Fungal Pathogen Fusarium Research Articles

Resolving spatially distinct phytohormone response zones in Arabidopsis thaliana roots colonized by Fusarium oxysporum.

Jasmonic acid (JA), ethylene (ET) and salicylic acid (SA) are the three major phytohormones coordinating plant defense responses, and all three are implicated in the defense against the fungal pathogen Fusarium oxysporum. However, their distinct modes of action and possible interactions remain unknown, in part because all spatial information on their activity is lacking. Here, we set out to probe this spatial aspect of plant immunity by using live-microscopy with newly developed fluorescence-based transcriptional reporter lines. We have created a GreenGate vector collection of Plant Immune system Promoters (GG-PIPs) that allow us to image local activation of immune pathways with single-cell resolution. Using this system, we demonstrate that SA and JA act spatially separate from each other in distinct sets of root cells neighboring the fungal colonization site, while ET contributes to both sets. SA & ET induce the hypersensitive response as a first line of defense, while JA & ET govern active defense against the pathogen in a separate, second line of defense. Such an approach to resolve the plant's immune responses on an individual cell level has been lacking, and this work demonstrates that this microscopy-based approach can contribute to understanding plant immune responses in detail.

Long-Term Intercropping With Nitrogen Management to Improve Soil Quality and Control Crop Diseases.

Long-term positioning experiments have demonstrated significant benefits in agricultural production and environmental protection. Faba bean-wheat intercropping with nitrogen fertiliser can effectively mitigate the occurrence of faba bean wilt disease. Identifying the optimal nitrogen application rate is essential for enhancing the disease control efficacy of intercropping. This study aimed to investigate the long-term effects of varying nitrogen application levels on the physical, chemical, and biological changes in the rhizosphere soil of faba bean under intercropping conditions and to examine their relationship with the incidence of faba bean wilt disease. In a 9-year field experiment, two treatments of faba bean-wheat intercropping for 1 year (IF-1) and 9 years (IF-9) were established to investigate the incidence of faba bean wilt under four nitrogen levels (N0: 0 kg ha-1; N1: 45 kg ha-1; N2: 90 kg ha-1; N3: 135 kg ha-1). Rhizosphere soil from faba bean plants was collected to assess the corresponding physical, chemical, and biological indicators. Long-term intercropping promoted the growth of faba bean plants and effectively controlled faba bean wilt disease by improving soil structure and fertility and soil quality (SQI). Under different nitrogen application levels, certain soil physical properties (moisture content, macroaggregate proportion, MWD, and GMD) and chemical properties (SOM, total carbon, SOC, total nutrients, and available nutrients) peaked under N2 (90 kg ha-1), with SQI showing a similar trend. Additionally, long-term intercropping enhanced enzyme activity in the faba bean rhizosphere, reshaped microbial community composition, maximised the benefits of beneficial microbes, reduced the abundance of the pathogenic fungus Fusarium, and achieved optimal disease control under N2. Under long-term intercropping with nitrogen fertiliser application at N2 (90 kg ha-1), the physical structure of the faba bean rhizosphere soil was significantly improved, soil quality and fertility were enhanced, and the abundance of plant pathogens was reduced by modifying the microbial community composition. This effectively alleviated faba bean disease, promoted healthy plant growth, and maintained soil function.

Computational and experimental approaches to explore defense related enzymes conferring resistance in Fusarium infected chilli plants by regulating plant metabolism through nutritional products.

