P-032 - Engineering disease-resistant tomatoes via SlMKP1A and SlMKP1B knockouts

Thursday, July 17, 2025

13:30 - 15:15

Location: Confex Hall 3

Crop resistance genetics and genomics

Author(s)

DB

Diego José Berlanga

Centro de Biotecnología y Genómica de Plantas (CBGP), Centro Severo Ochoa, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC)
Madrid, Madrid, Spain
AM

Antonio Molina

Full Professor
Centro de Biotecnología y Genómica de Plantas (CBGP), Centro Severo Ochoa, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC)
Madrid, Madrid, Spain
AM

Alberto Macho

Principal Investigator
Shanghai Center for Plant Stress Biology, Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences (CAS)
Shanghai, Shanghai, China (People's Republic)

Presenting Author(s)

MT

Miguel Ángel Torres

Associate Professor
Centro de Biotecnología y Genómica de Plantas (CBGP), Centro Severo Ochoa, Universidad Politécnica de Madrid (UPM) – Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA/CSIC)
Madrid, Madrid, Spain

MITOGEN-ACTIVATED PROTEIN KINASE PHOSPHATASE 1 (MKP1) negatively regulates reactive oxygen species (ROS) production and plant immunity. Accordingly, Arabidopsis mkp1 mutants display elevated ROS upon Microbe-Associated Molecular Pattern treatment and increased resistance to pathogens with different lifestyles. Here, we examined MKP1 function in tomato to explore its potential for breeding disease-resistant cultivars. Using CRISPR/Cas9, we generated knockout lines targeting the MKP1 orthologs SlMKP1A (Solyc05g054700) and SlMKP1B (Solyc05g013750). Slmkp1A and Slmkp1B tomato plants displayed a mild growth reduction during early development, but this effect was compensated at later stages. Additionally, they produced a greater number of smaller fruits, leading to an overall increased yield compared to the wild-type control (Moneymaker). Knockouts of each SlMKP1 gene significantly showed enhanced resistance to the hemibiotrophic bacterium Pseudomonas syringae pv. tomato DC3000 (bacterial speck) and to Ralstonia solanacearum GMI1000 (bacterial vascular wilt). Our analyses suggest that Slmkp1A and Slmkp1B mutant plants exhibit an early immune response, preventing pathogen progression at initial stages of colonization, indicating that SlMKP1A and SlMKP1B act as negative regulators of disease resistance in tomato, as described in Arabidopsis thaliana. These findings provide new strategies for breeding crops with both high resistance and high yield by inactivating MKP1 genes.