The Immune System and the Antiviral Responses in Chinese Giant Salamander, Andrias davidianus

The Chinese giant salamander, belonging to an ancient amphibian lineage, is the largest amphibian existing in the world, and is also an important animal for artificial cultivation in China. However, some aspects of the innate and adaptive immune system of the Chinese giant salamander are still unknown. The Chinese giant salamander iridovirus (GSIV), a member of the Ranavirus genus (family Iridoviridae), is a prominent pathogen causing high mortality and severe economic losses in Chinese giant salamander aquaculture. As a serious threat to amphibians worldwide, the etiology of ranaviruses has been mainly studied in model organisms, such as the Ambystoma tigrinum and Xenopus. Nevertheless, the immunity to ranavirus in Chinese giant salamander is distinct from other amphibians and less known. We review the unique immune system and antiviral responses of the Chinese giant salamander, in order to establish effective management of virus disease in Chinese giant salamander artificial cultivation.

First Report of Athelia rolfsii Causing Southern Blight on Sarcandra glabra in China

Sarcandra glabra, belonging to the family Chloranthaceae, is a Chinese medicinal plant. The whole dry plant can be used as a medicine; it is rich in bioactive phytochemicals that possess anti-bacterial, anti-inflammatory, anti-oxidant, and anti-tumor properties (Xie et al. 2020). The current market price of S. glabra is around US$5/kg, and the annual demand is 3 500 000~4 000 000 kg in China (Pan et al. 2007). To meet consumer demand for safe and high-quality herbal products, the artificial cultivation of S. glabra has been vigorously promoted. In 2020, it was observed that a plant disease affected S. glabra growth in Hunan province. The disease symptoms included constriction at the base of the stem, with decay and a white mycelium covering. The plants finally died with a disease incidence ranging from 15% to 20%. Using our previously published methods (Yi et al. 2019), one fungal isolate was isolated from the cultured symptomatic stem tissue on potato dextrose agar (PDA) medium and was named as Kb. The isolate was subsequently transferred into 70% glycerol for preservation. The Kb colony varied in color from white to light yellow. The septate hyphae grew rapidly on PDA medium, at approximately 25 mm/day, at 28 °C. On the fifth day, rhizomorphs were formed at the edge and on the center of the PDA plate. On the sixth day, sclerotia developed into a rapeseed shape (d = 1.2~2.3 mm) with a smooth surface, and with white, yellow, or chestnut brown coloring. Morphologically, Kb was similar to Sclerotium rolfsii (Sun et al. 2020). Vigorously growing aerial hyphae were selected for molecular identification. The internal transcribed spacers (ITS) were amplified using the primer pairs ITS1/ITS4 (Glass et al. 1995). BLAST searches against Genbank indicated that Kb’s ITS sequence shared 97% similarity with that of Athelia rolfsii (MN696630.1). Based on morphological and molecular characteristics, Kb was identified as A. rolfsii. The sequence was deposited in GenBank (MW288292). Pathogenicity tests were carried out using the following procedures. Three healthy S. glabra seedlings were inoculated at the stem base with a PDA plug (5 mm in diameter) covered with 5-day-old fungal mycelium cultured at 28 °C, while the remaining three seedlings were inoculated with distilled water only, as the control. Plants were incubated in a greenhouse at 28 °C. At 7 days post inoculation, the inoculated sites infected with the putative pathogen displayed identical constrictions as previously observed in the field. In contrast, the controls remained symptomless. The pathogen was reisolated from these infected seedlings, and its culture showed the same morphological and molecular traits as the original isolates. No pathogens were isolated from the control plants. Pathogenicity tests were repeated three times. Koch’s postulates were fulfilled. Although S. rolfsii has been previously reported to cause Southern Blight on mung bean crops in China (Sun et al. 2020), this is the first report on A. rolfsii causing similar symptoms of Southern Blight on S. glabra in Hunan Province, China. Identification of the pathogens causing each disease is important for the development of effective disease management strategies and for extensive artificial cultivation.

