The cultivation of Panax plants is hindered by replanting problems, which may be caused by plantdriven changes in the soil microbial community. Inoculation with microbial antagonists may efficiently alleviate replanti...The cultivation of Panax plants is hindered by replanting problems, which may be caused by plantdriven changes in the soil microbial community. Inoculation with microbial antagonists may efficiently alleviate replanting issues. Through high-throughput sequencing, this study revealed that bacterial diversity decreased,whereas fungal diversity increased, in the rhizosphere soils of adult ginseng plants at the root growth stage under different ages. Few microbial community, such as Luteolibacter, Cytophagaceae, Luteibacter, Sphingomonas,Sphingomonadaceae, and Zygomycota, were observed; the relative abundance of microorganisms, namely,Brevundimonas, Enterobacteriaceae, Pandoraea, Cantharellales, Dendryphion, Fusarium, and Chytridiomycota,increased in the soils of adult ginseng plants compared with those in the soils of 2-year-old seedlings. Bacillus subtilis 50-1, a microbial antagonist against the pathogenic Fusarium oxysporum, was isolated through a dual culture technique. These bacteria acted with a biocontrol efficacy of 67.8%. The ginseng death rate and Fusarium abundance decreased by 63.3% and 46.1%, respectively, after inoculation with B. subtilis 50-1. Data revealed that microecological degradation could result from ginseng-driven changes in rhizospheric microbial communities;these changes are associated with the different ages and developmental stages of ginseng plants. Biocontrol using microbial antagonists alleviated the replanting problem.展开更多
Panax notoginseng is famous for its important therapeutic effects. Saponins are bioactive compounds found in different parts and developmental stages of P. notoginseng plants. Thus, it is urgently to study saponins di...Panax notoginseng is famous for its important therapeutic effects. Saponins are bioactive compounds found in different parts and developmental stages of P. notoginseng plants. Thus, it is urgently to study saponins distribution in different parts and growth ages of P. notoginseng plants. In this study,potential biomarkers were found, and their chemical characteristic differences were revealed through metabolomic analysis. High-performance liquid chromatography data indicated the higher content of saponins(i.e., Rg1, Re, Rd, and Rb1) in the underground parts than that in the aerial parts. 20(S)-Protopanaxadiol saponins were mainly distributed in the aerial parts. Additionally, the total saponin content in the 3-year-old P. notoginseng plant(188.0 mg/g) was 1.4-fold higher than that in 2-year-old plant(130.5 mg/g). The transcriptomic analysis indicated the tissue-specific transcription expression of genes, namely, PnFPS, PnSS, PnSE1, PnSE2, and PnDS, which encoded critical synthases in saponin biosyntheses. These genes showed similar expression patterns among the parts of P. notoginseng plants.The expression levels of these genes in the flowers and leaves were 5.2 fold higher than that in the roots and fibrils. These results suggested that saponins might be actively synthesized in the aerial parts and transformed to the underground parts. This study provides insights into the chemical and genetic characteristics of P. notoginseng to facilitate the synthesis of its secondary metabolites and a scientific basis for appropriate collection and rational use of this plant.展开更多
Indications of buried lunar bedrock may help us to understand the tectonic evolution of the Moon and provide some clues for formation of lunar regolith. So far, the information on distribution and burial depth of luna...Indications of buried lunar bedrock may help us to understand the tectonic evolution of the Moon and provide some clues for formation of lunar regolith. So far, the information on distribution and burial depth of lunar bedrock is far from sufficient. Due to good penetration ability, microwave radiation can be a potential tool to ameliorate this problem. Here, a novel method to estimate the burial depth of lunar bedrock is presented using microwave data from Chang＇E-1 （CE-1） lunar satellite. The method is based on the spatial variation of differences in brightness temperatures between 19.35 GHz and 37.0 GHz （ATB）. Large differences are found in some regions, such as the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, and the highland east of Mare Smythii. Interestingly, a large change of elevation is found in the corresponding region, which might imply a shallow burial depth of lunar bedrock. To verify this deduction, a theoretical model is derived to calculate the ATB. Results show that ATB varies from 12.7 K to 15 K when the burial depth of bedrock changes from 1 m to 0.5 m in the equatorial region. Based on the available data at low lunar latitude （30°N-30°S）, it is thus inferred that the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, the highland located east of Mare Smythii, the edge of Pasteur and Chaplygin are the areas with shallow bedrock, the burial depth is estimated between 0.5 m and 1 m.展开更多
