Heinz-resistant tomato cultivars exhibit a lignin-based resistance to field dodder (Cuscuta campestris) parasitism

• DOI: 10.1093/plphys/kiac024
• Publication Date: 2022-01-26T12:14:19Z
• Authors: Min-Yao Jhu; Moran Farhi; Li Wang; Richard N Philbrook; Michael S Belcher; Hokuto Nakayama; Kristina S Zumstein; Sarah D Rowland; Mily Ron; Patrick M Shih; Neelima R Sinha
• Keywords: Cuscuta; Parasitic plant; Haustorium

Cuscuta species (dodders) are agriculturally destructive, parasitic angiosperms. These plants use haustoria as physiological bridges to extract nutrients and water from hosts. campestris has a broad host range wide geographical distribution. While some wild tomato relatives resistant, cultivated tomatoes generally susceptible C. infestations. However, specific Heinz (Solanum lycopersicum) hybrid cultivars exhibit resistance dodders in the field, but their defense mechanism was previously unknown. Here, we discovered that stem cortex these resistant lines responds with local lignification upon attachment, preventing parasite entry into host. Lignin Induction Factor 1 (LIF1, an AP2-like transcription factor), SlMYB55, R-gene for Lignin-based Resistance 1, CC-NBS-LRR (CuRLR1) identified factors confer by regulating lignification. SlWRKY16 is upregulated infestation potentially negatively regulates LIF1 function. Intriguingly, CuRLR1 may play role signaling or function intracellular receptor receiving signals effectors, thereby lignification-based resistance. In summary, four regulators control lignin-based response cultivars, parasitizing tomatoes. This discovery provides foundation investigating multilayer against potential application other essential crops attacked plants.