Genome resequencing reveals the genetic basis of population evolution, local adaptation, and rewiring of the rhizome metabolome in Atractylodes lancea.

The formation of high-quality Chinese medicinal materials is a micro-evolutionary process of multiple genes involving quantitative inheritance under environmental stress. Atractylodes lancea is a traditionally used medicinal plant in China that is broadly distributed and possesses a considerable amount of essential oils. However, to date, limited research has been conducted to characterize the genetics and metabolites of A. lancea shaped by natural variation. Hence, we assembled a high-quality genome of A. lancea, featuring a contig N50 of 1.18 Mb. We further integrated population resequencing of A. lancea and conducted analyses to characterize its genetic diversity, population evolution, and rewiring of volatile metabolites. The natural variation effect exerted significant pressure on A. lancea from different geographic locations, resulting in genetic differentiation among three groups. Correlation analysis of metabolites in A. lancea revealed significant natural variations of terpenoids, heterocyclic compounds, ketones, and esters. We also found that 427 metabolites displayed noteworthy divergence due to directional selection. Additionally, our genome-wide association studies on the metabolome for medicinal quality traits identified several candidate genes, such as AlZFP706 and AlAAHY1, exhibiting significant correlations with atractylodin and hinesol levels, respectively. Overall, this study provides an intricate genomic resource for A. lancea, thereby expanding our understanding of the effect of natural variation on metabolites and facilitating the genetic improvement of its medicinal properties.

[Effect of combined application of organic and chemical fertilizers on yield and quality of Epimedium pubescens].

To investigate the effects of different ratios of organic and chemical fertilizers on the yield and quality of Epimedium pubescens,so as to provide a scientific basis for the fertilization of high-yield and high-quality E. pubescens cultivation. In this experiment,a field plot test was conducted,and CK(without fertilizer) was set as the control group,with five treatment groups with different ratios of organic fertilizers and chemical fertilizers set up,namely OF0(100% chemical fertilizers),OF25(25% organic fertilizers),OF50(50% organic fertilizers),OF75(75% organic fertilizers),and OF100(100% organic fertilizers). The effects of different fertilization patterns on the agronomic traits,yield,effective component content,nutrient accumulation,and soil physicochemical properties of E. pubescens were determined,and the yield and quality of the medicinal herb were comprehensively evaluated by using the CRITIC weights method. It was found that the herb yield of each treatment group was significantly increased compared with the CK group,although the yield of the groups with both organic fertilizer and chemical fertilizer was slightly lower than that of OF0. However,there was no significant difference,which indicated that the organic fertilizer combined with chemical fertilizer could ensure the herb yield. With the increase in organic fertilizer ratios,the medicinal components epimedin A,epimedin B,and epimedin C showed a tendency of first increasing and then decreasing,with the highest content in the OF25,while icariin showed a rising trend,with the best in the OF100. However,overall,the total flavonol glycosides ABCI accumulated the most in the OF25. The results of the CRITIC method showed that the top three fertilization treatments in terms of the comprehensive scores of the medicinal herb were OF25,OF50,and OF75. Organic fertilizer combined with chemical fertilizer is conducive to improving the soil's fertilizer holding and supply capacity,and the soil indexes are optimal in OF100. The soil enzyme activity is the highest in OF75. Meanwhile,organic fertilizer combined with chemical fertilizer can help the plant's uptake and accumulation of nutrients,and OF25 shows the most obvious effect.By comprehensively considering the influence of different ratios of organic and chemical fertilizers on the yield,effective component content,nutrient accumulation,and other indexes of E. pubescens,it is recommended that a 25% ratio(7 500 kg·hm~(-2)) of organic fertilizers and chemical fertilizers should be used in E. pubescens production in the first year,so as to promote the E. pubescens industry to increase yield and improve quality.

Quality evaluation and identification of Houttuynia cordata bleached with sodium metabisulfite based on whole spectrum metabolomics.

