Drought-tolerant potato development using CRISPR/Cas9 genome editing of SAL1 and ERA1 genes

Overview

This project aims to improve drought tolerance in cultivated potatoes by using genome editing to target and reduce the expression of two known negative drought regulators: SAL1 and ERA1. The research focuses on the potato variety Diacol Capiro, which is drought susceptible, and seeks to generate improved lines with enhanced resilience to water deficit conditions. By modifying these conserved regulatory genes, the work addresses a critical challenge for agriculture under climate-related water stress, with potential improvements in crop yield stability and food security.

The approach is grounded in evidence from both monocot and dicot species, where manipulation of SAL1 and ERA1 has consistently produced drought-tolerant phenotypes. This suggests a conserved function across angiosperms and supports the feasibility of applying the same strategy to potatoes.

Technical specifications

Target genes and mechanism:

• SAL1 and ERA1 function as negative regulators of drought response in plants
• Reducing or blocking their expression activates abscisic acid (ABA)-responsive gene expression
• ERA1 modification enhances drought response through stomatal regulation while maintaining wild-type-like leaf growth and increasing primary root growth
• Previous validation in Arabidopsis, wheat, rice, and soybean showed statistically significant drought tolerance improvements

Editing approach:

• CRISPR/Cas9 genome editing using a T-DNA binary vector
• Cas9 paired with U6 promoters and scaffold guide RNAs
• Targeting predicted open reading frames of potato SAL1 and ERA1 homologues
• Transformation events confirmed before drought tolerance testing

Validation method:

• In vitro PEG-induced water deficit stress assay
• Designed to assess drought tolerance enhancement in controlled conditions
• One-year timeframe for transformation, confirmation, and validation

Technology readiness level

This research is at an early experimental stage, with feasibility supported by prior demonstrations in other crop species. The project is designed as a one-year proof-of-concept study to generate and validate initial transformation events in the Diacol Capiro potato variety. Following successful in vitro validation, further field trials and regulatory development would be needed before commercial deployment.