Strains 42P4 and 60I1 alleviate NaCl stress in pepper plants

MIGUEL ANDRES LOBATO; MARÍA MICAELA PÉREZ RODRIGUEZ; ROMINA PAULA MONASTERIO; ANA CARMEN COHEN

Santa Fe

Congreso; XXXIII Argentinian meeting of Plant Physiology; 2021

Reunión Argentina de Fisiología Vegetal

Environmental stress plays an important role in crop yields of pepper grown in Argentina. Soil salinity is an important agricultural problem, particularly since the majority of crop plants have low salt tolerance. Salt stress limits growth and yield of pepper grown in Mendoza province. There are numerous reports on the beneficial effects of rhizosphere microorganisms on plant growth, an important group of beneficial soil microorganisms are the PGPR (plant growth-promoting rhizobacteria). Under saline stress that one way that PGPR stimulate plant growth is through the activity of the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which causes a lowering of plant ethylene levels resulting in longer roots. In general, PGPR can improve plant development by producing hormones or plant growth regulators and improving the availability of nutrients such as Nitrogen, phosphorus and potassium. The objective of this study was to evaluate the effect of the inoculation of pepper plants under saline stress with two native strains of Mendoza. The test was carried out under greenhouse conditions. A randomized design of 5 treatments was established, with three repetitions of 10 plants each. The treatments were the following: 1) Control, 2) 42P4 + NaCl, 3) 60I1 + NaCl and 4) NaCl. Plants under saline stress were watered with a 150 mM NaCl solution. During the development of the experiment morphological, physiological and biochemical variables were evaluated. The results showed that the 42P4 and 60I1 strains alleviate saline stress by increasing plant height, stem diameter, photosynthetic efficiency, chlorophyll index (SPAD), aerial and root dry weight, and photosynthetic pigment content.