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Objective: To compare the chemical composition of mature fruit, immature fruit, stalk and leaf of Cinnamomum migao (C. migao), and also to investigate the antioxidant capacity. Methods: The volatile oils of mature fruit, immature fruit, stalk and leaf of C. migao were extracted by hydrodistillation, and their respective components were analyzed by gas chromatography-mass spectrometry (GC-MS), the analytical results were searched and matched with Nist 17 and Wiley 275 standard mass spectra, and their relative contents were determined by peak area normalization method, the DPPH· and ABTS+· and total reducing capacity antioxidant system was also used to investigate their antioxidant effects. Results: 66 components were detected from the mature fruit volatile oil of C. migao, with a relative content of 89.365%, and the main components were n-decanoic acid (28.563%), 1,8-cineole (13.461%) and dodecanoic acid (13.279%), etc. 60 components were detected from the immature fruit volatile oil of C. migao, with a relative content of 86.2%, and the main components were 1,8-cineole (11.845%), β-phellandrene (10.831%) and α-phellandrene (9.178%), etc. 67 components were detected from the stalk volatile oil with a relative content of 55.047%, the main components were β-eudesmol (13.683%), 1-((1R,2R,3R)-2-(3- Isopropylfuran-2-yl)-3-methylcyclopentyl)ethanone (3.426%) and δ-cadinene (3.188%), etc. 50 components were detected from the leaf volatile oil with a relative content of 64.389%, the main components were 1-((1R,2R,3R)-2-(3-Isopropylfuran-2-yl)-3-methylcyclopentyl)ethanone (11.259%), spathulenol (8.473%) and 3,5-bis(1,1-dimethylethyl)-2-hydroxy-benzaldehyde (7.79%), etc. The antioxidant results indicating that the mature fruit volatile oil had the best antioxidant effect and the stalk volatile oil had the worst antioxidant effect. Correlation analysis showed that hydrocarbon and acid components were positively correlated with antioxidant capacity. Cluster analysis classified the mature and immature fruit into one category, and the stalk and leaf into one category. Conclusion: The components and contents of the volatile oil from different parts of C. migao varied greatly, but all of them had good antioxidant ability, which could lay the foundation for the subsequent study.

Aims: Roots are key parts of plant material circulation and energy flow, creating two distinct niches for the plant microbiome, such as the rhizosphere and root endosphere, which interact to maintain plant growth and health. In this study, two niches of plant rhizosphere and root endosphere were selected to study the composition and differences of fungi communities in order to better understand how differences in the structure and function of plant fungi communities affect plant health. Methods and results: The community structure, diversity, and ecological function of fungi in the rhizosphere and root endosphere of Cinnamomum migao were studied using high-throughput sequencing techniques, traditional culture methods, and the FUNGuild database. The results of the analysis of alpha diversity showed that the diversity of rhizosphere fungal communities in C. migao was much higher than that of root endosphere communities. Some similarities and differences were noted between the two niche fungal communities, and some fungi had niche preferences. Functional prediction results demonstrated that fungi in the rhizosphere and root endosphere adopt multiple trophic modes, mostly saprophytic fungi. Conclusions: This study provided a basis for an in-depth understanding of the structural variation, niche differentiation, and function of plant root-related fungal microbiota. We believe that it could provide guidance on the subsequent development of beneficial fungi. [ABSTRACT FROM AUTHOR]

Cinnamomum migao H. W. Li is an evergreen tree belonging to the Lauraceae family and is endemic to China. Previous studies have found that the rhizosphere microbiome associated with the C. migao wild population plays an essential role in the production of fruit chemical components. However, it remains unknown whether the rhizosphere microbiome affects the production of fruit chemical compounds in cultivated C. migao population. Herein, we studied a 10-year-old fruit-bearing population of C. migao and used techniques such as culturing, amplicon sequencing, and metagenomic sequencing to explore the changes in the rhizosphere microbial community structure over three periods. Meanwhile, the molecular ecological network of the rhizosphere microbiome was constructed based on random matrix theory. The unidentified species were found to belong to fungi and Capnodiales. Sphingomonas sp. mm-1 and Streptomyces scabiei in network hubs were recognized in over three fruiting periods. Further, four network hubs were significantly related to fruit chemical compounds production in C. migao. The higher the number of species annotated, the better the explanation for fruit chemical compounds production in C. migao. The rhizosphere microbiome was found to exert a synergistic effect by increasing fruit chemical component production in C. migao. This was evinced through KEGG analysis, which revealed the different metabolic activities affected by the rhizosphere microbiome. This study revealed the potential ways and putative keystone taxa of rhizosphere microbiome affecting fruit component production in C. migao, which opens up new opportunities for further manipulation and development of the rhizosphere microbiome to promote plant productivity. [ABSTRACT FROM AUTHOR]

