Bio-management of sclerotinia rot disease on beans using different mutualistic fungal isolates and marine algae [electronic resource].

Includes reference

The biological control potential of four different candidate biocontrol agents, three isolates belonging to genus Trichoderma and an isolate of mutualistic entophytic Fusarium oxysporum (Fo162), in addition to four different marine algae (Ulva fasciata, Gelidium crinale, Jania rubens and Coralline elongata) were determined against Sclerotinia Sclerotiorum on bean plants under green house conditions. The influence of either tested mutualistic fungi or algae on the growth criteria i.e. plant height, fresh and dry roots and shoot weight as well as on Sclerotinia disease severity were compared with Uniform fungicide (Mefenoxam and Azoxystrdbin). In order to infer size the possible mode of action that can be involved in the possible tri-trophic interactions between S. sclerotiorum, bean plants and the tested bio-control agents, the chemical assessment of some vital enzymes and substances i.e. peroxidase, poly phenoloxidase and total sugar contents had been done. The results revealed that all the tested bio- and chemical- agents affected positively plant heights, fresh weight and dry weight of both roots and shoots of treated plants. In general, marine algae were superior to the other biocontrol fungi with regard to their influence on growth parameters. Comparing to cotJtrol plants, inoculated only with the pathogen, the all scanned bio-agents fungi and algae reduced significantly the disease severity on treated plants. The highest disease reduction was observed with mutualistic fungi in general and with Trichoderma hamatum isolate Thm particularly. The obtained results from the chemical assay revealed the highest total sugar concentration was detected with plants treated with the tested seaweeds (marine algae). In contrary, the results indicated that highest activity for antioxidant enzymes i.e. peroxidase and poly phenoloxidase were recorded mainly with the tested biological mutua/istic fungi. In conclusion, the biomanagement technique using either specific bio-control isolates i.e. Trichoderma hamatum (Thm), T. viride (Tv), T. harzianum (T.sp.), Fusarium oxysporum (fo162), or promising seaweeds i.e. Ulva fasciata, Gelidium crinale, Jania rubens and Coralline elongata is a useful tool in controlling the Sclerotinia rot disease of bean plants and therefore it can be considered

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