Inocula and Media Affect Root-Knot Nematode Infection of Peach Seedling Roots

Abstract

Six initial population densities (Pi) (0, 2000, 4000, 6000, 8000 and 10,000 eggs per 1200 cm ³soil) of two root-knot nematode species [ Meloidogyne incognita(Kofoid & White) (Mi) and M. javanica(Treub) (Mj)] and four potting media (sand, sand/vermiculite, vermiculite, and Fafard) were used to evaluate nematode parasitism of ramets of seedlings of ‘Lovell’ peach [ Prunus persica(L.) Batsch] rootstock under greenhouse conditions. There were no significant differences in plant height, shoot dry weight, and root dry weight among different Pi treatments and different medium treatments for either nematode species, except that the ramets grown in Fafard medium had greater (P ≤ 0.05) plant height, shoot dry weight, and root dry weight. Our results indicated that a Pi of 4000 Mi or Mj eggs per 1200 cm ³soil was needed to produce reliable nematode infections on peach roots for the evaluation of host susceptibility, and sand/vermiculite was a suitable medium for root-knot nematode infection and reproduction on susceptible peach roots under greenhouse conditions.