Nutritional status being the first line of defense for host plants, determines their susceptibility or resistance against invading pathogens. In recent years, the applications of plant nutrient related products have been documented as one of the best performers and considered as alternatives or/and supplements in plant disease management compared to traditional chemicals. However, knowledge about application of plant nutrient related products for the management of destructive fungal pathogen Fusarium oxysporum f.sp. capsici and their impact on the components of the antioxidant defense system, especially in chilli plants, still needs to be discovered. Therefore, in this current study, we aimed to evaluate two nutrient fertilizers viz. Krystafeed and Micro Plus at three different concentrations by soil drenching method for their effects against the Fusarium wilt of chilli and investigate the components of the antioxidant defense system of chilli plants. Correlation and computational analysis on the components of antioxidant defense system in various pathways were performed to predict the suitable binding sites of mineral ions. Results indicated that the combination of Krystafeed and Micro Plus was found the most effective with (27.01, 26.59%) disease incidence, followed by Micro Plus (29.56, 32.35%) and Krystafeed (38.21, 41.15%), both in greenhouse and field conditions, respectively. Moreover, the combination of Krystafeed and Micro Plus significantly increased the concentration of SOD (27.53, 108.96)%, POD (37.29, 45.65)%, CAT (19.33, 95.33)%, H2O2 (22.13, 118.98)%, TPC (27.39, 17.37)%, chlorophyll a (21.80, 35.74)%, chlorophyll b (57.57, 18.25)%, total chlorophyll (30.21, 19.83)%, Tocopherol (13.08, 33.66)%, TrxR (5.03, 36.56)%, MDA (13.84, 54.79)%, ascorbate (4.72, 17.28)%, Proline (5.94, 59.31)%, and phytoalexin (Capsidiol) (11.33, 55.08)% in the treated plants of resistant and susceptible chilli varieties, respectively, as compared to the untreated plants. Pearson's correlation heat-map analysis showed that all the enzymes of antioxidant defense system were found positively correlated with each other. It is concluded that the improvement of crop resistance by the application of plant nutrient related products may be viable alternatives to synthetic chemicals for managing Fusarium wilt disease of chilli and potentially other pathogens.

Functional Analysis of Durum Wheat GASA1 Protein as a Biotechnological Alternative Against Plant Fungal Pathogens and a Positive Regulator of Biotic Stress Defense.

Plants are frequently challenged by a variety of microorganisms. To protect themselves against harmful invaders, they have evolved highly effective defense mechanisms, including the synthesis of numerous types of antimicrobial peptides (AMPs). Snakins are such compounds, encoded by the GASA (Gibberellic Acid-Stimulated Arabidopsis) gene family, and are involved in the response to biotic and abiotic stress. Here, we examined the function of the newly identified TdGASA1 gene and its encoded protein in Triticum durum subjected to different biotic stress-related simulants, such as mechanical injury, methyl jasmonate (MeJA), indole-3-acetic acid (IAA), salicylic acid (SA), hydrogen peroxide (H2O2), as well as infection with pathogenic fungi Fusarium graminearum and Aspergillus niger. We found that in durum wheat, TdGASA1 transcripts were markedly increased in response to these stress simulants. Isolated and purified TdGASA1 protein exhibited significant antifungal activity in the growth inhibition test conducted on eight species of pathogenic fungi on solid and liquid media. Transgenic Arabidopsis lines overexpressing TdGASA1 obtained in this study showed higher tolerance to detrimental effects of H2O2, MeJA, and ABA treatment. In addition, these lines exhibited resistance to Fusarium graminearum and Aspergillus niger, which was linked to a marked increase in antioxidant activity in the leaves under stress conditions. This resistance was correlated with the upregulation of pathogenesis-related genes (AtPDF1.2a, AtERF1, AtVSP2, AtMYC2, AtPR1, AtACS6, AtETR1, and AtLOX2) in the transgenic lines. Overall, our results indicate that TdGASA1 gene and its encoded protein respond ubiquitously to a range of biotic stimuli and seem to be crucial for the basal resistance of plants against pathogenic fungi. This gene could therefore be a valuable target for genetic engineering to enhance wheat resistance to biotic stress.

Volatile organic compounds from Stenotrophomonas geniculata J-0 as potential biofumigants manage bulb rot caused by Fusarium oxysporum in postharvest Lanzhou lily.

