Factors Affecting Seed Germination and Sodium Chloride

Germination

• A seed contains all the energy it needs to grow inside, but it needs a little push. In order for a seed to germinate, it needs oxygen, the correct temperature, water and nutrient-packed soil. If any of these needs are compromised, the seed may germinate slower or not at all. If sodium chloride is present, it will inhibit the movement of water into the seed. Sodium chloride is also toxic to the seed and enters through osmosis. When continuously exposed to sodium chloride, a plant will have stunted growth. This is particularly dangerous for crops as it reduces their yield.

Causes

• Sodium chloride seeps into the soil through several means. Naturally, the minerals in the soil release it over time. The more the salt builds up, the more dangerous it becomes to plants. Run-off from oceans releases salt into the soils and spreads farther inland. Humans can also introduce sodium chloride into the soil. In winter, salt is used to melt ice on paved surfaces. Cars kick up the salt, spreading it onto the land and into the soil. Irrigation brings water that may already contain sodium chloride inland, affecting more soil.

Places Affected

• No part of the United States is safe from sodium chloride in soil. Dry, arid areas have a buildup of salt at the soil surface due to lack of rainfall. Rainwater pushes the salt deeper into the ground in a process called leaching. With little rain in dry areas, the salt remains. Areas that do receive rain still have sodium chloride in the soil. Places with heavy winters, such as the Northeast, use salt to routinely remove ice from roadways, which seeps into the soil. Coastal areas contend with salt from the oceans. Rainwater contains traces of sodium chloride, as well.

Cure

• Leaching is the process where water pushes the salt, and other chemicals, deeper into the ground where it does not reach the roots of the plants. Over-watering dry land will do the same thing and should be performed on dry soil with high saline levels before planting seeds and a few times during the growing season. To aid in the leaching process, gypsum can be used. Apply 50 pounds of gypsum for every 1,000 square feet of affected soil. The gypsum mixes with the sodium chloride to produce sodium sulfate, a chemical that is water-soluble and leaches quickly.

Plants Affected

• All seeds, regardless of type, are affected by salt during germination. The amount of salt varies by plant. For example, a bean plant will have reduced growth with 960 Total Dissolved Salts (TDS) while the sugar beet is more salt-resistant with 5,570 TDS required to harm the plant. While some plants are salt-tolerant, they are still susceptible during germination. Germinate seeds indoors, if possible, before planting them in saline soils outdoors.