Multi-Marker Approach for the Identification of Different Heterodera Species (Nematoda: Heteroderidae)

Cyst nematodes of the genus Heterodera are important plant-parasitic nematodes that cause significant crop losses worldwide but are often overlooked due to their non-specific symptoms and complex biology. This study assessed Heterodera diversity in Portugal using an integrative molecular approach based on four genetic markers (mtCOI, 18S rDNA, ITS, and 28S rDNA). Five valid species were identified: Heterodera cruciferae, H. mani, H. schachtii, H. trifolii, and H. zeae, with H. mani reported for the first time in the country. A distinct taxon from Coimbra (central Portugal) may represent a new or unsequenced species, highlighting gaps in reference datasets. Among the markers, mtCOI was the most effective, though some taxa remained unresolved. These results reinforce the value of multi-marker approaches, contribute with new sequences, and improve diagnostic capability for nematode management.