The salinity of soil directly affects ryegrass' natural ability to absorb nutrients. Minimal amounts of salt won't directly harm the plant and may in fact aid the plant in osmosis in rare cases. In large amounts, iodized salt will starve a plant and make the soil uninhabitable for future farming.
Soil must have soluble salts in order to aid the plant in obtaining nutrients like those found in fertilizers. Iodized salt affects plants differently. Its ability to block both nutrition and water from the roots will often stress plants to the point where they are unable to handle other environmental stresses, such as disease or cold.
The intrusion of salts within the soil can produce symptoms similar to those caused by drought. Stunted growth and wilted organs within the plant are common. Root systems will weaken as a further consequence. As the symptoms progress plants will become increasingly susceptible to insect, fungal and weed threats.
Coastal pastures in particular are commonly threatened by the salinity of the saltwater so close to their growing environments. Although not all plants will be affected, pastoral grasses like rye grass can become extremely dehydrated despite large amounts of water present within the soil.
Some plants have a natural tolerance to salt, including the iodized variety, making them more suitable to such soils. Bermuda grass pastures and hayfields in particular are highly likely to recover from the possible devastating effects of salted soils. This makes them suitable replacements for farmers who live within areas with high salinity. Large quantities of rainfall and irrigation can definitely aid in the recovery process by draining the soil of salts.
Healthy plants with strong support systems will not necessarily die from iodized salt intruding to their soil. Over time, if the salts continue to build within the habitat the risk of nutrient deficiency and dehydration will continue to increase. This leaves ryegrass plants also susceptible to environmental threats, which can become lethal to the weakened plant.