The Lanzhou lily bulbs are often vulnerable to postharvest infections by pathogenic fungi, leading to lily bulb rot. This study investigated the ability of volatile organic compounds (VOCs) produced by Stenotrophomonas geniculata J-0 to control the highly pathogenic fungus Fusarium oxysporum BH-7 in postharvest Lanzhou lily bulbs. VOCs of S. geniculata J-0 showed inhibitory effect on the mycelial growth of F. oxysporum BH-7, with a maximum inhibition of 100%. Scanning electron microscope (SEM) observed that VOCs caused a shift in mycelial morphology from elongated and uniform tubular to collapsed and wrinkled. Moreover, VOCs of J-0 significantly reduced pathogenic fungal spore germination and sporulation. Through headspace gas chromatography-ion mobility spectrometry analysis, J-0 emitted 15 volatile compounds. The fumigation test of BH-7 with single pure synthetic compounds showed that 1-penten-3-one had excellent antifungal activity, with an inhibition rate of 100% at 4 μL/L. Additionally, our results revealed 1-penten-3-one destroyed the integrity and increased the permeability of BH-7 mycelial cell membranes, leading to leakage of intracellular electrolytes and substances, a reduction in extracellular pH, a blockage of ergosterol synthesis and an elevation in malondialdehyde content. In vivo experiments, fumigation of 1-penten-3-one at an exceptionally low concentration (4 μL/L) for a very short period of time (0.5h) was effective in delaying the onset and prevalence of postharvest diseases. Hence, this study provides novel antifungal agents to control disease in postharvest Lanzhou lily and enhances our understanding of the biocontrol potential of volatiles from S. geniculata.

Rapid and visual detection of the strawberries pathogenic fungi Fusarium oxysporum and Colletotrichum siamense by one-pot LAMP-CRISPR/Cas12b

Rapid and visual detection of the strawberries pathogenic fungi Fusarium oxysporum and Colletotrichum siamense by one-pot LAMP-CRISPR/Cas12b

Horizontal transfers between fungal Fusarium species contributed to successive outbreaks of coffee wilt disease.

Outbreaks of fungal diseases have devastated plants and animals throughout history. Over the past century, the repeated emergence of coffee wilt disease caused by the fungal pathogen Fusarium xylarioides severely impacted coffee production across sub-Saharan Africa. To improve the disease management of such pathogens, it is crucial to understand their genetic structure and evolutionary potential. We compared the genomes of 13 historic strains spanning 6 decades and multiple disease outbreaks to investigate population structure and host specialisation. We found that F. xylarioides comprised at least 4 distinct lineages: 1 host-specific to Coffea arabica, 1 to C. canephora var. robusta, and 2 historic lineages isolated from various Coffea species. The presence/absence of large genomic regions across populations, the higher genetic similarities of these regions between species than expected based on genome-wide divergence and their locations in different loci in genomes across populations showed that horizontal transfers of effector genes from members of the F. oxysporum species complex contributed to host specificity. Multiple transfers into F. xylarioides populations matched different parts of the F. oxysporum mobile pathogenicity chromosome and were enriched in effector genes and transposons. Effector genes in this region and other carbohydrate-active enzymes important in the breakdown of plant cell walls were shown by transcriptomics to be highly expressed during infection of C. arabica by the fungal arabica strains. Widespread sharing of specific transposons between F. xylarioides and F. oxysporum, and the correspondence of a putative horizontally transferred regions to a Starship (large mobile element involved in horizontal gene transfers in fungi), reinforce the inference of horizontal transfers and suggest that mobile elements were involved. Our results support the hypothesis that horizontal gene transfers contributed to the repeated emergence of coffee wilt disease.

EFFECTIVENESS OF TRICHODERMA SPECIES IN THE MANAGEMENT OF SUGARCANE WILT (FUSARIUM SACCHARI)

Sugarcane is a major cash crop in Pakistan. It has a great contribution in world’s economy. Many diseases cause many losses in yield of sugarcane. Fungi are considered as abundant traitorous pathogens that obstruct the viable growth of sugarcane crop. Wilt disease caused by fungal pathogen Fusarium sacchari caused many losses in sugarcane production in Pakistan. Fusarium sacchari is a causative fungus of wilt in sugarcane. Biocontrol agent Trichoderma spp. used in the management of sugarcane wilt. These bio‐agents help in diseases management and play important role in increasing the crop yield. For this reason, these bio‐agents are used for biological maintaenace of crop diseases and research globally. The use of PDA medium in vitro revealed antagonistic activity of various Trichoderma isolates against the sugarcane wilt pathogen Pathogenicity test also executed to check the most aggressiveness strain of Fusarium spp. to cause disease in sugarcane plant. In vivo, Trichoderma multiply on different substrates and corn Cobbs is good byproduct Trichoderma multiply on it and mix in soil of pots. Pot experiment performed with different treatments to control wilt disease by using of antagonist’s to check disease incidence and disease reduction.

