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Dandong has become the largest strawberry production and export base in China. Strawberry black spot disease is widespread and causes significant economic losses to strawberry growers in both the growing and harvest seasons. Until now, no study has reported the presence of the Alternaria species, the pathogen of strawberry black spot disease, in Dandong, Liaoning province, China. In 2020–2022, 108 isolates were obtained from strawberry leaves with typical symptoms of strawberry black spot disease from 56 major professional growing operations. Combined with morphological and molecular characteristics, the majority of isolates were identified as A. tenuissima (78 isolates, 72.2%), which had established total supremacy, followed by A. alternata (30 isolates, 27.8%). The pathogenicity results show that A. tenuissima and A. alternata are the two main pathogenic factors of strawberry black spot disease, the disease indexes of which were designated as 49.6–100.0% and 20.4–59.5%. To our knowledge, this paper is the first to identify A. tenuissima and A. alternata as causing black spot disease in strawberries in Dandong, China. [ABSTRACT FROM AUTHOR]

In the present study, a novel double-stranded RNA (dsRNA) mycovirus designated as "Alternaria tenuissima partitivirus 2" (AttPV2), was isolated from Alternaria tenuissima strain BJ-SY-1, a phytopathogenic fungus causing muskmelon leaf blight in Beijing municipality of China. The genome of AttPV2 comprises two dsRNA segments. The larger segment is 1829 bp in length and has a single open reading frame (ORF), potentially encoding a 65.8-kDa RNA-dependent RNA polymerase (RdRp), and the smaller segment is 1681 bp in length and also contains a single ORF, encoding a putative coat protein (CP) with a molecular mass of 56.0 kDa. BLASTp analysis revealed that the RdRp and CP encoded by the two ORFs of AttPV2 have the highest sequence identity, 85.9% and 75.0%, respectively, to their counterparts in Colletotrichum eremochloae partitivirus 1 (CePV1). Phylogenetic analysis based on RdRp sequences showed that AttPV2 clustered most closely with CePV1, a member of the proposed genus "Epsilonpartitivirus" in the family Partitiviridae. Hence, we propose that AttPV2 is a new epsilonpartitivirus from A. tenuissima. To the best of our knowledge, this is the first report of an epsilonpartitivirus infecting A. tenuissima. [ABSTRACT FROM AUTHOR]

The complete genome sequence of a double-stranded RNA (dsRNA) mycovirus that was isolated from Alternaria solani strain DT-10 causing potato foliar disease was determined. The virus, designated as "Alternaria solani chrysovirus 1" (AsCV1), has four dsRNA segments (dsRNA 1-4) with a length of 3600 bp, 3128 bp, 2996 bp, and 2714 bp, respectively. The RNA-dependent RNA polymerase (RdRp, 1084 amino acids [aa]), putative capsid protein (905 aa), alphachryso-P3 (835 aa), and alphachryso-P4 (729 aa) were encoded by dsRNA1, dsRNA2, dsRNA3, and dsRNA4, respectively, which had the highest sequence identity of 41.77%-72.38% to their counterparts in Helminthosporium victoriae virus 145S (HvV145S) of the genus Alphachrysovirus, family Chrysoviridae. Moreover, the 5′-untranslated regions (UTRs) of AsCV1 dsRNA 1-4, which contained several unique inserts (3-37 bp) and deletions (5-64 bp), shared 51.65%-68.01% identity with those of HvV145S. Phylogenetic analysis based on RdRp sequences showed that AsCV1 clustered the most closely with HvV145S. Considering its distinct host specificity, the low sequence similarity of its encoded proteins to those of other viruses, the unusual features of the 5′-UTRs of its dsRNA 1-4, and the phylogenetic position of its RdRp gene, AsCV1 should be considered a member of a new species in the genus Alphachrysovirus. To the best of our knowledge, this is the first alphachrysovirus identified from phytopathogenic A. solani. [ABSTRACT FROM AUTHOR]

