Reaction of sugarcane genotypes to root-knot nematodes (Meloidogyne spp.) in Kenya

Abstract

Resistance/tolerance to some parasitic nematodes has been found to exist in various sugarcane cultivars in varying degrees. This trait has not been fully exploited especially in Kenya. Fifteen sugarcane cultivars were randomly selected and grown under a glass house in a completely randomized design with three replications over two seasons. Single-budded setts were inoculated with 2000 J2 root-knot nematodes (Meloidogyne spp.). Infestation of root-knot nematodes (RKN) on Co 421 reduced fresh root weight by 33%, reduced tillering of Co421, KEN82-62 and KEN98-530 by 70%, 46% and 33% respectively, but did not affect those of KEN00-13 and KEN82-121. Uniquely, nematode inoculation promoted tillering of EAK 70-97 and N14 which increased by 21% and 30% respectively. Co421 and D8484 hosted the highest nematode population numbers with mean egg mass indices of 3.0 and 2.5 respectively. Conversely, KEN83-737 and Co945 had lowest nematode numbers with mean egg mass indices of 0.8. This study demonstrated that sugarcane cultivars do exhibit varying degrees of host resistance or tolerance to RKN. The resistant/ tolerant cultivars may be incorporated into integrated nematode management packages.