Sugar beet cultivation is significantly impacted by Heterodera schachtii, requiring effective and sustainable management practices to ensure crop productivity and soil quality. The efficacy of nine compost and manure-based organic amendments was investigated for their potential to manage sugar beet cyst nematode (SBCN) populations and enhance sugar beet yield and quality. A multi-phase research approach was employed, which included laboratory egg-hatching assays, greenhouse trials, and microplot experiments conducted under semi-field conditions. In laboratory egg-hatching experiments, poultry and swine manure consistently demonstrated significantly lower hatching rates compared to water and other treatments, suggesting their potent inhibitory effects on nematode reproduction. The suppressive effects of organic amendments were confirmed in greenhouse trials, where poultry manure and Layer Manure® were shown to reduce cyst, egg, and juvenile populations at higher application rates. In microplot trials, these amendments maintained their effectiveness, achieving significant reductions in SBCN populations and enhancing sugar beet yield and Brix percentage, which indicated improved sugar content. Furthermore, organic amendments were found to stimulate beneficial soil nematode populations, with poultry manure increasing bacterivore and fungivore nematodes. The results underscored the potential of organic amendments, particularly poultry manure and Layer Manure®, as alternatives to chemical nematicides. These amendments were demonstrated to offer a multifaceted approach to nematode management while improving crop productivity and soil quality.
Keywords: Beet cyst nematode; Egg hatching assay; Organic amendments.