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Drought greatly influences the growth and ecological stoichiometry of plants in arid and semi-arid regions such as karst areas, where Cinnamomum migao (C. migao) is an endemic tree species that is used as a bioenergy resource. Arbuscular mycorrhizal fungi (AMF) play a key role in nutrient uptake in the soil-plant continuum, increasing plant tolerance to drought. However, few studies have examined the contribution of AMF in improving the growth of C. migao seedlings and the soil nutrient stoichiometry under drought-stress conditions. A pot experiment was conducted under natural light in a plastic greenhouse to investigate the effects of individual inoculation and Co-inoculation of AMF [Funneliformis mosseae (F. mosseae) and Claroideoglomus etunicatum (C. etunicatum)] on the growth, water status, and nutrient uptake of C. migao as well as the soil nutrient stoichiometry under well-watered (WW) and drought-stress (DS) conditions. The results showed that compared with non-AMF control (CK), AM symbiosis significantly stimulated plant growth and had higher dry mass. Mycorrhizal plants had better water status than corresponding CK plants. AMF colonization notably increased the total nitrogen and phosphorus content of C. migao seedlings compared with CK. Mycorrhizal plants had higher leaf and stem total carbon concentrations than CK. The results indicated that AM symbiosis protects C. migao seedlings against drought stress by improving growth, water status, and nutrient uptake. In general, the C. migao seedlings that formed with C. etunicatum showed the most beneficial effect on plant growth, water status, and nutrient uptake among all treatments. In the future, we should study more about the biological characteristics of each AMF in the field study to understand more ecological responses of AMF under drought stress, which can better provide meaningful guidance for afforestation projects in karst regions. [ABSTRACT FROM AUTHOR]

Introduction: Rhizobacterial communities and their metabolites can affect plant growth, development, and stress resistance, as well as the biosynthesis and accumulation of bioactive compounds in medicinal plants. This relationship has been well-characterized in many medicinal herbs, although much less commonly in medicinal trees. Methods: Here, we analyzed the composition and structure of Cinnamomum migao rhizobacterial communities across nine growing regions in Yunnan, Guizhou and Guangxi, China, as well as differences in soil properties and fruit bioactive compounds. Results: Results showed that the C. migao rhizobacterial communities exhibited high species richness, but location-specific differences in structure. Site-specific differences in soil properties and bioactive compounds were also observed. Furthermore, rhizobacterial community compositions were correlated with both soil properties and fruit bioactive compounds, metabolism-related functions were most common in C. migao rhizobacteria. Discussion: Several bacterial genera, including Acidothermus, Acidibacter, Bryobacter, Candidatus_Solibacter, and Acidimicrobiales, potentially promote the biosynthesis and accumulation of 1,8-cineole, cypressene, limonene, and α-terpineol, Nitrospira and Alphaproteobacteria may play an inhibitory role. Finally, our results emphasized the critical role that soil pH and nitrogen levels play in driving rhizobacterial community structure, and specific functional bacteria can also counteract with soil properties, Acidibacter and Nitrospira can affect soil pH and nitrogen effectiveness. Overall, this study provides additional insight into the complex correlation of rhizosphere microorganisms with bioactive ingredients and soil properties of medicinal plants. [ABSTRACT FROM AUTHOR]

