The current restrictions of the use of chemical nematicides have contributed to increase root-knot nematode (RKN) problems in horticultural crops and to make plant resistance (R) the most effective and sustainable method to control these pests. In tomato and pepper, several majorR-genes (Mi-1,Me1, Me3) have been identified and molecular markers useful for marker assisted selection have been developed. However, the possible occurrence of virulent nematode populations able to reproduce onR-plants may constitute a severe threat to this control strategy. Nevertheless, we observed a low reproduction rate on susceptible plants for populations selected onR-tomatoes or peppers, showing that selection for virulence results in fitness costs for the nematodes. Cross experiments also showed that both selected and wild RKN populations virulent onR-tomato are unable to reproduce onR-peppers and populations virulent onR-peppers are unable to reproduce onR-tomato. Moreover, in pepper,Me3-virulent populations could not overcomeMe1,thus considered as a robust and durableR-gene. This virulence strict specificity allows to recycle brokenR-genesin rotations. All these results have important consequences for the management ofR-plants in the field.
* e.g. tomato, pepper, etc
- Djian-Caporalino C. (2012). Root-knot nematodes (Meloidogynespp.), a growing problem in French vegetable crops.EPPO Bulletin(Bulletin OEPP- Revue des aspects réglementaires de la protection des végétaux - Organisation Européenne et Méditerranéenne pourla Protectiondes Plantes) 42 (1) : 127-137.
- Fazari A., Palloix A., Wang L.H., Hua M.Y., Sage-Palloix A.M., Zhang B.X., Djian-Caporalino C. (2012) The root-knot nematode resistance N-gene co-localizes in the Me-genes cluster on the pepper (Capsicum annuumL.) P9 chromosome. Plant Breeding131: 665-673.
- Castagnone-Sereno P., Djian-Caporalino C. (2011). Lutte contre les nématodes à galles en cultures maraîchères : des recherches pour promouvoir la durabilité des résistances variétales.Innovations Agronomiques15 : 55-64.
- Djian-Caporalino, C., et al. (2011). The reproductive potential of the root-knot nematodeMeloidogyne incognitais affected by selection for virulence against major resistance genes from tomato and pepper.European Journal of Plant Pathology131 (3) : 431-440.