Plant Growth‐Promoting Bacteria Associated With Some Salt‐Tolerant Plants

ABSTRACTGiven the benefits of bacteria associated with the rhizosphere and phytoplane of halophytes, this research focused on examining the plant growth‐promoting characteristics of bacteria isolated from Cressa cretica, Suaeda aegyptiaca, and Alhagi graecorum. From the 33 isolates tested, 9 exhibited plant growth‐promoting traits. Bacillus rugosus strain CS5 and Bacillus sp. strain SS4 exhibited the notable growth inhibition of the pathogenic fungus Fusarium oxysporum, with values of 47% and 45%, respectively. Bacillus sp. strains SS4 and CS1 demonstrated impressive results in solubilizing phosphorus and zinc, respectively, achieving concentrations of 259 and 271 mg L−1. Additionally, Staphylococcus xylosus strain SR2, Bacillus sp. strain SS4, and Bacillus paralicheniformis strain CR1 thrived in nitrogen‐free media. The Priestia filamentosa strain AL4 showed the greatest HCN production, whereas B. paralicheniformis strain CR1 was notable for higher auxin production. The Bacillus sp. strains SS4 and CS1 exhibited greater tolerance than other isolates in a medium containing 600 mM of NaCl. Additionally, inoculating these isolates into soil significantly alleviated the salinity and drought stress on Zea mays seedlings. These findings suggest that further investigation into these strains as microbial inoculants could be beneficial for mitigating salt and drought stress in plants.

Continuous planting American ginseng (Panax quinquefolius L.) caused soil acidification and bacterial and fungal communities’ changes

BackgroundAmerican ginseng is an important herb crop and is widely cultivated in China. However, continuous cropping seriously affects the production of American ginseng, and the reason is still unclear and needs more research. We analyzed the soil microbial alpha diversity and community composition as well as soil physicochemical properties in bulk soils to assess the changes in soil associated with planting American ginseng.ResultsThe cultivation of American ginseng resulted in a significant decrease in soil pH value. The alpha diversity of soil bacteria and fungi was significantly reduced with the increase of American ginseng planting years. Planting American ginseng also largely altered the community composition of soil bacteria and fungi, in particularly, increased the relative abundance of the pathogenic fungus Fusarium, and reduced the relative abundance of some beneficial microorganisms, such as KD4-96, RB41 and Sphingomonas.ConclusionsSoil acidification, reduction of beneficial taxa and accumulation of fungal pathogens, therefore, may lead to the replantation problem of American ginseng.

Long-term garlic‒maize rotation maintains the stable garlic rhizosphere microecology

BackgroundCrop rotation is a sophisticated agricultural practice that can modify the demographic structure and abundance of microorganisms in the soil, stimulate the growth and proliferation of beneficial microorganisms, and inhibit the development of harmful microorganisms. The stability of the rhizosphere microbiome is crucial for maintaining both soil ecosystem vitality and crop prosperity. However, the effects of extended garlic‒maize rotation on the physicochemical characteristics of garlic rhizosphere soil and the stability of its microbiome remain unclear. To investigate this phenomenon, soil samples from the garlic rhizosphere were collected across four different lengths of rotation in a garlic–maize rotation.ResultsThere were notable positive associations between the total nitrogen and total phosphorus contents in the soil and the duration of rotation. Prolonged rotation could increase the maintenance of microbiome α diversity. The number of years of rotation and the soil organic carbon (SOC) content emerged as principal determinants impacting the evolution of the bacterial community structure, with the SOC content playing a pivotal role in sculpting the species diversity within the garlic rhizosphere bacterial community. Additionally, SOC remains predominant in shaping the root-associated bacterial community’s β-nearest taxon index. However, these factors do not have a notable effect on the fungal community inhabiting the garlic rhizosphere. In comparison with monoculture, rotation can amplify the interconnectivity and intricacy of microbial ecological networks. Long-term rotation can further maintain the stability of both microbial ecological networks and interactions between bacterial and fungal communities. It can enlist a plethora of beneficial Bacillus species microorganisms within the garlic rhizosphere to form a biological barricade that aids in safeguarding garlic against encroachment by the pathogenic fungus Fusarium oxysporum, consequently diminishing disease incidence. This study provides a theoretical foundation for the sustainable development of garlic through long-term crop rotation with maize.ConclusionsOur research results indicate that long-term garlic‒maize rotation maintains stable garlic rhizosphere microecology. Our study provides compelling evidence for the role of long-term crop rotation in maintaining microbiota and community stability, emphasizing the importance of cultivating specific beneficial microorganisms to enhance rotation strategies for garlic farming, thereby promoting sustainability in agriculture.

