Redox-engineering enhances maize thermotolerance and grain yield in the field

Area of Science:

• Plant Biotechnology
• Crop Science
• Stress Physiology

Background:

• Rising global temperatures and populations increase demand for climate-resilient crops.
• Maize (Zea mays) is vulnerable to heat stress, impacting yield and food security.
• Developing heat-tolerant maize is crucial for sustainable agriculture.

Purpose of the Study:

• To investigate the potential of Arabidopsis thaliana glutaredoxin S17 (AtGRXS17) for enhancing maize thermotolerance.
• To assess the impact of AtGRXS17 expression on maize yield and reproductive success under heat stress.
• To understand the molecular mechanisms underlying AtGRXS17-mediated heat tolerance in maize.

Main Methods:

• Constitutive ectopic expression of a heterologous AtGRXS17 gene in maize.
• Evaluation of thermotolerance through physiological and biochemical assays under controlled and field conditions.
• Analysis of heat stress-associated gene expression and protein damage.

Main Results:

• Transgenic maize lines expressing AtGRXS17 exhibited enhanced thermotolerance.
• Significant protection against protein damage was observed in AtGRXS17-expressing maize.
• A sixfold increase in grain yield was recorded under heat stress field conditions compared to controls.
• Improved pollen germination and ovule fidelity were noted during reproductive stages under heat stress.

Conclusions:

• Ectopic expression of AtGRXS17 confers significant thermotolerance in maize.
• AtGRXS17 enhances maize resilience through improved chaperone activity and gene expression modulation.
• This strategy offers a viable approach for improving crop yields in a warming climate.