Houttuynia Cordata (HC) is a widely distributed plant in Asia and is used extensively for both food and medicinal purposes. A preliminary investigation found that HC is often bleached with sodium metabisulfite solution during its field processing, leading to health risks. In this study, the effects of sodium metabisulfite on the quality of HC were comprehensively evaluated using volatile and non-volatile targeted metabolomic methods. The results revealed a positive correlation between the extent of chemical composition changes and the bleaching time. These notable changes mainly occurred at the initial stage of bleaching. Subsequently, an untargeted UPLC/Q-TOF MS method was used to explore the potential chemical bleaching markers in bleached HC. The marker 1-hydroxy-3-oxodecane-1-sulfonic acid was subsequently prepared, isolated, and identified. Market sample verification further validated the accuracy and effectiveness of this marker.

A prenyltransferase participates in the biosynthesis of anthraquinones in Rubia cordifolia.

Anthraquinones (AQs) constitute the largest group of natural quinones, which are used as safe natural dyes and have many pharmaceutical applications. In plants, AQs are biosynthesized through two main routes: the polyketide pathway and the shikimate pathway. The latter primarily forms alizarin-type AQs, and the prenylation of 1,4-dihydroxy-2-naphthoic acid (DHNA) is the first pathway-specific step. However, the prenyltransferase (PT) responsible for this key step remains uncharacterized. In this study, the cell suspension culture of Madder (Rubia cordifolia), a plant rich in alizarin-type AQs, was discovered to be capable of prenylating DHNA to form 2-carboxyl-3-prenyl-1,4-naphthoquinone and 3-prenyl-1,4-naphthoquinone. Then, a candidate gene belonging to the UbiA superfamily, R. cordifoliadimethylallyltransferase 1 (RcDT1), was shown to account for the prenylation activity. Substrate specificity studies revealed that the recombinant RcDT1 recognized naphthoic acids primarily, followed by 4-hydroxyl benzoic acids. The prenylation activity was strongly inhibited by 1,2- and 1,4-dihydroxynaphthalene. RcDT1 RNA interference significantly reduced the AQs content in R. cordifolia callus cultures, demonstrating that RcDT1 is required for alizarin-type AQs biosynthesis. The plastid localization and root-specific expression further confirmed the participation of RcDT1 in anthraquinone biosynthesis. The phylogenetic analyses of RcDT1 and functional validation of its rubiaceous homologs indicated that DHNA-prenylation activity evolved convergently in Rubiaceae via recruitment from the ubiquinone biosynthetic pathway. Our results demonstrate that RcDT1 catalyzes the first pathway-specific step of alizarin-type AQs biosynthesis in R. cordifolia. These findings will have profound implications for understanding the biosynthetic process of the anthraquinone ring derived from the shikimate pathway.

Authenticating the geographic origins of Atractylodes lancea rhizome chemotypes in China through metabolite marker identification.

Introduction: Atractylodes lancea is widely distributed in East Asia, ranging from Amur to south-central China. The rhizome of A. lancea is commonly used in traditional Chinese medicine, however, the quality of products varies across different regions with different geochemical characteristics. Method: This study aimed to identify the chemotypes of A. lancea from different areas and screen for chemical markers by quantifying volatile organic compounds (VOCs) using a targeted metabolomics approach based on GC-MS/MS. Results: The A. lancea distributed in Hubei, Anhui, Shaanxi, and a region west of Henan province was classified as the Hubei Chemotype (HBA). HBA is characterized by high content of ß-eudesmol and hinesol with lower levels of atractylodin and atractylon. In contrast, the Maoshan Chemotype (MA) from Jiangsu, Shandong, Shanxi, Hebei, Inner Mongolia, and other northern regions, exhibited high levels of atractylodin and atractylon. A total of 15 categories of VOCs metabolites were detected and identified, revealing significant differences in the profiles of terpenoid, heterocyclic compound, ester, and ketone among different areas. Multivariate statistics indicated that 6 compounds and 455 metabolites could serve as candidate markers for differentiating A. lancea obtained from the southern, northern, and Maoshan areas. Discussion: This comprehensive analysis provides a chemical fingerprint of selected A. lancea. Our results highlight the potential of metabolite profiling combined with chemometrics for authenticating the geographical origin of A. lancea.

