Salicylic and jasmonic acid-mediated defence genes regulation in leaves of flooded tomato plants

BARONE, JAVIER ORLANDO; MIGNOLLI, FRANCESCO; MARIOTTI, LORENZO; VIDOZ, MARÍA LAURA

Congreso; XXXIII Argentinian Meeting of Plant Physiology; 2021

Given the increase in flooding events and the fact that multiple stresses generally occur simultaneously, it is crucial to understand how partially submerged plants respond to biotic stresses. Flooding causes changes in hormonal interaction during adaptive responses. The objective of this study was to assess flooded tomato plant responses to biotic stress. For this, 30 days old tomato plants were subjected to flooding for 6 days and the concentration of salicylic (SA) and jasmonic acid (JA) was determined in leaves. In addition, the expression of SA responsive genes induced by pathogens such as NONEXPRESSOR OF PATHOGENESIS-RELATED GENES 1 (NPR1), PATHOGENESIS-RELATED GENES (PR1a and PR2a), and the expression of JA responsive genes, induced by herbivores, such as PROTEINASE INHIBITOR (PI-I and PI-II) was analysed. The expression of the ALLENE OXIDE SYNTHASE (AOS) gene, involved in JA biosynthesis, was also measured. Flooding increased SA concentration along with the upregulation of NPR1, PR1a and PR2a whereas a decrease in JA content was observed. Consistently, PI-I and AOS expression levels were reduced while the expression of PI-II did not change in leaves of flooded plants. These data suggest that flooding may prepare plants to pathogen resistance at the expense of increased susceptibility to herbivores.