Unlocking the potential of co-applied biochar and plant growth-promoting rhizobacteria (PGPR) for sustainable agriculture under stress conditions

Abstract

Sustainable food security is a major challenge in today’s world, particularly in developing countries. Among many factors, environmental stressors, i.e., drought, salinity and heavy metals are major impediments in achieving sustainable food security. This calls for finding environment-friendly and cheap solutions to address these stressors. Plant growth-promoting rhizobacteria (PGPR) have long been established as an environment-friendly means to enhance agricultural productivity in normal and stressed soils and are being applied at field scale. Similarly, pyrolyzing agro-wastes into biochar with the aim to amend soils is being proposed as a cheap additive for enhancement of soil quality and crop productivity. Many pot and some field-scale experiments have confirmed the potential of biochar for sustainable increase in agricultural productivity. Recently, many studies have combined the PGPR and biochar for improving soil quality and agricultural productivity, under normal and stressed conditions, with the assumption that both of these additives complement each other. Most of these studies have reported a significant increase in agricultural productivity in co-applied treatments than sole application of PGPR or biochar. This review presents synthesis of these studies in addition to providing insights into the mechanistic basis of the interaction of the PGPR and biochar. Moreover, this review highlights the future perspectives of the research in order to realize the potential of co-application of the PGPR and biochar at field scale. Graphical Abstract

Biochar-Soil-Plant interactions: A cross talk for sustainable agriculture under changing climate

“…The biochar also increased leaf area with a rise of 26% and 36% compared with the values measured in the untreated plants. Moreover, the amendment increased twofold root length, root surface area, and root, stem, and leaf biomasses in comparison with untreated plants (Simiele et al, 2022), could have a promoting effect on plant growth as an indirect consequence of its positive effect on growth medium parameters such as water holding capacity and pH enhancement, increased nutrient availability (Malik et al, 2022). Xi et al (2020) reported that the 2% (w/w) rice biochar application increased soil available N and K, resulting in taller lettuce plants, with longer roots, stronger leaves and stems, as well as greater leaf area.…”

Combined Application of Biochar and Plant Growth-Promoting Rhizobacteria Improves Heavy Metal and Drought Stress Tolerance in Zea mays

“…The maximum plant beneficial effect observed in ARN7 + GS-BC treatment can be attributed to the synergistic effects of biochar and PGPR. In general, biochar provides a stable environment for microbial growth and survival, thereby improving their colonization and subsequent PGP activity [ 29 , 30 ].…”

Biochar and Farm Yard Manure Synergy: Enhancing Soil Health and Mitigating Climate Change Impacts in Cotton Production

“…By creating a favorable environment for these microorganisms, biochar indirectly supports the crop's ability to withstand stressors associated with climate change, such as pests and diseases (Bibi and Rahman 2023). Numerous studies have consistently demonstrated the bene cial impact of soil amendments, such as biochar, on promoting crop growth and enhancing crop yields through the improvement of soil and water conditions (Ullah et al 2021;Malik et al 2022;Tyagi et al 2023). These amendments work by increasing the availability of essential nutrients, enriching organic matter content, and enhancing overall soil quality (Hussain et al 2019;Ye et al 2020).…”

“…The combined application of biochar and FYM in agricultural practices has emerged as a promising strategy that offers synergistic bene ts surpassing the outcomes of sole applications of either biochar or FYM (Nigussie et al 2021;Seleiman et al 2021). While biochar enhances soil structure, nutrient retention, and microbial activity due to its porous nature and high carbon content (Ullah et al 2021;Malik et al 2022;Tyagi et al 2023), FYM contributes to organic matter enrichment, nutrient supplementation, and microbial diversity (Chandra et al 2022;Ahlawat et al 2023). When these two amendments are applied together, their complementary effects create a holistic impact on the soil-plant system.…”