Biological Products and Foliar Fertilizers for the Control of Sclerotinia sclerotiorum in Beans (Phaseolus vulgaris L.) in Brazil

In this study, the effectiveness of alternative products for the control of white mold (Sclerotinia sclerotiorum) in common bean plants under in vitro and greenhouse conditions. For the in vitro tests, the phytopathogen was grown in potato dextrose agar (PDA) medium amended with three concentrations of seven treatment products (50%, 100%, and 200% of the recommended dose) or on the plain culture medium (control). A completely randomized and factorial design (8 products × 3 concentrations) was. Mycelial growth was evaluated to determine the mycelial growth rate (MGR) and the percentage inhibition of mycelial growth. Greenhouse experiments were conducted using a randomized block design in a factorial scheme design (8 products × 2 application timings- 5 days before or 3 days after inoculation), and disease severity was determined using the area under the disease progress curve (AUDPC). The area under the disease progression curve (AUDPC) was used to determine the disease severity. Dimoxystrobin + boscalide and Trichoderma harzianum completely suppressed mycelial growth at all concentrations (100% inhibition), while the combination of T. harzianum + T. asperellum + Bacillus amyloliquefaciens showed high inhibition (> 90%) across concentrations. Potassium phosphite, copper sulfate, and polyphenol exhibited partial and dose-dependent inhibitory effects. Greenhouse experiments were conducted in a randomized block design in a factorial scheme (8 products × 2 application timings- 5 days before or 3 days after inoculation), and disease severity was assessed using the area under the disease progress curve (AUDPC). Preventive application of dimoxystrobin + boscalide resulted in the greatest reduction in disease severity, while the other treatments showed limited or variable effects.