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Greenhouse evaluations were conducted also to evaluate the efficacy of boscalid, fluopyram, solatenol, and adepidyn on A. solani isolates possessing individual SDH mutations. Additionally, field trials were conducted to determine the effects application of these SDHI fungicides on the frequency of SDH mutations. Fluopyram, solatenol, and adepidyn had high intrinsic activity against A. solani when compared to boscalid, based on in vitro assays. The application of adepidyn and solatenol resulted in greater early blight control than the application of boscalid and fluopyram in greenhouse experiments. Molecular characterization of A. solani isolates collected from the field trials determined that the frequency of the H134R-mutation can increase in response to more recently developed SDHI fungicides. buy Decitabine In contrast, the H278R/Y- and H133R-mutations decreased to the point of being nearly absent in these field experiments.Maize (Zea mays L.) is the most widely grown crop in China, which was planted 41.28 million hectares in 2019 (http//data.stats.gov.cnw/easyquery.htm?cn=C01&zb=A0D0F&sj=2019). Several fungal diseases of maize are reported in which stalk rot has become one of the most destructive diseases in China. The average yield losses affected by the disease are estimated at 10% to 20% (Yu et al. 2016). From 2017 to 2019, a survey was conducted to determine the population diversity of Fusarium species associated with maize diseases in 18 cities across Henan province. Fusarium stalk rot of maize with disease incidence more than 25% was observed in two continuous maize fields at Xuchang city. The diseased stem tissues from junctions in health and disease were chopped into small pieces (3 × 8 mm), superficially disinfected (70% ethyl alcohol for 1 min), placed onto potato dextrose agar (PDA) amended with L-(+)-Lactic-acid (1 g/L), poured in petri plates and incubated at 25°C for 4 days. Mycelia showing morphological characterof maize stalk rot in Pakistan (Tahir et al. 2018). To our knowledge, this is the first report of F. thapsinum associated with maize stalk rot in China. The discovery will strengthen the theoretical foundation of maize stalk rot disease management.A maize-infecting polerovirus, variously named maize yellow dwarf virus RMV2 (MYDV RMV2), MYDV-like, and maize yellow mosaic virus (MaYMV), is frequently found in mixed infections in plants also infected with maize chlorotic mottle virus (MCMV) and sugarcane mosaic virus (SCMV), known to synergistically cause maize lethal necrosis (MLN). MaYMV was discovered in deep sequencing studies precipitated by recent maize lethal necrosis (MLN) emergence and is prevalent at global locations with MLN, but its role in or contribution to disease was not known. We examined how MaYMV impacted disease development in mixed infections with MCMV, SCMV, and both MCMV and SCMV compared to mock inoculated plants. Results demonstrated that MaYMV symptoms included stunting as well as leaf reddening in single and mixed infections. MaYMV did not recapitulate MLN synergistic disease in double infections in which either MCMV or SCMV was missing (MaYMV + MCMV or MaYMV + SCMV), but did significantly enhance stunting in mixed infections, and suppressed titers of both MCMV and SCMV in double infections. Interestingly, MaYMV strongly suppressed the SCMV-induced titer increase of MCMV in triple infections, but MLN symptoms still occurred with the reduced MCMV titer. These data indicate the potential disease impact of this newly discovered ubiquitous maize virus, alone and in the context of MLN.Phytophthora blight is a destructive disease caused by the oomycete Phytophthora capsici which affects vegetable production throughout the state of Tennessee and worldwide. Fungicides are a primary control method used in managing Phytophthora blight, but in some cases efficacy of these products has been reduced or lost in the field. In 2018 and 2019, efficacy of six fungicides was tested in vitro on 184 P. capsici isolates collected in TN using radial growth assays. The fungicides included in the study were mefenoxam, fluopicolide, oxathiapiprolin, dimethomorph, mandipropamid, and cyazofamid. Seven isolates were resistant to mefenoxam, 86 were resistant to fluopicolide, one was resistant to oxathiapiprolin, and 13 were resistant to cyazofamid. None were resistant to dimethomorph or mandipropamid. Of the 86 isolates resistant to fluopicolide, five were also resistant to mefenoxam. Resistance to fluopicolide and cyazofamid was widespread in TN, while it was more localized for mefenoxam and oxathiapiprolin. The results of this study show that fungicide resistance is widespread in P. capsici in TN, and implications for Phytophthora blight management are discussed.Watermelon (Citrullus lanatus T.) is one of the most important economic crops in China. Soil-borne diseases are becoming more and more serious with longer growing seasons and continuous cropping of watermelon in greenhouses. In May 2020, symptoms were observed on plants in greenhouses located at Xingtai, Hebei province of China and included wilted leaves, chlorosis and plant death. Among the 26 greenhouses examined, symptomatic plants were observed in 17 greenhouses. The incidences of infected plants ranged from 1% to 35%, and caused an average 10% yield loss. Symptoms began on lower part of the plants and progressed upward to the vines and leaves. At the early stage of infection, the edge of watermelon leaves changed from green to yellow, and became soft. As the disease progressed, infected leaves wilted and desicated. The vascular tissue of the stem exhibited a uniform brown discoloration that often extended throughout the vine. To identify the causal agent, small pieces approximate 3.0×3.0 mm size of infecmal RNA Genes for Phylogenetics. PCR protocols a guide to methods and applications, 18(1), 315-322. Bellemain, E., et al. 2010. ITS as an Environmental DNA Barcode for Fungi an in Silico Approach Reveals Potential PCR Biases. BMC microbiology, 10(1), 1-9. Liu, Y. J., et al. 1999. Phylogenetic Relationships Among Ascomycetes Evidence from an RNA Polymerse II SubunitMol. Biol. Evol. 161799-1808.