The discovery and characterization of AeHGO in the branching route from shikonin biosynthesis to shikonofuran in Arnebia euchroma.

Shikonin derivatives are natural naphthoquinone compounds and the main bioactive components produced by several boraginaceous plants, such as Lithospermum erythrorhizon and Arnebia euchroma. Phytochemical studies utilizing both L. erythrorhizon and A. euchroma cultured cells indicate the existence of a competing route branching out from the shikonin biosynthetic pathway to shikonofuran. A previous study has shown that the branch point is the transformation from (Z)-3''-hydroxy-geranylhydroquinone to an aldehyde intermediate (E)-3''-oxo-geranylhydroquinone. However, the gene encoding the oxidoreductase that catalyzes the branch reaction remains unidentified. In this study, we discovered a candidate gene belonging to the cinnamyl alcohol dehydrogenase family, AeHGO, through coexpression analysis of transcriptome data sets of shikonin-proficient and shikonin-deficient cell lines of A. euchroma. In biochemical assays, purified AeHGO protein reversibly oxidized (Z)-3''-hydroxy-geranylhydroquinone to produce (E)-3''-oxo-geranylhydroquinone followed by reversibly reducing (E)-3''-oxo-geranylhydroquinone to (E)-3''-hydroxy-geranylhydroquinone, resulting in an equilibrium mixture of the three compounds. Time course analysis and kinetic parameters showed that the reduction of (E)-3''-oxo-geranylhydroquinone was stereoselective and efficient in presence of NADPH, which determined that the overall reaction proceeded from (Z)-3''-hydroxy-geranylhydroquinone to (E)-3''-hydroxy-geranylhydroquinone. Considering that there is a competition between the accumulation of shikonin and shikonofuran derivatives in cultured plant cells, AeHGO is supposed to play an important role in the metabolic regulation of the shikonin biosynthetic pathway. Characterization of AeHGO should help expedite the development of metabolic engineering and synthetic biology toward production of shikonin derivatives.

Authenticating the geographical origin of the Chinese yam (Tiegun) with stable isotopes and multiple elements.

The Chinese yam, an important orphan crop with both high nutrient and health promoting value, is mainly produced in the Yellow-Huai-Hai plain near the river basins in China. The protected designation of origin (PDO)-labeled Chinese yam differs greatly from others in market acceptance and price, which has led to fakes and the need for reliable authentication methods. Hence, stable isotope ratios of δ 13C, δ 15N, δ 2D, and δ 18O and 44 multielemental contents were used to explore the authentication of geographical origins and the effect of environmental factors. Twenty-two elements and δ 15N were selected as the key variables to authenticate Chinese yams from three river basins as well as to authenticate them among traditional PDOs and others in the Yellow River basin. Moreover, six environmental factors, including the moisture index, maximum temperature, photosynthetically active radiation, soil organic carbon, total nitrogen and pH, were found to be highly related to these variances.

[Overview of Chinese medicinal materials industry in 2021 and development suggestions].

This paper introduced the overview of the "eight trends" of Chinese medicinal materials(CMM) industry in 2021, analyzed the problems of CMM production, and put forward development suggestions. Specifically, "eight trends" could be summarized as follows.(1) The growing area of CMM tended to be stable, and some provinces began to release the local catalog of Dao-di herbs.(2) The protection process of new varieties accelerated, and a number of excellent varieties were bred.(3) The theory of ecological cultivation was further enriched, and the demonstration effect of ecological cultivation technology was prominent.(4) Some CMM realized complete mechanization and formed typical model cases.(5) The number of cultivation bases using the traceability platform increased, and provincial internet trading platforms were set up.(6) The construction of CMM industrial clusters accelerated, and the number of provincial-level regional brands increased rapidly.(7) Many new agricultural business entities were founded nationwide, and a variety of methods were used to drive the intensified development of CMM.(8) A number of local TCM laws were promulgated, and the management regulation of food and medicine homology substances catalogs was issued. On this basis, four suggestions for CMM production were proposed.(1) It is suggested to speed up the formulation of the national catalog of Dao-di herbs and carry out the certification of Dao-di herbs production bases.(2) Ecological planting of forest and grassland medicine should be further strengthened in terms of technical research and promotion based on the principle of ecological priority.(3) The basic work of disaster prevention should be paid more attention and technical measures for disaster mitigation should be developed.(4) The planted area of commonly used CMM should be incorporated into the national regular statistical system.

