TaCol-B5 modifies spike architecture and enhances grain yield in wheat.

Area of Science:

• Plant genetics
• Agricultural science
• Molecular biology

Background:

• Wheat grain yield is significantly influenced by spike architecture.
• Understanding the genetic basis of spike development is key to improving crop yields.

Purpose of the Study:

• To identify and characterize the gene responsible for the number of spikelet nodes per spike in common wheat.
• To investigate the function of the identified gene in regulating wheat yield.

Main Methods:

• Map-based cloning was employed to isolate the target gene.
• Gene expression analysis and functional studies were conducted using transgenic wheat plants.
• Protein phosphorylation assays were performed to understand gene regulation.

Main Results:

• The gene TaCOL-B5, encoding a CONSTANS-like protein, was successfully cloned.
• Overexpression of a dominant TaCol-B5 allele without the B-box region increased spikelet nodes, tillers, and spikes, leading to enhanced grain yield.
• Allelic variations in TaCOL-B5 affect protein phosphorylation by TaK4, influencing its function.

Conclusions:

• TaCOL-B5 plays a critical role in determining wheat spikelet number and consequently grain yield.
• The TaCOL-B5 allele identified is prevalent in emmer wheat but scarce in modern cultivars, suggesting potential for breeding improvements.