Applied Soil Ecology 56 (2012) 58–62 Contents lists available at SciVerse ScienceDirect Applied Soil Ecology journa l h o me page: www.elsevier.com/locate/apsoil Biological control of the root-knot nematode, Meloidogyne incognita on tomato using bioproducts of microbial origin M.A. Radwan ∗ , S.A.A. Farrag, M.M. Abu-Elamayem, N.S. Ahmed Pesticide Chemistry and Technology Department, Faculty of Agriculture, University of Alexandria,Egypt a r t i c l e i n f o Article history: Received 21 June 2011 Received in revised form 5 February 2012 Accepted 8 February 2012 Keywords: Biological control Microbial products Meloidogyne Bacillus Trichoderma Ascophyllum a b s t r a c t 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 J 2 of the nematode in the soil, except T. harzianum at 10 and 25 ml/kg soil against J 2 , 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 J 2 and caused more than 97% reduction in the soil. The efficacy of the tested bioproducts in reducing the root galls and J 2 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. Crown Copyright © 2012 Published by Elsevier B.V. All rights reserved. 1. Introduction Root-knot nematodes (Meloidogyne spp.) are among the most economically damaging genera of plant parasitic nematodes on horticultural and field crops, causing an estimated US$100 billion loss globally on an annual basis (Oka et al., 2000). They are dis- tributed worldwide and are obligate parasites of roots of thousands of plant species. However, more than 90 species of Meloidogyne have been described, where Meloidogyne incognita (Kofoid & White) Chitwood, Meloidogyne javanica (Treub) Chitwood, and Meloidog- yne arenaria (Neal) Chitwood are extremely polyphagous apomictic species. These three species are found worldwide, typically in trop- ical and subtropical areas but are also present in more temperate areas especially in protected cultivation (Hunt and Handoo, 2009). ∗ Corresponding author at: Pesticide Chemistry and Technology Department, Fac- ulty of Agriculture (El-Chatby), University of Alexandria, Alex., Egypt. Tel.: +20 03 5905029; fax: +20 03 5902766. E-mail address: mohamedradwan52008@hotmail.com (M.A. Radwan). Root-knot nematodes cause considerable average annual vegetable yield losses of about 10% (Koenning et al., 1999). However, heavy infestations of these nematodes can lead to yield losses of over 30% in highly susceptible vegetable crops (Sikora and Fernández, 2005). Establishment of root-knot nematodes in deep-rooted perennial crops makes their management and control difficult, especially with the limited options available. Several control measures were employed to control root-knot nematodes in infested areas. The traditional method of nematode control is based mainly on chemical nematicides. However, the potential negative impact on environment and ineffectiveness after prolonged use have led to a total ban or restricted use of most chem- ical nematicides and an urgent need for safe and more effective alternatives (Zukerman and Esnard, 1994). Researchers all over the world are engaged in standardizing the root-knot nematode management strategies by following non- chemical and eco-friendly alternatives such as sanitation, soil management, organic amendments, fertilization, biological con- trol and heat-based methods to stabilize vegetable production (Collange et al., 2011). Biological control promises to be one of 0929-1393/$ – see front matter. Crown Copyright © 2012 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.apsoil.2012.02.008