Enhancing salt tolerance in quinoa by halotolerant bacterial inoculation

Abstract

Quinoa is a facultative halophytic seed crop of increasing interest worldwide. Its performance declines under high salinity but can be improved by using halotolerant plant growth-promoting bacteria (PGPB) containing multi-traits, i.e. ACC-deaminase activity, exopolysaccharide secretion and auxin production. This study focussed on improving the productivity of quinoa through the use of six plant growth-promoting bacterial strains (both endophytic and rhizosphere). These were screened by conducting osmoadaptation assay, and the two most halotolerant strains (Enterobacter sp. (MN17) and Bacillus sp. (MN54)) were selected. These two strains were evaluated for their effects on growth, physiological characters and yield of quinoa. At the five leaf stage plants were irrigated with saline water having either 0 or 400 mM NaCl. The results indicated that saline irrigation significantly decreased the growth of quinoa, whereas inoculation of plants with MN17 and MN54 mitigated the negative effects of salinity by improving plant water relations and decreasing Na+ uptake, which consequently, reduced osmotic and ionic stress. Strain MN54 performed better than MN17, which might be because of its better growth promoting traits and higher rhizosphere colonisation efficiency than MN17. Our results suggest that growth and productivity of quinoa could be improved by inoculating with highly tolerant PGPB strain in salt-affected soils.

Saponin seed priming improves salt tolerance in quinoa

“…Growth and yield decreased significantly under saline irrigation in the present study (Figure ), also demonstrated previously by Yang et al. (). However, priming with saponin leads to positive effects both under saline irrigation and non‐saline irrigation, most pronounced after the application of 15% and 25% saponin.…”

“…Leaf CCI content was increased under salinity condition (Figure ), which might be due to enhanced nitrogen‐containing compounds, and similar findings were reported in our previous study on quinoa (Yang et al., ). However, only application of saponins at 15% as a priming agent could significantly enhance A n and g s under salinity.…”

Soil drenching of paclobutrazol: An efficient way to improve quinoa performance under salinity

“…The salinity‐induced ionic imbalance and oxidative damages resulted in a decline of photosynthesis, which eventually lead to significant reduction in plant height, panicle length and grain yield of quinoa (Yang et al , Iqbal et al , Yang et al ). PBZ application improved grain yield and its contributing attributes under saline conditions (Table ), which can be attributed to an appropriate functioning of the plant's photosystems under salinity.…”

“…Quinoa also provides a highly nutritious food source that can be cultivated on marginal environments, which is not currently feasible for other major crops. Quinoa can achieve optimal growth and biomass between 100 and 200 mM (10, 20 dS m −1 ) of salinity (Jacobsen et al , Hariadi et al , Iqbal et al ), and 400 mM salinity causes significant reduction in growth and yield (Hariadi et al , Yang et al , Waqas et al , Yang et al ). However, the salt tolerance potential of quinoa greatly differs among genotypes (Schmockel et al ).…”

Consortium Application of Endophytic Bacteria and Fungi Improves Grain Yield and Physiological Attributes in Advanced Lines of Bread Wheat

“…MN54 was previously evaluated for enhancing growth and physiological attributes of Quinoa under normal and salt-stressed conditions (Yang et al 2016). The inoculum of selected bacterial strain MN54 was prepared using 10% Tryptic Soy Broth in 1000 mL Erlenmeyer flask incubated in a shaking incubator (Firstek Scientific, Tokyo, Japan) at 100 r.min -1 for 72 h at 28±1°C.…”