The Influence of Resistance Chemical Inducers Against Anthracnose on Cucumber and Pepper Plants

This study aimed to investigate the effects of boric acid (BA), ascorbic acid (ASA), and salicylic acid (SA) as chemical inducers on the linear growth and sporulation of Colletotrichum orbiculare and Colletotrichum acutatum using cucumber and pepper plants. Scanning electron microscopy (SEM) analysis of SA-treated samples at concentrations of 5mM and 2.5mM against C. orbiculare and C. acutatum , respectively, revealed noticeable deformations, shrinkage, and collapse. Under greenhouse conditions, the efficacy of SA on disease severity index (DSI%) was evaluated, with the Super zad cucumber hybrid F1 cultivar displaying a disease severity of 19.7%, followed by the Rania cucumber hybrid F1 cultivar at 27.57%. In pepper plants, SA treatment demonstrated reduced DSI of anthracnose in both the hot pepper ES 752 F1 and pepper super Ammar F1 cultivars compared to the control treatment. Additionally, SA treatment significantly elevated the levels of non-enzymatic substances, such as free phenolic compounds, total flavonoid content, and total protein, as well as the activities of antioxidative enzymes (peroxidase and polyphenol-oxidase) in both cucumber and pepper cultivars when compared to the controls.