Maize Crops Under Rising Temperatures: Bacterial Influence on Biochemical and Lipidomic Changes Induced by Heat

Area of Science:

• Plant Science
• Microbiology
• Biochemistry

Background:

• Rising global temperatures impact plant performance, causing reduced growth and compromised membrane integrity.
• Plant growth-promoting bacteria (PGPB) offer potential for enhancing crop thermotolerance, but mechanisms are unclear.

Purpose of the Study:

• Investigate the effects of PGPB inoculation on Zea mays (maize) under control and heat stress conditions.
• Explore the morphometric, biochemical, and lipidomic changes induced by PGPB under heat stress.

Main Methods:

• Maize seeds were inoculated with thermotolerant PGPB strains (Pantoea sp.) and subjected to control (26°C) and heat stress (36°C) conditions.
• Evaluated plant performance using morphometric, biochemical (oxidative stress markers), and lipidomic analyses.

Main Results:

• Heat stress reduced germination by 35.9% and increased oxidative stress markers (LPO, SOD, GPx).
• Pantoea sp. inoculation improved heat-stressed seed germination by 15%, enhanced growth (shoot +28%, root +17%), boosted antioxidant enzymes (CAT, APx), and reduced membrane damage by 65%.
• Lipidomic analysis showed PGPB inoculation mitigated heat-induced alterations, reducing triacylglycerol and preserving key lipids, leading to profiles similar to control plants.

Conclusions:

• PGPB inoculation, specifically with Pantoea sp., significantly enhances maize thermotolerance.
• This strategy improves plant growth, antioxidant capacity, and membrane integrity under heat stress.
• PGPB represent a viable approach to improve crop resilience in the face of climate warming.