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Plant Science Today (PST)

Review Articles

Vol. 13 No. sp5 (2026): Recent Advances in Agriculture

Plant-associated microbiomes in castor cultivation: implications for climate resilience, nutrient management and soil restoration

DOI
https://doi.org/10.14719/pst.13585
Submitted
8 January 2026
Published
01-07-2026

Abstract

In arid and semi-arid zones, castor (Ricinus communis L.) serves as an essential bioenergy crop, yet its yields suffer from erratic weather patterns, diminishing soil quality and heavy dependence on synthetic inputs. Leveraging plant-beneficial microbiomes presents a promising, eco-friendly solution to elevate crop vitality and environmental adaptability. Endophytes such as Bacillus, Pseudomonas and Azotobacter promote vigour through nitrogen fixation, phosphorus mobilisation and hormone modulation. Meanwhile, rhizosphere communities especially arbuscular mycorrhizal fungi improve mineral absorption, hydration efficiency and resilience to water scarcity. Field trials reveal that tailored microbial inoculants slash chemical fertiliser needs by 30-40 %, stabilise production amid stresses, refine root systems, trigger immune pathways and enrich soil aggregation plus carbon stores. Challenges remain, including inconsistent outcomes from site-specific factors. This review consolidates current knowledge on microbiome composition, bioactive processes and practical benefits for castor agronomy, outlining strategies to embed these bio stimulants within resilient, low-input cultivation frameworks.

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