Use of N-gene and Me-gene peppers as rootstocks to reduce the impact of the Southern Root-Knot Nematode, Meloidogyne incognita, on a highly susceptible bell pepper cultivar

Abstract

Bell peppers are an excellent host for several root-knot nematode species, particularly the Southern Root-Knot Nematode (SRKN; Meloidogyne incognita) and can sustain serious damage because of these nematodes. One strategy to avoid nematode build-up and crop damage is the use of nematode resistant cultivars or plants grafted onto nematode resistant rootstocks. The objective of this study was to evaluate the effect of several M. incognita-resistant pepper cultivars and rootstocks on nematode multiplication, degree of pepper root-symptoms and yield. Nematode-susceptible pepper plants grafted onto resistant rootstocks were compared to susceptible non-grafted and own-root-grafted plants in greenhouse pot trials and field experiments. Plant growth or fruit yields were not different between the different rootstock treatments. Nematode-induced root symptoms (i.e., root-galling) and nematode reproduction, however, were strongly affected by the rootstock. Compared to plants growing on susceptible roots, root-galling and nematode reproduction were significantly reduced on the resistant rootstocks. There were no significant differences among the resistant rootstocks. Grafting susceptible bell pepper onto resistant rootstocks appears an effective strategy to manage root-knot nematodes. Increasing costs and regulation of nematicides used in soil fumigation, demand for organic produce, and developments in grafting technology resulting in lower transplant costs, likely will result in an increase in the use of grafted vegetables as an economically viable option in the future.