Molecular identification of Fusarium species in commercial vanilla and crop wild relatives in Colombia.

Vanilla is an economically important crop for low-lying humid tropical regions, but cultivated plants face serious phytosanitary problems. Fusarium wilt is a devastating disease affecting vanilla crops, caused by the fungal pathogens Fusarium oxysporum f. sp. vanillae (Fov) and F. oxysporum f. sp. radicis-vanillae (Forv), part of the F. oxysporum species complex (FOSC). We characterized 29 fungal isolates from a vanilla crop and crop wild relatives (CWR) using molecular (EF1-α and ITS-rRNA loci) and morphological traits. Fusarium was the predominant genus, followed by Colletotrichum and Clonostachys. Four Fusarium species were identified: F. oxysporum (37.9%), Fusarium solani (20.7%), Fusarium pseudocircinatum (13.8%) and Fusarium concentricum (10.3%). The latter three species were isolated only from CWR and may represent latent pathogens. Fov was isolated from both the crop and CWR, while a Forv-affiliated isolate was also found in a vanilla crop, marking the first report in the neotropical region. The EF1-α locus provided greater genotype resolution, as well as having reference sequences for Forv. However, the fungal barcode ITS locus is widely applied. We recommend the continued use of both loci for Fusarium diagnosis in vanilla to facilitate early detection and the development of effective integrated crop management strategies.

Bacillus quorum quenching shapes the citrus mycobiome through interkingdom signaling

Microbiomes are sustained through infinite yet mutually interacting microbial communities, with bacteria and fungi serving as the major constituents. In recent times, microbial interventions have become popular for microbiome manipulation to achieve sustainable goals. Whether and how the introduced biocontrol agent drives fungal microbial assemblages (mycobiome) and the role of interkingdom signaling in shaping the microbiome structure and function remain poorly understood. Here, we implemented wild-type (WT) Bacillus subtilis L1–21 and its quorum quenching (QQ) mutants (L1–21Δytnp, and L1–21Δyxel) individually and as consortia to explore the enrichment patterns of key mycobiome members in Huanglongbing (HLB) infected citrus compartments including leaf endosphere, root endosphere, and rhizosphere soil. The application of WT and its QQ mutants produced differential mycobiome enrichment across citrus compartments. Our findings reveal that application of WT B. subtilis enriched beneficial fungi such as Trichoderma (15.82 %) in leaf endosphere. In contrast, pathogenic fungi Fusarium (47.5 %) and Gibberella (0.47 %) involved in citrus root decline were adundant in the L1–21Δytnp treated root endosphere while Nigrospora (11 %) was predominant in L1–21Δyxel treated leaf endosphere, affirming the role of bacterial quorum sensing (QS) molecules in shaping the fungal community composition. In general, based on the fungal functional prediction, fungal pathogens were highly abundant in mutant-treated plants, particularly in leaf endosphere (L1–21Δytnp: 25 %; L1–21Δyxel: 36.35 %) compared to WT (20.93%). Additionally, some fungal members exhibited strong compartment specificity and both mutants induced distinct mycobiome shifts in rhizosphere soil, leaf, and root endopshere. In conclusion, B. subtilis QQ modifies bacterial QS networks facilitating beneficial fungi to establish, while loss of QQ leads to enrichment of pathogenic fungal groups. Our study provides a direct link of perception and regulation of mycobiome through bacterial-based QS and QQ system, and its association with disease outcomes.

