Article ID: SZD-010
Soilborne pest and disease management is one of the most important challenges in the cultivation of sweet bell pepper, sweet pepper, and chili pepper (Capsicum annuum L.). In Japan, the nematode Meloidogyne incognita is a soilborne pest responsible for considerable economic losses. Unfortunately, although F1 rootstock cultivars resistant to M. incognita infestation have been developed, resistance-breaking populations of M. incognita have emerged that can attack these cultivars. To address this issue through crossbreeding, breeding materials that are resistant to the new populations of resistance-breaking nematodes are needed. Here, we obtained 288 Capsicum germplasms from the NARO Genebank (Japan) and screened them for resistance to infestation by normal nematodes (strain Mi-Nishigoshi), resistance-breaking nematodes (‘LS 2341’-derived strain), and nematodes collected from 14 sweet pepper fields in Miyazaki Prefecture, Japan. Two of the germplasms, ‘NuMex Bailey Piquin’ and ‘PM 217-1-3’, showed strong resistance to all of the M. incognita tested and were used for progeny testing. ‘NuMex Bailey Piquin’ was selected as the parental line for a new F1 rootstock with resistance to a wide range of nematodes, including resistance-breaking nematodes. Since segregation of resistance was observed in ‘NuMex Bailey Piquin’, we selected one line named ‘J159’ among the selfing population of ‘NuMex Bailey Piquin’ to fix the resistance to the resistance-breaking nematode. We then evaluated the nematode resistance of ‘J159’ F1s crossed with the doubled haploid line ‘KLDH89’, which is resistant to bacterial blight, normal nematodes, and pepper mild mottle virus (pathotype P1,2), but not to resistance-breaking nematodes. The ‘KLDH89 × J159’ cross not only showed high resistance to resistance-breaking nematodes, but also high yield when used as a rootstock. It is registered in Japan under the rootstock cultivar name ‘Dai-Hinata’.
