QTL Mapping and a Transcriptome Integrative Analysis Uncover the Candidate Genes That Control the Cold Tolerance of...

Area of Science:

• Plant genetics and breeding
• Crop science
• Molecular biology

Background:

• Chilling injury from low temperatures significantly impacts maize (Zea mays L.) seedling growth.
• Current maize germplasm lacks sufficient resources for enhancing cold tolerance.
• Wild relatives like Z. perennis and T. dactyloides possess strong cold tolerance.

Purpose of the Study:

• To identify and introduce genes/QTLs conferring cold tolerance to maize.
• To improve the cold tolerance of cultivated maize varieties.
• To provide a foundation for developing maize with enhanced low-temperature stress resistance.

Main Methods:

• Utilized a genetic bridge with Z. perennis and T. dactyloides to create a cold-tolerant maize introgression line (MIL)-IB030.
• Employed forward genetics and weighted gene co-expression network analysis to locate candidate genes.
• Conducted phenotypic, genotypic, gene expression, and functional verification analyses.

Main Results:

• Identified two candidate genes on MIL-IB030 that control relative electrical conductivity.
• These genes were found to positively regulate cold tolerance in the maize introgression line.
• Demonstrated the potential of these genes for improving cold tolerance in cultivated maize.

Conclusions:

• The identified genes offer a viable strategy for enhancing maize cold tolerance.
• This research provides a practical approach for mining and introducing valuable genes/QTLs.
• Establishes a theoretical and practical basis for improving maize against low-temperature stress.