Antioxidative response of tomato genotypes to late blight infection

Wild species are widely used as potential sources of resistance of tomato to late blight (LB) (causal agent Phytophthora infestans). The biochemical response of wild and cultivated tomato genotypes with different levels of resistance to P. infestans was assessed through the total phenolic and flavonoid content and antioxidative capacity. In total, six genotypes were included in the research ? three cultivated tomato varieties and three wild species. The wild genotypes Solanum pimpinellifolium S 220 and Solanum habrochaites had a significantly lower infection rate compared to the other tested genotypes. After disease assessment on the leaves, biochemical analyses were performed. Grouping of the wild accessions according to principal component analysis (PCA) analysis indicated similar reaction to LB infection. Furthermore, late blight trait is closer to cultivated genotypes. Although the phenolics and flavonoids have high importance in the reaction of tomato plants to late blight infection, these traits are not closely related to wild species and the disease. According to this study, the antioxidative tests that indicate a response of wild species to late blight infection are total antioxidant activity (TAA), ferric-reducing antioxidant power (FRAP) and radical cation scavenging activity (ABTS).