Identification of the Pathogen Causing Leaf Spot in Zinnia elegans and Its Sensitivity to Five Fungicides

• Published in: Pathogens (Basel) Vol. 11; no. 12; p. 1454
• Main Authors: Liu, Yu, Yao, Qiuyu, Liang, Shuang, Li, Cheng, Chen, Xiangsheng, Li, Zhong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.12.2022; MDPI
• Subjects: Difenoconazole; Disease; Disease control; Flowers & plants; Fungicides; Growth rate; leaf spot disease; Leafspot; Leaves; Morphology; Nigrospora musae; Ornamental plants; Pathogens; Pesticides; Phylogenetics; Ribosomal DNA; Tebuconazole; Toxicity; Zinnia elegans; Zinnia elegans Jacq; Beijing China; China; leaf spot disease; fungicides; Nigrospora musae; Zinnia elegans Jacq
• ISSN: 2076-0817; 2076-0817
• DOI: 10.3390/pathogens11121454

Jacq. is an important, globally cultivated ornamental plant. In August 2021, a leaf spot disease was observed in zinnia in Shibing County, Guizhou, China, with an incidence of approximately 60%. Pathogens were isolated and purified from the infected leaves by tissue isolation, and pathogen strain BRJ2 was confirmed as the pathogen causing the leaf spot. Based on morphology and , , and sequence analyses, the pathogen was identified as (McLennan and Hoëtte). The mycelial growth rate method was used to determine the in vitro toxicity of five fungicides to the pathogen. The results showed that 10% difenoconazole provided the strongest inhibitory effect on , with a concentration for 50% of maximal effect (EC ) of 0.0658 mg/L; 75% trifloxystrobin·tebuconazole had the second greatest effect, with an EC of 0.1802 mg/L. This study provides the first report that caused leaf spot disease in and provides important guidance for the effective prevention and control of this disease in Guizhou.