SEMINAR: Plant Biology research seminars

The diseases caused by Turnip mosaic virus (TuMV) decrease the productivity of Brassicaceae crop species worldwide. If available, virus-resistant cultivars can provide an effective method of controlling the diseases TuMV causes. Many new sources of diverse TuMV resistance phenotypes were identified in different lines of B. napus, B. carinata, B. juncea and other Brassica species. In B. juncea, expression of systemic hypersensitive resistance (SHR) was controlled by incompletely dominant resistance gene TuRBJU 01 which was overcome by only one (NSW-3) of ten TuMV isolates tested. In plants with TuRBJU 01, SHR was mainly due to phloem necrosis and presence of xylem occlusions. In B. carinata plants, use of cell deformation and electrolyte leakage differentiated compatible and incompatible plant responses due to TuMV infection before appearance of symptoms. Australian TuMV isolates differed in virulence when inoculated to diverse plant species, and their complete genomes belonged to two different phylogenetic groupings. These findings are of considerable importance for future development of Brassica cultivars resistant to TuMV and development of novel methods to control this virus.