Phenotypic and molecular analyses verified the re-isolated fungus as F. pseudograminearum, originating from the basal stems of inoculated plants. Oat crown rot in Tunisia, attributed to F. pseudograminearum, was noted in research by Chekali et al. (2019). In our assessment, this report represents the first instance of F. pseudograminearum causing crown rot in oat crops observed in China. The investigation into oat root rot pathogens and disease management strategies is grounded in this study's findings.

Throughout California's strawberry industry, the occurrence of Fusarium wilt is pervasive, resulting in substantial yield reductions. The FW1 gene bestowed resistance upon cultivars, shielding them from Fusarium wilt, as all strains of Fusarium oxysporum f. sp. proved ineffective. Studies on fragariae (Fof) in California confirm a race 1 characteristic (i.e., no harm to FW1-resistant cultivars), further supported by research by Henry et al. (2017), Pincot et al. (2018), and Henry et al. (2021). Within the Oxnard, California area, a summer-planted, organic strawberry field suffered from severe wilt disease during the fall of 2022. Fusarium wilt symptoms were widespread and consisted of wilting foliage, oddly shaped and profoundly chlorotic leaf blades, and discoloration of the plant's crown. With the Portola cultivar, possessing the FW1 gene and resistant to Fof race 1, the field was planted (Pincot et al. 2018; Henry et al. 2021). Four plants were collected from each of two distinct field locations, in two separate samples. Each sample's crown extract was assessed for the presence of Fof, Macrophomina phaseolina, Verticillium dahliae, and Phytophthora species. The investigation, following the methodology of Steele et al. (2022), incorporated recombinase polymerase amplification (RPA). Using a 1% sodium hypochlorite solution, petioles were surface-sterilized for 2 minutes before being plated onto Komada's medium, which favored the growth of Fusarium species. Considering the perspectives of both Henry et al. (2021) and Komada (1975),. In one sample, the RPA analysis indicated the presence of M. phaseolina, while the other sample yielded negative results for all four pathogens tested. Exuberant, salmon-colored, fluffy mycelia emerged from the petioles of both samples. The colony morphology, including the non-septate, ellipsoidal microconidia (60-13 µm by 28-40 µm) supported on monophialides, presented a pattern similar to that observed in F. oxysporum. Fourteen cultures (P1-P14) were used for single hyphal tip isolation, a procedure designed for isolating and purifying single genotypes. Pure culture amplification using the Fof-specific qPCR method (Burkhardt et al., 2019) failed for all samples, confirming the initial negative RPA findings. check details Three isolates were screened for amplification of translation elongation factor 1-alpha (EF1α), utilizing EF1/EF2 primers (O'Donnell et al., 1998). Sequencing (GenBank OQ183721) of amplicons and comparison using BLAST analysis produced a 100% identity result with an isolate of Fusarium oxysporum f. sp. Melongenae is referenced in GenBank as FJ985297. As reported by Henry et al. (2021), at least one nucleotide was different in this sequence compared to all known strains of Fof race 1. The pathogenicity of five isolates (P2, P3, P6, P12, and P13), along with a control isolate (GL1315) from Fof race 1, was examined on Fronteras (FW1) and Monterey (fw1), a variety which is susceptible to race 1. Five plants corresponding to each isolate cultivar combination were inoculated by dipping their roots in a solution composed of 5 × 10⁶ conidia per milliliter of 0.1% water agar, or sterile 0.1% water agar as a negative control, and then cultivated according to the methodology described by Jenner and Henry (2022). After six weeks, the healthy state of the control plants that had not been inoculated stood in stark contrast to the severe wilting of those plants of both cultivars which were inoculated with the five isolates. The inoculated isolates manifested as identical colonies in the petiole assays, in terms of appearance. The inoculation of plants with race 1 resulted in the appearance of wilt symptoms in Monterey, yet these were absent in Fronteras. With P2, P3, P12, and P13, the experiment was carried out again on the San Andreas FW1 cultivar, and the anticipated results manifested once more. According to our records, this marks the first instance of F. oxysporum f. sp. reported. In California, the fragariae race 2 variety is found. Continued losses from Fusarium wilt are anticipated unless commercially viable cultivars with genetic resistance to this specific Fof race 2 strain become available.

