the combination of biochar and rhizobacteria improved leaf pigments and growth of oilseed rape under salinity

Objective: soil salinity is a major environmental constraint that significantly influences plant growth and productivity. application of carbon-rich materials and rhizobacteria may reduce the negative impacts of environmental stresses such as soil salinity on plants. thus, this research aimed to investigate the possible roles of solid and enriched biochars with pseudomonas putida rs-198 and azotobacter chroococcum rs-106 on the physiological performance and grain yield of oilseed rape under salinity.methods: a factorial experiment with randomized complete block design in three replicates was laid out in a greenhouse at the university of tabriz, iran, to find out the effects of solid biochar (30 g biochar per 1 kg soil) and enriched biochars with pseudomonas putida (100 ml bacteria in 1 kg-1 of biochar), azotobacter chroococcum (100 ml bacteria in 1 kg-1 of biochar), and p. putida + a. chroococcum (50 ml p. putida + 50 ml a. chroococcum in 1 kg-1 of biochar) on nutrient uptake, osmotic adjustment, photosynthetic activity, and yield components of oilseed rape plants under salt stress (0, 6, and 12 ds m-1 nacl; as non-saline, and moderate and high salinities, respectively).results: the na+ uptake and osmolytes were enhanced, but the k+ uptake, ca2+ and mg2+ contents, leaf water content, photosynthetic activity, plant growth, grain yield, and yield components were decreased with increasing salt stress. the biochar-related treatments reduced the negative impacts of salt stress by decreasing na+ uptake and increasing nutrients and water contents, soluble sugars, leaf pigments, plant biomass, seeds per plant, and grain yield, particularly under high salinity. in addition, the combination of biochar and p. putida + a. chroococcum was the superior treatment in enhancing pods per plant of oilseed rape.conclusion: the integrated application of biochar and rhizobacteria could be a new method worthy of consideration for improving plant growth and productivity in saline soils.