Which management step helps mitigate osmotic stress from elevated salts in the root zone?

• A. Increasing fertilization
• B. Leaching salts from root zone
• C. Increasing mowing height
• D. Increasing irrigation water salinity

Answer: (B)

Osmotic stress from elevated salts happens when soluble salts in the root zone raise the soil’s osmotic potential, making it harder for plant roots to take up water even if the soil is moist. The best way to counter this is leaching salts from the root zone: applying extra irrigation water moves soluble salts below the rooting depth, lowering the salinity near the roots and reducing the osmotic draw that blocks water uptake. In practice, this requires adequate drainage and a careful leaching fraction so you flush salts without wasting water or causing runoff. It’s also helpful to manage fertility to avoid adding unnecessary salts and to monitor soil salinity to time leaching appropriately. Increasing fertilization, raising irrigation water salinity, or changing mowing height do not address the salinity near the roots and can worsen the problem.