Discovering susceptibility genes to rhizoctonia solani in rice as breeding targets for sheath blight disease resistance
Rice is a main staple food providing more than 50 percent of the world’s calories intake. However, grain yield and quality are drastically reduced by the sheath blight disease (ShBD), the second most important disease. ShBD is caused by the soilborne, necrotrophic fungal pathogen, Rhizoctonia solani. No rice germplasm providing complete resistance is available, preventing improvement of cultivated rice varieties. Generally, dominant resistance genes are used to generate resistance to pathogens. However, these narrow-spectrum genes can be easily overcome by pathogens. Therefore, the best approach to acquire broad-spectrum resistance is to employ altered susceptibility genes (S genes). S genes encode susceptibility factors, facilitate pathogen infection and support compatibility. The molecular mechanisms underlying susceptibility to R. solani are largely unknown. Recently, it has been recognized that necrotrophic pathogens have a short biotrophic phase during infection. In “RiZeSisT” -Rice rhiZoctonia reSisTance-  I will identify rice S genes that are essential to establish the early (biotrophic) infection of R. solani. I will exploit mutated (incompatible) S gene(s) to generate resistance to ShBD. After this project we will generate non-GMO mutants for improving elite varieties for broad-spectrum resistance to ShBD.
 KeyGene acts at the forefront of new technologies and traits to support the development of new and improved crops. Executing “RiZeSisT” at KeyGene, will enable me to use cutting-edge technologies, bioinformatics & data science expertise and plant-based trait platforms to discover the S genes. This is an innovative strategy that has not been used for this pathosystem. Furthermore, there is a high chance to translate my obtained knowledge to generate resistance to R. solani in additional relevant crops as maize, wheat, barley or soybean. The results of “RiZeSisT” will contribute to meet food security needs for our growing population.