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Maize sheath rot is a prevalent maize disease in China. From 2020 to 2021, symptomatic samples were collected from the main maize-growing regions of Heilongjiang province. To clarify the population and genetic diversity, as well as the virulence of pathogens responsible for maize sheath rot, a total of 132 Fusarium isolates were obtained and used for follow-up studies. Ten Fusarium species were identified based on morphological characteristics, and phylogenetic analysis was conducted using the TEF-1α gene sequences, including F. verticillioides (50.00%), F. subglutinans (18.94%), the Fusarium incarnatum-equiseti species complex (14.39%), F. temperatum (5.30%), F. acuminatum (3.03%), F. solani (2.27%), F. sporotrichioides (2.27%), F. tricinctum (1.52%), F. asiaticum (1.52%), and F. proliferatum (0.76%). All 10 Fusarium species could produce oval-to-annular lesions on maize sheath, and the lesions were grayish yellow to dark brown in the center and surrounded by a dark gray-to-dark brown halo. Of these, F. tricinctum and F. proliferatum showed significantly higher virulence than the other Fusarium species. In addition, haplotype analysis based on the concatenated sequences of the ITS and TEF-1a genes showed that 99 Fusarium isolates which belonged to the Fusarium fujikuroi species complex—consisting of F. verticillioides isolates, F. subglutinans isolates, F. temperatum isolates, and F. proliferatum isolates—could be grouped into 10 haplotypes, including 5 shared haplotypes (Haps 1, 2, 4, 5, and 6) and 5 private haplotypes (Haps 3, 7, 8, 9, and 10). Furthermore, the F. verticillioides clade in the haplotype network was radial with the center of Hap 2, suggesting that population expansion occurred. This research showed that Fusarium species associated with maize sheath rot in Heilongjiang province are more diverse than previously reported, and this is the first time that F. subglutinans, F. temperatum, F. solani, F. sporotrichioides, F. tricinctum, and F. acuminatum have been confirmed as the causal agents of maize sheath rot in Heilongjiang province. [ABSTRACT FROM AUTHOR]

Morel (Morchella sextelata), a fungus with considerable nutritional, medicinal, and economic value, has been extensively cultivated in China. In May 2023, a rot disease was observed on approximately 20% of the fruiting bodies in a morel greenhouse located in Harbin city, Heilongjiang province, China. In the present investigation, a total of fifteen fungal isolates were obtained, and subsequent analysis confirmed their identification as Penicillium raperi based on morphological and phylogenetic methods. Pathogenicity test provided evidence that P. raperi was capable of inducing rot symptoms which closely resembled those observed in field, thus confirming that P. raperi is the pathogen of M. sextelata. Thereby, this is the first report of P. raperi causing rot disease on M. sextelata worldwide. This study will furnish crucial insights for the management of diseases affecting morel mushrooms in the field. • Rot disease of Morchella sextelata was observed in Heilongjiang province, China. • The pathogen associated with rot disease was identified as Penicillium raperi. • This is the first report of P. raperi causing rot disease on M. sextelata. [ABSTRACT FROM AUTHOR]

The eastern Jilin and Heilongjiang provinces in China are located at the junction between the Paleo-Asian Ocean and Circum-Pacific metallogenic domains, and have been affected by the temporal transition between these domains and their superposition, resulting in intensive and complicated mineralization events. This paper provides a progress in exploration for, and geological research into, endogenic metal deposits and related magmatite in the eastern Jilin and Heilongjiang provinces. Four richly mineralized areas are recognized: (1) the Lesser Xing'an–Zhuangguangcai Range metallogenic belt; (2) the Jiamusi–Khanka metallogenic belt; (3) the Yanbian metallogenic belt; and (4) the Wandashan metallogenic belt. Four temporal peaks in magmatism and metallogenesis are identified: (1) Hercynian orogenic Au deposits (260–250 Ma) show a close relationship with magmatism related to a transitional syn- to post-collisional tectonic setting; (2) Indosinian orthomagmatic ore deposits (230–210 Ma) show a close relationship to mafic–ultramafic magmatism in a post-collision extensional setting; (3) porphyry Mo deposits and skarn deposits of the Late Triassic to the Early Jurassic (200–170 Ma) formed in a continental arc setting, triggered by slab subduction; and (4) late Yanshanian large-scale mineralization was caused by tectonic extension at 133–106 Ma. Yanshanian felsic magmatism shows clear metallogenetic specialization; i.e. each rock type hosts a different type of deposit. [ABSTRACT FROM AUTHOR]

• The Chiweigou gold deposit is redefined as the carbonatite-type deposit. • The ore-forming materials for the calcite veins were came from the mantle. • The deposit were formed in the extension setting related to the oceanic subduction. The Chiweigou gold deposit is located in the eastern Jilin and Heilongjiang provinces at the junction of the Paleo-Asian Ocean and Circum-Pacific metallogenic domains, where was affected by the events that marked the transition between these two domains. The gold orebodies in the Chiweigou deposit are hosted in three calcite veins controlled by compressional-shearing faults, which cut across Early Cretaceous intermediate–acidic volcaniclastic rocks. The Au-bearing calcite veins have low metal sulfide contents (<1%), and the main ore deposits display disseminated, brecciated, comb, and miarolitic structures. The minerals vary from euhedral to anhedral. In addition to the main carriers of the Au and Ag are native gold, calaverite, hessite, and aurotellurite, and the gold-carrying minerals coexist closely with other common minerals in the carbonatite veins such as calcite, quartz, apatite, and magnetite, implying genetic relationships among them. The main type of wall-rock alteration is carbonatization, and alkali metasomatism, including fenitization, is widespread. The SiO 2 contents of the Au-bearing calcite veins show very large variations (0.87–53.9 wt%), and the veins have high contents of CaO (24.4–54.9 wt%) and low contents of MgO (0.06–0.13 wt%) and (Na 2 O + K 2 O) (0.10–0.39 wt%). The main oxide contents show good linear relationships with SiO 2 on Harker diagrams, and this indicates that differentiation took place between the siliceous and carbonate components during the formation of the calcite veins. The LREE contents of the calcite veins are higher than the HREE contents (LREE/HREE ratios range from 10.7 to 15.8), and the normalized distribution patterns slope towards the HREE end. Eu and Ce show positive anomalies. The calcite veins are enriched in incompatible elements (Rb, Sr, Hf, and Ta) and depleted in K. The trace element ratios of the samples plot in the CHARAC field, indicating an igneous origin. In the εNd (t) vs. (87Sr/86Sr) i diagram the Chiweigou carbonatite plots close to Mesozoic carbonatites from the adjacent NCC, and the evolutionary trend is from primary mantle to an enriched mantle I-type. Based on our analytical results, and taking into account previous research, we conclude that the Chiweigou calcite veins are carbonatites, that were derived from an end-member EMI-type mantle source that had been metasomatized by highly differentiated C–H–O supercritical fluids. The Au was probably dispersed by and precipitated from colloidal Au–Si complexes (AuH 3 SiO 4). The geochemical characteristics of the contemporary andesitic tuffs and diorite porphyrite indicate that the formation of the Chiweigou Au-bearing calcite veins resulted from extensional tectonics related to Early Cretaceous subduction of the Pacific Plate. During the early stages of intense extension (140 Ma), the carbonatite magmas ascended rapidly along extensional faults, and when they arrived in the shallow crust they mixed with meteoric water to produce the alkali metasomatism (fenitization) and the precipitation of Au as temperatures and pressures fell, thus forming the Au-bearing calcite veins and related mineralization of the Chiweigou deposit. [ABSTRACT FROM AUTHOR]