Identification of Resistance Sources to Root-Knot Nematode in Sugar Beet

Sugar beet (Beta vulgaris) is one of the hosts for root-knot nematodes. In this study, two open-pollinated populations and their half-sib families (37 families), two hybrids of sugar beet and the commercial resistant cultivars to cyst nematode (Heterodera schachtii), including Tucan, Cactus, Saneta, Pauletta, Paulina, Fernando, Sucarra and Shokufa, were evaluated against Meloidogyne javanica and M. arenaria in the separate experiments under greenhouse condition. Seedlings were inoculated with 500 and 750 second-stage juveniles. About 70 days after inoculation, the plants were taken off and the number of root-galls in roots was counted. Individual plants with 10 and less than 10 galls in root were considered as a resistant. Results indicated that SB33 and SB34 open-pollinated populations and total their half-sib families were resistant to root-knot nematode and the resistance in SB33 population is inherited in a dominant manner. Also the all resistant cultivars to cyst nematode, were susceptible to root-knot nematode.