Differential disease outcomes in lettuce plants inoculated with Sclerotinia sclerotiorum and treated with Bacillus amyloliquefaciens (former subtilis) and Trichoderma harzianum

Abstract

Lettuce is a crop which is renowned globally because of the nutritional values it provides as well as economic worth. However, soilborne diseases are known to have an enormous impact on plant cultivation. One of the most common pathogens is Sclerotinia sclerotiorum which can lead to damaging the plant health and production. S. sclerotiorun is a polyphagous pathogen that is hard to manage and eliminate because it can survive into a wide range of temperatures as well as persist in the soil as black sclerotia and emerge when the right conditions are met. To fight this pathogen the farmers, rely heavily on chemical control. In order to investigate possible alternatives to chemical spraying, two biological control agents were applied to lettuce plants after artificial inoculation with S. sclerotiorum. Both Bacillus amyloliquefaciens (former subtilis) and Trichoderma harzianum, were applied at the suggested dose and a significant reduction of disease index was achieved, as compared to the pathogen control. The treatments also showed improvement of important growth parameters, making those two biocontrol agents an effective alternative to chemical control.