Cinnamomum migao plants often face different degrees of drought in karst habitats, which can lead to plants’ death, especially in the seedling stage. Widespread of arbuscular mycorrhizal (AM) fungi in karst soils have the potential to address this drought, which is a threat to C. migao seedlings. We inoculated C. migao seedlings with spores from Glomus lamellosum and Glomus etunicatum, two AM fungi widely distributed in karst soils, to observe seedling growth response after simulated drought. Our results showed that 40 g of G. lamellosum and G. etunicatum significantly promoted the growth of C. migao seedlings, 120 days after inoculation. Following a 15-day drought treatment, root colonization of the seedlings with G. lamellosum or G. etunicatum had lower the accumulation of malondialdehyde (MDA) and increased the accumulation of enzymes and osmotic substances in the seedlings. The relative water content in different organs (roots, stems, and leaves) of the drought-stressed seedlings was higher in plants with G. lamellosum or G. etunicatum than in plants without AM fungi colonization. Our results showed that inoculation with AM fungi was an effective means to improve the drought resistance of C. migao seedlings.

Abstract Background This study examined how rhizosphere fungi influence the accumulation of chemical components in fruits of a small population species of Cinnamomum migao. Results Ascomycota and Basidiomycota were dominant in the rhizosphere fungal community of C. migao. Pestalotiopsis and Gibellulopsis were associated with α-Terpineol and sabinene content, and Gibellulopsis was associated with crude fat and carbohydrate content. There were significant differences in rhizosphere fungal populations between watersheds, and there was no obvious change between fruiting periods. Gibberella, Ilyonectria, Micropsalliota, and Geminibasidium promoted sabinene accumulation, and Clitocybula promoted α-Terpineol accumulation. Conclusion The climate-related differentiation of rhizosphere fungal communities in watershed areas is the main driver of the chemical composition of C. migao fruit. The control of the production of biologically active compounds by the rhizosphere fungal community provides new opportunities to increase the industrial and medicinal value of the fruit of C. migao.

【Objective】 The dynamic changes of the fungal community composition in the rhizosphere soil at different development stages of Cinnamomum migao fruit are explored, which provides reference for the utilization of beneficial fungus in the rhizosphere soil of C. migao and the control of harmful microbes. 【Method】 Based on the method of combining morphology and molecular phylogeny analysis, the cultivable rhizosphere fungus of C. migao were isolated and identified. 【Result】 A total of 529 fungi were obtained, which were initially identified as 111 species in 57 genera, 35 families, 3 phyla. At the phylum level, the dominant fungi was Ascomycota; At the family level, the dominant fungi were Hypocreaceae and Phytobacteria; At the genus level, the dominant fungi were Trichoderma and Penicillium. There were some differences in the composition of fungal communities at the three stages. Among them, The fungi isolated and identified at the young fruit stage belonged to 31 genera and 53 species, the dominant genus was Nectria（11.90%）; The fungi isolated and identified at the swelling stage were 36 genera and 64 species, the dominant genus were Trichoderma（16.99%） and Penicillium（16.34%）; The fungi isolated and identified at maturity stage were 16 genera and 31 species, and the dominant genus was Trichoderma（41.90%）. The Shannon diversity index, Simpson index, Margalef index and Pielou index of the rhizosphere cultivable fungal community all showed as the swelling stage﹥ young fruit stage﹥ maturity stage. 【Conclusion】 The rhizosphere soil of C. migao had a rich diversity of cultivable fungi, and it at maturity stage was significantly lower than at the swelling stage and the young fruit stage. The pathogenic fungus Fusarium also had the same changing trend. It was speculated that because the pathogenic antagonist Trichoderma proliferates in large numbers during the fruit ripening stage, the further reproduction of Fusarium was inhibited. [ABSTRACT FROM AUTHOR]