基金supported by grants from the National Science Foundation of China(81603238)
文摘The cultivation of Panax plants is hindered by replanting problems, which may be caused by plantdriven changes in the soil microbial community. Inoculation with microbial antagonists may efficiently alleviate replanting issues. Through high-throughput sequencing, this study revealed that bacterial diversity decreased,whereas fungal diversity increased, in the rhizosphere soils of adult ginseng plants at the root growth stage under different ages. Few microbial community, such as Luteolibacter, Cytophagaceae, Luteibacter, Sphingomonas,Sphingomonadaceae, and Zygomycota, were observed; the relative abundance of microorganisms, namely,Brevundimonas, Enterobacteriaceae, Pandoraea, Cantharellales, Dendryphion, Fusarium, and Chytridiomycota,increased in the soils of adult ginseng plants compared with those in the soils of 2-year-old seedlings. Bacillus subtilis 50-1, a microbial antagonist against the pathogenic Fusarium oxysporum, was isolated through a dual culture technique. These bacteria acted with a biocontrol efficacy of 67.8%. The ginseng death rate and Fusarium abundance decreased by 63.3% and 46.1%, respectively, after inoculation with B. subtilis 50-1. Data revealed that microecological degradation could result from ginseng-driven changes in rhizospheric microbial communities;these changes are associated with the different ages and developmental stages of ginseng plants. Biocontrol using microbial antagonists alleviated the replanting problem.
基金supported by grants from the National Natural Science Foundation of China(No.81603238)
文摘Panax notoginseng is famous for its important therapeutic effects. Saponins are bioactive compounds found in different parts and developmental stages of P. notoginseng plants. Thus, it is urgently to study saponins distribution in different parts and growth ages of P. notoginseng plants. In this study,potential biomarkers were found, and their chemical characteristic differences were revealed through metabolomic analysis. High-performance liquid chromatography data indicated the higher content of saponins(i.e., Rg1, Re, Rd, and Rb1) in the underground parts than that in the aerial parts. 20(S)-Protopanaxadiol saponins were mainly distributed in the aerial parts. Additionally, the total saponin content in the 3-year-old P. notoginseng plant(188.0 mg/g) was 1.4-fold higher than that in 2-year-old plant(130.5 mg/g). The transcriptomic analysis indicated the tissue-specific transcription expression of genes, namely, PnFPS, PnSS, PnSE1, PnSE2, and PnDS, which encoded critical synthases in saponin biosyntheses. These genes showed similar expression patterns among the parts of P. notoginseng plants.The expression levels of these genes in the flowers and leaves were 5.2 fold higher than that in the roots and fibrils. These results suggested that saponins might be actively synthesized in the aerial parts and transformed to the underground parts. This study provides insights into the chemical and genetic characteristics of P. notoginseng to facilitate the synthesis of its secondary metabolites and a scientific basis for appropriate collection and rational use of this plant.
基金This study was supported by West Light Foundation of the Chinese Academy of Sciences, Knowledge Innovation Program of the Chinese Academy of Sciences （Lunar Program of Geochemical Institute）, and the National Natural Science Foundation of China （Grant Nos. 41373067 and 40803019）.
文摘Indications of buried lunar bedrock may help us to understand the tectonic evolution of the Moon and provide some clues for formation of lunar regolith. So far, the information on distribution and burial depth of lunar bedrock is far from sufficient. Due to good penetration ability, microwave radiation can be a potential tool to ameliorate this problem. Here, a novel method to estimate the burial depth of lunar bedrock is presented using microwave data from Chang＇E-1 （CE-1） lunar satellite. The method is based on the spatial variation of differences in brightness temperatures between 19.35 GHz and 37.0 GHz （ATB）. Large differences are found in some regions, such as the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, and the highland east of Mare Smythii. Interestingly, a large change of elevation is found in the corresponding region, which might imply a shallow burial depth of lunar bedrock. To verify this deduction, a theoretical model is derived to calculate the ATB. Results show that ATB varies from 12.7 K to 15 K when the burial depth of bedrock changes from 1 m to 0.5 m in the equatorial region. Based on the available data at low lunar latitude （30°N-30°S）, it is thus inferred that the southwest edge of Oceanus Procellarum, the area between Mare Tranquillitatis and Mare Nectaris, the highland located east of Mare Smythii, the edge of Pasteur and Chaplygin are the areas with shallow bedrock, the burial depth is estimated between 0.5 m and 1 m.