The anastomosis groups (AGs) of Rhizoctonia causing banded leaf and sheath blight (BLSB) on maize in the Shanxi province of China were identified. In total, 147 isolates of Ceratobasidium (2) and Rhizoctonia (145) were collected in 2017–2018 from maize sheaths in Shanxi province with symptoms of BLSB. Based on the number of nuclei, presence of hyphal anastomosis, and sequence analysis of ITS rDNA, 76 isolates (51.70%) were identified as belonging to Rhizoctonia solani AG-5, 38 (25.85%) as Rhizoctonia zeae (WAG-Z), 20 (13.61%) as Rhizoctonia solani AG-1-IA, 5 (3.40%) as R. solani AG-1-IB, 4 (2.72%) as R. solani AG-4-HGIII, 2 (1.36%) as R. solani AG-4-HGI, and 2 (1.36%) as Ceratobasidium sp. AG-K. All of the Rhizoctonia isolates produced symptoms of BLSB on maize seedlings with the disease incidence 45.16-93.33% and the disease index 15.32-55.00. Rhizoctonia solani AG-5 was the most common AG group causing BLSB in Shanxi province of China. To our knowledge, this is the first report on anastomosis groups of Rhizoctonia causing BLSB in Shanxi province of China. [ABSTRACT FROM AUTHOR]

As a devastating disease, leaf spot of Chinese cabbage (Brassica rapa subsp. pekinensis) caused by Alternaria could render the edible leaves unusable and lead to yield loss. Till now, no research related to Alternaria species causing leaf spot on Chinese cabbage was recorded in the Shanxi province of China. In the current study, 246 Alternaria isolates were recovered from diseased leaves of Chinese cabbage with the symptoms of leaf spot and identified based on morphological traits and phylogenetic analysis of the sequences of the internal transcribed spacer regions of ribosomal DNA (rDNA ITS) and the partial coding sequence of the histone 3 gene. These isolates were grouped into four Alternaria species, of which A. tenuissima was predominant (175 isolates, 71.2%), followed by A. alternata (67 isolates, 27.2%), A. brassicicola (three isolates, 1.2%), and A. solani (one isolate, 0.4%). All the tested Alternaria isolates were pathogenic to detached leaves of Chinese cabbage with the disease incidence and disease index ranging from 73.3% to 100.0% and 20.8 to 99.1, respectively. To our knowledge, it is the first comprehensive study of Alternaria species inciting leaf spot on Chinese cabbage in Shanxi province of China; also, this is the first report of A. tenuissima, A. alternata, and A. solani infecting Chinese cabbage in Shanxi province of China. This study provides important information on the Alternaria species associated with leaf spot of Chinese cabbage, which can help design the strategies for managing Alternaria leaf spot disease on Chinese cabbage. [ABSTRACT FROM AUTHOR]

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A new double-stranded RNA (dsRNA) virus named Alternaria alternata botybirnavirus 1 (AaBRV1) was isolated from Alternaria alternata strain SD-BZF-19, a phytopathogenic fungus infecting watermelon in China. The genome of AaBRV1 consists of two dsRNA segments (dsRNAs 1 and 2), 6,130 and 5,862 bp in size, respectively. The sequence contains two putative open reading frames (ORFs) which encode two polyproteins of 1,874 and 1,784 amino acids, respectively. Nucleotide sequence comparisons revealed that the two ORFs of AaBRV1 have the highest similarity 60.3% and 56.7%, respectively, with dsRNAs 1 and 2 of Botrytis porri RNA virus 1 (BpRV1). The two polyproteins encoded by dsRNA1 and dsRNA2 shared the highest amino acid identities with the cap-pol fusion protein (60.2%) and hypothetical protein (53.7%) of BpRV1, respectively. AaBRV1 is composed of isometric particles, approximately 35 nm in diameter. Phylogenetic analysis of the RNA dependent RNA polymerase (RdRp) domain of the polyprotein revealed that AaBRV1 clusters together with members of the genus Botybirnavirus. These findings support the discovery of a new botybirnavirus in A. alternata. [ABSTRACT FROM AUTHOR]

