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The decomposition of litter is susceptible to the influence of climate change and soil conditions, which can subsequently impact the release of carbon dioxide (CO2) from forest soils and the absorption of methane (CH4). Ecological theory proposes the existence of a home-field advantage (HFA) in litter decomposition, suggesting that the decomposition rate of litter (such as fallen leaves, twigs, and roots) may be faster in their native habitat than in foreign environments. Therefore, we selected litter from Pinus tabuliformis (PT) and Quercus acutissima Carruth (QC) in the field and conducted a 439-day litter transplant experiment to test the magnitude and direction of the HFA of these two litter types in three forest stands. During this experiment, we monitored the changes in soil CO2 and CH4 fluxes associated with the decomposition of PT and QC leaf litter in their native and foreign sites. Furthermore, we measured various soil physical, chemical, and biological indicators. The results indicated that the decomposition rate of QC leaf litter was faster in its native habitat, demonstrating a clear HFA effect. Conversely, the decomposition of PT leaf litter was observed to be more rapid in away soil, suggesting a pronounced home-field disadvantage (HFD). The study found that PT leaf litter exhibited greater CO2 release when decomposing in away soil, demonstrating 43 % and 32 % increases compared to bare soil, respectively. Conversely, QC leaf litter was observed to release more CO2 in its home soil. Additionally, the bare soils of the PT and QC home sites were found to absorb more CH4 compared to leaf litter coverage, with increases of 37.8 % and 31.2 %, respectively. The partial least squares model indicated that the litter attributes had a significant direct effect on soil temperature and enzyme activity. Soil temperature and enzyme activity further directly influenced the soil CO2 and CH4 fluxes. The results of our study indicate that the HFA of litter is dependent on litter type, and that litter transplantation can impact soil greenhouse gas exchange. This research provides a theoretical foundation for forest management and conservation strategies, as well as valuable data for global carbon neutrality efforts.
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As global climate change progresses, soil will experience prolonged periods of both drought and heavy rainfall, leading to a more frequent drought-re-wetting process that may impact the ecosystem's carbon (C) cycle. However, understanding the extent to which different water conditions and wet-dry cycles alter the process of soil organic carbon (SOC) mineralization remains limited. Therefore, our study focused on the dammed land unique to the Loess Plateau, silted by check dams constructed for erosion control. We implemented three water gradients-drought (30% WHC), water stress (100% WHC), and wet-dry cycling (30-100%)-indoors to observe the SOC mineralization process five times. We identified a transient excitation effect of the wet-dry cycles on SOC mineralization. Soil mineralization decreased gradually with the alternation of wet-dry cycles. The wet-dry cycles not only significantly impacted the contents of SOC and TN but also stimulated the activities of enzymes related to C and N cycles. As the cycle frequency increased, the utilization of C sources by soil microorganisms gradually decreased, and the dominance of carbohydrates, amines, and acids evolved into a single acid, esters, or alcohols. Phosphatase and Chloroflexi were the main factors influencing SOC mineralization under drought stress, while TN and Ascomycota were the primary factors under water stress. SOC and Gemmatimonadetes were the main limiting factors for SOC mineralization under the wet-dry cycles. Additionally, we quantified the direct and interactive contributions of each factor to SOC mineralization. The direct contributions of drought stress, water stress, and the wet-dry cycles to SOC mineralization were 0.961, 0.736, and 0.942, respectively. This study contributes to a more comprehensive understanding of the mechanisms underlying SOC mineralization in the Loess Plateau under changing conditions.
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Carbono , Suelo , Suelo/química , Sequías , Ecosistema , Cambio Climático , Ciclo del Carbono , AguaRESUMEN
Change of land use have important impacts on ecosystem services (ESs) and human well-being (HWB), yet the trade-off/synergy among land use, ESs, and HWB has still not received sufficient attention at city regional scales level. Weinan City in the southern of the Loess Plateau of China was taken as the study area. Based on ArcGIS, InVEST model, and RUSLE model, the characteristics of spatial and temporal variations of land use and ESs from 2000 to 2020 were analyzed, and the trade-off/synergy relationship between land use, ESs, and HWB was quantified using correlation analysis. The results indicated that the area of cultivated land decreased significantly and the area of built-up land increased significantly from 2000 to 2020 in Weinan City. The grain production, soil conservation, and water yield functions showed an increasing trend, which was a synergistic relationship with HWB. Carbon storage and habitat quality functions showed a decreasing trend, which was a trade-off relationship with HWB. The index value of HWB has increased significantly, mainly in the added value of agricultural and rural per capita income. Land use intensity has a trade-off relationship with GP, WY functions, and HWB. There are many factors that affect this trade-off/synergy relationship, such as land use patterns, economic development, and population growth. The study can provide a theoretical basis for the sustainable development of regional economy and nature.
