Effect of Laying Hen Manure on Soil Biological Activity, Mycorrhizal Symbiosis and Nutrition of Pearl Millet

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Résumé

Purpose: Agricultural intensification requires the careful selection of fertilizers. While laying hen manure (LHM) is widely recognized for improving pearl millet productivity, its effects on soil biological activity and mycorrhizal symbiosis are not well documented. This study aimed to assess the short-term effects of LHM on soil biological activity, mycorrhizal symbiosis, and mineral nutrition of pearl millet.
Method: The experiment was conducted under controlled conditions in a greenhouse at Joseph KI-ZERBO University in Burkina Faso using a Completely Randomized Design (CRD) comprising three treatments: control (0 g/pot), LHM (240 g/pot), and mineral fertilization (4.8 g NPK + 2.4 g urea/pot), with four replicates. At 45 days after sowing (flowering stage), soil biological activity was assessed. Concurrently, mycorrhizal symbiosis parameters and foliar macronutrient concentrations were determined.
Results: LHM-amended soils showed significant increases in microbial biomass (1212.53 ± 11.07 mg C/kg soil) and soil respiration (497.13 ± 4.54 mg CO₂/kg soil) compared with the control. Similarly, foliar concentrations of nitrogen (1.8 ± 0.03%), phosphorus (0.69 ± 0.01%), and potassium (2.79 ± 0.14%) were significantly enhanced under LHM application. The frequency of mycorrhizal colonization and vesicle occurrence remained unaffected by LHM.” In contrast, a reduction in arbuscule frequency (24.44 ± 1.92%), as well as in overall mycorrhizal intensity (18.34 ± 1.75%) and arbuscular intensity (1.28 ± 1.10%) within the root system, was observed in LHM-amended soils.
Conclusion: Under short-term controlled conditions, laying hen manure exhibited favorable fertilizing properties, stimulating soil biological activity and enhancing the mineral nutrition of pearl millet.

Mots-clés

Soil microbial biomass, Soil respiration, Mycorrhizal root colonization, Pearl millet nutrition, Organic manure amendment