Identification and fungicide sensitivity of Colletotrichum incanum, the causal agent of anthracnose disease of balloon flower, in vitro conditions

Abstract

Anthracnose disease, caused by Colletotrichum incanum, has emerged and affected the production of balloon flower (Platycodon grandiflorus) in Viet Nam. The current study aims to characterize C. incanum and evaluate its sensitivity to fungicides. C. incanum was identified based on morphological characteristics and phylogenetic analyses of internal transcribed spacer (ITS) sequences. The study revealed that Potato Dextrose Agar (PDA) was the most suitable medium for the growth of C. incanum. The optimal conditions were observed at temperatures ranging between 25-28 °C and pH levels of 6.5-7.0. Antracol 70WP at a concentration of 3.00 g L−1, Tilt Super® 300EC at 0.03 ml L−1, and Ridomil Gold® 68WG at 4.5 g L−1 exhibited high efficacy in inhibiting the growth and development of C. incanum isolates under in vitro conditions. It’s worth noting that this study marks the first report of C. incanum causing anthracnose disease in balloon flower in Viet Nam.