Biological control of the root-knot nematode, Meloidogyne incognita on tomato using bioproducts of microbial origin

The nematicidal potential of four commercial bioproducts containing the bio-agents Bacillus megaterium (Bioarc®), Trichoderma album (Biozeid®), Trichoderma harzianum (Plant Gard®) and Ascophyllum nodosum (Algaefol®) against the root-knot nematode, Meloidogyne incognita, infecting tomato, was assessed in a glasshouse. Their activity was compared with that of oxamyl or carbofuran. The effect of the treatments on the growth parameters of tomato plants was also examined. All treatments were significantly superior over the untreated check in reducing the root galls and J2 of the nematode in the soil, except T. harzianum at 10 and 25 ml/kg soil against J2, which was equal to control treatment. Among the bioproducts, B. megaterium at 10 g/kg soil achieved the highest significant reduction in the number of root galling (89.20%) followed by T. album (87.77%), A. nodosum (86.96%) and T. harzianum (69.79%). The highest rate of the tested bioproducts gave the greatest reduction in galls and significantly higher than that of oxamyl or carbofuran. In addition, all the products found to be high efficient in reducing J2 and caused more than 97% reduction in the soil. The efficacy of the tested bioproducts in reducing the root galls and J2 in the soil increased in a dose dependent manner. Significant increases in shoot length occurred in A. nodosum (25 ml/kg) and T. album (20 g/kg) while T. harzianum (50 ml/kg) significantly decreased the shoot length and weight compared to the untreated inoculated plants. B. megaterium (10 and 20 g/kg) and T. album (5 and 10 g/kg) significantly increased shoot weight. All treatments did not significantly differ from those of untreated inoculated plants except A. nodosum (25 ml/kg) in the case of root length and B. megaterium and A. nodosum at all tested rates in the case of root weight. Generally, the results indicate that the tested microbial products could prove to be one component in integrated root-knot nematode management on tomatoes.

► Efficacy of bionatural products was assessed against Meloidogyne incognita on tomato.
► Bacillus megaterium, Trichoderma album, Trichoderma harzianum and Ascophyllum nodosum reduced galls and J2 in soil.
► The efficacy of bioproducts in reducing nematode increased in a dose dependent manner.
► B. megaterium achieved the highest reduction in root galling.
► The bioproducts could to be one component in integrated root-knot nematode management.