Drought is the main limiting factor for plant growth in karst areas with a fragile ecological environment. Cinnamomum migao H.W. Li is an endemic medicinal woody plant present in the karst areas of southwestern China, and it is endangered due to poor drought tolerance. Arbuscular mycorrhizal fungi (AMF) are known to enhance the drought tolerance of plants. However, few studies have examined the contribution of AMF in improving the drought tolerance of C. migao seedlings. Therefore, we conducted a series of experiments to determine whether a single inoculation and coinoculation of AMF (Claroideoglomus lamellosum and Claroideoglomus etunicatum) enhanced the drought tolerance of C. migao. Furthermore, we compared the effects of single inoculation and coinoculation with different inoculum sizes (20, 40, 60, and 100 g; four replicates per treatment) on mycorrhizal colonization rate, plant growth, photosynthetic parameters, antioxidant enzyme activity, and malondialdehyde (MDA) and osmoregulatory substance contents. The results showed that compared with nonmycorrhizal plants, AMF colonization significantly improved plant growing status; net photosynthetic rate; superoxide dismutase, catalase, and peroxidase activities; and soluble sugar, soluble protein, and proline contents. Furthermore, AMF colonization increased relative water content and reduced MDA content in cells. These combined cumulative effects of AMF symbiosis ultimately enhanced the drought tolerance of seedlings and were closely related to the inoculum size. With an increase in inoculum size, the growth rate and drought tolerance of plants first increased and then decreased. The damage caused by drought stress could be reduced by inoculating 40–60 g of AMF, and the effect of coinoculation was significantly better than that of single inoculation at 60 g of AMF, while the effect was opposite at 40 g of AMF. Additionally, the interaction between AMF and inoculum sizes had a significant effect on drought tolerance. In conclusion, the inoculation of the AMF (Cl. lamellosum and Cl. etunicatum) improved photosynthesis, activated antioxidant enzymes, regulated cell osmotic state, and enhanced the drought tolerance of C. migao, enabling its growth in fragile ecological environments. [ABSTRACT FROM AUTHOR]

The decomposition of litter plays an important role in the return of forest soil nutrients, as well as the growth and productivity of plants. With this study, we aimed to determine the impact of litter mulching on different tissues of Cinnamomum migao, a rare Chinese endemic species. In particular, seeds and pericarp are easily overlooked components of C. migao litter. In this study, we tested control (uncovered litter) and litter (leaf, branch, seed, and pericarp) mulching conditions and conducted a one-year litter decomposition experiment. The enzyme activities of urease enzyme (UE) and invertase enzyme (INV) were significantly improved by litter mulching. Catalase (CAT) enzyme activities in leaf, branch, and seed litter mulching were lower than in the control, whereas CAT activity in pericarp mulching was significantly higher than in the control. Although Mortierella, Cladophialophora, Acidothermus, Sphingomonas, and Burkholderia were the dominant microbes of topsoil in different mulching treatments, there were differences in the number and connectivity of microbial communities, and this change was correlated with soil organic carbon (SOC) and CAT enzyme activity. Compared with leaves and branches, seeds and pericarp as litter are also very important for nutrient return and affect topsoil microbes in C. migao forest, which may be of significance for the growth feedback of C. migao in biennial bearing. [ABSTRACT FROM AUTHOR]

Seed dormancy is a complex adaptive trait of plants that are influenced by several physiological and environmental factors. The endangered plant Cinnamomum migao is also known to exhibit seed dormancy and low germination, which may influence its regeneration; however, these characteristics remain unexplored. To our knowledge, this study is the first to examine the type of dormancy and improve the germination percentage of C. migao seeds. We evaluated the structure and characteristics of the embryo and endocarp of C. migao seeds as well as the effects of endogenous inhibitors. Furthermore, we assessed the effects of light, stratification, alternating temperature, and gibberellic acid 3 (GA3) on the dormancy release of these seeds. The embryo was well developed the endocarp was water-permeable, and no obvious mechanical hindrance to germination was observed. However, the endocarp and embryo contained phenols and other germination inhibitors. The seed extracts of C. migao delayed the germination of cabbage and ryegrass seeds, which indicates the presence of endogenous inhibitors. These findings suggest that C. migao seeds exhibit physiological dormancy. Light and an alternating temperature (15/20°C) did not influence germination. However, GA3 pretreatment, alternating temperatures, and warm stratification relieved dormancy. GA3 pretreatment combined with the 15°C stratification treatment was most effective in rapidly releasing the C. migao seed dormancy. Our findings may facilitate the storage and conservation of this endangered plant, which is currently underrepresented in ex situ collections.

