests. A viability test also determines whether a seed is alive, metabolically active and has the enzymes required to undergo metabolic changes required for seed germination and development.
Moisture stress, food shortage, severe temperatures, and other factors often result in light, shriveled seed. This is a common occurrence in seeds with poor viability. A viability may be affected due to excessive humidity, warm temperatures, improper storage methods or other reasons. Furthermore, genetic characteristics such as seed hardness, disease resistance, and seed chemical composition also impact germination.
Farmers must verify that their seed is viable, regardless of where it came from. It aids in the protection of the investment and assures the farmer of a satisfactory return. To know more about how seed viability can be tested, achieved and promoted to ensure a safe crop, speak to Gubba for seed storage tips, solutions and more.