[Strategic analysis on value accounting and realization of ecological products of Chinese materia medica].

Green agriculture has become the "wind vane" of agricultural reform in the new era. The development concept of Chinese materia medica(CMM) ecological agriculture and the emergence of new technologies provide momentum for the supply of high-quality green ecological products. As special ecological products, Dao-di herbs have medicinal, economic, ecological, and cultural values. The ecological planting of CMM and the value realization of ecological products are of great significance for the high-quality development of CMM agriculture and for prospering agriculture by improving quality. Therefore, this paper reviews the development status and typical cases, and puts forward the advantages of ecological product value realization of Dao-di herbs. On this basis, a value accounting system for ecological products of CMM was constructed from three aspects: supply services, ecological services, and cultural services. Finally, the suggestions for realizing the value of CMM ecological products are put forward.(1)It is suggested to strengthen the practice of ecological planting and production of CMM, and innovate the value realization model of ecological products.(2)The ecological planting bases of Dao-di herbs should be constructed to enhance the supply capacity of high-quality ecological products.(3)The quality and safety of ecological CMM should be improved to create the ecological planting brand of Dao-di herbs.(4)The ecological product value system and mechanism should be improved for realizing the value of CMM ecological products.(5)The education and publicity should be strengthened to raise the public awareness of the value of CMM ecological products.

Maize intercropping enriches plant growth-promoting rhizobacteria and promotes both the growth and volatile oil concentration of Atractylodes lancea.

In the Atractylodes lancea (A. lancea)-maize intercropping system, maize can promote the growth of A. lancea, but it is unclear whether this constitutes an aboveground or belowground process. In this study, we investigated the mechanisms of the root system interaction between A. lancea and maize using three different barrier conditions: no barrier (AI), nylon barrier (AN), and plastic barrier (AP) systems. The biomass, volatile oil concentration, physicochemical properties of the soil, and rhizosphere microorganisms of the A. lancea plant were determined. The results showed that (1) the A. lancea - maize intercropping system could promote the growth of A. lancea and its accumulation of volatile oils; (2) a comparison of the CK, AI, and AP treatments revealed that it was the above-ground effect of maize specifically that promoted the accumulation of both atractylon and atractylodin within the volatile oils of A. lancea, but inhibited the accumulation of hinesol and ß-eudesmol; (3) in comparing the soil physicochemical properties of each treatment group, intercropping maize acidified the root soil of A. lancea, changed its root soil physicochemical properties, and increased the abundance of the acidic rhizosphere microbes of A. lancea at the phylum level; (4) in an analysis of rhizosphere microbial communities of A. lancea under different barrier systems, intercropping was found to promote plant growth-promoting rhizobacteria (PGPR) enrichment, including Streptomyces, Bradyrhizobium, Candidatus Solibacter, Gemmatirosa, and Pseudolabrys, and the biomass of A. lancea was significantly influenced by PGPR. In summary, we found that the rhizosphere soil of A. lancea was acidified in intercropping with maize, causing the accumulation of PGPR, which was beneficial to the growth of A. lancea.

[Current status and development strategy of ISO/TC 249 standards for Chinese materia medica].