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Conservación de los Recursos Naturales , Ecosistema , Humanos , Ciudades , Desarrollo Sostenible , Suelo , ChinaRESUMEN
Dexanabinol (HU-211) is an artificially synthesized cannabinoid derivative that exerts neuroprotective effects through anti-inflammatory and antioxidant effects. Curcumin exhibits antidepressant effects in the treatment of major depressive disorder. To investigate the antidepressant effects of solid lipid nanoparticles loaded with both curcumin and dexanabinol, and the underlying mechanisms associated with this combination, we established wild-type (CBR1+/+) and cannabinoid receptor 1 (CBR1) knockout (CBR1-/-) mouse models of major depressive disorder, through the intraperitoneal injection of corticosterone, for 3 successive days, followed by treatment with intraperitoneal injections of solid lipid nanoparticles loading with curcumin (20 mg/kg) and dexanabinol (0.85 mg/kg), for 2 successive days. Our results revealed that solid lipid nanoparticle loading with curcumin and dexanabinol increased the mRNA and protein expression levels of the mature neuronal markers neuronal nuclei, mitogen-activated protein 2, and neuron-specific beta-tubulin III, promoted the release of dopamine and norepinephrine, and increased the mRNA expression of CBR1 and the downstream genes Rasgef1c and Egr1, and simultaneously improved rat locomotor function. However, solid lipid nanoparticles loaded with curcumin and dexanabinol had no antidepressant effects on the CBR1-/- mouse models of major depressive disorder. This study was approved by the Institutional Ethics Committee of Tongji Hospital of Tongji University, China (approval No. 2017-DW-020) on May 24, 2017.
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Objective:To characterize the trends in the incidence and mortality of colorectal cancer in Jing'an District of Shanghai, thus optimizing the prophylactic options for this malignancy. Methods:Data from Shanghai Cancer Registration and Reporting System were used to analyze the colorectal cancer prevalence in Jing'an District from 1993 to 2017. Joinpoint software was used to analyze the trends in the standardized incidence rate and mortality rate by calculating the annual percentage of change (APC) and the average annual percentage of change (AAPC). Results:A total of 13 580 new cases of colorectal cancer were reported in Jing'an District during 1993 and 2017, with an average crude incidence rate of 52.94/105 and a standardized incidence rate of 24.77/105. The total number of deaths was 7 572, with an average crude mortality rate of 29.52/105 and a standardized mortality rate of 12.20/105. The standardized incidence rate of colorectal cancer in Jing'an District from 1993 to 2017 showed an increasing trend (AAPC=1.64%,P<0.001), and the standardized incidence rate of colorectal cancer in both sexes increased (AAPC: 2.10% in men, 1.04% in women). The age-standardized mortality rate (ASMR) did not change significantly. The incidence rate of colorectal cancer increased in men in both age groups of 50 to 74 years and 75 years and older, with an AAPC of 2.07% and 3.32%, respectively. However, this was not evident in women of all age groups. The mortality rate of colorectal cancer in men aged 0-49 years, as well as in men and women at 50-74 age groups, decreased significantly, with an AAPC of -7.46%,-1.13%, and -2.72%, respectively. The mortality rate of colorectal cancer in men of 75 years or older showed no significant trend, while that in women of 75 years or older increased (AAPC=2.30%). Conclusion:The overall standardized incidence rate of colorectal cancer in Jing'an District from 1993 to 2017 was increased, and ASMR did not change significantly. Public health prophylactic options are suggested, including improvement of lifestyle/physical activity and eradication of precancerous lesion polypus in males aged ≥50 years to reduce the incidence of colorectal cancer, and enforcement of second-grade prophylaxis in females aged ≥75 years to decrease the mortality of colorectal cancer.
