Morphological and Host Range Variation in the Heterodera Trifolii Complex

Abstract

Five populations belonging to the polyploid parthenogenetic Heterodera trifolii complex were found to differ in host range. Statistically significant morphometric differences were found between some of the populations, tending to be more pronounced when each nematode was grown on its specific host plant. In order to provide a practical phytopathological classification of such populations the use of the term forma specialis is proposed. In this system H. galeopsidis Goffart, 1936 is synonymized with H. trifolii Goffart, 1932.