Evaluation of Phytotoxicity of Manure-Derived Fertilisers Using Seed Germination and Root Elongation Bioassays

Poultry manure is a valuable nutrient source, but insufficient stabilisation may cause phytotoxic effects during early plant development. This study evaluated the phytotoxicity of fresh and composted poultry manure using seed germination and root elongation bioassays. Elutriates of aerated and static compost mixtures, poultry manure composts, and fresh manure were tested on sunflower (Helianthus annuus L.), mungbean (Vigna radiata L.), and white mustard (Sinapis alba L.). Germination and relative root growth indices were calculated. Aerated compost mixtures showed minimal phytotoxicity, whereas fresh and partially composted manure strongly inhibited seedling development. Mungbean was the most sensitive species. Root elongation was more sensitive than germination, confirming bioassays as reliable tools for assessing compost maturity and fertiliser safety.