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979 (Mathur, 1979). To our knowledge, this is the first record of C. capsici causing anthracnose on A. macrorrhizos in China.The fungal genus Alternaria consists of highly diverse species. They can be isolated readily from soil, water, and many plants, and even from animals and humans. Alternaria burnsii is a small-spored species of section Alternaria. It has been reported as a pathogen, an endophyte, and a saprophyte, and can also be found in indoor air. It causes cumin blight, a destructive disease on cumin (Cuminum cyminum), and also causes other serious diseases, such as pumpkin seed rot, date palm leaf spot, wheat leaf spot, and gray spot of Notopterygium incisum. In this study, we sequenced and assembled the first genome of A. burnsii isolate CBS 107.38. The draft genome can be used as a reference for the further study of related pathogens and comparative genomics of Alternaria species.Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat in the world. Chinese wheat landrace ‘Guangtoumai’ (GTM) exhibited a high-level resistance against predominant Pst races in China at the adult-plant stage. The objective of this research was to identify and map the major locus/loci for stripe rust resistance in GTM. A set of 212 recombinant inbred lines (RILs) was developed from a cross between GTM and Avocet S (AvS). The parents and RILs were evaluated in three field tests (2018, 2019, and 2020 at Chongzhou, Sichuan) with the currently predominant Pst races for final disease severity (FDS) and genotyped with the Wheat 55K SNP array to construct a genetic map with 1,031 SNP markers. A major locus, named QYr.GTM-5DL, was detected on chromosome 5DL in GTM. The locus was mapped in a 2.75 cM interval flanked by SNP markers AX-109855976 and AX-109453419, explaining up to 44.4% of the total phenotypic variation. Since no known Yr genes have been reported on chromosome 5DL, QYr.GTM-5DL is very likely a novel adult plant resistance (APR) locus. Haplotype analysis revealed that the resistance allele displayed enhanced levels of stripe rust resistance and is likely present in 5.3% of the 247 surveyed Chinese wheat landraces. The derived cleaved amplified polymorphic sequence (dCAPS) marker dCAPS-5722, converted from a SNP marker tightly linked to QYr.GTM-5DL with 0.3 cM, was validated on a subset of RILs and 48 commercial wheat cultivars developed in Sichuan. The results indicated that QYr.GTM-5DL with its linked dCAPS marker could be used in marker-assisted selection to improve stripe rust resistance in breeding programs, and this QTL will provide new and possibly durable resistance to stripe rust.Geodorum eulophioides Schltr. is a critically endangered orchid listed in the International Union for Conservation of Nature (IUCN) Red List of threatened species. At present, only two natural populations were found in China. It has important scientific and ornamental values because of its uniqueness. During the summer of 2019, a black leaf spot disease occurred on G. eulophioides, in Yachang Orchid National Nature Reserve (E106°13’32″，N24°44’19″) in Guangxi province, China. More than 60% of leaves of these plants were infected. The disease symptoms initially appeared as small yellow circular spots, which enlarged into irregular brown spots (6 to 9 cm length and 3 to 5 cm width). In later stages of the disease development, the center of the spots became dark brown with a clear edge and surrounded by a yellow halo. In severe infections, the spots coalesced covering the entire leaf. Six symptomatic leaves were collected from three infected plants, surface sterilized in 75% ethanol for 15 s and 0.1% HgCl2 for 4 nditions. An equal number of leaves on the same plant were inoculated using sterile PDA plugs and served as mock inoculated controls. After three days, all the inoculated leaves showed black spot symptoms resembling those observed in the field, whereas controls remained symptomless. The fungus was re-isolated from the symptomatic leaves, thus completing Koch’s postulates. check details N. parvum has been reported to cause leaf spot disease on Myristica fragrans (Jayakumar, et al., 2011), Ginkgo biloba (Mirhosseini, et al., 2014), Vitis heyneana (Wu, et al., 2015), and Hevea brasiliensis (Liu et al., 2017), respectively. To the best of our knowledge, this is the first report of N. parvum causing leaf spot disease on G. eulophioides in China. The disease control measures and in-situ conservation method need to be strengthened to protect this rare species.In October 2017, we collected five soil samples from each of several fields with a history of severe corn (Zea mays) seedling disease in Heilongjiang province of China. Affected seedlings were wilted with severe root rot, and a high incidence of seedling death was observed in the fields. Corn seeds were seeded in the collected soil samples and grown in a growth chamber for 21 days set at the following incubation temperatures 21℃/7℃ for 6 days, 10℃/3℃ for 4 days, 16℃/7℃ for 5 days, 20℃/20℃ for 6 days (16 h/8 h, light/dark) (Tang et al. 2019). The corn seedlings in the growth chamber showed the same symptoms observed in the field as mentioned above. Corn root rot samples were collected from several symptomatic plants in the growth chamber to isolate the possible pathogen. Symptomatic roots were washed in 0.5% NaOCl for 2 min, rinsed in sterile water and cut into 1-2 mm segments and then plated on corn meal agar amended with pimaricin (5 μg/ml), ampicillin (250 μg/ml), rifampicin (10 μg/ml), pentachloronitrobenzoil) at a ratio of one petri dish per 100 g soil mix. Ten corn seeds were planted at a depth of 2 cm in a 500-mL pot containing the inoculated soil mix. The control pots were mock inoculated with plain 10% V8 juice agar. Pots were incubated in a greenhouse at temperatures ranging from 21 to 23℃. There were four replications. After 14 days, corn roots brown and rotted were observed, which was similar to those observed in the field and growth chamber. Control plants remained symptomless and healthy. P. torulosum copt was consistently re-isolated from the symptomatic roots. To our knowledge, this is the first report of P. torulosum causing root rot of corn in Northeastern China. Corn is an important crop in Heilongjiang and the occurrence of root rot caused by this pathogen may be a new threat to corn plants. There is a need to develop management measures to control the disease.