Seed dormancy is a complex adaptive trait of plants that are influenced by several physiological and environmental factors. The endangered plant Cinnamomum migao is also known to exhibit seed dormancy and low germination, which may influence its regeneration; however, these characteristics remain unexplored. To our knowledge, this study is the first to examine the type of dormancy and improve the germination percentage of C. migao seeds. We evaluated the structure and characteristics of the embryo and endocarp of C. migao seeds as well as the effects of endogenous inhibitors. Furthermore, we assessed the effects of light, stratification, alternating temperature, and gibberellic acid 3 (GA3) on the dormancy release of these seeds. The embryo was well developed the endocarp was water-permeable, and no obvious mechanical hindrance to germination was observed. However, the endocarp and embryo contained phenols and other germination inhibitors. The seed extracts of C. migao delayed the germination of cabbage and ryegrass seeds, which indicates the presence of endogenous inhibitors. These findings suggest that C. migao seeds exhibit physiological dormancy. Light and an alternating temperature (15/20°C) did not influence germination. However, GA3 pretreatment, alternating temperatures, and warm stratification relieved dormancy. GA3 pretreatment combined with the 15°C stratification treatment was most effective in rapidly releasing the C. migao seed dormancy. Our findings may facilitate the storage and conservation of this endangered plant, which is currently underrepresented in ex situ collections. [ABSTRACT FROM AUTHOR]

• Three new and one known guaiane-type sesquiterpenoids were isolated from C.migao. • The new compounds were named as (cinmganoid D − F). • Endogenous antioxidant enzymes analysis of these compounds were tested against CAT, SOD, POD, and Nrf-2. • The compounds were evaluated for their anti-inflammatory activities against NO production and pro-inflammatory cytokines. • In silico molecular docking and molecular dynamic simulations studies were also directed. Inflammatory processes are renowned as the fundamental basis for numerous pathological conditions. The objective of this study was to assess the antioxidant, anti-inflammatory, molecular docking, and molecular dynamics simulation properties of 3 previously undescribed and 1 known guaiane-type sesquiterpenoids isolated from Cinnamomum migao. The structures of these compounds were confirmed using numerous chromatographic and spectroscopic methods, such as high-resolution electrospray ionization mass spectrometry (HRESIMS), one-dimensional nuclear magnetic resonance (1D NMR), two-dimensional nuclear magnetic resonance (2D NMR), and experimental circular dichroism (ECD). Additionally, in oxidatively stressed mouse hepatocytes, all tested compounds at a concentration of 50 µM increased the levels of natural antioxidant enzymes such as CAT, SOD, POD, and Nrf-2 compared to those in untreated cells. Compounds 1 and 2 strongly suppressed NO generation and proinflammatory cytokine production, with IC 50 values of 8.76 and 5.45 µM, respectively, against TNF-α mRNA. Furthermore, the molecular docking and simulations explore the high affinity of the selected compounds and best fit in the TNF-α active site. Compounds 1 and 2 show prominent binding energies and bring significant confirmational changes in the TNF-α protein. The results of this study provide further validation for the traditional use of C. migao in the treatment of inflammation and pain, providing novel evidence regarding the therapeutic potential of the identified guaiane-type sesquiterpenoids. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Nitrogen (N) deposition, a major phenomenon of climate change, is increasing with industrialization and more human activity and can affect litter decomposition. Yet it remains unclear whether N deposition will accelerate or inhibit the decomposition of litter in karst regions, which are characterized by P‐limitation or N and P co‐limited stress conditions in soil. Here, to document the influence of simulated N deposition on litter decomposition in karst, the leaf litter of Cinnamomum migao was studied, this being a dominant perennial woody plant endemic to karst landforms. We conducted a 300‐d field decomposition experiment with four treatments: control (CK); addition of (+) N at 50 kg⋅ha−1⋅a−1 (N1); +N at 150 kg⋅ha−1⋅a−1 (N2), and +N at 300 kg⋅ha−1⋅a−1 (N3), in southwest Guizhou, the largest karst region in China (n = 4 treatments). From each treatment, the litter samples’ remaining mass were measured during the decomposition period, in addition to their nitrogen (N), phosphorus (P), carbon (C), and potassium (K) concentrations, as well as that of soils; the soil’s pH was also measured. The results showed that litter remaining mass increased significantly under nitrogen deposition, which, as expected, acidified the soil. Meanwhile, litter N, P, and K contents responded to nitrogen deposition, whereas C did not. Otherwise, no direct effects of nitrogen deposition upon soil nutrients were detected. The soil nutrient contents were related to the release of the elements in litter. In conclusion, nitrogen deposition suppressed the decomposition of C. migao litter in karst, but the nutrients of karst soil are mainly replenished by litter inputs.