Response of Lamiophlomis rotata (Benth.) Kudo to degradation of alpine grasslands in the western Sichuan plateau, China

Background: Lamiophlomis rotata (Benth.)Kudo, also known as Duyiwei in China, is considered to be one of the most common Tibetan medicine. It is famous for the significant effects on improving blood circulation and relieving pain. Due to the environmental deterioration and excessive consumption, the wild resources of L.rotata is decreasing year by year. However, its artificial cultivation has not been realized. This study aimed to initially explore the adaptation mechanism of L.rotata to degraded alpine grassland, and provide reference for its wild tending and artificial cultivation.Methods: In this study, we used a sample method to conduct a population ecological survey of plants and collect plant leaf samples from mildly, moderately, and extremely degraded grassland. The content of SOD, POD, CAT, PRO, MDA, SS, SP, carotene, chlorophyll A and chlorophyll B in different sample leaves was measured by colorimetry. Microscopic characteristics of the cross-section, epidermis and submicroscopic structure of the leaves were observed and compared.Results: The density of L. rotata in moderately degraded grassland was the highest，where L. rotata had the strongest resistance. And the analysis of seven physiological indicators combined with stress resistance showed that the average content of MDA, SOD, POD, CAT and SS is the highest in L. rotata of the moderately degraded grassland. The microscopic observation showed that, by increasing the thickness of the epidermis, the density of the glandular scales, the proportion of palisade tissue and the number of gland scales, L. rotata was able to adapt to the degraded grassland. Meanwhile, morphological studies have shown that L. rotata could enhance root growth in the degraded grassland. Furthermore, in response to the degradation of alpine grassland on the Qinghai-Tibet Plateau, L. rotata population and biomass distribution in the underground parts have increased. However, L. rotata does not have a competitive advantage in mildly degraded grassland. Compare with the mildly and moderately habitat, the population of L. rotata is small in the extremely degraded habitat.Conclusion: The results showed that among the 3 levels of degraded grassland, L. rotata in the moderately degraded grassland shows the strongest resistance. This study can provide a reference for breeding and ecological planting of L. rotata, suggests that in the nursery stage, the medium degraded grassland should be chosen for ecological breeding to enhance the survival rate of seedlings. While after large-scale planting, reasonable community interventions, like the P. fruticosa+F. rubra community, should be built to simulate the yield of medicinal materials.

EXPERIMENTAL RESEARCH FOR TECHNOLOGICAL PREPARATION OF ARTEMIA (ARTEMIA) ARTIFICIAL CULTIVATION IN SALT LAKES

An integral part of the technological preparation of artificial cultivation of brine shrimp in saline water is a set of preliminary experimental work to assess the quality of cysts. It has been shown that during the winter period, activation of Artemia cysts occurs from the initial hatching values of 5-10 % to 72-99 %. The most optimal salinity range for hatching nauplii is a salinity of 20-30 g/l. With an increase in salinity above these indicators, hatching decreases. The size of hatching of Artemia depends on the salinity of a natural reservoir. In reservoirs with salinity of 50-80 g / l, higher hatching rates were obtained than with salinity of 150-160 g/l. Higher hatching rates are observed when using natural lake water for incubation. During incubation of cysts in a standard solution and fixed salinity and temperature conditions, the development rate of various stages of nauplii from the beginning of the opening of cysts (breaking stage) and pre-nauplius to active nauplii is shown. After 1.5–2 h after the mass appearance of pre-nauplii, they completely change into the nauplius stage.

PROSPECTS FOR DEVELOPMENT OF RESTAURANT BUSINESS IN AGRARIAN AND INDUSTRIAL STATE

The role of the service sector in the development of the national economy of the country is substantiated. It is proved that the artificial cultivation of the service sector in the conditions of degradation of the branch structure and the reduction of effective aggregate demand can not bring it into the rank of the engine of economic development. Methodologically substantiated the author's position regarding the synergy of the level of household income, the structure of their expenditures, the investment attractiveness of the country and the productivity of its economy. The direct-to-person segment of the service sector is also characterized by technological and technological innovation, which is reflected in the deepening of personalization of the provision of catering services.