Effect of Rhizobacteria on Yield of Hydroponically Grown Tomato Plants

In this study, plant growth-promoting rhizobacteria (PGPR), selected for their ability to promote plant growth and for the biological control of crown and root rot caused by Fusarium oxysporum f. sp. radicis-lycopersici (FORL), were tested on tomato production in perlite under greenhouse conditions. Four PGPR isolates (TR 2/1: Pseudomonas fluorescens bv3, TR 18/1: Pseudomonas fluorescens, TR 21/1: Pseudomonas putida, 14/1y: Pseudomonas fluorescens bv5) selected based on the results of in vitro and in vivo tests from a collection of fifty PGPR strains, were compared with non PGPR inoculated control treatment. A resistant and a sensitive to FORL tomato variety were used. Plants were grown under healthy conditions without FORL inoculation. Seeds were sown on 11 January 2010 and transplanting was realised on 26 February 2010. Harvest period lasted six weeks from 24 May to 2 July. Cumulative fruit weight and number were measured weekly. Tomato plants inoculated with rhizobacteria gave significantly higher yield compared to the control treatment in the first 4 weeks of harvesting period.