Screening Oat Genotypes for Tolerance to Salinity and Alkalinity.

Area of Science:

• Agronomy
• Plant Physiology
• Genetics

Background:

• Salinity and alkalinity pose significant threats to oat cultivation worldwide.
• Developing efficient screening methods is crucial for breeding salt- and alkali-tolerant oat varieties.

Purpose of the Study:

• To establish reliable methods for screening oat tolerance to salinity and alkalinity at germination and adult stages.
• To identify oat genotypes exhibiting tolerance to salt and alkali stress.

Main Methods:

• Four experiments were conducted using varying salt and alkali concentrations for germination and growth stages.
• Genotypic screening of 248 and 262 oat genotypes was performed.
• GGE biplot analysis was utilized for data interpretation; a plastic cone-container system was employed for adult plant screening.

Main Results:

• Optimal screening concentrations were determined: 68.5 mmol L^-1 salt and 22.5 mmol L^-1 alkali for germination.
• Optimal treatments for adult plants: 150 mmol L^-1 Na₂SO₄:NaCl (1:1) for salinity and 75 mmol L^-1 Na₂CO₃:NaHCO₃ (1:1) for alkalinity.
• No significant correlation was found between germination and adult stage tolerances or between salt and alkali tolerance. However, three lines showed tolerance at both stages and to both stresses.

Conclusions:

• Developed effective and cost-efficient screening methods for oat salinity and alkalinity tolerance.
• Identified distinct physiological responses to salt (water absorption disruption) and alkali (chlorophyll reduction) stress.
• Highlighted the need for stage-specific and stress-specific screening in oat breeding programs.