BODIPY-mediated photosensitization approach to control maize (Zea mays) pathogenic fungus Fusarium verticillioides

BODIPY-mediated photosensitization approach to control maize (Zea mays) pathogenic fungus Fusarium verticillioides

A novel strategy for obtaining essential oil and flavonoids from Thymus vulgaris L. using polyethylene glycol-ultrasonic pretreatment followed by microwave hydrodistillation and extraction

As a medicinal plant with high economic value, the green and efficient separation of the main components (essential oil (EO) and flavonoids) from Thymus vulgaris L. can enhance its application prospects. The present study developed a polyethylene glycol-ultrasonic pretreatment followed by microwave hydrodistillation and extraction (PEG-U-MHDE) technique to distill EO and extract flavonoids simultaneously. The parameters involved in the PEG-ultrasonic pretreatment and microwave irradiation processes were investigated using single factor and BBD experiments, from which 25 % PEG200/400/600 (1:1:1, v/v/v) was found to have the highest extraction ability. Under the optimal conditions, the yield of EO, apigenin, and baicalein was 3.72 ± 0.15 μL/g, 0.76 ± 0.03 mg/g, and 0.96 ± 0.03 mg/g, respectively. The PEG-U-MHDE showed good stability, recovery, and repeatability for apigenin and baicalein. In addition, the separation efficiency of EO, apigenin, and baicalein obtained by PEG-U-MHDE was 0.19 μL/g/min, 37.85 μg/g/min, and 48.03 μg/g/min, respectively, and the EO contained 81.77 % oxygenated compounds, which were higher than other reference methods. The inhibition rate of EO (concentration of 0.5 μL/mL) against the agricultural pathogenic fungus (Fusarium graminearum) was 36.65 ± 1.28 %, which was speculated to be closely related to its main oxygenated compounds (thymol and carvacrol). In general, PEG-U-MHDE has the advantages of short time and high efficiency, and can realize the simultaneous separation of volatile EO and non-volatile components, which provides a theoretical basis for the comprehensive utilization of natural medicinal plants and crops.

Investigate the efficacy of compounds found in the crude extract of the fungus Aspergillus niger on seeds germination of zucchini

For a long time, fungi have been considered the richest source of bioactive metabolites with numerous applications. Hence, this study was performed to identify various bioactive compounds contained in the ethyl acetate extract of the fungus Aspergillus niger that isolates from infected garlic by using Gas Chromatography-Mass Spectrometry and their effect on seed germination of Zucchini. The current results showed a variety of bioactive compounds such as n-hexadecanoic acid, Hexadecanoic acid, Methyl stearate, Benzoic acid, Hexamethyl-1,3,5-trithiane, and cis-aconitic anhydride with an area percentage of 15.37, 13.93, 6.87, 5.67, 4.75 and 3.59% respectively. The results were performed using the fungus extract that protected the zucchini seed from pathogenic fungi (Botrytis cinerea, Fusarium oxysporum, and Rhizoctonia solani) when soaking for less than 72 h and promoted increased seed germination by high percentage ratio of seeding (66.67%, 80.00%, and 80.00%) respectively, radical length (66.67, 80.00 and 7.67), plumule length (4.67, 7.67 and 6.00) and Number of secondary roots (7.00,8.00 and 7.00) respectively compared with control treatment.

Detection of novel pathogenic variants of Fusarium oxysporum f. sp. lactucae in California

AbstractFusarium wilt, caused by the soilborne fungal pathogen Fusarium oxysporum f. sp. lactucae (FOL), is an economically important disease of lettuce (Lactuca sativa) throughout the world. Four pathogenic races of FOL are reported, though only race 1 is known to exist in the United States. Recently, Californian lettuce growers have expressed increasing concern about Fusarium wilt, as some race 1‐resistant cultivars have exhibited susceptibility, and some susceptible cultivars have displayed reduced disease severity. To determine whether such changes in disease patterns are responses to potentially novel variants, we collected infected plants from commercial fields in the Salinas Valley and Santa Maria regions, isolated the fungus, and conducted a series of pathogenicity tests using a set of FOL race differential cultivars over 2 years (2022 and 2023) in controlled conditions. Pathogenicity tests revealed two new FOL variants that elicited novel disease reaction patterns on the set of differential cultivars that have not been previously described. Isolates Fol621 and Fol621s were less aggressive on race 1‐susceptible Banchu Red Fire, designated Variant‐1. Isolate VSP‐0916 incited severe Fusarium wilt on race 1‐resistant Costa Rica No. 4, designated Variant‐2. Moreover, VSP‐0916 exhibited high aggressiveness and the ability to induce disease in other race 1‐resistant cultivars. This study is the first documentation, to our knowledge, of the occurrence of FOL‐inciting Fusarium wilt on race 1‐resistant lettuce in the United States. Our work provides valuable information critical for the development of Fusarium wilt management strategies, including broad‐spectrum resistance breeding efforts against multiple FOL races.

