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Petri dishes remained in darkness at 25 degrees Celsius, incubated for a total duration of five days. The single hyphal tip procedure was executed to yield pure cultures grown on PDA media. From the 14-day incubation, fifteen pure isolates were extracted. Two days of black light exposure were used to trigger sporulation in the isolated fungal samples. White, cotton-like mycelium was a prevalent early feature in all isolates, subsequently evolving into a dark, emerald green color (Figure 1b). A microscope revealed straight primary conidia organized in simple or branched chains. The conidia, which were obclavate, long ellipsoidal in shape, displayed a moderate size (195-439 micrometers in length, 71-172 micrometers in width), and possessed septa, primarily in a few longitudinal patterns. In conclusion, the conidium’s body may become narrower, resulting in a secondary conidium formation (Figure 1c) (Woudenberg et al., 2013). The isolates were categorized as Alternaria species on the basis of their observed colony and conidia morphology. In the study by Woudenberg et al. (2013),. DNA extraction and sequencing of the ITS (internal transcribed spacer; Chou, H.H. and Wu, W.S. 2002), TEF (translation elongation factor; O’Donnell et al., 1998), and RPB2 (RNA polymerase II second largest subunit; Liu et al., 1999) gene regions were performed on five randomly chosen isolates. Across all isolates, the DNA sequences sampled from each marker were without variation. Within the MEGA X platform, ClustalX (Kumar et al., 2018) was employed to develop consensus sequences and alignment. Within GenBank, the following consensus sequences were deposited with their respective accession numbers: ITS, ON982232; TEF, ON983964; and RPB2, ON983963. Employing concatenated sequences (Drummond et al., 2012; Maharachchikumbura et al., 2014), a multilocus phylogenetic tree was inferred via Bayesian inference in Beast software (version 18.4). The isolates from our study were clustered with those of Alternaria alternata, thereby confirming their identity (Figure 2). Healthy broccoli plants were cultivated in sterile soil for six weeks, forming a critical element of the procedures adhering to Koch’s postulates. Suspended in sterile distilled water (1106 conidia/ml) were the fungal conidia, which were subsequently sprayed onto the leaves to effect inoculation. For the control group, the application consisted solely of sterile distilled water. The plants were cared for under specific environmental parameters, which included a temperature of 28 degrees Celsius and a relative humidity exceeding 85% (Sigillo et al., 2020). Seven days post-inoculation, the plants manifested both chlorosis and necrosis. At the conclusion of a ten-day treatment regimen, all treated leaves demonstrated the presence of brown, circular necrosis, as seen in Figure 1d. The control plants remained entirely free from disease symptoms. The procedure for re-isolating the pathogen from the affected leaf tissue was followed, as previously described. The isolates demonstrated a morphology identical to that of the pure cultures stemming from field-diseased leaves. Following a standardized protocol, the pathogenicity test was performed in duplicate. Based on our review of existing literature, this is the first documented case of A. alternata acting as the causative agent for leaf spot disease affecting broccoli plants in Ecuador. Strategies to address this pathogenic threat are developed through the act of diagnosing the disease. A deeper look into biological and chemical methods, or the creation of resistant broccoli varieties, is needed for effective control of this broccoli pathogen.

Eye ailments are treated with Eriocaulon buergerianum, a traditional Chinese medicinal herb. The geographical coordinates 120°19’E, 27°58’N marked the location in Yongjia county, Zhejiang province, China, where E. buergerianuim suffered a severe brown spot disease in July 2020. From the survey of around 150 plants, seventy-three displayed the presence of brown leaf spots. Concentrated on the leaves were yellowish-brown to brown spots. The disease’s progression exhibited the spots’ expansion and subsequent fusion. Wilting was observed in sixty of the one hundred and fifty plants (Figure 1, panels A through D). Surface-sterilized diseased tissues in 75% ethanol (30 seconds), then rinsed thrice with sterile distilled water, were air-dried (5 minutes) before placement on potato dextrose agar (PDA) maintained at 26°C under a 12-hour light/dark cycle for a 4-day culture period. Five isolates, originating from the hyphal tip technique, were maintained on malt extract agar (MEA), oatmeal agar (OA), and PDA. Following seven days of growth at 26 degrees Celsius, the colonies exhibited light yellowish-brown cores encircled by gray-white rims; the reverse surfaces displayed reddish- to yellowish-brown cores. Upon reaching seven days old, colonies cultivated on oatmeal agar (OA) presented a meager aerial mycelium, characterized by central yellowish-brown areas and a complementary light yellowish-brown hue on their reverse surfaces. PDA-grown colonies, seven days old, displayed