Effect of ammonium/nitrate ratio in nutrient solution on control of Fusarium wilt of tomato by Trichoderma asperellum T34

Authors

  • C. Borrero,

    Corresponding author
    1. Department of Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería Agronómica, Universidad de Sevilla, Ctra Utrera km 1, E-41013 Sevilla
      E-mail: cborrero@us.es
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  • M.I. Trillas,

    1. Department of Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Avda Diagonal 645, E-08028 Barcelona, Spain
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  • A. Delgado,

    1. Department of Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería Agronómica, Universidad de Sevilla, Ctra Utrera km 1, E-41013 Sevilla
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  • M. Avilés

    1. Department of Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería Agronómica, Universidad de Sevilla, Ctra Utrera km 1, E-41013 Sevilla
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E-mail: cborrero@us.es

Abstract

The behaviour of Fusarium oxysporum f.sp. lycopersici (Fol) and the effectiveness of the microbial control agent Trichoderma asperellum strain T34 were examined in hydroponically grown tomato plants under five ammonium/nitrate ratios. The results showed that disease severity was reduced by the action of T34 under increasing concentrations of ammonia. Furthermore, rhizosphere F. oxysporum populations decreased with T34 application. The presence of T34 augmented leaf nitrogen concentration in treatments infested with Fol. In addition, T34 application reduced iron concentration in tomato leaves at high ammonium/nitrate ratios and reduced the severity of Fusarium wilt at high iron and nitrogen leaf concentrations.

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