Development and effectivity of Solanum sisymbriifolium against potato cyst nematode under field conditions in soils from the southern atlantic area

Abstract

Potato cyst nematodes (PCNs), belonging to the genus Globodera spp., are spread worldwide constituting a problem of concern as they can cause considerable losses in crop yields. An alternative to the application of common pesticides is the use of trap crops, that promote the hatching of second-stage juvenile cysts without supporting the feeding and reproduction of these nematodes. For this purpose, in recent years, there has been growing attention to the use of Solanum sisymbriifolium as a biopesticide. In this study, we focused on looking for the best conditions to grow this trap crop under field conditions, contrary to previous studies developed in pots under controlled conditions. Various management strategies, including sowing date and depth, irrigation and soil compaction, to grow S. sisymbriifolium in acid sandy soils (pH 4.3–5.5) have been evaluated. In addition, the efficiency of S. sisymbriifolium was tested under field conditions in three PCN-infested plots. The results indicate that the best conditions for S. sisymbriifolium cropping in South Atlantic latitudes included sowing dates in July and August at 10–15 cm depth, with irrigation and soil compaction after sowing. Under these conditions, a 77%–89% decrease in PCNs was observed with a high initial number of cysts (93–160 per 100g), and even some sub-plots showed a 100% reduction when the initial number of cysts was low (15–52 per 100g). Therefore, S. sisymbriifolium could be an interesting substitute for unspecific chemical nematicides in potato crops to promote sustainable agriculture.