Abstract
Calyx spot and vascular wilting are diseases that considerably limit hibiscus production in Mexico. However, the mechanisms of inoculum dissemination are unclear. Seeds are the main method of propagation in hibiscus cultivation. This study aimed to evaluate the seed transmission of fungi associated with calyx spot and vascular wilting in roselle. The study was conducted in Guerrero, Mexico in 2020. Material collected in producing areas of the entity was used. Roselle seeds were collected, disinfected, and cultivated in Petri dishes with potato dextrose agar (PDA) medium until colonies were developed. Isolates were then purified and identified by conventional and molecular methods. Based on foliar symptoms, fungal colony and spore morphology, pathogenicity tests, and ITS and TEF sequence analysis of the isolates, Coniella diplodiella, Curvularia lunanta and Fusarium languescens were the primary pathogens associated with leaf and calyx spot and vascular wilt. Rhizoctonia solani was also identified, but with severity was less than 10%, which resulted in low pathogenic capacity. The sequences of three isolates showed 99 - 100% similarity with C. diplodiella, C. lunanta, R. solani and F. languescens sequences from GenBank by BLAST analysis. The latter is the first report for this crop in Mexico. The study contributes to the understanding of the dynamics of the disease, which is crucial for effectively managing the spread of the pathogens to other regions.