First Report of Botrytis cinerea Causing Gray Mold on Tea (Camellia sinensis) in China.

Tea (Camellia sinensis (L.) O. Kuntze) is an important economic crop cultivated in China. In March 2019, leaf blight symptoms were observed on tea trees (C. sinensis cv. Fuding-dabaicha) in Enshi City (30º02'66" S, 109º01'56" W), Hubei Province (Fig. 1A). The disease occurred on the senescent flowers and mature leaves. The average disease incidence was approximately 10% of plants in the surveyed 30 ha tea garden. Initial symptoms consisted of brown lesions, which expanded and became covered with gray mold, followed by abscission. To identify the pathogen, 20 symptomatic leaves were collected and 0.5 cm2 diseased leaf pieces were excised and surface sterilized by immersion in 1.5% sodium hypochlorite (NaOCl) for 2 min, and rinsed three times in sterilized distilled water. The leaf pieces were allowed to dry, placed on potato dextrose agar (PDA) plates, and incubated at 20°C under 12h fluorescent light. The fungus formed gray to grayish brown colonies (Fig. 1B) and produced conidia after 1 week. The isolate was purified by single spore isolation. The conidia were one-celled, ellipsoid or ovoid, almost colorless, with a size range of 5.3 to 10.24 × 5.2 to 8.1 µm (n = 50) (Fig. 1C). The sclerotia produced in culture were black, round or irregular in shape and 1.3 to 2.2 × 2.0 to 3.3 mm (average 1.8 × 2.3 mm) in size. Morphological characteristics of these isolates matched the description of Botrytis spp. (Hong et al. 2001). Representative isolate LCHM was selected for molecular identification based on DNA sequencing of the ITS region of rDNA and three nuclear protein-coding genes (G3PDH, HSP60 and RPB2) (Staats et al. 2005). BLAST analysis showed that isolate LCHM (GenBank Acc. Nos. MN448502, MN448500, MN433708 and MN448501 for ITS, G3PDH, HSP60 and RPB2, respectively) shared 99 to 100% identity with B. cinerea (GenBank Acc. Nos. MH316147.1, MG846500.1, MG846504.1 and MG846510.1, respectively), which suggested that isolate LCHM belongs to B. cinerea. This identification was further confirmed by phylogenetic analysis based on combined DNA sequence data of G3PDH, HSP60 and RPB2 (Fig. 2). For the pathogenicity test, needle-wounded, attached leaves on 1-year-old C. sinensis cv. Fuding-dabaicha plants were inoculated with mycelial plugs (6 mm diameter from 2-day-old PDA cultures) or a conidial suspension (20 µL, 1×106 conidia/ml in half strength potato dextrose broth) of isolate LCHM on three plants per treatment (six leaves). The control treatments were also wounded, but only treated with agar plugs or half strength PDB. All inoculated plants and controls were incubated in a growth chamber (20°C, 90 ± 10% RH). Leaves inoculated with mycelial plugs, whether wounded or not, showed brown necrotic lesions around the agar plugs after 2 days (Fig. 1D, E), whereas conidial inoculations of wound sites showed necrotic lesions after 6 days (Fig. 1 F, G). Non-wounded leaves inoculated with conidia and all the control treatments remained symptomless. B. cinerea was reisolated from the inoculated leaves and isolates were morphologically similar to the original cultures. Gray mold of C. sinensis caused by B. cinerea has been recorded in Japan, Turkey, and Brazil (Hamaya 1981, Aziz and Harun 2010, Pereira and Mio, 2020). To our knowledge, this is the first report of gray mold caused by B. cinerea on C. sinensis in China. B. cinerea may cause economic losses of tea, therefore, more surveys in other tea-growing regions should be done to specifically search for this disease.

The Genome Sequence of Alcaligenes faecalis NBIB-017 Contains Genes with Potentially High Activities against Erwinia carotovora.

Alcaligenes faecalisNBIB-017, a Gram-negative bacterium, was isolated from soil in China. Here, we provide the complete genome sequence of this bacterium, which possesses a high number of genes encoding antibacterial factors, including proteins and small molecular peptides.

Development of a method for automated and stable myocardial perfusion measurement using coronary X-ray angiography images.

The purpose of this study was to develop a method for automatic and stable determination of the optimal time range for fitting with a Patlak plot model in order to measure myocardial perfusion using coronary X-ray angiography images. A conventional two-compartment model is used to measure perfusion, and the slope of the Patlak plot is calculated to obtain a perfusion image. The model holds for only a few seconds while the contrast agent flows from artery to myocardium. Therefore, a specific time range should be determined for fitting with the model. To determine this time range, automation is needed for routine examinations. The optimal time range was determined to minimize the standard error between data points and their least-squares regression straight line in the Patlak plot. A total of 28 datasets were tested in seven porcine models. The new method successfully detected the time range when contrast agent flowed from artery to myocardium. The mean cross correlation in the linear regression analysis (R(2)) was 0.996 ± 0.004. The mean length of the optimal time range was 3.61 ± 1.29 frames (2.18 ± 1.40 s). This newly developed method can automatically determine the optimal time range for fitting with the model.

Draft Genome Sequence of Bacillus thuringiensis NBIN-866 with High Nematocidal Activity.

Bacillus thuringiensis NBIN-866, a Gram-positive bacterium, was isolated from soil in China. We announce here the draft genome sequence of strain B. thuringiensis NBIN-866, which possesses highly nematocidal factors, such as proteins and small molecular peptides.

Development of a theory for generating regional cardiac perfusion images during coronary angiography in the coronary angiography lab.

The purpose of this study was to develop a novel theory and method for generating regional myocardial perfusion images using fluoroscopy in the coronary angiography lab. We modified the Kety model to introduce the Patlak plot method for two-dimensional fluoroperfusion (FP) imaging. For evaluation, seven porcine models of myocardial ischemia with stenosis in the left coronary artery were prepared. Rest and stress FP imaging were performed using cardiovascular X-ray imaging equipment during the injection of iopamidol via the left main coronary artery. Images were acquired and retrospectively ECG gated at 80 % of the R-R interval. FP myocardial blood flow (MBF) was obtained using the Patlak plot method applied to time-intensity curve data of the proximal artery and myocardium. The results were compared to microsphere MBF measurements. Time-intensity curves were also used to generate color-coded FP maps. There was a moderate linear correlation between the calculated FP MBF and the microsphere MBF (y = 0.9758x + 0.5368, R² = 0.61). The color-coded FP maps were moderately correlated with the regional distribution of flow. This novel method of first-pass contrast-enhanced two-dimensional fluoroscopic imaging can quantify MBF and provide color coded FP maps representing regional myocardial perfusion.