Harnessing beneficial microbes to counteract the negative impact of microplastics (raw and aged) on plant health and oxidative balance

• Aged MPs induce severe oxidative stress and growth inhibition vs. raw MPs in maize. • Combined microbial inoculation effectively mitigates MPs-induced stress in maize. • Microbial inoculation restores antioxidant defense and AsA-GSH cycle in MPs-stress. • Aged MPs disrupt proline/MAPK pathways; microbial treatments alleviate damage. • Microbial consortia emerge as sustainable solution for MPs-contaminated soils. Microplastics (MPs) contamination in agroecosystems is a major threat to soil, plant growth, and agricultural productivity. The toxicity of MPs is higher in aged-MPs than raw-MPs, owing to their prolonged environmental exposure and surface modifications. It is crucial to address the MPs-induce stress, to ensure sustainable agriculture; and to protect MPs entry into the food chain. In the current investigation, the impact of raw and aged MPs on maize ( Zea mays ) and efficacy of sole and combined ecofriendly microbial inoculation ( Trichoderma longibrachiatum (TD) and Bacillus subtilis (BS) in mitigating MPs-induced stress. We observed that, relative to the raw-MPs, aged-MPs induced stress exerted more detrimental impact on plant growth, biomass, oxidative stress biomarkers, antioxidant defence system, Ascorbate-glutathione cycle and glyoxalase system. In contrast, microbial inoculation significantly enhanced plant immunity by effectively reducing the oxidative stress induced by MPs (both raw and aged MPs), through increased antioxidant enzyme activities, up-regulated stress-responsive genes, restoration of Ascorbate-glutathione cycle and glyoxalase system, ultimately improving plant growth and biomass. Furthermore, PCA plot demonstrated clear separation between treatments and indicated different physiological and biochemical responses of maize plants to MPs and microbial inoculation. Moreover, heatmaps and correlation analyses showed that aged-MPs enhanced oxidative stress, microbial inoculation modulated stress markers and enhanced antioxidant defense systems in a treatment specific manner. However, further exploration is required to explore applications of microbial consortia at field trials and their integration into sustainable agricultural practices to address MPs contamination.