Entomopathogenic Fungi-Mediated Solubilization and Induction of Fe related Genes in Melon and Cucumber Plants

Abstract

Endophytic insect pathogenic fungi have a multifunctional lifestyle; in addition to its well-known function as biocontrol agents, it may also help plants respond to other biotic and abiotic stresses, such as iron (Fe) deficiency. This study explores M. brunneum EAMa 01/58-Su strain attributes for Fe acquisition. Firstly, direct attributes include siderophore exudation (in vitro assay) and Fe content in shoots and in the substrate (in vivo assay) were evaluated for three strains of Beauveria bassiana and Metarhizium bruneum. The M. brunneum EAMa 01/58-Su strain showed a great ability to exudate iron siderophores (58.4% surface siderophores exudation) and provided higher Fe content in both dry matter and substrate compared to the control and was therefore selected for further research to unravel the possible induction of Fe deficiency responses, Ferric Reductase Activity (FRA), and relative expression of Fe acquisition genes by qRT-PCR in melon and cucumber plants.. In addi-tion, root priming by M. brunneum EAMa 01/58-Su strain elicited Fe deficiency responses at transcriptional level. Our results show an early up-regulation (24, 48 or 72 h post inoculation) of the Fe acquisition genes FRO1, FRO2, IRT1, HA1, and FIT as well as the FRA. These results highlight the mechanisms involved in the Fe acquisition as mediated by IPF M. brunneum EAMa 01/58-Su strain.

The non-pathogenic strain Fusarium oxysporum FO12 enhances sunflower and wheat performance by altering the phytohormone profile and soil properties

“…Recently, Beauveria bassiana and Metarhizium brunneum were found to increase Fe and Zn bioavailability, alleviate Fe chlorosis in calcareous soils, and promote growth of various plant species including tomato (Solanum lycopersicum), wheat ( ). Also, B. bassiana and M. brunneum have been shown to induce expression of Fe de ciency-related genes in cucumber (Cucumis sativus) and melon (Cucumis melo) (García-Espinoza et al 2023), and that of immune response-related genes in bread wheat (Triticum aestivum; (González-Guzmán et al 2022). Similarly, Penicillium chrysogenum and P. crustosum have been reported to promote growth in felty germander (Teucrium polium L.; (Hassan 2017), and Aspergillus oryzae to boost plant growth and help suppress Plutella xylostella pests in radish plants (Raphanus sativus L.; (Sun et al 2018).…”