Drought tolerance in canola through modulating the Kanghan (KH) gene family

Project Summary

Background

Improving crop tolerance to drought is essential for maintaining yield stability under the continued threat of climate change. It is also a key factor for achieving sustainability in agriculture by saving water resource usage and expanding arable land areas for crop production. Drought tolerance, like many other important agronomic traits, is controlled by quantitative trait loci (QTL). Molecular breeding focusing on monogenic variations and/or transgenic intervention of single gene has so far achieved very limited success in the development of effective drought tolerance in crops. This project builds on the discovery of a gene family whose members collectively regulate drought tolerance trait in canola.

Purpose

A gene family, Kanghan (KH), underpinning drought tolerance was discovered though QTL analysis of Arabidopsis ecotypes, and homologs of the KH gene family were identified from Brassica napus. Growth chamber assessment demonstrated that RNAi suppression of the KH gene family in canola leads to drastically improved drought tolerance.

This project will conduct confined field trials to assess water-limited yield potential of the transgenic canola lines. To assist the adaptation of this technology in breeding and to facilitate regulatory approval of the novel trait, this project will also conduct CRISPR gene editing of the KH genes in canola to generate knockout lines with improved drought tolerance.

Objectives

The discovery of the critical role of KH genes in drought tolerance provided a technological basis for improving canola yield stability under the persistent challenge of moisture shortage in the Prairies. The primary objective of this project is to demonstrate the KH technology under field conditions so it will be adopted by industry programs for drought tolerance trait breeding. Since modulating KH gene may be achieved by CRISPR for targeted gene knocking-out, the second objective of this project is to generate CRISPR lines disrupting KH genes in elite canola germplasm for drought tolerance breeding.