Eckstien Dikla, Maximov Noga, Margolis Nofet, Raanan Hagai
Department of Plant Pathology and Weed Research, Agricultural Research Organization, Institute of Plant Protection, Gilat Research Center, Rishon LeTsiyon, Israel.
Front Microbiol. 2024 Jul 15;15:1433765. doi: 10.3389/fmicb.2024.1433765. eCollection 2024.
Using microorganisms as biocontrol agents against soilborne plant pathogens is a promising alternative to chemical pesticides. However, only some biocontrol agents have proven effective under field conditions. This study explores the potential of highly resilient microalgae isolated from harsh environments, such as Biological Soil Crusts and agricultural fields in semi-arid regions, as a novel and sustainable approach to biocontrol. Fifty-nine microalgal strains, including thirteen cyanobacteria and forty-six green algae, were isolated and identified. Dual-culture plate assays and toxicity tests of microalgal growth media were conducted to evaluate the antifungal activity of the isolates against eight representative soilborne pathogens. The results showed that many microalgae strains exhibited significant inhibitory effects on the growth of specific fungal pathogens, although the activity varied among different microalgal strains and pathogen species. Some strains even promoted the growth of certain fungi. The lack of a clear pattern in the antifungal activity highlights the complexity and specificity of the interactions between microalgae and soilborne pathogens. An "Inhibition Effectiveness" metric was developed to quantify biocontrol potential based on fungal growth inhibition. The green algal genus , particularly isolates, showed higher antifungal efficacy than other genera. While the inhibitory mechanisms remain unclear, the results demonstrate the promising biocontrol capabilities of microalgae from extreme environments like BSCs. Further research could unlock novel opportunities for sustainable disease management by harnessing specific microalgal strains or synergistic strain combinations targeting soilborne pathogens.
利用微生物作为防治土壤传播植物病原体的生物防治剂是化学农药的一种有前景的替代方法。然而，只有一些生物防治剂在田间条件下被证明是有效的。本研究探索了从恶劣环境中分离出来的高弹性微藻的潜力，如生物土壤结皮和半干旱地区的农田，作为一种新型的可持续生物防治方法。分离并鉴定了59株微藻菌株，包括13株蓝藻和46株绿藻。进行了双培养平板试验和微藻生长培养基的毒性测试，以评估分离株对8种代表性土壤传播病原体的抗真菌活性。结果表明，许多微藻菌株对特定真菌病原体的生长表现出显著的抑制作用，尽管不同微藻菌株和病原体种类之间的活性有所不同。一些菌株甚至促进了某些真菌的生长。抗真菌活性缺乏明确的模式突出了微藻与土壤传播病原体之间相互作用的复杂性和特异性。开发了一种“抑制效果”指标，以基于真菌生长抑制来量化生物防治潜力。绿藻属，特别是分离株，显示出比其他属更高的抗真菌功效。虽然抑制机制尚不清楚，但结果证明了来自生物土壤结皮等极端环境的微藻具有有前景的生物防治能力。进一步的研究可以通过利用针对土壤传播病原体的特定微藻菌株或协同菌株组合，为可持续病害管理带来新的机遇。