Nitrogen (N) deposition, a major phenomenon of climate change, is increasing with industrialization and more human activity and can affect litter decomposition. Yet it remains unclear whether N deposition will accelerate or inhibit the decomposition of litter in karst regions, which are characterized by P‐limitation or N and P co‐limited stress conditions in soil. Here, to document the influence of simulated N deposition on litter decomposition in karst, the leaf litter of Cinnamomum migao was studied, this being a dominant perennial woody plant endemic to karst landforms. We conducted a 300‐d field decomposition experiment with four treatments: control (CK); addition of (+) N at 50 kg⋅ha−1⋅a−1 (N1); +N at 150 kg⋅ha−1⋅a−1 (N2), and +N at 300 kg⋅ha−1⋅a−1 (N3), in southwest Guizhou, the largest karst region in China (n = 4 treatments). From each treatment, the litter samples' remaining mass were measured during the decomposition period, in addition to their nitrogen (N), phosphorus (P), carbon (C), and potassium (K) concentrations, as well as that of soils; the soil's pH was also measured. The results showed that litter remaining mass increased significantly under nitrogen deposition, which, as expected, acidified the soil. Meanwhile, litter N, P, and K contents responded to nitrogen deposition, whereas C did not. Otherwise, no direct effects of nitrogen deposition upon soil nutrients were detected. The soil nutrient contents were related to the release of the elements in litter. In conclusion, nitrogen deposition suppressed the decomposition of C. migao litter in karst, but the nutrients of karst soil are mainly replenished by litter inputs. [ABSTRACT FROM AUTHOR]

Background: This study examined how rhizosphere fungi influence the accumulation of chemical components in fruits of a small population species of Cinnamomum migao. Results: Ascomycota and Basidiomycota were dominant in the rhizosphere fungal community of C. migao. Pestalotiopsis and Gibellulopsis were associated with α-Terpineol and sabinene content, and Gibellulopsis was associated with crude fat and carbohydrate content. There were significant differences in rhizosphere fungal populations between watersheds, and there was no obvious change between fruiting periods. Gibberella, Ilyonectria, Micropsalliota, and Geminibasidium promoted sabinene accumulation, and Clitocybula promoted α-Terpineol accumulation. Conclusion: The climate-related differentiation of rhizosphere fungal communities in watershed areas is the main driver of the chemical composition of C. migao fruit. The control of the production of biologically active compounds by the rhizosphere fungal community provides new opportunities to increase the industrial and medicinal value of the fruit of C. migao. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The decomposition of litter plays an important role in the return of forest soil nutrients, as well as the growth and productivity of plants. With this study, we aimed to determine the impact of litter mulching on different tissues of Cinnamomum migao, a rare Chinese endemic species. In particular, seeds and pericarp are easily overlooked components of C. migao litter. In this study, we tested control (uncovered litter) and litter (leaf, branch, seed, and pericarp) mulching conditions and conducted a one-year litter decomposition experiment. The enzyme activities of urease enzyme (UE) and invertase enzyme (INV) were significantly improved by litter mulching. Catalase (CAT) enzyme activities in leaf, branch, and seed litter mulching were lower than in the control, whereas CAT activity in pericarp mulching was significantly higher than in the control. Although Mortierella, Cladophialophora, Acidothermus, Sphingomonas, and Burkholderia were the dominant microbes of topsoil in different mulching treatments, there were differences in the number and connectivity of microbial communities, and this change was correlated with soil organic carbon (SOC) and CAT enzyme activity. Compared with leaves and branches, seeds and pericarp as litter are also very important for nutrient return and affect topsoil microbes in C. migao forest, which may be of significance for the growth feedback of C. migao in biennial bearing.

