Bacillus altitudinis and Bacillus cereus boost wheat yield and soil fertility in calcareous soil

Bacillus altitudinis and Bacillus cereus Enhance Wheat Growth in Nutrient-Poor Calcareous Soils

A groundbreaking study published in Chemical and Biological Technologies in Agriculture (2025) has revealed that two bacterial species, Bacillus altitudinis and Bacillus cereus, can significantly enhance wheat growth, nutrient uptake, and soil health in calcareous soils—one of the most nutrient-deficient soil types worldwide.

Led by Muhammad Zahid Mumtaz and colleagues, the research explored how mineral-dissolving rhizobacteria could serve as eco-friendly “rhizonutrifying” agents, enhancing the soil’s biological and enzymatic functions without relying heavily on chemical fertilizers.

Study Overview

The team isolated and characterized rhizobacterial strains from the wheat rhizosphere and tested their ability to dissolve insoluble minerals, such as tricalcium phosphate, mica, zinc oxide, and manganese oxide. These bacteria were further examined for their enzymatic and plant growth-promoting activities under controlled pot experiments.

Among the isolates, the most effective strains were identified as Bacillus altitudinis (SAM1, SAM7, SAM13, SAM15) and Bacillus cereus (SAM9). Through the production of organic acids like gluconic, citric, and oxalic acids, these strains transformed otherwise inaccessible soil minerals into plant-available nutrients.

Key Findings

Enhanced Nutrient Solubilization: Both bacterial species increased the availability of phosphorus, potassium, zinc, and manganese by reducing soil pH through organic acid production.
Improved Plant Growth: Wheat plants treated with B. cereus SAM9 and co-inoculated with B. cereus SAM9 + B. altitudinis SAM13 showed the most significant increases in shoot and root biomass, grain yield, and nutrient accumulation.
Boosted Soil Enzymatic Activity: The inoculated soils exhibited higher microbial biomass carbon, nitrogen, and phosphorus, along with elevated enzymatic activity—indicating healthier soil metabolism.
Sustainable Fertilizer Alternative: The study highlights these bacterial strains as promising biofertilizer candidates for alkaline, nutrient-deficient soils, offering an environmentally safe supplement or substitute for chemical fertilizers.

Why It Matters

Calcareous soils—common across South Asia, the Middle East, and arid regions globally—often limit nutrient bioavailability, constraining agricultural productivity. By employing naturally occurring rhizobacteria, farmers could restore soil fertility, improve crop yields, and reduce dependence on synthetic inputs.

This research demonstrates that targeted microbial inoculants like Bacillus altitudinis and Bacillus cereus can help achieve sustainable agricultural production and long-term soil health, marking an important advancement toward greener farming practices.

Reference

Mumtaz, M. Z., Aslam, R., Li, L., Ghafoor, S., Khan, S., Fahim, A. M., Alsakkaf, W. A. A., & Ali, H. M. (2025). Bacillus altitudinis and Bacillus cereus strains improve soil fertility, nutrient acquisition, biomass production, and yield of wheat grown on calcareous soil. Chemical and Biological Technologies in Agriculture, 12(1), 146. https://doi.org/10.1186/s40538-025-00854-3