Host status of Rubus species and hybrids for the root lesion nematode, Pratylenchus penetrans

Abstract

The root lesion nematode, Pratylenchus penetrans, is a production-limiting pest in red raspberry, Rubus idaeus. Genetic resistance, as a tool to manage P. penetrans in raspberries, would reduce the impact of this nematode on raspberry productivity as well as reduce the need for pre-and/or post-plant chemical treatments to keep populations in control. The host status of 11 Rubus species (R. coreanus, R. crataegifolius, R. innominatus, R. leucodermis, R. niveus, R. parviflorus, R. parvifolius, R. pungens, R. spectabilis, R. sumatranus, and R. odoratus) for P. penetrans was evaluated in greenhouse studies. Additionally, hybrids of R. cockburnianus, R. lasiostylus, R. niveus, R. phoenicolasis, and R. sumatranus with R. idaeus ‘Meeker’ or ‘Tulameen’ were evaluated. The industry standard R. idaeus ‘Meeker’ was included in all trials as the control. Across trials, R. niveus and R. leucodermis were identified as poor hosts for P. penetrans. In addition, when another selection of R. niveus was evaluated in the final year of this study, it was also a poor host for P. penetrans. Among the remaining Rubus species materials tested, there were no consistent differences in host status for P. penetrans. It appears that R. niveus and R. leucodermis might be sources of resistance for P. penetrans. However, a hybrid between R. niveus and R. idaeus ‘Tulameen’ did not consistently support fewer P. penetrans than the ‘Meeker’ control. These results indicate that more research is needed to learn about the inheritance of the putative resistance.