Qi Yanxiang, Zhao Hong, Zhang Zhaojing, Ouyang Yanfei, Zhang Xin
Hainan Provincial Key Laboratory of Pests Detection and Control for Tropical Agriculture, Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China.
State Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China.
Microorganisms. 2025 May 30;13(6):1285. doi: 10.3390/microorganisms13061285.
Foliar diseases caused by various fungi severely affect the yield and quality of banana crops. This study was conducted to clarify the biological characteristics of (teleomorph: ), a pathogen reported in 2023 as a new etiological agent of leaf spot in the banana variety 'Pisang Mas' (, AA group) in Hainan Province, China, and to screen effective fungicides for its control. The results indicated that banana leaf extract agar (BLEA) and cornmeal agar (CMA) were the best media for the growth and sporulation of the pathogen, respectively. The pathogen grew best on a Czapek's agar (CZA) medium with sucrose as a carbon source and yeast extract as a nitrogen source, while the optimal carbon and nitrogen sources for sporulation were lactose and beef extract, respectively. The pathogen could grow within a temperature range from 5 °C to 35 °C, and the optimal temperatures for growth and sporulation were 30 °C and 25 °C, respectively. Exposure to 50 °C for 10 min was lethal. Additionally, the pathogen could grow and sporulate within pH ranges of 4 to 10 and 4 to 9, respectively, and the optimal pH values for growth and sporulation were 5 and 8, respectively. The optimal photoperiods for growth and sporulation were 16 h light/8 h dark and 24 h light, respectively. Among the 12 tested fungicides, 500 g/L of iprodione SC showed the highest toxicity against , with an EC value of 0.08 μg/mL, followed by 30% difenoconazole-azoxystrobin SC and 125 g/L of epoxiconazole SC, with EC values of 0.13 μg·mL and 0.20 μg/mL, respectively. A fungicide containing 40% chlorothalonil SC had the poorest fungicidal activity, with an EC value of 155.98 μg/mL. An artificial inoculation pot experiment showed that 125 g/L of epoxiconazole SC at 250 μg/mL, 500 g/L of iprodione SC at 1667 μg/mL, and 30% difenoconazole-azoxystrobin SC at 250 μg/mL provided a protective control efficacy of 100% against , while 125 g/L of epoxiconazole SC at 250 μg/mL and 500 g/L of iprodione SC at 1667 μg/mL provided a curative control efficacy of greater than 60%. This study clarified the optimal conditions for the mycelial growth and sporulation of isolated from banana and screened out fungicides with effective inhibitory activities. These results can provide guidance for field applications and the management of leaf spot caused by in banana.
由多种真菌引起的叶部病害严重影响香蕉作物的产量和品质。本研究旨在阐明2023年报道的一种病原菌（有性型： ）的生物学特性，该病原菌是中国海南省香蕉品种‘Pisang Mas’（ ，AA组）叶斑病的新病原，并筛选有效的杀菌剂对其进行防治。结果表明，香蕉叶提取物琼脂（BLEA）和玉米粉琼脂（CMA）分别是该病原菌生长和产孢的最佳培养基。该病原菌在以蔗糖为碳源、酵母提取物为氮源的察氏琼脂（CZA）培养基上生长最佳，而产孢的最佳碳源和氮源分别是乳糖和牛肉提取物。该病原菌能在5℃至35℃的温度范围内生长，生长和产孢的最适温度分别为30℃和25℃。在50℃下暴露10分钟可致死。此外，该病原菌分别能在pH值为4至10和4至9的范围内生长和产孢，生长和产孢的最适pH值分别为5和8。生长和产孢的最佳光周期分别为16小时光照/8小时黑暗和24小时光照。在12种供试杀菌剂中，500克/升异菌脲悬浮剂对该病原菌的毒性最高，EC值为0.08微克/毫升，其次是30%苯醚甲环唑 - 嘧菌酯悬浮剂和125克/升氟环唑悬浮剂，EC值分别为0.13微克·毫升和0.20微克/毫升。含有40%百菌清悬浮剂的杀菌剂杀菌活性最差，EC值为155.98微克/毫升。人工接种盆栽试验表明，250微克/毫升的125克/升氟环唑悬浮剂、1667微克/毫升的500克/升异菌脲悬浮剂和250微克/毫升的30%苯醚甲环唑 - 嘧菌酯悬浮剂对该病原菌的保护防治效果达100%，而250微克/毫升的125克/升氟环唑悬浮剂和1667微克/毫升的500克/升异菌脲悬浮剂的治疗防治效果大于60%。本研究阐明了从香蕉中分离出的该病原菌菌丝生长和产孢的最佳条件，并筛选出具有有效抑制活性的杀菌剂。这些结果可为香蕉叶斑病的田间应用和防治提供指导。
