Integrated management of Meloidogyne incognita infecting tomato using bio-agents mixed with either oxamyl or organic amendments
AbstractThe effects of three commercial bio-products containing the bio-agents Bacillus megaterium (Bioarc®), Trichoderma album (Biozeid®) or Ascophyllum nodosum (Algaefol®), dried seed powder of Matricaria chamomilla and chitosan, each at 5 g or ml/kg soil, and the nematicide oxamyl at 0.01 g a.i/kg soil, alone or in combination, on Meloidogyne incognita in tomato were assessed in a glasshouse pot experiment. All treatments significantly improved plant growth and suppressed the nematode compared to untreated inoculated plants. Among the single treatments, the bio-products were the most effective with root gall reductions of 94.6% (Biozeid®), 89.1% (Bioarc®) and 81.7% (Algaefol®), similar to those obtained with the nematicide oxamyl (88.3%). The corresponding values for the suppression of the second-stage juveniles (J2) were 92.4%, 92.4% and 96.0%, again similar to oxamyl (91.2%). Chitosan and M. chamomilla were the least effective in suppressing the nematode. The efficacy of each of the bio-products against M. incognita was increased by the addition of oxamyl to the soil. The best combinations to reduce root galling (95.5%) and J2 in the soil (97.5%) were Biozeid® + oxamyl and Bioarc® + oxamyl, respectively. The combination of Algaefol ® + oxamyl significantly reduced tomato galling (88.4%) and M. incognita J2 in the soil (95.8%). The addition of the organic amendments chitosan and M. chamomilla to each of the bio-products increased the control of the nematode except for Biozeid® + M. chamomilla, Biozeid® + chitosan and Algaefol® + chitosan, which exhibited antagonistic interaction effects. Bioarc® + oxamyl and Algaefol® + M. chamomilla produced the greatest shoot length and weight. None of the combined treatments affected root length and weight of tomato, except Biozeid® + oxamyl which decreased and Algaefol® + chitosan which increased root weight.