Sallam Nashwa M A, AbdElfatah Heba-Alla S, Khalil Bagy Hadeel M M, Elfarash Ameer, Abo-Elyousr Kamal A M, Sikora Edward J, Sallam Ahmed
Department of Plant Pathology, Faculty of Agriculture, Assiut University, Assiut, Egypt.
Department of Genetics, Faculty of Agriculture, Assiut University, Assiut, Egypt.
Front Microbiol. 2023 Sep 21;14:1184343. doi: 10.3389/fmicb.2023.1184343. eCollection 2023.
Controlling early blight of tomatoes using endophytic bacteria is an eco-friendly and sustainable approach to manage this common fungal disease caused by , and . Endophytic bacteria are microorganisms that live inside plant tissues without causing harm and can help protect the host plant from pathogens. In this work, twenty endophytic bacterial isolates from tomato healthy plants were tested against pathogenic fungal isolates that caused early blight disease . Out of the 20 tested isolates, three (B4, B7, and B17) were considered effective isolates against the growth of fungal pathogens. The three isolates were recognized as HS-6 (B4), HS-5 (B 7), and HS-4 (B17) using 16s-rDNA sequencing. Different concentrations of bacterial cultural diltrates at 20, 40, and 60% were tested for their antagonistic effects on the development of pathogenic fungi . The lowest dry weights of pathogenic isolates in all bacterial culture filtrates were discovered at 60%. In all culture filtrates, phenolic compounds showed the largest peak area. Under greenhouse conditions, the least disease severity of tomato early blight was found for E. cloacae and its culture filtrate compared to other treatments. Real-time PCR was used to examine the expression pattern of the defense response gene β-1.3 glucanase gene in infected tomato plants with pathogenic fungi (control) as well as its relations with efficient biocontrol agent (). The expression of the gene increased substantially and significantly after three days from the inoculation-infected plants with and while it reached the maximum after five days from the inoculation with , and . Our study concluded that the endophytic bacterial isolate can be considered a promising biocontrol agent for preventing tomato early blight.
利用内生细菌控制番茄早疫病是一种生态友好且可持续的方法，用于管理由[具体病原体1]和[具体病原体2]引起的这种常见真菌病害。内生细菌是生活在植物组织内部且不会造成危害的微生物，能够帮助宿主植物抵御病原体。在这项研究中，对从番茄健康植株中分离出的20株内生细菌菌株进行了测试，以对抗引起早疫病的致病真菌菌株。在20株测试菌株中，有三株（B4、B7和B17）被认为是对真菌病原体生长有效的菌株。使用16s - rDNA测序将这三株菌株鉴定为HS - 6（B4）、HS - 5（B7）和HS - 4（B17）。测试了20%、40%和60%不同浓度的细菌培养滤液对致病真菌生长的拮抗作用。在所有细菌培养滤液中，致病菌株的最低干重出现在60%浓度时。在所有培养滤液中，酚类化合物显示出最大的峰面积。在温室条件下，与其他处理相比，阴沟肠杆菌及其培养滤液对番茄早疫病的病情严重程度影响最小。使用实时PCR检测了感染致病真菌（对照）的番茄植株中防御反应基因β - 1.3葡聚糖酶基因的表达模式，以及它与高效生物防治剂（[具体生物防治剂名称]）的关系。在用[具体生物防治剂1]和[具体生物防治剂2]接种感染的植株接种三天后，该基因的表达大幅显著增加，而在用[具体生物防治剂3]、[具体生物防治剂4]和[具体生物防治剂5]接种五天后达到最大值。我们的研究得出结论，内生细菌菌株[具体菌株名称]可被视为预防番茄早疫病的一种有前景的生物防治剂。
