Thesis: Association of Copy Number Variation with Qualitative and Quantitative Resistance against Leptosphaeria maculans in Brassica napus
My project focuses on association of copy number variation (CNV) with phenotypic traits to characterise the relationship between CNV and resistance to the most devastating pathogen in cultivated Brassica species; Leptosphaeria maculans (blackleg). Initially, re-sequencing of genomes will be carried out for canola cultivars and then phenotypic screening with L. maculans isolates will be performed to look at qualitative and quantitative resistance. Lesion scores will be measured after inoculation on cotyledons and leaves. The genome re-sequencing data from the canola cultivars will be used for CNV detection. Then to discover association between the CNVs and blackleg resistance, genome wide association will be performed. CNV will be validated through amplification of genomic DNA and quantitative real time polymerase chain reaction (qRT-PCR). The results will provide a snapshot of CNVs in canola cultivars and will help with identification of CNVs’ role in blackleg resistance for control of this disease.
Why my research is important
With growing concern about world-wide food shortages and climate change, protecting food crops against pathogens that cause epidemic diseases is more important than ever. Among these pathogens, Leptosphaeria maculans, causal agent of blackleg disease, is responsible for major yield losses of canola in Australia. There is potential for a significant expansion of this crop in Australia once germplasm that demonstrates improved disease resistance becomes available. Nonetheless, little is currently known about the extent of CNV in canola. In addition, CNV detection using re-sequencing is a novel approach by which we can investigate the selection of genomic regions that has occurred through breeding, and further understand the evolution and selection of important agronomic traits. In addition, resolving agronomic limitations through improved germplasm would assist in the stable production of this crop and overcome the current boom bust cycles of canola production associated with disease prevalence and climatic variation.