The internationalization of traditional Chinese medicine(TCM) is one of the strategic development objectives in China, which has been incorporated into the national strategy as an important part of the Belt and Road Initiative development strategy. As the basis and prerequisite of TCM development, Chinese materia medica(CMM) has a direct impact on the internationalization of TCM. The International Organization for Standardization(ISO) is a global organization composed of national standardization bodies, and the ISO standards impact the world's economy, trade, communication and cooperation. Based on a brief introduction to ISO/Traditional Chinese Medicine Technical Committee(ISO/TC 249), this study elaborates the necessity of establishing ISO standards for CMM and analyzes the current status and challenges faced by the formulation of international standards for CMM. Finally, this study puts forward the development strategy of international standards for CMM. Specifically, efforts should be made to develop top-level design with international market demands as the guidance and improve the quality of standards to accelerate the transformation of domestic high-quality standards into international standards. Moreover, measures should be taken to give full play to the positive role of enterprises in the formulation of standards, vigorously cultivate compound talents for international standardization of TCM, and constantly strengthen international cooperation. The experience and thinking are of guiding significance for the scientific, efficient and reasonable formulation of high-quality ISO standards for CMM in the future.

[Chinese medicinal materials industry during the 14th Five-Year Plan period: trends and development suggestions].

This study steps through the future perspectives and gives the development suggestions of Chinese medicinal materials(CMM) industry by presenting the characteristics and open problems during the 13 th Five-Year Plan period. The development of CMM industry presents the following trends:(1)the development of Dao-di herbs speeds up with the increasing demand for high-quality CMM;(2)the mismatch between supply and demand is aggravating, which presses for supply-side structural reform;(3)ecological planting will become the core mode of production and bolster rural revitalization;(4)the demand for CMM with both medical and edible values keeps growing, and the antibiotic-free feed policy brings significant opportunities;(5)the "Internet Plus CMM" wave emerges, which promotes the construction of traceability system. Finally, we put forward the following suggestions for the sustainable development of CMM industry:(1)optimizing the layout for the production of Dao-di herbs according to local conditions;(2)strengthening the commercialization of the seeds and the breeding, multiplication, and extension of CMM to accelerate the realization of specialized seed production, mechanized seed processing, localized variety layout, and county-based unified seed supply;(3)ensuring the safety of pesticide use and accelerating the registration of special pesticides;(4)promoting both theoretical and practical research on ecological production of CMM;(5)publicizing the demonstration and popularization of CMM traceability system. Overall, significant progress has been achieved in the CMM industry during the 13 th Five-Year Plan period, and this industry is in a critical stage of high-quality development, facing both challenges and opportunities.

[Problems and strategy of further development of Chinese medicinal materials with edible values].

"Medicine and food homology" is a precious health care concept rooted in the culture of Chinese medicine and plays an important role in the development of the national health industry. It is consistent with the current global trend that food and medicine are mutually penetrating. Accordingly, the Chinese medicinal materials with edible values have an increasing production scale. Especially, in the context that the development of Chinese medicinal materials is switching from pursuing quantity to quality, the food field has become the main market for the new production capacity of Chinese medicinal materials, which has presented a broad prospect. However, the quality standards of raw materials, production methods, and administration ways vary between the materials for edible and medicinal purposes. Specifically, the food for medicinal use on the market cannot meet the quality standards of medicinal mate-rials, while the medicinal materials fail to meet the taste requirements as food. As a result, these problems cause difficulties in market circulation and supervision. In this paper, we analyzed the formation of Chinese medicinal materials with edible values, compared the food with medicinal value, common food, and functional food, and analyzed the different quality requirements of Chinese medicinal materials used in different scenarios. Further, we advised the differential development of Chinese medicinal materials in different directions(edible or medicinal use) from production to supervision. Including:(1) In the variety registration of Chinese medicinal materials with edible values, the variety breeding direction should be announced according to the requirements that medicinal materials care more about the content of active ingredients and food use materials preferentially need to meet the requirements of edible palatability.(2) Differentiation can be reflected in the selection of cultivation mode and planting and processing technology of medicinal materials, The differential production technical specification of medicinal materials with edible values should be developed. Such as the "simulated cultivation" mode is encouraged in the plant of medicinal materials to ensure its quality and the strict management of inputs and sufficient cultivation years should be guaranteed. While for edible medicinal materials, more kinds of cultivation techniques can be selected according to their processing methods.(3) The market supervision of medicinal materials with edible values should be guided by the purpose of their sales and use, which depends on the accurately recognize of the relationship between the properties of medicinal materials with edible values and the situation of pharmacopeia collection.(4) During publicity, when used as ordinary food and health food medi-cinal materials, it should be noticed that the publicity of the product's efficacy must meet the requirements of corresponding regulations.

