Derikvand Fatemeh, Bazgir Eidi, El Jarroudi Moussa, Darvishnia Mostafa, Mirzaei Najafgholi Hossein, Laasli Salah-Eddine, Lahlali Rachid
Plant Pathology, Faculty of Agriculture, Lorestan University, Lorestan, Khorramabad 68151-44316, Iran.
Water, Environment and Development Unit, Department of Environmental Sciences and Management, UR SPHERES Research Unit, University of Liège, 6700 Arlon, Belgium.
J Fungi (Basel). 2023 Aug 5;9(8):828. doi: 10.3390/jof9080828.
, a notorious fungal pathogen responsible for the devastating brown rot disease afflicting apples, wreaks havoc in both orchards and storage facilities, precipitating substantial economic losses. Currently, chemical methods represent the primary means of controlling this pathogen in warehouses. However, this study sought to explore an alternative approach by harnessing the biocontrol potential of bacterial isolates against brown rot in apple trees. A total of 72 bacterial isolates were successfully obtained from the apple tree rhizosphere and subjected to initial screening via co-cultivation with the pathogen. Notably, eight bacterial isolates demonstrated remarkable efficacy, reducing the mycelial growth of the pathogen from 68.75 to 9.25%. These isolates were subsequently characterized based on phenotypic traits, biochemical properties, and 16S rRNA gene amplification. Furthermore, we investigated these isolates' production capacity with respect to two enzymes, namely, protease and chitinase, and evaluated their efficacy in disease control. Through phenotypic, biochemical, and 16S rRNA gene-sequencing analyses, the bacterial isolates were identified as , , sp., , and . In dual culture assays incorporating , and exhibited the most potent degree of mycelial growth inhibition, achieving 68.75 and 9.25% reductions, respectively. All the bacterial isolates displayed significant chitinase and protease activities. Quantitative assessment of chitinase activity revealed the highest levels in strains AP5 and AP13, with values of 1.47 and 1.36 U/mL, respectively. Similarly, AP13 and AP6 exhibited the highest protease activity, with maximal enzyme production levels reaching 1.3 and 1.2 U/mL, respectively. In apple disease control assays, and strains exhibited disease severity values of 12.34% and 61.66% (DS), respectively, highlighting their contrasting efficacy in mitigating disease infecting apple fruits. These findings underscore the immense potential of the selected bacterial strains with regard to serving as biocontrol agents for combatting brown rot disease in apple trees, thus paving the way for sustainable and eco-friendly alternatives to chemical interventions.
是一种臭名昭著的真菌病原体，会引发危害苹果的毁灭性褐腐病，在果园和储存设施中造成严重破坏，导致巨大经济损失。目前，化学方法是控制仓库中这种病原体的主要手段。然而，本研究试图探索一种替代方法，即利用细菌分离株对苹果树褐腐病的生物防治潜力。总共从苹果树根际成功获得了72株细菌分离株，并通过与病原体共培养进行初步筛选。值得注意的是，8株细菌分离株表现出显著效果，将病原体的菌丝生长从68.75%降低到9.25%。随后根据表型特征、生化特性和16S rRNA基因扩增对这些分离株进行了鉴定。此外，我们研究了这些分离株产生两种酶（即蛋白酶和几丁质酶）的能力，并评估了它们在病害防治中的效果。通过表型、生化和16S rRNA基因测序分析，这些细菌分离株被鉴定为、、 属、、和。在双培养试验中，和表现出最强的菌丝生长抑制程度，分别使菌丝生长减少了68.75%和9.25%。所有细菌分离株都表现出显著的几丁质酶和蛋白酶活性。几丁质酶活性的定量评估显示，AP5和AP13菌株中的水平最高，分别为1.47和1.36 U/mL。同样，AP13和AP6表现出最高的蛋白酶活性，最大酶产生水平分别达到1.3和1.2 U/mL。在苹果病害防治试验中，和菌株的病害严重程度值分别为12.34%和61.66%（病害严重度），突出了它们在减轻苹果果实感染病害方面的不同效果。这些发现强调了所选细菌菌株作为防治苹果树褐腐病生物防治剂的巨大潜力，从而为化学干预的可持续和环保替代方案铺平了道路。