yellowish-brown, floccose, aerial mycelia characterized by a reddish-brown to yellowish-brown pigment on the underside (Figure 1E-G). The colonies’ ability to produce microsclerotia was evident on OA and PDA media. The sole fungal structures generated on carnation leaf agar and water agar were macroconidia. The macroconidiophores consisted of a stipe supporting penicillate, fertile branches, culminating in a clavate vesicle. Hyaline, colorless, 1 to 2 septate macroconidia, predominantly one septum, were cylindrical and rounded at both ends. Their lengths measured 7186 to 9611 micrometers (mean = 8227 micrometers, n = 50), and their widths spanned 413 to 521 micrometers (mean = 463 micrometers, n = 50) (Figure 1H-K). On CLA or WA medium, the isolate exhibited morphological characteristics that paralleled those of the Calonectria petridis species complex, supporting the conclusions of Alfenas et al. (2015) and Liu et al. (2020). A sequencing analysis was conducted on the genes associated with actin (Act), calmodulin (Cal), internal transcribed spacer (ITS), Histone3 (His3), a fragment of the large subunit nuclear ribosomal DNA (LSU), RNA polymerase II subunit 2 (Rpb2), translation elongation factor 1 (Tef1), and -tubulin 2 (Tub2). The following entries were submitted to GenBank: His3 (Not detected); Act, OM933603, MZ770831, OM933604 to OM933606; Cal, OM933607, MZ770832, OM933608 to OM933610; ITS, OM955624, MZ720794, OM955625 to OM955627; LSU, OM955640, MZ720792, OM955641 to OM955643; Rpb2, OM933615, MZ770834, OM933616 to OM933618; Tef1, OM933611, MZ770833, OM933612 to OM933614; and Tub2, OM933619, MZ770835, OM933620 to OM933622. The genetic makeup of these strains, as reflected in their Act, Cal, ITS, LSU, Rpb2, and Tef1 gene sequences, corresponds to a 99% match with the ex-type strain Ca. pteridis CBS111793. Pseudopteridis CBS16328, characterized by sequences Act (GQ280494, MT335112), Cal (GQ267413, MT335347), ITS (GQ280616, MT359808), LSU (GQ280738, MT359568), Rpb2 (KY653438, MT412640), and Tef1 (FJ918563, MT412878), represents a unique specimen. The Tub2 sequences demonstrated a 99% similarity to the sequences of the former holotype Ca. pteridis CBS111793 (Tub2, DQ190578), as previously reported by Alfenas et al. (2015), Liu et al. (2020), and Lombard et al. (2016). Phylogenetic investigations showed a correlation between these strains and Ca. Figure 2 illustrates a clade containing Pseudopteridis CBS16328, which exhibited a high bootstrap value of 85. In August of 2020, healthy E. buergerianum plants, showing signs of bloom and fruiting, were used to determine the pathogenicity of the isolated strains. The mycelium from isolate GJC3 was cultured on CLA medium, maintained at 26 degrees Celsius under a 12-hour light/dark cycle, over a period of ten days. An inoculation procedure, involving spraying eight healthy plants with a conidial suspension (10 mL of 1×10⁵ conidia/mL), was carried out. Eight additional plants were sprayed with a control treatment: 10 mL of sterilized water. The experiment was repeated in a series of three trials. Greenhouse pathogenicity tests were conducted under controlled conditions (60% relative humidity, 28-20°C day/night temperature fluctuation, and natural sunlight). Fifteen days after inoculation, visual assessment revealed yellowish-brown to brown spots and leaf withering on the inoculated plants, while the control plants displayed no such signs of disease (Figure 1, panels L-N). The inoculated plants produced a re-isolation of Ca. pseudopteridis, its morphology and genetic sequence aligning with the initial GJC3 isolate. Ca. pseudopteridis was absent in the control plant samples. These organisms were identified as Ca. by examining their morphological traits, molecular profiles, and pathogenic properties. jak signals Pseudopteridis: a plant genus with a captivating history. This report’s findings provide a basis for additional inquiries into the biology and management approaches for this disease.

A popular fruit across Korea, Japan, and China is the Oriental melon (Cucumis melo L.), as detailed in Shin et al. (2017). Fruit specimens, collected in April 2022 from Sangju, Gyeongbuk Province, Korea (36°27′54.6″N, 128°10′49.7″E), exhibited an approximate 5% disease prevalence with a severity level between 10% and 15%. The initial indicators involved a contraction of the surface, an over-absorption of liquids, a loss of structure, a change to a darker color, and a creation of sunken areas. From within, the flesh deteriorated, transforming from brown to black, and growing into dark masses of fungi. Upon isolation, fungal strains OM-rot-01 and OM-rot-02 exhibited comparable cultural characteristics. Within seven days of incubation at 25°C, flat, pale grey to olivaceous aerial mycelium grew on potato dextrose agar (PDA), malt extract agar (MEA), and oatmeal agar (OA). A subsequent abundance of buff-colored pycnidial ascomata formed exclusively on oatmeal agar. Cylindrical to clavate asci, bitunicate, were 484–690 µm long and 61–69 µm wide (n=10). Ascospores were biseriate, sparse, ellipsoidal, straight to slightly curved, hyaline, smooth, 1-septate, with obtuse apices, measuring 111–149 µm long and 38–54 µm wide (n=20).