Eggplant and related species are promising genetic resources to dissect the plant immune response to Pseudomonas syringae and Xanthomonas euvesicatoria and to identify new resistance determinants

Abstract

Summary The apparent lack of durability of many resistance (R) genes highlights the need for the constant identification of new genetic sources of resistance for the breeding of new disease‐resistant crop cultivars. To this end, we screened a collection of accessions of eggplant and close relatives for resistance against Pseudomonas syringae pv. tomato (Pto) and Xanthomonas euvesicatoria (Xeu), foliar plant pathogens of many solanaceous crops. Both pathogens caused substantial disease on most genotypes of eggplant and its relatives. Promisingly, however, some of the genotypes were fully or partially resistant to either of the pathogens, suggesting the presence of effective resistance determinants in these genotypes. Segregation of resistance to the growth of Xeu following infiltration in F2 progeny from a cross of a resistant and susceptible genotype suggests that resistance to Xeu is inherited as a multigenic trait. With regard to Pto, a mutant strain lacking all 28 functional type III secreted effectors, and a Pseudomonas fluorescens strain expressing a P. syringae type III secretion system (T3SS), both elicit a strong cell death response on most eggplant lines. Several genotypes thus appear to harbour a mechanism for the direct recognition of a component of the T3SS. Therefore, eggplant and its close relatives are promising resources to unravel novel aspects of plant immunity and to identify new candidate R genes that could be employed in other Solanaceae in which Xeu and Pto cause agriculturally relevant diseases.

Nematicidal Properties of Methanolic Extracts of Two Marine Algae against Tomato Root-Knot Nematode, Meloidogyne incognita

“…Crude proteins in this study (24.7 & 28.4%) and total carbohydrates (22.4 & 18.2%) were significantly reduced in tomato plants with 2000 eggs or 4000 eggs of M. incognita infection, respectively with the application of T. ornata (2.0%). These results support the findings of Clarke et al, (2014) in egg-plant and tomato that decrease may be due to some activities related to hypersensitive response. It is clear that plant growth depends on both cell division and cell expansion and that seaweed is involved in plant growth regulation through controlling the biosynthesis of hydroxyproline containing protein.…”

Rapid Methodologies for AssessingPseudomonas syringaepv.actinidiaeColonization and Effector-Mediated Hypersensitive Response in Kiwifruit

“…The biolistic approach also allows organelle targeting, does not require the discovery of a co-evolved Agrobacterium strain, and is often significantly more rapid in application than other transient expression methods (Lacroix and Citovsky, 2020). However, the biolistics approach has only moderate throughput as each sample requires significant handling, thus is not an ideal first tool for screening large numbers of plants (Table 1) but instead is useful as a heterologous system free of HR-like elicitation occasionally associated with recognition of the type III secretion system itself (Clarke et al, 2014(Clarke et al, , 2010. In contrast, the HR-associated electrolyte leakage assays are eminently suitable for high-throughput screens of multiple cultivars and F 1 /F 2 mapping populations from crosses.…”

A Comprehensive Review on Recent Advances in the Research on Bacterial Leaf Spot in Tomato Caused by Xanthomonas Species

“…Tomato cultivars that are resistant to tomato and pepper bacterial spot pathogen races have been identified (Bonshtien et al, 2005;. However, these cultivars have not been widely adopted , possibly because the resistance is not long lasting (Stall et al, 2009;Clarke et al, 2014), and the available resistant cultivars are not resistant to all strains of the pathogen.…”