Differential Susceptibility of Bean Pods, Bell Pepper Fruits, and Soybean Leaves Inoculated With Colletotrichum Capsici Enzymes

Abstract

Colletotrichum spp. causes anthracnose diseases in various crops by producing cell wall-degrading enzymes (CWDE’s). Although these enzymes are known to play a role in pathogenesis, their direct effects on host tissues and contribution to disease development remain poorly understood. In this study, Colletotrichum capsici was isolated from bell pepper, and its enzymatic activities were tested on bean pods, bell pepper fruits, and soybean leaves to determine the role of enzymes in disease development. The study focused on characterizing the effects of enzymatic tissue degradation based on symptom appearance, disease incidence percentage, and the infection severity level. Pathogen discs (10 mm) were cultured in Potato Dextrose Broth (PDB), and crude filtrates (CF) were obtained through sequential filtration. Plant tissues were inoculated with CF concentrations of 25%, 50%, 75%, and 100%, arranged in a Completely Randomized Design (CRD), and analyzed using analysis of variance (ANOVA). Results showed that symptom expression occurred as early as 12 hours post-inoculation. At 100% CF, symptoms appeared at 1.75, 2.75, and 0.50 days in bean pods, bell pepper fruits, and soybean leaves, respectively. Disease incidence reached 93.75%, 58.33%, and 100%, while severity reached 26.25%, 21.67%, and 68.33% in bean pods, bell pepper fruits, and soybean leaves, respectively. The study demonstrated that higher CF concentrations consistently accelerated symptom onset and increased both disease incidence and severity. These results confirm that the pathogenicity of C. capsici is closely associated with its enzymatic activity, underscoring the critical role of fungal enzymes in host tissue degradation. This knowledge provides valuable insights for resistance breeding and the development of enzyme-targeted disease management strategies.