# The potential of Pseudomonas spp. as sustainable bioinoculants for enhancing maize growth and integrated management of drought and Fusarium verticillioides stress

## TL;DR

This paper reviews how Pseudomonas bacteria can help maize plants withstand drought and a fungal infection, offering a sustainable solution to boost crop yields and safety.

## Contribution

The paper introduces Pseudomonas spp. as a dual-purpose bioinoculant for mitigating both drought and Fusarium stress in maize.

## Key findings

- Pseudomonas spp. improve maize resilience by enhancing nutrient uptake and antioxidant defenses.
- These bacteria suppress Fusarium verticillioides through antifungal compounds and systemic resistance.
- Combined stress studies on Pseudomonas are limited, highlighting a need for further research.

## Abstract

The review highlights PGPR (e.g., Pseudomonas spp.) as sustainable, low-cost solution to mitigate drought and Fusarium stress in maize, enhancing yield and resilience.

Maize (Zea mays L.) is a vital staple crop worldwide, yet its productivity is under growing pressure from the combined effects of drought and Fusarium verticillioides infection. These stresses often occur together, compounding the damage. Drought limits water availability, disrupts nutrient uptake, and slows photosynthesis, while also making plants more vulnerable to disease. In turn, F. verticillioides harms plant tissues, contaminates grain with fumonisins, and can further intensify water stress. Conventional approaches such as irrigation, fungicides, and resistant cultivars often fall short when both stresses occur simultaneously. In recent years, plant growth-promoting rhizobacteria (PGPR), particularly Pseudomonas spp., have gained attention as eco-friendly partners in managing these challenges. These beneficial bacteria support maize growth by improving nutrient availability, regulating plant hormones, enhancing osmoprotectants’ production, activating antioxidant defenses, and suppressing pathogens through antifungal compounds, competitive root colonization, and induced systemic resistance. Findings from single-stress experiments show that Pseudomonas endophytes can boost drought tolerance by maintaining osmotic balance and antioxidant activity, while also limiting F. verticillioides infection and toxin production. However, studies examining their effectiveness under the combined pressures of drought and fungal attack remain limited. This review brings together current knowledge on the mechanisms, case studies, and practical constraints of Pseudomonas-mediated stress relief in maize, highlighting research gaps and setting priorities for strain selection, microbial consortia design, and large-scale field testing. Harnessing these bacteria could be a key step toward building climate-resilient maize production systems that protect both yields and grain safety in an era of environmental uncertainty.

Exogenous application of Pseudomonas spp. modulate drought and Fusarium verticillioides.