[Research progress and prospect of endophytes from medicinal plant Atractylodes lancea].

The endophytes of medicinal plants play an important role in promoting the quality formation of the host. Therefore, this paper made a review of endophytes of medicinal plant Atractylodes lancea. According to previous studies, A. lancea boasts endophytes, such as fungi, bacteria, and actinomycetes, among which the beneficial microorganisms help the growth and development of A. lancea. There is a close interaction between the volatile oil of A. lancea and endophytes. Different endophytes vary in regulating the composition and content of the volatile oil of A. lancea, which might contribute to the quality formation of A. lancea. However, the information of the endophytic flora of A. lancea obtained by traditional culture and isolation is not enough to reflect the real situation of the endophytes of A. lancea. Little is known about the endophytes of A. lancea from different chemical types and different habitats, which is not conducive to the study of the ecological relationship between A. lancea and endophytes and limits the development and utilization of the endophytes. Therefore, at the end of this paper, the authors put forward suggestions for future research on endophytes in A. lancea, including:(1)mining the core endophyte resources of A. lancea by combining high-throughput sequencing with traditional culture and isolation;(2)exploring the relationship between the diversity of endophytes and chemical types of A. lancea;(3)strengthening the application of endophytes in A. lancea cultivation, in order to facilitate the cultivation efficiency and quality of A. lancea.

[Current situation of nitrogen application and its effects on yield and quality of Chinese materia medica].

Nitrogen fertilizer has been the long-lasting crucial component in cultivation of Chinese materia medica(CMM) and crops for its profound effects on enhancing the productivity. In consideration of its role in better production, intensive and excessive application of N fertilizer is often found in CMM cultivation. Therefore, firstly, this review summarized various concentrations of N application with regards to different CMM and districts from the literatures published in the last two decades. The recommended concentration of nitrogen application of forty seven CMM species were covered in this review. We found that the optimum rates of nitrogen fertili-zer for different medicinal plants species were varied in the range between 0-1 035.55 kg·hm~(-2). Most of the optimum rates of nitrogen fertilizer for CMM in published researches fell between 100-199 kg·hm~(-2). The optimum rate of nitrogen fertilizer is not only related to amount of nitrogen required for different medicinal plants but also to soil fertilities of different fields. In addition, we outlined the diffe-rent effects of proper and excessive nitrogen deposition on yield of CMM. Proper nitrogen deposition benefits the yield of CMM, howe-ver, excessive nitrogen use accounts for a decrease in CMM yield. We elucidated that nutritional content, water use efficiencies, and photosynthesis capacity were major influencing factors. Researches showed that proper nitrogen fertilizer could promote the water use efficiencies of plants and boost photosynthesis. Consequently, the yield of CMM can be enhanced after nitrogen deposition. However, negative effects of nitrogen fertilizer were also found on plant including producing toxic substances to the soil and causing severe pest damages. Lastly we analyzed the impact of N fertilizer application on secondary metabolites which accounts for a large part of active pharmaceutical ingredients of CMM. It usually caused an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. The potential underlying mechanisms are the different synthetic pathways of these metabolites and the plant nutritional status. Synthesis of non-nitrogen-containing secondary metabolites like phenols can be inhibited after nitrogen application because of the competition of the same precursor substances between metabolites synthesis and plant growth. To sum up, impacts and mechanisms of nitrogen fertilizer on yield and quality enhancement of CMM were discussed in this review. Negative effects of excessive nitrogen application on CMM should be paid special attention in CMM cultivation and prescription fertilization based on the field soil quality is strongly recommended. Overall, this review aims to provides insights on improving the proper application of N fertilizer in the cultivation of CMM.

[Effects and mechanisms of nitrogen fertilizers on soil and tritrophic interactions in Chinese medicinal plants ecosystem].