• Virtual power dispatching unit (VPDU) composed of fixed-frequency air conditioner and ES. • Reduce the impact on user comfort through adjustable capacity constraints on VPDUs. • Not only peak clipping, but also valley filling if necessary. • Control loop ensures fast and accurate response of VPDU. In recent years, with the improvement of residents' living standards, the number of air-conditioning installations has increased. Large-scale decentralized air-conditioning load is one of the main causes of power grid peaks and valleys. Among them, more than half of residential air conditioners (ACs) are fixed-frequency air conditioners in China. How to effectively make them participate in the power dispatching of the power grid has become the focus of research. This article first introduces the principle of the electric spring (ES), sets up a virtual power dispatching unit (VPDU) based on ES and fixed-frequency air conditioner, and explains its working mode. Then propose a layered power scheduling strategy. The scheduling layer formulates the day-ahead dispatching plan based on the power demand and the load aggregator (LA) bidding information to minimize costs; the LA layer integrates the information to make a day-ahead bidding and allocate power adjustment instructions; The terminal layer designs the response strategy for a single dispatching unit. Finally, an example analysis and simulation experiments are used to illustrate the application method of the proposed scheduling strategy and verify its effectiveness. [ABSTRACT FROM AUTHOR]

• A novel strain of Alternaria alternata chrysovirus 1 (AaCV1) from A. tenuissima SD-BZF-12 was designated as AaCV1-AT1. • It was the first chrysovirus infecting A. tenuissima. • AaCV1-AT1 can reduce colony growth rate and spore production ability of its host fungus. • AaCV1-AT1 can increase the median effective concentration of difenoconazole or tebuconazole on its host. The leaf blight caused by the genus Alternaria is one of the most epidemic diseases on watermelon, and A. tenuissima is the dominant pathogenic species in China. Mycoviruses are found ubiquitously in filamentous fungi, and an increasing number of novel mycoviruses infecting the genus Alternaria have been reported. In this study, a mycovirus from A. tenuissima strain SD-BZF-12 was identified and characterized, whose genome size was very similar with Alternaria alternata chrysovirus 1-N18 (AaCV1-N18). The dsRNA1- and dsRNA2-encoded proteins of the virus had 99 % identities with counterparts of AaCV1-N18; and the dsRNA3- and dsRNA4-encoded proteins of the virus showed the 80 % and 94 % sequence identities with proteins deduced from dsRNA4 and dsRNA3 of AaCV1-N18, respectively. Intriguingly, dsRNA5 of the virus encoded a truncated protein with 68 amino acids (aa) by comparing with 115 aa of AaCV1-N18 dsRNA5. Phylogenetic analysis of RNA-dependent RNA polymerase domain suggested that the virus clustered together with AaCV1-N18. Based on these characteristics, the mycovirus was identified to be a novel strain of AaCV1 and designated as AaCV1-AT1. In addition, no obvious differences were observed on colony morphology between AaCV1-AT1-infected and virus-cured strains of A. tenuissima ; however, AaCV1-AT1 infection reduced colony growth rate and spore production ability on host fungus, and increased the median effective concentration of difenoconazole or tebuconazole on its host. This is the first report of AaCV1-AT1 associated with A. tenuissima. [ABSTRACT FROM AUTHOR]

