Capturing ancestral diversity for developing climate ready canola

Project Summary

Overview

Canola (Brassica napus) like many crops has a small genetic foundation which has been further narrowed with continued selection for key quality traits. The long-term sustainability of canola yield relies upon the identification and introduction of novel variation.

Canola was derived from a hybridization event between two related diploid species, Brassica oleracea and Brassica rapa, which are known to be a rich source of variation for agriculturally important traits, in particular for abiotic and biotic stress tolerance. This project intends to exploit this wealth of variation by resynthesizing new Brassica napus lines incorporating phenotypes which would contribute to climate-ready canola lines, resilient to environmental impacts.

By utilizing a high-throughput image based screening system lines with an optimal root system architecture can be identified among the progenitor species. The underlying root system plays a key role in determining the ability of the crop to withstand nutrient and water deficits and potentially to guard against attack by certain pathogens and pests. Increasing the root biomass can also contribute to the level of carbon sequestration offered by the crop.

Genotype data gathered along with the phenotype database will allow regions of the genome that contribute to particular root architectures to be identified and tagged with molecular markers. Newly resynthesized lines will be studied in the greenhouse and field to quantify their ability to contribute to water use efficiency and promising material will be crossed with elite canola lines, capturing the valuable diversity for the canola crop.

Objectives

Specific objectives for this project are:

1. A diverse collection of diploid progenitors will be screened using high throughput imaging to identify suitable variation in root architecture.
2. Develop a quantitative measure of clubroot infection using two-dimensional root imaging. This method will be used to screen material with increased root biomass identified in objective 1.
3. Identify genetic basis of identified variation (to determine loci controlling traits of interest).
4. Develop new resynthesized B. napus lines from the most promising material identified in objectives 1 and 2 (for improved canola root architecture). These lines will then be crossed to elite material to generate pre-breeding material.
5. Greenhouse and Field testing of improved germplasm under multiple environments.

Potential impact

The project will identify new diversity that ensures the long term sustainability of the canola crop. It will target traits that have been linked to generating a more environmentally aware and climate responsive plant, through increasing yields while reducing further use of limited resources (water), and chemical inputs (fertilizer) known to contribute to the current negative climate trends.

The identification of novel sources of resistance to clubroot and a method for rapid and robust screening of new germplasm should have early economic benefits for the industry and producers, where is has been estimated that up to 30% of the yield can be lost due to damage incurred through clubroot.

The germplasm screened and the associated information generated, including both phenotype and genotype data, will form a significant resource for breeders and academics, which will allow the continued improvement of canola and contribute to the long-term economic and environmental sustainability of canola.