Departamento de Química Agrícola, Edafología y Microbiología, Edificio Severo Ochoa (C-6), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain.
Departamento de Agronomía, Edificio Celestino Mutis (C-4), Campus de Excelencia Internacional Agroalimentario de Rabanales (ceiA3), University of Córdoba, 14014, Córdoba, Spain.
Planta. 2023 Feb 9;257(3):50. doi: 10.1007/s00425-023-04079-2.
FO12 strain enhances Fe deficiency responses in cucumber plants, probably through the production of ethylene and NO in the subapical regions of the roots. Rhizosphere microorganisms can elicit induced systemic resistance (ISR) in plants. This type of resistance involves complex mechanisms that confer protection to the plant against pathogen attack. Additionally, it has been reported by several studies that ISR and Fe deficiency responses are modulated by common pathways, involving some phytohormones and signaling molecules, like ethylene and nitric oxide (NO). The aim of this study was to determine whether the nonpathogenic strain of Fusarium oxysporum FO12 can induce Fe deficiency responses in cucumber (Cucumis sativus L.) plants. Our results demonstrate that the root inoculation of cucumber plants with the FO12 strain promotes plant growth after several days of cultivation, as well as rhizosphere acidification and enhancement of ferric reductase activity. Moreover, Fe-related genes, such as FRO1, IRT1 and HA1, are upregulated at certain times after FO12 inoculation either upon Fe-deficiency or Fe-sufficient conditions. Furthermore, it has been found that this fungus colonizes root cortical tissues, promoting the upregulation of ethylene synthesis genes and NO production in the root subapical regions. To better understand the effects of the FO12 strain on field conditions, cucumber plants were inoculated and cultivated in a calcareous soil under greenhouse conditions. The results obtained show a modification of some physiological parameters in the inoculated plants, such as flowering and reduction of tissue necrosis. Overall, the results suggest that the FO12 strain could have a great potential as a Fe biofertilizer and biostimulant.
FO12 菌株通过在根尖区域产生乙烯和一氧化氮来增强黄瓜植物的缺铁反应。根际微生物可以在植物中引发诱导系统抗性 (ISR)。这种类型的抗性涉及赋予植物对病原体攻击的保护的复杂机制。此外，几项研究报告称，ISR 和缺铁反应受共同途径调节，涉及一些植物激素和信号分子，如乙烯和一氧化氮 (NO)。本研究旨在确定非致病性尖孢镰刀菌 FO12 菌株是否可以诱导黄瓜 (Cucumis sativus L.) 植物的缺铁反应。我们的结果表明，FO12 菌株对黄瓜植物进行根部接种后，在几天的培养后促进植物生长，同时还酸化根际并增强了铁还原酶活性。此外，在 FO12 接种后，无论是在缺铁还是铁充足的条件下，与铁相关的基因，如 FRO1、IRT1 和 HA1，在某些时间都会被上调。此外，还发现该真菌定植在根皮层组织中，促进根尖区域乙烯合成基因的上调和 NO 的产生。为了更好地理解 FO12 菌株对田间条件的影响，在温室条件下，将黄瓜植物接种并种植在石灰质土壤中。获得的结果表明，接种植物的一些生理参数发生了变化，如花的形成和组织坏死的减少。总的来说，结果表明 FO12 菌株可能具有作为铁生物肥料和生物刺激素的巨大潜力。