Nitrogen is one of the most frequently used fertilizers in growth of Chinese medicinal plants(CMP). As in many other ecosystems, CMP ecosystem is also composed of plant-herbivore-natural enemy(tritrophic) interactions. Nitrogen fertilizer influences the growth and reproduction of CMP, and it is also able to heavily shape the ecosystem functions of CMP ecosystem through bottom-up forces. Understanding the specific effects of nitrogen fertilizer towards each trophic level will be beneficial to improve the resistance of CMP to herbivore and enhance the control efficiency of nature enemies to herbivore, and eventually, maximize the yield and quality of CMP. Most papers published on nitrogen use in plants focused mainly on the impact of nitrogen fertilization on CMP yield and quality. Influences of nitrogen application on CMP ecosystem get little attention at present. Therefore, this review summed up the potential effects of nitrogen fertilization on CMP ecosystem from perspectives of soil and tritrophic interactions. First of all, nitrogen fertilizer might decrease soil microbial biomass and altered the community structures of soil bacteria, fungi and protozoa. Negative effects of nitrogen fertilizer were found on biodiversity of soil bacteria and protozoa. Different fungi species respond differently to nitrogen fertili-zers. Nitrogen deposition can also decrease the soil pH. Decreases in soil microbial diversity and soil acidification can cause negative effects on CMP growth. In addition, nitrogen fertilizer could regulate the pest resistance of CMP including constitutive and inducible resistance. Both positive and negative effects of nitrogen application were found on pest resistance of CMP. Moreover, the development and predation of natural enemies were influenced by nitrogen deposition. Nitrogen influences natural enemies in many ways including plant volatiles, plant nutrient and structure and the supplementary food quality. Nectar and honeydew of plants and preys serve as important food source for natural enemies especially in early season when preys are still not available. Finally, the interactions between herbivores and their natural enemies were also shaped by nitrogen fertilizer in many aspects like increasing the nutritional content of prey and changing control efficiency of natural enemies. Some herbivores have evolved a strategy to sequester secondary metabolites which they absorbed from plant during their feeding. Studies showed that sequestration efficiency of secondary metabolites in prey could also be regulated by nitrogen. Parasitic, emergence, reproduction rate and longevity of parasites were found positively correlated with nitrogen deposition. Hopefully this study will shed light on practicable and economical application of nitrogen in cultivation of CMP.

[Effects and mechanisms of nitrogen application on stress resistance of Chinese materia medica].

Nitrogen fertilizers play an important role in the regulation of plant stress resistance. Impacts of nitrogen fertilizers on abiotic stress resistance and biotic stress resistance of Chinese materia medica(CMM) were summarized in this study. Adequate nitrogen application improves the abiotic stress resistance and weed resistance of CMM, however adverse effect appears when excess nitrogen is used. Generally, pest resistance decreases along with nitrogen deposition, while effects of nitrogen application on disease resistance vary with different diseases. Mechanisms underlying the impact of nitrogen fertilizers on plant stress resistance were also elucidated in this study from three aspects including physical defense mechanisms, biochemistry mechanisms and molecular defense mechanisms. Nitrogen availability modulates physical barrier of CMM like plant growth, formation of lignin and wax cuticle, and density of stomata. Growth of CMM promoted by nitrogen fertilizer may cause some decrease in pest resistance of CMM due to an increase in hiding places for pest along with plant growth. High ambient humidity caused by excessive plant growth facilitates the growth and development of CMM pathogen. Nitrogen application can also interfere with the accumulation of lignin in CMM which makes CMM more vulnerable to pest and pathogen attack. Stomatal closing delays due to nitrogen application is also a causal factor of increasing pathogen infection after nitrogen deposition. Biochemical defenses of plants are mainly achieved through nutrient elements, secondary metabolites, defense-related enzymes and proteins. Nutritional level of CMM and various antioxidant enzymes and resistance-related protein activities are elevated along with nitrogen deposition. These antioxidant enzymes can reduce the damage of reactive oxygen species content produced by plant in response to adversity and therefore enhance stress resistance of CMM. Researches showed that nitrogen application could also cause an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. Nitrogen-mediated molecular defense mechanisms includes multiple plant hormones and nitric oxide signals. Plant hormones related to plant defense like salicylic acid, jasmonic acid and abscisic acid can be modulated by nitrogen application. Negative effect of nitrogen deposition was found on salicylic acid accumulation and the expression of related plant disease resistance genes. However, jasmonic acid level can be elevated by nitrogen. Nitric oxide signals constitute an important part of nitrogen mediated defense mechanisms. Nitric oxide signaling is related to many aspects of plant immunity. The roles of nitrogen fertilizers in CMM stress resistance are complex and may vary with different CMM varieties and environments. Further studies are urgently needed to provide a comprehensive understanding of how to improve stress resistance of CMM by using fertilizers.

