Resistance screening of uncharacterized Lupinus angustifolius accessions towards Fusarium oxysporum f. sp. lupini

Lupins, which belong to the family of fabaceae, are plants with a high nutritional potential due to their high protein content, symbiotic nitrogen fixation and environmental adaptability. Yet, plant pathogens including Fusairum oxysporum f. sp. lupini are a considerable problem in lupin cultivation as they can cause considerable yield reduction. To find Lupinus angustifolius accessions with enhanced resistance towards Fusarium infection, we screened 20 yet uncharacterized accessions in a root infection assay. The infected roots were harvested four days post inoculation, followed by total DNA extraction. The rate of infection was estimated by calculating the relative amount of lupin and fungal DNA based on the respective qPCR cq-values. After screening of all 20 accessions, we identified L26 as the most resistant and L49 as the most susceptible accession. To verify this, infection assays of a longer time period of 15 days were performed with these two accessions. The initial results were confirmed as more severe symptoms were observed on L49. To better characterize the infection dynamics, a time series of the infection process was set up and infected roots were evaluated after one, two three and four days. These results showed that already after two days post inoculation there is a significant difference regarding infection levels between L26 and L49. Further characterizations will provide valuable information on the genes responsible for the different resistance levels.