Field trial of trap cropping against the sugar beet cyst nematode Heterodera schachtii (Rhabditida: Heteroderidae) in Japan

Sugar beet cyst nematode (SBCN) is a serious pest of beet and Brassicaceae crops and was first detected in Japan in 2017. Two varieties of SBCN-resistant radish (‘Kobuberi-daikon’ and ‘KGM1804’) were selected for trap cropping based on pot experiments. However, their effect on the SBCN population was not confirmed under field conditions. In this study, field experiments were conducted to investigate the efficacy of these radishes on the SBCN population along with chemical treatment (1,3-dichloropropene and dazomet) and fallowing. Trap cropping using ‘Kobuberi-daikon’ and ‘KGM1804’ reduced the population density of SBCN to the same level (55–60% reduction in unhatched eggs) and was superior to fallowing, whereas the anti-nematode effect of both nematicides were higher than that of trap cropping (1,3-dichloropropene: 82% and dazomet: 66%). Considering the other advantages of trap cropping such as lower cost, environmentally friendliness and mitigating soil erosion, trap cropping using radish varieties tested in this study is a useful option for nematode management.