Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Jul 5;14(1):15547.
doi: 10.1038/s41598-024-64056-x.

Biocontrol potential of endophytic fungi against phytopathogenic nematodes on potato (Solanum tuberosum L.)

Rehab Y Ghareeb  1 , Mariusz Jaremko  2 , Nader R Abdelsalam  3 , Mohamed M A Abdelhamid  3 , Eman El-Argawy  4 , Mahmoud H Ghozlan  4
Affiliations

Biocontrol potential of endophytic fungi against phytopathogenic nematodes on potato (Solanum tuberosum L.)

Rehab Y Ghareeb et al. Sci Rep. .

Abstract

Root-knot nematodes (RKNs) are a vital pest that causes significant yield losses and economic damage to potato plants. The use of chemical pesticides to control these nematodes has led to environmental concerns and the development of resistance in the nematode populations. Endophytic fungi offer an eco-friendly alternative to control these pests and produce secondary metabolites that have nematicidal activity against RKNs. The objective of this study is to assess the efficacy of Aspergillus flavus (ON146363), an entophyte fungus isolated from Trigonella foenum-graecum seeds, against Meloidogyne incognita in filtered culture broth using GC-MS analysis. Among them, various nematicidal secondary metabolites were produced: Gadoleic acid, Oleic acid di-ethanolamide, Oleic acid, and Palmitic acid. In addition, biochemical compounds such as Gallic acid, Catechin, Protocatechuic acid, Esculatin, Vanillic acid, Pyrocatechol, Coumarine, Cinnamic acid, 4, 3-indol butyl acetic acid and Naphthyl acetic acid by HPLC. The fungus was identified through morphological and molecular analysis, including ITS 1-4 regions of ribosomal DNA. In vitro experiments showed that culture filtrate of A. flavus had a variable effect on reducing the number of egg hatchings and larval mortality, with higher concentrations showing greater efficacy than Abamectin. The fungus inhibited the development and multiplication of M. incognita in potato plants, reducing the number of galls and eggs by 90% and 89%, respectively. A. flavus increased the activity of defense-related enzymes Chitinas, Catalyse, and Peroxidase after 15, 45, and 60 days. Leaching of the concentrated culture significantly reduced the second juveniles' stage to 97% /250 g soil and decreased the penetration of nematodes into the roots. A. flavus cultural filtrates via soil spraying improved seedling growth and reduced nematode propagation, resulting in systemic resistance to nematode infection. Therefore, A. flavus can be an effective biological control agent for root-knot nematodes in potato plants. This approach provides a sustainable solution for farmers and minimizes the environmental impact.

Keywords: Aspergillus flavus; Defense system response; Efficacy; Egg hatching; Enzymes; GC–MS; Potato; Root knot-nematode; Secondary metabolites.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
(A, B) Polymerase chain reaction (PCR) of Aspergillus flavus with ITS1-ITS4 (598 bp) and (C) Neighbor-joining tree of fungal endophyte A. flavus ON146363 based on ITS1-5.8S-ITS2 rDNA sequences. Confidence values above 50% obtained from a 500-replicate bootstrap analysis shown at the branch nodes. Bootstrap values from the neighbor-joining method were detected. A. flavus (LN482443) was used as the outgroup.
Figure 2
Figure 2
Effect of fungal culture filtrate on (A) larvae mortality and reduction percentages (R%) of the root-knot nematode and on (B) hatchability of M. incognita eggs (R%), under laboratory conditions after 12, 24, 48, 72 h and one week of exposure time. Bar charts are generated using data from five biological replications with two technical replicates per replication. Each bar represents the mean, and the error bar indicates the standard deviation (± SE). This figure was drawn with GraphPad Prism 8 (9.4.1, (458) Serial number: GPS-2567891- 8A130A8A228). The significant of the changes were assessed using SAS one-way ANOVA test. Means with different letters are significantly different (P ≦ 0.05).
Figure 3
Figure 3
The impact of A. flavus culture filtrate on Meloidogyne incognita galls, egg masses, and J2s in 250 g soil of potato plants was examined under greenhouse conditions. Bar charts are generated using data from three biological replications with two technical replicates per replication. Each bar represents the mean, and the error bar indicates the standard deviation (± SE). This figure was drawn with GraphPad Prism 8. The significant of the changes were assessed using SAS one-way ANOVA test. Means with different letters are significantly different (P ≦ 0.05).
Figure 4
Figure 4
Potato plants (A) control healthy without any treatment, (B) control M. incognita, (C) treated with fungal culture filtrate at a concentration of 100% and (D): A. flavus isolated potato.
Figure 5
Figure 5
Efficacy of A. flavus culture filtrate with concentrations (50 and 100%) on (A) Chitinas extracted, (B) Peroxidase enzyme and (C) Catalyse enzyme, from the fresh potato plant inoculated with M. incognita under green-house conditions. Bar charts are generated using data from five biological replications with two technical replicates per replication. Each bar represents mean and error bar indicates standard deviation (± SE). This figure was drawn with GraphPad Prism 8. The significant of the changes were assessed using SAS one-way ANOVA test. Means with different letters are significantly different (P ≦ 0.05).
Figure 6
Figure 6
GC–Ms analysis of A. flavus culture filtrated using an Agilent 7693 series GC system equipped with an OV-5 capillary column and an Agilent 5975C network selective mass detector.
Figure 7
Figure 7
(A) HPLC chromatogram of A. flavus cultural filtrate the mobile phase consisted of a mixture of acetonitrile and 0.3% formic acid (15:85 v/v). The flow rate was set at 0.4 ml/min, and detection was performed at a wavelength of 350 nm. (B) The concentrations of the detected compounds. This figure was drawn with GraphPad Prism 8.
See this image and copyright information in PMC

References

    1. Steglińska A, et al. Metabolite formation by fungal pathogens of potatoes (Solanum tuberosum L.) in the presence of bioprotective agents. Int. J. Environ. Res. Public Health. 2023;20:5221. doi: 10.3390/ijerph20065221. - DOI - PMC - PubMed
    1. Kang Y, et al. Exogenous Glutathione enhances tolerance of the potato (Solanum tuberosum L.) to cadmium stress by regulating the biosynthesis of phenylpropanoid and the signal transduction of plant hormones. Chem. Biol. Technol. Agric. 2023;10:24. doi: 10.1186/s40538-023-00400-z. - DOI
    1. Hijmans RJ. Global distribution of the potato crop. Am. J. Potato Res. 2001;78:403–412. doi: 10.1007/BF02896371. - DOI
    1. Orlando V, et al. Root-lesion nematodes of potato: Current status of diagnostics, pathogenicity and management. Plant Pathol. 2020;69:405–417. doi: 10.1111/ppa.13144. - DOI
    1. Medina IL, et al. Genetic diversity of Meloidogyne spp. parasitising potato in Brazil and aggressiveness of M. javanica populations on susceptible cultivars. Nematology. 2017;19:69–80. doi: 10.1163/15685411-00003032. - DOI

MeSH terms

Substances

-