[Effect of combined application of inorganic and organic fertilizers on growth and quality of Salvia miltiorrhiza].

The study is aimed through field experiments to study the effect of combined application of organic and chemical fertilizers on the growth and quality of Salvia miltiorrhiza, provide ideas for reducing fertilization while increasing the efficiency as well as improving the quality of produces. The experiment included 6 treatments viz., no fertilization(CK), full application of chemical fertilizer(F), 25% orga-nic fertilizer with 75% chemical fertilizer(M25), 50% organic fertilizer with 50% chemical fertilizer(M50), 75% organic fertilizer with 25% chemical fertilizer(M75), and fully apply organic fertilizer(M100). The results showed that:(1)from the perspective of yield and economic benefits, M75 was the best and M100 second;(2)for effective components, the combined application of organic and chemical fertilizers increased the content of main water-soluble components and the total content of effective components, among which M25 and M50 were better.

Practical Protocol for Comprehensively Evaluating Sulfur-Fumigation of Baizhi Based on Metabolomics, Pharmacology, and Cytotoxicity.

Sulfur Angelicae Dahuricae Radix (Baizhi) is a common medicinal herb in Asian countries. A practical protocol combining metabolomics, pharmacology, and cytotoxicity was developed to comprehensively evaluate the influence of sulfur-fumigation on the quality of Baizhi. Furocoumarins could be transformed into sulfur-containing compounds during the sulfuring process, among which 1 and 3 were purified with relatively high abundance and identified as 3,4-dihydrobyakangelicin-4-sulfonic acid and (4R,12S)-3,4-dihydrooxypeucedanin hydrate-4-sulfonic acid (OXH-S), respectively. OXH-S was found to be an addition product of sulfite and oxypeucedanin hydrate (OXH-N). Then, the cytotoxicity and anti-inflammatory activity of OXH-N, OXH-S, and water extracts of sulfured (extraction-S), and unsulfured Baizhi (extraction-N) were evaluated. OXH-S and extraction-S were less toxic than OXH-N and extraction-N, respectively. A comparison of OXH-N with OXH-S and extraction-N with extraction-S showed no significant differences in anti-inflammatory activity. These results suggest that sulfur fumigation can reduce toxicity and does not influence the anti-inflammatory activity of Baizhi, even after chemical composition changes. The proposed protocol based on marker screening, pharmacology, and safety evaluation provides a scientific basis for the standardization and regulation of sulfured Baizhi and other medical materials.

A field trials-based authentication study of conventionally and organically grown Chinese yams using light stable isotopes and multi-elemental analysis combined with machine learning algorithms.

In this study, stable isotopes and multi-element signatures combined with chemometrics were used to distinguish conventional and organic Chinese yams based on field trials. Four light stable isotopes δD, δ13C, δ15N, δ18O, and 20 elements (e.g. Li, Na, Mn) were determined, then evaluated using significance analysis and correlation analysis, and modeling of various chemometrics methods. Consequently, the RandomForest model showed the best performance with AUC value of 0.972 and predictive accuracy of 97.3%, and Mn, Cr, Se, Na, δD, As, and δ15N were screened as significant variables. Moreover, many chemical components and antioxidant activity of yam samples were determined spectrophotometrically. The results indicated that organic yams had advantages in secondary metabolites such as polyphenol, flavonoid and saponin; conversely, conventional samples had more primary metabolites like protein and amino acids. Above all, this work provides a beneficial case in the authentication and quality evaluation of conventional and organic yams.