First Report of Anthracnose Caused by Colletotrichum gloeosporioides on Cinnamomum camphora in Korea.

Cinnamomum camphora, known as the camphor tree, is an evergreen tree widely cultivated in Asia as an ornamental plant (Singh and Jawaid, 2012). In June 2023, several leaves on a total of 10 trees planted on a street in Suncheon, Jeonnam Province, Korea showed black spots. Disease incidence was observed in at least 15% of the 10 trees. The symptoms included circular spots with a light ash-colored center and dark brown borders. The size of lesions varied depending on the progress of the disease. The disease progressed by 30% on the tree leaves. To isolate the pathogen, we cut out the lesions on the leaf surface sterilized with 70% ethanol for one minute, washed three times with sterilized distilled water, dried, and placed on water agar. Then, it was incubated at 25°C for three days. Emerging hyphae from the samples were subcultured on potato dextrose agar (PDA), resulting in three independent isolates (SYP-F1226-1 to SYP-F1226-3) after single spore isolation from 3 independent trees. The isolates exhibited grayish fluffy mycelium in the center of the colony, while the edges were white on PDA. Conidia had rounded cylindrical shape and were 4.9 to 8.4 µm  1.4 to 3.1 µm (avg. 5.9  2.1 µm, n = 100) in size. Appressoria were round, dark gray, produced at the tip of the germ tube after a septum formed the conidium. The morphological characteristics matched those of Colletotrichum species complexes. (Damm et al., 2012; Weir et al., 2012). For molecular identification, ITS (OR647338 to 40), GAPDH (OR657042 to 44), CHS-1 (OR657045 to 47), ACT (OR657048 to 50), and CAL (OR657051 to 53) sequences from isolates SYP-F1226-1~3 showed a 99.65%, 98.56%, 99.00%, 99.28%, and 99.52% identity with that of type strain C. gloeosporioides ICMP 17821 (JX010152, JX010056, JX009818, JX009531, and JX010445, respectively). Using the MEGA X program (Kumar et al. 2018), maximum likelihood analysis based on the concatenated sequences placed the isolates within a clade comprising C. gloeosporioides. Pathogenicity of SYP-F1226-1 was tested using three leaves from a 1-year-old branch of three independent healthy C. camphora plants. The leaf surfaces were sterilized by rubbing a cotton pad soaked in 70% ethanol and then wiping them with a sterilized cotton pad. The leaves per plant were inoculated with 5 mL of a conidial suspension (1 × 105 conidia/mL), both with and without wounding. Another three control leaves were inoculated with sterile distilled water, both with and without wounding. The inoculated leaves were wrapped in a plastic bag for 48 hours under conditions of 100% relative humidity. Spot symptoms were observed on both wounded and non-wounded leaves 21 days after inoculation. No symptoms were observed in the control on either of the wounded leaves. Pathogenicity tests were performed three times. The pathogen was re-isolated from the lesion after treatment, and its identity was confirmed using the five genes and morphological characteristics. This confirms the fulfillment of Koch's postulates. C. fioriniae (Liu et al, 2022) and C. siamens (Liu et al, 2022; Khoo et al, 2023) have been reported as the causal pathogen of anthracnose in C. camphora, but C. gloeosporioides has not been reported as a pathogen in C. camphora. To our knowledge, this is the first report of anthracnose caused by C. gloeosporioides on C. camphora in Korea. This study will provide symptomatic, mycological, and molecular biological information for the early detection of anthracnose disease in C. camphora plants.

Agrobacterium tumefaciens-Mediated Transformation of the Aquatic Fungus Phialemonium inflatum FBCC-F1546.

Phialemonium inflatum is a useful fungus known for its ability to mineralise lignin during primary metabolism and decompose polycyclic aromatic hydrocarbons (PAHs). However, no functional genetic analysis techniques have been developed yet for this fungus, specifically in terms of transformation. In this study, we applied an Agrobacterium tumefaciens-mediated transformation (ATMT) system to P. inflatum for a functional gene analysis. We generated 3689 transformants using the binary vector pSK1044, which carried either the hygromycin B phosphotransferase (hph) gene or the enhanced green fluorescent protein (eGFP) gene to label the transformants. A Southern blot analysis showed that the probability of a single copy of T-DNA insertion was approximately 50% when the co-cultivation of fungal spores and Agrobacterium tumefaciens cells was performed at 24-36 h, whereas at 48 h, it was approximately 35.5%. Therefore, when performing gene knockout using the ATMT system, the co-cultivation time was reduced to ≤36 h. The resulting transformants were mitotically stable, and a PCR analysis confirmed the genes' integration into the transformant genome. Additionally, hph and eGFP gene expressions were confirmed via PCR amplification and fluorescence microscopy. This optimised transformation system will enable functional gene analyses to study genes of interest in P. inflatum.

Genome sequence of freshwater sediment isolated fungus Westerdykella aurantiaca strain NNIBRFG27121.

We sequenced the genome of Westerdykella aurantiaca NNIBRFG27121 strain isolated from the wetland of Maehwamarum Habitat in Korea. The final assembly consisted of six scaffolds with a size of 31.96 Mb and an N50 of 8,770,400 bp. This genome will help in comparing species within the Westerdykella genus.

Assessing the behavior of the feed-water constituents of a pilot-scale 1000-cell-pair reverse electrodialysis with seawater and municipal wastewater effluent.

Reverse electrodialysis (RED) has vast potential as a clean, nonpolluting, and sustainable renewable energy source; however, pilot-scale RED studies employing real waters remain rare. This study reports the largest RED (1000 cell pairs, 250 m2) with municipal wastewater effluent (1.3-5.7 mS/cm) and seawater (52.9-53.8 mS/cm) as feed solutions. The RED stack was operated at a velocity of 1.5 cm/s and the pilot plant produced 95.8 W of power (0.38 W/m2total membrane or 0.76 W/m2cell pair). During operation of the RED, the inlet design of the stack, comprising thin spacers, and the water dissociation reaction at the cathode were revealed as vulnerabilities of the stack. Specifically, pressure drops at the fluid inlet parts had the most detrimental effects on power output due to clogged spacers around the inlet parts. In addition, precipitates resulting in inorganic fouling were inevitable during the water dissociation reaction due to significant potential generated by the stack in the cathode chamber. Na+ and Cl- accounted for the majority of ions transferred from seawater to wastewater effluent through ion exchange membranes (IEMs). Moreover, some divalent cations in seawater, Mg2+ and Ca2+, were also transferred to the wastewater effluent. Some organics with relatively low molecular weights in the wastewater effluent passed through the IEMs, and their hydrophobic properties elevated the specific UV absorbance (SUVA) level in the seawater.