Drought stress is one of the greatest obstacles affecting field crop productivity in arid and semi-arid regions, and its severity and frequency are expected to increase due to human-induced changes to the environment and climate. Drought has led to rocky desertification in Karst regions. Cinnamomum migao is a unique, fast-growing medicinal plant of Southwest China that only thrives in Karst regions. Arbuscular mycorrhizal fungi (AMF) symbiosis alleviates drought stress in plants; however, establishment and function of the symbiotic interaction between AMF host plant in relation to the inoculation method remain unclear. Therefore, we conducted an experiment to investigate the effects of AMF species (Glomus etunicatum and Funneliformis mosseae) and two inoculation methods (seed vs. seedling inoculation) under drought stress on C. migao seedlings, and quantified mycorrhizal colonization, AMF spore density, root vigor, relative water content, C. migao growth, antioxidant enzyme activities, and osmotic adjustment. Inoculation with AMF (G. etunicatum and F. mosseae) positively affected the growth and root vigor of Cinnamomum migao under drought stress, regardless of the inoculation method. Additionally, both AMF species markedly upregulated antioxidant enzyme activities and osmotic adjustment substances, regardless of the inoculation method. Our results showed that the collective stimulatory effect of G. etunicatum is more efficient than that of F. mosseae. AMF application could promote afforestation with C. migao to prevent rocky desertification in Karst regions where water is the greatest limiting factor on plant growth and yield.

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Cinnamomum migao H.W.Li(Lauraceae)was used by the people of Miao minority for the treatment of stomach convulsion,vomiting,diarrhoea,dermatophytosis,bellyache,asthma and gastralgia,etc. Methods Essential oil was extracted from this plant by supercritical CO2 fluid extraction(SFE)and steam distillation(SD). The yield of essential oil obtained by SD and SFE was 15.874% and 3.632%,respectively. Results Gas chromatography-mass spectrometry identified 58 compounds in the essential oil,and the major compositions: eucalyptol, a-terpineol, borneol, copaene and camphor. In the comparison, 49 compounds were identified in the essential oil extracted by supercritical CO2, and the major components were copaene,N-ecanoic acid, eucalyptol, spathulenol, β-panasinsene. Conclusion Excellent pharmaceutical activity of the essential oil of C.migao was deteded by our experiments. Investigation found that the essential oil was effective in treating cardiovascular and cerebrovascular diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Drought is a global climatic phenomenon and one of the main factors that negatively affect plant growth. Karst is a unique type of ecosystem where ecological degradation is becoming more and more serious due to the aggravation of global drought. Vegetation restoration is an effective method for preventing ecological degradation in Karst ecosystems. Cinnamomum migao is selected as the tree species for vegetation restoration, because it is a unique, fast-growing medicinal plant of Southwest China that only thrives in Karst regions. Arbuscular mycorrhizal fungi (AMF) are an important component of the soil biota in ecosystems and alleviate drought stress in plants by forming a mutualistic symbiosis. Most previous studies just considered the effects of AMF species on drought resistance but did not evaluate different inoculation methods. The aim of the present study was to compare the effects of different AMF resulting from the use of different inoculation methods on the growth and drought resistance of C. migao seedlings in Karst soil. The findings of this study will improve the success rate of reforestation programs in Karst ecosystems through the utilization of these important microorganisms. Drought stress is one of the greatest obstacles affecting field crop productivity in arid and semi-arid regions, and its severity and frequency are expected to increase due to human-induced changes to the environment and climate. Drought has led to rocky desertification in Karst regions. Cinnamomum migao is a unique, fast-growing medicinal plant of Southwest China that only thrives in Karst regions. Arbuscular mycorrhizal fungi (AMF) symbiosis alleviates drought stress in plants; however, establishment and function of the symbiotic interaction between AMF host plant in relation to the inoculation method remain unclear. Therefore, we conducted an experiment to investigate the effects of AMF species (Glomus etunicatum and Funneliformis mosseae) and two inoculation methods (seed vs. seedling inoculation) under drought stress on C. migao seedlings, and quantified mycorrhizal colonization, AMF spore density, root vigor, relative water content, C. migao growth, antioxidant enzyme activities, and osmotic adjustment. Inoculation with AMF (G. etunicatum and F. mosseae) positively affected the growth and root vigor of Cinnamomum migao under drought stress, regardless of the inoculation method. Additionally, both AMF species markedly upregulated antioxidant enzyme activities and osmotic adjustment substances, regardless of the inoculation method. Our results showed that the collective stimulatory effect of G. etunicatum is more efficient than that of F. mosseae. AMF application could promote afforestation with C. migao to prevent rocky desertification in Karst regions where water is the greatest limiting factor on plant growth and yield. [ABSTRACT FROM AUTHOR]

