Effects of Solanum sisymbriifolium on potato cyst nematode populations in Portugal

This study was undertaken to evaluate the effects of Solanum sisymbriifolium cvs Melody, Pion, Sharp, Sis 4004 and Sis 6001 on potato cyst nematode (PCN), Globodera spp., populations in the field in Portugal, to improve crop protection systems based on trap crops. Two PCN infested fields (Bolho and Barcou double dagger o) were selected. Solanum sisymbriifolium root exudates effects on PCN hatching were evaluated by in vitro assays and their susceptibility/resistance to PCN was assessed. Field trials were performed during 2 years using the following rotation: S. tuberosum cv. D,sir,e followed by S. sisymbriifolium. Solanum sisymbriifolium root exudates promoted hatching of second-stage juveniles (J2). The cultivars tested were resistant to both species of PCN. In both fields, all cultivars had the same behaviour with no statistically significant differences. As S. sisymbriifolium cultivars were resistant to G. rostochiensis and G. pallida populations in Portugal, they can be included in crop rotations and are potential candidates to incorporate in management programs against PCN. Although there were no statistical differences it seems that fallow could be the best strategy to reduce PCN populations faster and this avoids the introduction of an exotic plant that could become a problem.