Halotolerant PGPR Pseudomonas 42P4 alleviates the negative effects of salt stress on tomato plants

PÉREZ-RODRIGUEZ, M.M.; LOBATO-URECHE M.; DÍAZ, A.; BARATTI, G.; PICCOLI, P.; PONTIN M.; COHEN, A.C.

Evento virtual

Congreso; XXXIII Argentinian meeting of Plant Physiology (RAFV2021); 2021

Sociedad Argentina de Fisiología Vegetal

Salinity is one of the principal abiotic stresses that limits the growth and productivity of crops. Tomato is the second most cultivable vegetable crop in the world and Mendoza is one of the principal industrial tomato producing areas in Argentina. Tomato is classified as a salinity sensitive plant. The use of plant growth promoting rhizobacteria (PGPR) is an interesting alternative to increase production and mitigate salinity stress. Therefore, the aim of the work was to evaluate the effect of Pseudomonas 42P4 inoculation in salt-stressed and non-stressed tomato plants. A greenhouse experiment was conducted. Tomato seedlings were inoculated with: 1) Pseudomonas 42P4 and 2) control (without bacteria). The salinity treatment was applied thirty-five days after sown: 1) 150 mM NaCl solution or 2) water. Physiological parameters were evaluated one month after the imposition of salt stress. Inoculation increased root dry weight, shoot dry weight and stem diameter of salt-stressed and non-stressed plants. Relative water content values decreased from non-stressed plants to salt-stressed plants. The malondialdehyde content increased in salt-stressed control plants; however it was reduced with 42P4 inoculation. The maximum efficiency of photosystem II (Fv / Fm) was lower in the control plants under saline stress compared to the inoculated plants. Total phenolic compounds were similar between treatments in non-stress conditions; however, they were increased in stress conditions by PGPR inoculation. The results of the work suggest that Pseudomonas 42P4 is a PGPR that can alleviate the negative effects of salinity stress on tomato plants.