Antagonistic Interaction between Soil-Borne Root Rot Fungi and Potato Nematode Globodera Rostochiensis on Tomato Plants

Plant Protection Institute, BG-2230 Kostinbrod, Bulgaria


TRIFONOVA, Z., T. VATCHEV and S. MANEVA, 2003. Antagonistic interaction between soil-borne root rot fungi and potato nematode Globodera rostochiensis on tomato plants. Bulg. J. Agric. Sci., 9: 313–320

Interaction between potato cyst nematode Globodera rostochiensis pathotype – Ro1 and two root-rot fungi Fusarium oxysporum f. sp. radicis-lycopersici (FORL) and Colletotrichum coccodes were studied on tomato plants. In pot experiments test tomato plants were inoculated with each pathogen alone or in combinations of two and three pathogens either simultaneously or subsequently (at 10-day interval between first and second inoculation).
Maximum disease severity was exhibited in plants inoculated with G. rostochiensis followed by each fungal pathogen individually or both together. Both fungi caused a significant inhibitory effect on multiplication of G. rostochiensis, recorded as a lower population density of the nematode at the end of the experiment. Soil-borne pathogenic fungi Fusarium oxysporum f. sp. radicis-lycopersici and Colletotrichum coccodes added alone or in combinations were found to cause grater reduction in root length and biomass that Globodera rostochiensis alone. Tendency of relationship between the disease severity and the root growth was not found in all combinations of fungal and fungal-nematode complexes.

Key words: plant pathogens, cyst nematodes, soil-borne fungi, complex etiology, multiply rate, disease suppression, and biological control