Autotoxicity is a widespread phenomenon in nature and is considered to be the main factor affecting new natural recruitment of plant populations, which was proven in many natural populations. Cinnamomum migao H. W. Li is an endemic medicinal woody plant species mainly distributed in Southwestern China and is defined as an endangered species by the Red Paper of Endangered Plants in China. The lack of seedlings is considered a key reason for population degeneration; however, no studies were conducted to explain its causes. C. migao contains substances with high allelopathic potential, such as terpenoids, phenolics, and flavonoids, and has strong allelopathic effects on other species. Therefore, we speculate that one of the reasons for C. migao seedling scarcity in the wild is that it exhibits autotoxic allelopathy. In this study, which was performed from the perspective of autotoxicity, we collected leaves, pericarp, seeds, and branches of the same population; we simulated the effects of decomposition and release of litter from these different anatomical parts of C. migao in the field; and we conducted 210-day control experiments on seedling growth, with different concentration gradients, using associated aqueous extracts. The results showed that the leaf aqueous extract (leafAE) significantly inhibited growth indicators and increased damage of the lipid structure of the cell membrane of seedlings, suggesting that autotoxicity from C. migao is a factor restraining seedling growth. The results of the analyses of soil properties showed that, compared with the other treatments, leafAE treatment inhibited soil enzyme activity and also had an impact on soil fungi. Although leafAE could promote soil fertility to some extent, it did not change the effect of autotoxic substances on seedling growth. We conclude that autotoxicity is the main obstacle inhibiting seedling growth and the factor restraining the natural regeneration of C. migao. [ABSTRACT FROM AUTHOR]

We examined allelopathic effects and underlying mechanisms of Cinnamomum migao on its associated species Liquidambar formosana. We assessed effects of aqueous extracts of C. migao pericarp, leaf, and rhizosphere soil at different concentrations on seed germination, seedling growth, and physiology of L. formosana. All extracts inhibited L. formosana seed germination, with obvious inhibition at high concentrations (50 mg mL−1). All extracts promoted the height and ground diameter of seedlings, with the highest promotion achieved with aqueous leaf extract at a concentration of 1 mg mL−1 and aqueous pericarp and rhizosphere soil extracts at a concentration of 5 mg mL−1. All extracts promoted soluble protein accumulation in L. formosana seedlings, with the highest accumulation achieved with aqueous pericarp extracts. Aqueous leaf extract promoted soluble starch accumulation. Aqueous pericarp extract at concentrations of >10 mg mL−1 significantly increased soluble sugar content. Aqueous leaf and rhizosphere soil extracts at concentrations of >5 mg mL−1 increased proline accumulation. All extracts at concentrations of >1 mg mL−1 significantly increased malondialdehyde content. Aqueous pericarp and rhizosphere soil extracts at concentrations of 10 and 0.5 mg mL−1, respectively, promoted superoxide dismutase activity. Activities of soil urease, polyphenol oxidase, and catalase were significantly increased when the concentration of aqueous pericarp and leaf extracts exceeded 5 mg mL−1, and the activity of soil acid phosphatase significantly increased when the concentration of all extracts were 5 mg mL−1. According to the synthetic allelopathic index, the low- and medium-concentration extracts all showed a promoting effect, whereas high concentrations exhibited obvious inhibitory effects; furthermore, the comprehensive effect value of leaf water extraction was higher than that of the pericarp and rhizosphere soil. Thus, allelopathy can affect the long-term co-existence of C. migao and L. formosana. [ABSTRACT FROM AUTHOR]