In this study, a new double-stranded RNA (dsRNA) virus, Alternaria tenuissima partitivirus 1 (AttPV1), was isolated from Alternaria tenuissima strain XJ-BZ-2-6, a phytopathogenic fungus infecting cotton in China. The genome of AttPV1 comprised three dsRNAs of 1,785 nt (dsRNA1), 1,545 nt (dsRNA2), and 1,537 nt (dsRNA3) in length, the nucleotide sequence of which was determined using reverse transcription polymerase chain reaction, random-primed clones, and RNA-ligase-mediated rapid amplification of cDNA ends. dsRNA1 had a single open reading frame encoding a putative 61.54-kDa RNA-dependent RNA polymerase (RdRp). dsRNA2 and dsRNA3 were predicted to encode putative coat proteins (CPs) of 47.90 kDa and 46.25 kDa, respectively. The RdRp domain shared 63.54-73.17% amino acid sequence identity with members of the genus Gammapartitivirus. Phylogenetic trees based on RdRp or CP sequences showed that AttPV1 clustered with members of the genus Gammapartitivirus. Hence, these results indicate that AttPV1 is a new gammapartitivirus from A. tenuissima.

Watermelon is an economically important crop in China and is commonly affected by Alternaria -like leaf blight that can result in significant economic losses. In this study, 830 Alternaria isolates, recovered from symptomatic watermelon leaves, were identified based on morphological traits, pathogenicity, and multilocus sequence analyses of glyceraldehyde-3-phosphate dehydrogenase ( GAPDH ), histone 3 ( HIS3 ), the internal transcribed spacer of ribosomal DNA (rDNA ITS), and the RNA polymerase II second largest subunit ( RPB2 ). Watermelon isolates grouped to five Alternaria species and one unclassified Alternaria species. They were A. tenuissima , A. alternata , A. cucumerina , A. infectoria , A. gaisen , and Alternaria sp. Notably, A. tenuissima was the most prevalent (73.5%) of the six isolated species, followed by A. alternata (25.0%), A. cucumerina (1.1%), Alternaria sp. (0.2%), A. infectoria (0.1%), and A. gaisen (0.1%). Pathogenicity tests demonstrated that all six Alternaria species could produce brown necrotic lesions on detached leaves of watermelon. The average disease incidence (75.1%) and average disease index (60.8) of watermelon resulting from inoculation of leaves with A. cucumerina were significantly higher than levels resulting from A. alternata (52.9% and 37.2) and A. tenuissima (47.5% and 30.8). Inoculation with Alternaria sp. resulted in a disease incidence (70.0%) and disease index (51.5), which were lower than those of A. cucumerina . The disease incidence and disease index in watermelon leaves inoculated with the one isolate of A. infectoria and the one isolate of A. gaisen present in the inoculated leaves were 28.9% and 16.4, and 48.9% and 31.4, respectively. Results of the study indicate that Alternaria species associated with watermelon leaf blight in China are more diverse than that has been previously reported. This is the first report globally of A. infectoria , A. gaisen , and an unclassified Alternaria species as causal agents of leaf blight on watermelon.

Influenza vaccine has to be reformulated each year due to the ever-changing antigenicity of the influenza virus. However, few post-licensure studies of influenza vaccine are available in China. We aimed to measure the effectiveness of seasonal influenza vaccine during 2 consecutive seasons. Among children in Guangzhou aged 6 to 59 mo in 2010-2012, we matched each child with clinically diagnosed influenza to 3 healthy children. Cases with clinically diagnosed influenza were identified from surveillance system. Healthy controls were randomly sampled from the Children's Expanded Programmed Immunization Administrative Computerized System. Conditional logistic regression was used to calculate vaccine effectiveness (VE). A total of 275 matched sets of subjects were included. VE levels against clinically diagnosed influenza for both seasons combined was 47.4% [95% confidence interval (CI), 8.5-69.8%] for full vaccination for children aged 6-35 mo, 33.6% (95% CI, 5.4-53.5%) for any vaccination for children aged 6-59 mo, respectively. VE by time since vaccination for any vaccination was 34.6% (95% CI, 4.7-55.2%) in 0-5 mo, and no protection was observed in 6-11 mo. Annual, full and timely vaccination should be encouraged for children.