Plant Protection, College of Agriculture, University of Misan, AL-Amarah, 62001, Iraq.
College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.
Arch Microbiol. 2024 Jun 3;206(7):286. doi: 10.1007/s00203-024-04014-3.
Controlling the hazard of sclerotia produced by the Sclerotinia sclerotiorum is very complex, and it is urgent to adopt an effective method that is harmonious environmentally to control the disease. Among the six isolates isolated from the rhizosphere of lettuce, the isolate HZA84 demonstrated a high activity in its antagonism towards Sclerotinia sclerotiorum in vitro, and produces siderophore. By amplification of internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF1-α), and RNA polymerase II subunit (RPB2) genes, the isolate HZA84 was identified as Trichoderma asperellum, which was confirmed by analysis of phylogenetic tree. The Scanning electron microscope monitoring detected that the isolate HZA84 spread over the sclerotial surface, thus, damaging, decomposing, and distorting the globular cells of the outer cortex of the sclerotia. The Real-time polymerase chain reaction (RT-qPCR) analysis disclosed the overexpression of two genes (chit33 and chit37) encoding the endochitinase in addition to one gene (prb1) encoding the proteinase during 4 and 8 days of the parasitism behavior of isolate HZA84 on the sclerotia surface. These enzymes aligned together in the sclerotia destruction by hyperparasitism. On the other hand, the pots trial revealed that spraying of isolate HZA84 reduced the drop disease symptoms of lettuce. The disease severity was decreased by 19.33 and the biocontrol efficiency was increased by 80.67% within the fourth week of inoculation. These findings magnify the unique role of Trichoderma in disrupting the development of plant diseases in sustainable ways.
控制核盘菌（Sclerotinia sclerotiorum）产生的菌核的危害非常复杂，迫切需要采用一种有效的、与环境和谐的方法来控制这种疾病。从生菜根际分离出的 6 个菌株中，菌株 HZA84 在体外对核盘菌表现出很高的拮抗活性，并且产生铁载体。通过扩增内部转录间隔区（ITS）、翻译延伸因子 1-α（TEF1-α）和 RNA 聚合酶 II 亚基（RPB2）基因，菌株 HZA84 被鉴定为aspergillus tricoderma，这通过系统发育树分析得到了证实。扫描电子显微镜监测发现，菌株 HZA84 扩散到菌核表面，从而破坏、分解和扭曲菌核外皮层的球形细胞。实时聚合酶链反应（RT-qPCR）分析显示，在菌株 HZA84 寄生菌核表面的 4 天和 8 天内，除了编码蛋白酶的基因 prb1 外，还过度表达了编码内切几丁质酶的两个基因（chit33 和 chit37）。这些酶在菌核的超寄生破坏中协同作用。另一方面，盆栽试验表明，喷洒菌株 HZA84 可减轻生菜菌核病的症状。在接种后的第四周，病情严重程度降低了 19.33%，生物防治效率提高了 80.67%。这些发现突显了木霉在以可持续方式破坏植物病害发展方面的独特作用。
