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To explore the mechanism of action of Bacillus velezensis against sweet cherry soft rot disease, the inhibitory effect of Bacillus velezensis KT against Rhizopus stolonifer LC-7 in vitro and in inoculated sweet cherry fruits, and the effect of B. velezensis KT on defense-related enzyme activities were investigated. Besides, the expression of genes related to secondary metabolite synthesis and biological control in B. velezensis KT during the interaction with R. stolonifer was also analyzed by transcriptomics. The results showed that the percentage inhibition of 1 × 109 CFU/mL B. velezensis KT suspension against mycelial growth of R. stolonifer LC-7 was 87.12%, and the percentage of spore germination and germ length of R. stolonifer LC-7 in the presence of B. velezensis KT were 21.54% and 11.45 μm, respectively. At 48 h after being treated with 1 × 109 CFU/mL B. velezensis KT suspension, the incidence of soft rot in cherry fruits was about 20% and was about 80% lower than that in the control group. B. velezensis KT suspension inhibited the activity of polyphenoloxidase (PPO) and lipoxidase (LOX), increased the activity of peroxidase (POD), phenylalanine ammonia lyase (PAL) chitinase (CHI) and β-1,3-glucanase (GLU), and improved disease resistance and antioxidant capacity in cherry fruits. It was observed by scanning electron microscopy that after co-cultured with B. velezensis KT, the morphology of the mycelia and spores of R. stolonifer LC-7 was distorted and malformed. Transcriptomic analysis showed that the expression of pksIJ in the biosynthetic gene cluster for antibiotic bacillaene and tuaAGE in the biosynthetic gene cluster for teichuronic acid were up-regulated, and the differentially expressed genes were mainly concentrated in ribonucleoprotein complex assembly, subunit assembly and ribosomal assembly during biological processes. The B. velezensis KT could directly inhibit R. stolonifer LC-7 probably through nutritional and spatial competition and secreting anti-bacterial substances and could also induce disease resistance in sweet cherry fruits. The results showed that B. velezensis KT had an obvious control effect on sweet cherry soft rot caused by R. stolonifer LC-7, making it a potential biocontrol agent.

In recent years, frequent conflicts in the South Sea of China have hindered peaceful Chinese development processes. For the first time, this study used political geography and territory to examine the process of interplaying national cartographic practices and power relations in this space. Combined with a previous discussion on territory and cartography, this study proposed a national cartographic analysis framework from the territory and applied it to the cartography of the South Sea of China. First, we performed a longitudinal comparison of cartographic evolution in the South Sea of China between China and the United States. Then, a longitudinal comparison of expressions between China and the United States was performed for three aspects of cartographic practice. The longitudinal comparison showed that the evolution of South Sea of China cartography resulted in a more complete sea area, standardized island names, and a sea boundary line that appears in China. In the United States, the South Sea of China showed enlarged sea areas, but the overall picture was incomplete. According to the longitudinal comparison, the United States differs from China in the following three aspects of the cartography of the South Sea of China: sea area, status of islands and reefs, and sea boundaries. In summary, we can draw three conclusions. 1) In China and the United States, the cartographic evolution of the sea areas of the South Sea of China, the names of islands and reefs, and the expression of sea boundaries reflect the influence of the country's power. 2) The difference in the cartography of the South Sea of China between China and the United States stems from the need to safeguard the core interests of the country. China, through the territorialization of cartography, has strengthened the maritime jurisdiction of the South Sea of China, increased awareness of national sea rights internally, and declared the sovereignty of the South Sea of China externally. However, the United States has emphasized the public seas and multinational attributes of the South Sea of China through cartographic territorialization. 3) As a territorial tool, a map presents the Chinese story of the South Sea of China on the international stage and may also clearly express China's consistent and clear position on the sovereignty of the islands and surrounding waters of the South Sea of China. The territorial expression of the South Sea of China should be strengthened from the following three aspects: map rights protection, map innovation, and map publicity. Thus, cartography may play a more important role in the governance of China's maritime territory in the South Sea of China.