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Corn (Zea mays L.) is one of the most important grain crops in the world, especially in China. Besides, corn stalks are often used in production of bio-fuels (Xue et al., 2017). Recently, the production and quality of corn have been severely influenced by corn stalk rot in China caused by Fusarium spp. (Yu et al., 2017). At the end of June of 2019, a field survey of corn was carried out in Tai'an City, western Shandong Province, China. During the survey, the average day time temperature ranged between 22-28°C with intermittent rainfall, the relative humidity was 50-70%. In this survey, the symptomatic corn plants showed signs of necrosis and rotting on stalks and root collars. Five fields were surveyed and symptomatic corn plants were observed in three fields. The incidence rate of disease was about 5%, and the disease was more of a problem in low-lying areas. A total of twenty-eight symptomatic corn plants (7-12 per field), hybrid Denghai-618, at the 3-4 leaf stage were collected and tested for the presence h chamber at 28°C, 60% relative humidity, 16 h / 8 h light regime cycle. Ten days post-inoculation, the inoculated plants showed necrosis, with symptoms of stem rot similar to those observed in the field. The inoculation experiments were repeated twice with the same results, fulfilling Koch's postulates. The root-collars and stems of negative control remained asymptomatic, and P. helicoides was not isolated. Previously, P. helicoides has been reported as a pathogen of strawberry (Zhan et al. 2020) and kiwi fruits (Wang et al. 2015) from China, but not from corn. To our knowledge, it is the first report of P. helicoides causing corn stalk rot in China. In the future, P. helicoides can be considered as a potential candidate causing stem and collar-rot of corn in China, but not the only one. There are other microbes that can produce similar symptoms on corn, and control methods for pathogenic oomycetes differ from those for fungi.Barley (Hordeum vulgare) is a valuable annual cereal crop grown widely throughout the United States and the world. The majority of barley grown commercially in California and throughout the U.S. is used for livestock feed, with the remainder being used by the malting industry and, to a lesser extent, direct food consumption; it is also often employed as a cover crop (Lazicki et al. 2016). Yellow dwarf viruses (YDVs), in the family Luteoviridae, that infect barley and other cereal crops are common and widely distributed throughout California and the U.S. (Griesbach et al. 1989; Seabloom et al. 2009). In April 2018, five barley samples exhibiting typical symptoms of YDV infection (primarily yellowing of leaf margins and tips) collected from fields in Yolo county planted with cultivar Butta 12 , were tested for viruses. Total RNA was extracted from leaf tissue using Trizol reagent, according to the manufacturer's protocol. RNA was used as template in a multiplexed RT-PCR assay designed for the generic detection ctor pJL89 and a BLAST search of the resulting 5621 nucleotide full-length sequence (100% query coverage) once again returned results showing the YDV to be BVG. The full-length sequence was deposited into GenBank (MW853785). Nucleotide sequence comparisons showed that the CA BVG isolate shares 96.62%, 96.57%, and 96.02% identity with the sequences of the BVG-Gimje (KT962089), BVG-Uiseong (LC259081), and BVG-Aus8 (LC500836) isolates, respectively. To our knowledge, this is the first report of barley virus G in California and in the United states. Currently the prevalence, host range and mode and timing of introduction of BVG in California and the U.S. Pterostilbene are unknown; its impact on cereal production and yield in any location in which it has been identified thus far is also unknown and may warrant further investigation.Sacha inchi (Plukenetia volubilis L.) belongs to the family Euphorbiaceae. It is a perennial wooden oilseed crop, and also exhibits a good source of polyunsaturated fatty acids, protein and other bioactive compounds, such as tocopherols, carotenes and phytosterols (Chirinos et al. 2013). During 2017-2018 survey, canker disease showing greyish-brown sunken lesions was observed on the branches of sacha inchi in Danzhou campus, Hainan University, China. The disease incidence is less than 5%. However, it can lead to leaf yellowing, wilt, and eventually the whole plant death. In Nov. 2017, twelve branches showing the typical canker symptoms were collected and covered with parafilm at both ends of all samples to prevent desiccation and placed in black plastic bags keeping at 4°C until isolations were made. Samples were rinsed with tap water and dried with paper towels. Fragments, 5mm in length and cut from the junction of diseased and healthy parts of branches, were surface-sterilized with 2% sodium hypochlorite sodead leaves of P. volubilis in Yunnan Province, China, but did not prove this fungus to be pathogenic (Tennakoon et al. 2016). This is the first report that L. theobromae and L. pseudotheobromae causing stem canker in sacha inchi in Hainan, China. The results pave the way for the development of management strategies for canker disease in sacha inchi.Tabebuia rosea (rosy trumpet) is an economically important Neotropical tree in Mexico that is highly valued for the quality of its wood, which is used for furniture, crafts, and packing, and for its use as an ornamental and shade tree in parks and gardens. During surveys conducted in the lower Balsas River Basin region in the states of Guerrero and Michoacán, symptoms of floral malformation were detected in T. rosea trees. The main objectives of this study were to describe this new disease, to determine its causal agent, and to identify it using DNA sequence data. A second set of objectives was to analyze the phylogenetic relationship of the causal agent to Fusarium associated with Swietenia macrophylla trees with malformation surveyed in the same region, and to compare mycotoxin production and the mating type idiomorphs of fusaria recovered from T. rosea and S. macrophylla. Tabebuia rosea showed malformed inflorescences with multiple, tightly curled shoots, and shortened internodes. A total of 31 Fusarium isolates recovered from symptomatic T.