BREEDIT: a multiplex genome editing strategy to improve complex quantitative traits in maize.

Area of Science:

• Agricultural Science
• Genetics
• Biotechnology

Background:

• Global food security and climate change adaptation are critical challenges for 21st-century agriculture.
• Conventional crop improvement methods are nearing their limits, necessitating advanced breeding techniques.
• Complex traits like yield and drought tolerance are controlled by multiple genes, posing a challenge for traditional breeding.

Purpose of the Study:

• To introduce BREEDIT, a novel gene discovery pipeline for accelerating plant breeding.
• To combine multiplex genome editing with crossing schemes to improve complex agricultural traits.
• To identify gene modifications that enhance crop yield and stress tolerance.

Main Methods:

• Utilized CRISPR/Cas9 technology for multiplex genome editing of 48 growth-related genes in maize (Zea mays).
• Generated a diverse collection of over 1,000 gene-edited maize plants.
• Applied crossing schemes to analyze gene interactions and trait improvement.

Main Results:

• Gene-edited maize populations showed significant increases in leaf dimensions: 5%-10% increase in leaf length and up to 20% increase in leaf width.
• Identified specific gene families where edits in subsets of genes were associated with enhanced traits.
• Demonstrated the ability to narrow down the gene space for targeted trait improvement.

Conclusions:

• The BREEDIT pipeline effectively accelerates the identification of gene modifications for complex traits.
• Multiplex genome editing combined with crossing schemes is a powerful approach for crop improvement.
• BREEDIT offers a rapid method to generate mutant collections for identifying promising genetic targets in breeding programs.