The commercial hazelnut industry in Montenegro, though presently limited, is rapidly increasing in scale. June 2021 saw a severe infection on six-year-old hazelnut plants (Corylus avellana), the Hall's Giant cultivar, affecting over eighty percent of the trees in a 0.3 hectare plantation situated near Cetinje, central Montenegro. 2-3mm in diameter, irregular, brown necrotic spots, sometimes accompanied by a faint chlorotic halo, were a noticeable feature on the leaves. As the disease took its toll, the lesions combined and generated extensive necrotic areas. Unmoving, necrotic leaves remained tethered to the twigs. check details The twigs and branches showed a pattern of longitudinal brown lesions, which resulted in their decline. As part of the findings, there were unopened buds showing necrosis. In the orchard, an absence of fruits was apparent. From the affected leaf, bud, and twig bark tissues, bacterial colonies displaying yellow, convex, and mucoid features were isolated on yeast extract dextrose CaCO3 medium. Subsequently, 14 isolates were carried out for subculture. Pelargonium zonale leaves, exposed to the isolates, exhibited hypersensitive reactions, revealing Gram-negative, catalase-positive, oxidase-negative, obligate aerobic bacteria that hydrolyzed starch, gelatin, and esculin, and failed to reduce nitrate or grow at 37°C or in the presence of 5% NaCl. These isolates displayed a biochemical profile consistent with that of the reference strain, Xanthomonas arboricola pv. Corylina (Xac) NCPPB 3037: a recordable identifier within the system. All 14 isolates, along with the reference strain, yielded a 402 base pair amplification product when employing the primer pair XarbQ-F/XarbQ-R (Pothier et al., 2011), underscoring their taxonomic placement within X. arboricola species. PCR analysis, using the XapY17-F/XapY17-R primer pair (Pagani 2004; Pothier et al., 2011), confirmed the identity of the isolates, revealing a unique 943 bp band, a hallmark of Xac. A set of primers, as described by Hajri et al. (2012), was utilized for the amplification and sequencing of the partial rpoD gene sequence from the two selected isolates, RKFB 1375 and RKFB 1370. The DNA sequences of the isolates (GenBank Nos. ——) indicated the following. Xac strains CP0766191 and HG9923421, isolated from hazelnut trees in France, and HG9923411, found in the USA, show a remarkable 9947% to 9992% rpoD sequence identity to OQ271224 and OQ271225. By spraying young shoots (20 to 30 cm in length, featuring 5 to 7 leaves) onto 2-year-old potted hazelnut plants (cultivar), the pathogenicity of all isolates was established. check details Hall's Giant received three separate applications of a bacterial suspension (108 CFU/mL of sterile tap water), delivered by a handheld sprayer. Sterile distilled water (SDW) was used as the negative control, in contrast to the NCPPB 3037 Xac strain, which acted as the positive control. Within a greenhouse, inoculated shoots were kept in plastic bags to maintain high humidity, at a temperature of 22-26°C, for 72 hours. On the leaves of all inoculated shoots, lesions surrounded by a halo appeared 5 to 6 weeks after inoculation, but leaves sprayed with SDW maintained their symptom-free status. Using the primer set developed by Pothier et al. (2011), PCR analysis confirmed the identity of the re-isolated pathogen from the necrotic test plant tissue, thereby verifying the validity of Koch's postulates. Based on the combination of pathogenic, biochemical, and molecular characteristics, the isolates obtained from hazelnut plants located in Montenegro were identified as X. arboricola pv. Corylina, a captivating creature, graces the scene with its presence. This report details the initial incident of Xac's effect on hazelnut production in this nation. Due to the presence of the pathogen under conducive environmental factors, the hazelnut production in Montenegro can experience considerable economic losses. In this vein, phytosanitary steps need to be undertaken to forestall the entry and spreading of the pathogen into other regions.

Spider flower (Tarenaya (Cleome) hassleriana (Chodat) Iltis, Cleomaceae), a remarkably ornamental landscape plant, features a prolonged period of flowering, thereby holding a crucial position in horticultural practices (Parma et al. 2022). During May 2020 and April 2021, the spider flower plants within the Shenzhen public garden (2235N and 11356E) experienced a severe manifestation of powdery mildew. The infection rate among the plant specimens reached approximately 60%, marked by irregular white patches appearing on the adaxial side of diseased leaves, spanning the entire spectrum of leaf maturity. Infected leaves, in severe infections, displayed a pattern of premature drying and defoliation. Microscopic views of mycelia showcased irregularly lobed structures, the hyphal appressoria. Straight, unbranched conidiophores (n = 30), measuring 6565-9211 m in length, were composed of two to three cells. Conidiophores supported individual conidia, cylindrical to oblong, with measurements ranging from 3215 to 4260 µm by 1488 to 1843 µm (mean 3826 by 1689, n=50), lacking distinct fibrosin bodies. The presence of chasmothecia went unobserved. Employing the ITS1/ITS5 primer set, the internal transcribed spacer (ITS) region was amplified, whereas the NL1/NL4 primer set was used for the amplification of the 28S rDNA. Representative ITS and 28S rDNA sequences, with their corresponding GenBank accession numbers, are listed. BLASTN analysis of ITS sequence MW879365 and 28S rDNA sequence MW879435 revealed a 100% match to Erysiphe cruciferarum sequences in GenBank, with corresponding accession numbers.