Comparative genomics of Fusarium species causing Fusarium ear rot of maize.

Fusarium ear rot (FER), caused by the fungal pathogen Fusarium verticillioides, stands as one of the most economically burdensome and pervasive diseases affecting maize worldwide. Its impact on food security is particularly pronounced due to the production of fumonisins, toxic secondary metabolites that pose serious health risks, especially for livestock. FER disease severity is complex and polygenic, with few resistance (R) genes being identified for use in breeding resistant varieties. While FER is the subject of several breeding programs, only a few studies have investigated entire populations of F. verticillioides with corresponding virulence data to better understand and characterize the pathogenomics. Here, we sequenced and compared the genomes of 50 Fusarium isolates (43 F. verticillioides and 7 other Fusarium spp.) that were used to inoculate a diverse maize population. Our objectives were to elucidate the genome size and composition of F. verticillioides, explore the variable relationship between fumonisin production and visual disease severity, and shed light on the phylogenetic relationships among the isolates. Additionally, we conducted a comparative analysis of the nucleotide variants (SNPs) and the isolates' effectoromes to uncover potential genetic determinants of pathogenicity. Our findings revealed several promising leads, notably the association of certain gene groups, such as pectate lyase, with disease severity. These genes should be investigated further as putative alleles for breeding resistant maize varieties. We suggest that, beyond validation of the alleles identified in this study, researchers validate each phenotypic dataset on an individual basis, particularly if considering fumonisin concentrations and when using diverse populations. Our study underscores the importance of genomic analysis in tackling FER and offers insights that could inform the development of resilient maize cultivars. By leveraging advances in genomics and incorporating pathogen populations into breeding programs, resistance to FER can be advanced.

Plant PR1 rescues condensation of the plastid iron-sulfur protein by a fungal effector.

Plant pathogens secrete numerous effectors to promote host infection, but whether any of these toxic proteins undergoes phase separation to manipulate plant defence and how the host copes with this event remain elusive. Here we show that the effector FolSvp2, which is secreted from the fungal pathogen Fusarium oxysporum f. sp. lycopersici (Fol), translocates a tomato iron-sulfur protein (SlISP) from plastids into effector condensates in planta via phase separation. Relocation of SlISP attenuates plant reactive oxygen species production and thus facilitates Fol invasion. The action of FolSvp2 also requires K205 acetylation that prevents ubiquitination-dependent degradation of this protein in both Fol and plant cells. However, tomato has evolved a defence protein, SlPR1. Apoplastic SlPR1 physically interacts with and inhibits FolSvp2 entry into host cells and, consequently, abolishes its deleterious effect. These findings reveal a previously unknown function of PR1 in countering a new mode of effector action.

Enhancing Date Palm (Phoenix dactylifera L.) Resilience: Strategies Against Bayoud Spread in Moroccan Oases

Abstract “Bayoud”, a vascular disease caused by the soilborne fungal pathogen Fusarium oxysporum f. sp. albedinis (Foa), is the principal enemy of palm trees that puts at stake the future of the date palm industry in Morocco. The parasite attacks the palms through the roots and colonizes the entire vascular system, leading to wilt and ultimately palm death. Effective disease management is a major step towards the success of all sustainable development projects in the oasis. This review delineates diverse strategies for managing Bayoud disease, including prophylactic measures, chemical and cultural controls, genetic selection for resistant varieties, and exploration of biochemical and molecular markers. An integrated management approach was proposed that underscores early detection, sustainable agricultural practices, genetic resistance, biological control, community involvement, and continuous research and development. To contain the disease in already-infested areas and prevent its spread to new date palm plantations in oases.