Review Article | Vol. 9 Issue 4 (2026), e2026151 | Published in 09 September 2025

Applications of inoculants to treat drought stress in plants

• Domenico Prisa  
• Aftab Jamal 

Link: https://10.31893/multirev.2026151

• AbstractAll climatic factors, including temperature, rainfall, humidity, wind, and solar radiation, significantly influence agricultural activities. These environmental conditions determine the types of crops that can be grown, the length of growing seasons, and the overall productivity of agricultural systems. While some agricultural areas around the world rely on artificial irrigation, the vast majority still depend heavily on natural rainfall patterns. This reliance makes agriculture particularly vulnerable to climate variability and change. Climate change is expected to increase the frequency and severity of extreme weather events, such as droughts and heatwaves, which will lead to higher water demands from crops while simultaneously reducing water availability. This imbalance between water supply and demand is likely to result in reduced crop yields and lower production capacity in many regions. One of the most critical challenges faced by agriculture under climate change is drought. Drought stress severely limits plant growth and productivity by affecting physiological and biochemical processes. However, plant growth-promoting bacteria (PGPB) offer a promising solution to this issue. These beneficial microbes enhance plant tolerance to drought by regulating gene expression and modulating hormone activity in plants. They also influence the stress-induced enzymatic system, alter phytohormone levels, and contribute to the accumulation of protective metabolites. These mechanisms are expressed through phenotypic changes in plant architecture, growth rate, root-to-shoot ratio, hydraulic conductivity, and water conservation abilities. Additionally, PGPB support plant cell protection under stressful conditions. This review aims to highlight the role of plant growth-promoting bacteria in mitigating the adverse effects of climate-induced stress on crops. By exploring how these microorganisms interact with plants to enhance resilience, it provides insight into potential applications of microbial biotechnology in agroecosystems. Ultimately, the integration of such microbial strategies into farming practices can contribute to more sustainable and climate-resilient agriculture.

Keywords:
 sustainable agriculture
 biofertilizers
 PGPB
 endophytic bacteria
 abiotic stress
 inoculant

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