Halotolerant bacteria isolated from extreme environments induce seed germination and growth of chia (Salvia hispanica L.) and quinoa (Chenopodium quinoa Willd.) under saline stress

YAÑEZ-YAZLLE, MARÍA FLORENCIA; ROMANO-ARMADA, NELI; ACRECHE, MARTÍN MOISES; RAJAL, VERÓNICA BEATRIZ; IRAZUSTA, VERÓNICA PATRICIA

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2021 vol. 218

0147-6513

The aim of the study was to characterize halotolerant bacteria and to evaluate their plant growth promotionpotential on chia and quinoa seedlings under saline stress. Isolated microorganisms were evaluated for nitrogenfixation, phosphate solubilization, and production of siderophores and indole acetic acid. Three strains and twoconsortia were selected: Halomonas sp. (SFS), Micrococcus luteus (SA211), Bacillus sp. (HX11), C1 (SA211 + SFS),and C2 (SA211 + HX11). In vitro assays using water agar and half-strength Murashige-Skoog plates showed thatan increase in salinity led to an increased seedlings mortality and a decrease in germination (lower than 40%), intotal length (varying between 16% and 87% decreases), root length (from 60% to 92% lesser length) and dryweight (from 7% to 86% lower weight). Also, the relative growth index (RGI) decreased for both crops in mosttreatments, except those with HX11 and C2. These treatments had the highest growth parameters and RGI valuesin presence of high salinity in chia (50 and 100 mmol/L NaCl) and quinoa (200 and 400 mmol/L NaCl). SA211,the highest producer of indole acetic acid, showed a detrimental effect and anomalous phenotype on plants. Ourresults suggest that Bacillus sp. HX11, with multiple plant growth promotion traits and tolerance to saline stress,has a great potential as a bioinoculant in saline conditions and could be used as a biofertilizer for cropproduction.