Potencial biofungicida del extracto orgánico de Commelina diffusa contra Mycosphaerella fijiensis, agente causal de la Sigatoka Negra en el cultivo de banano

Abstract

Ecuador is known for its rich biological diversity, encompassing a wide range of animal and plant species. Among these, Commelina diffusa Burm. f., a member of the Commelinaceae family, stands out for its potential beneficial properties. Mycosphaerella fijiensis, the pathogen responsible for Black Sigatoka, severely damages banana plantations in Ecuador and other parts of the world, causing significant annual losses. The disease induces necrotic streaks on leaves, reducing photosynthetic capacity and decreasing crop yield. Ecuadorian bananas are widely consumed on a global scale, directly impacting millions of people. Given this background, Commelina diffusa has been studied for its antioxidant, antibacterial, analgesic, and nutraceutical properties. The aim of this study is to determine whether the extract of C. diffusa possesses sufficient antimicrobial and antifungal properties to develop an effective bioproduct against Black Sigatoka, offering a natural and sustainable solution for controlling the pathogen. The study began with the identification of the plant, herbarium preparation, and extraction of the plant material. Phytochemical analyses were also conducted to assess the components present in the organic extract of C. diffusa. Mayer and Wagner assays detected alkaloids, while Dragendorff and Hager tests were negative. For flavonoids, the Shinoda and Sulfuric Acid tests confirmed the presence of flavones and flavanones, validating previous research findings. The inhibitory capacity of the organic extract of C. diffusa against Mycosphaerella fijiensis was evaluated using the in vitro microdilution technique in multi-well plates, following the standards of the Clinical and Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Although the method showed certain limitations for this type of microorganism, further research will be conducted.