Soil bacteria conferred a positive relationship and improved salt stress tolerance in transgenic pea (Pisum sativum L.) harboring Na+/H+ antiporter

Abstract

Among grain legumes, peas (Pisum sativum L.) are highly sensitive to salt stress. Acclimatization of plants to such conditions is mandatory. We provide improved salt stress tolerance response of transgenic pea plants overexpressing the Na + /H + gene from Arabidopsis thaliana and a positive association with salt-tolerant plant growth-promoting rhizobacteria (PGPR). In addition to salt stress tolerance and phosphate solubilization, the selected rhizobacterial isolates were identified for indole acetic acid and proline production ability. Seed germination percentage in transgenic pea plants was significantly higher under NaCl challenge. The wild-type (WT) pea plants inoculated with known numbers of viable cells of salt-tolerant PGPR and transgenic pea plants without any inoculation showed better growth performance under salt stress. However, the PGPR-inoculated transgenic plants showed significant increase in growth and biomass compared to the WT counterpart. An increase in antioxidant enzymes, i.e. superoxide dismutase and peroxidases, was observed in PGPR-inoculated transgenic plants under salt stress. We could not see any negative effect of the transgene in pea plants on the growth of associated PGPR. The overall impact of microbe-mediated elicitation responses in transgenic plants, whether at the biochemical or molecular level, may lead to protection against salt stress.

Salt-tolerant plant growth-promoting bacteria enhanced salinity tolerance of salt-tolerant alfalfa (Medicago sativa L.) cultivars at high salinity

“…It appeared that inoculation plant with bacteria could change lateral root system architecture and increase RWC. Similar results were reported in alfalfa (Bertrand et al 2015), Zea mays (Bano and Fatima 2009), and pea plants (Ali et al 2015). Na + ions could disturb MSI as soon as they enter the cells (Volkov 2015).…”

Rhizobacterial communities of five co-occurring desert halophytes

“…Shifts in bacterial community composition in bulk soils versus the rhizosphere may be the consequence of active selection by plants ( Kowalchuk et al, 2002 ). As many endophytes and bacteria colonizing root surfaces have beneficial effects, such as nitrogen fixation, phytohormone production, nutrient supply and pathogen suppression ( Rosenblueth & Martinez-Romero, 2006 ; Hardoim, van Overbeek & van Elsas, 2008 ), they typically promote plant growth and can alleviate salt stress in halophytes ( Ali et al, 2015 ). Some Microbulbifer and Planococcus species have the ability to degrade complex hydrocarbons ( See-Too et al, 2017 ).…”

Engineering salinity tolerance in plants: progress and prospects

“…However, it is important to note that the transformation of crop plants using a single gene approach might not provide total tolerance with high yield potential, as abiotic stress tolerance is often controlled by multiple genes (Abe et al 2012). While omics and transgenic approaches were demonstrated to mitigate the negative effects of salinity, introducing halotolerant bacterium into salt contaminated fields was proved to be beneficial for the growth of Pisum sativum (Ali et al 2015), Lycopersicon esculentum (Fan et al 2016), Arachis hypogaea (Sharma et al 2016), Chenopodium quinoa (Yang et al 2016) and Triticum aestivum (Raheem and Ali 2015). Therefore, exploring halobiomes to identify and isolate genes that confer salt-tolerance could be a promising approach to enable crop plants to be grown in saline soils, but also simpler (but maybe more expensive and laborious) agricultural methods like introduction of special soil bacteria and fungi may be also interesting (Aroca and Ruiz-Lozano 2012; Shrivastava and Kumar 2015).…”