Induced Suppressiveness to Fusarium oxysporum with Phytostimulation Microorganisms (PSMs) in Hydroponically Grown Tomato

Document Type : Original Article

Authors

1 Department of Microbiology, Faculty of Science, Ain Shams University, Cairo, Egypt

2 Agricultural Microbiological Research Department, Soil, Water and Environment Research Institute, Agricultural Research Center, Giza, Egypt

3 Department of Horticulture, Faculty of Agriculture, Ain Shams University, Cairo, Egypt.

4 Central Lab. for Agricultural Climate, Agricultural Research Center, Dokki, 12411, Giza, Egypt.

Abstract

Phytostimulation microorganisms (PSMs) vis. Bacillus subtilis, Bacillus polymyxa and Trichoderma harzianum were tested for their ability to suppress and control Fusariumroot rot in tomato plants grown in sterilized soilless medium artificially infested with Fusarium oxysporum f. sp. radicis-lycopersici (FORL). Antagonistic activities under laboratory conditions were detected at various degrees of the PSMs against F. oxysporum. T. harzianum was the most potent antagonist and gave an inhibition value of 62%. T. harzianum was also the most effective in decreasing the percentage of pre-emergence damping-off (50%) while B. polymyxa was the most effective one in decreasing the post-emergence (3%) under greenhouse conditions.  PSMS were used as seeds soaking or seedlings inoculation of tomato plants. Pathogenicity test showed that seedlings were more susceptible to F. oxysporum than seeds. PSMS-treated seeds showed that T. harzianum was the superior in controlling Fusarium root rot disease (93% disease control percentage) while in case of seedlings inoculation, B. subtilis gave the highest disease control value (73.3%). B. subtilis and B. polymyxa treated seeds or seedlings were the superior in improving most growth parameters tested in both cases compared to the controls. These results suggest that the increasing of disease control and improvement of tomato growth parameters by seeds or seedlings inoculation with PSMS may contribute to protection of tomato plants against F. oxysporum root rot disease.

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