ion toxicity threshold
noun phrasePronunciation: /ˈaɪən tɑːkˈsɪsɪti ˈθreʃˌhoʊld/
The critical concentration of specific ions (such as sodium or chloride) at which cellular damage occurs and plant growth is significantly inhibited. This threshold varies among species and developmental stages, determining salinity stress tolerance limits.
Plain English
The maximum level of harmful ions a plant can tolerate before damage and reduced growth occur.
Etymology & History
Usage
"Wheat varieties exceed the ion toxicity threshold when soil salinity surpasses 8 dS/m, resulting in leaf necrosis."
Style guide notes: Specify the ion type (sodium, chloride) and measurement unit (dS/m, mM) when citing thresholds.
Also known as
Related Terms
Frequently Asked Questions
Why do different plant species have different ion toxicity thresholds?
Genetic variation in ion transport proteins, compartmentalization capacity, and antioxidant systems creates species-specific salt tolerance differences.
Can ion toxicity thresholds change during plant development?
Yes, seedlings typically have lower thresholds than mature plants, and reproductive stages are often more sensitive than vegetative growth.
Why Test Candidates on This?
Essential for evaluating crop salinity tolerance and predicting growth responses in saline environments.
Required skill level: Mid