Biological protection conferred by Glomus spp. and Bacillus megaterium againstMeloidogyne incognita in tomato and pepper

Abstract: Pot experiments were carried out under controlled greenhouse conditions to determinethe effects of the combined use of AMFs (Glomus intraradices or Glomus mosseae) and a PGPR(Bacillus megaterium) on root-knot nematode (Meloidogyne incognita) reproduction and growthrates in commercial pepper and tomato cultivars. Nematode reproduction and plant growth werefound to vary greatly, depending on the plant species and cultivars concerned. However,nematode reproduction and disease severity (estimated by the gall index) were reduced and plantgrowth increased in all mycorrhizal plants. Reductions in plant growth caused by M. incognitawere compensated through root colonization by Glomus spp. Nematode infestation did not affectmycorrhizal colonization of roots. No synergistic effects from the combined use of AMFs withB. megaterium in tomato were observed but in pepper cv. Perico the decrease in nematodereproduction was more significant when G. mosseae and B. megaterium were used together thanwhen used separately. Reductions in root colonization by mycorrhizal fungi in commercialtomato varieties carrying resistance genes to Fusarium were only observed in one out of five ofthe tomato cultivars tested.