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Objective:To analyze the long-term trend of viral hepatitis mortality in Jing’an District of Shanghai, and to provide a reference for viral hepatitis prevention and control. Methods:Mortality rate, standard mortality rate, PYLL and potential years of life lost rate (PYLL‰) of viral hepatitis in Jing’an district of Shanghai from 1976 to 2015 were calculated. The annual percent change (APC) of the mortality and PYLL‰ were analyzed by Joinpoint regression analysis. Results:From 1976 to 2015, there were 1 342 viral hepatitis death cases, including 832 males and 510 females. The average crude mortality rate was 8.31/100 000, and the average age-standardized mortality rate was 5.45/100 000. Among the deaths of viral hepatitis, men had a higher mortality rate, age-standardized mortality rate and PYLL% than women (χ2Pearson=107.34, 112.93, 39.15, all P<0.01), men were mainly in the age group of 35-64 years (accounted for 62.62%), while women were mainly in the age group of 65 years and above (accounted for 55.49 %), and the average death age of men was earlier than that of women (by rank-sum test: Z=-8.879,P<0.01). After 1990 (except in 2002), hepatitis B was the main cause of deaths from viral hepatitis, accounting for 75.00%-100%, and the proportion of other and unclassified cases gradually decreased. Overall, the mortality rate of viral hepatitis declined significantly during 1976-2015 (APC=-2.0%,P<0.05), with the turning point in 2002. The mortality rate of viral hepatitis declined significantly from 2002 to 2015 (APC=-8.1%,P<0.05). The overall PYLL‰ of viral hepatitis declined significantly during 1976-2015 (APC=-3.7%,P<0.05), with the turning point in 1992. After 1992, the PYLL‰ of viral hepatitis declined significantly during 1992-2015 (APC=-6.5%,P<0.05). Conclusion:There has been a significant decline trend of viral hepatitis in the mortality rate in Jing’an District of Shanghai from 2002 to 2015, with hepatitis B as the main cause of death.
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BACKGROUND: We aimed to determine the safety and effectiveness of laparoscopic-assisted surgery (LAS) in visceral obesity patients with colorectal cancer (CRC). PATIENTS AND METHODS: We retrospectively collected the clinical data of consecutive patients who underwent colorectal surgery for CRC between August 2014 and July 2018. The third lumbar vertebra visceral fat area was measured to diagnose visceral obesity. One-to-one propensity score matching was performed to compare the short-term outcomes between the open surgery (OS) and LAS in visceral obesity patients. Univariate and multivariate analyses were performed to evaluate the risk factors of postoperative complications. RESULTS: A total of 280 visceral obesity patients were included in this study with 140 patients for each group. Compared with the OS group, the LAS group had more lymph nodes harvested, longer surgical duration, and shorter postoperative hospital stay. The overall incidence of complications in OS was significantly higher than LAS (32.1 vs. 20.0%, P=0.021). Multivariate analysis revealed that age of at least 65 years (odds ratio: 1.950, 95% confidence interval: 1.118-3.403; P=0.019) was an independent risk factor for postoperative complications, whereas LAS (odds ratio: 0.523, 95% confidence interval: 0.302-0.908; P=0.021) was a protective factor. CONCLUSION: LAS in visceral obesity patients with CRC was a safer and less invasive alternative than open surgery, with fewer complications within the first 30 days postoperatively.
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Colectomía/métodos , Neoplasias Colorrectales/cirugía , Laparoscopía/métodos , Obesidad Abdominal/complicaciones , Complicaciones Posoperatorias/epidemiología , Proctectomía/métodos , Absceso Abdominal/epidemiología , Anciano , Fuga Anastomótica/epidemiología , Neoplasias Colorrectales/complicaciones , Conversión a Cirugía Abierta , Femenino , Humanos , Laparotomía , Tiempo de Internación/estadística & datos numéricos , Enfermedades Pulmonares/epidemiología , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Tempo Operativo , Puntaje de Propensión , Estudios Retrospectivos , Infección de la Herida Quirúrgica/epidemiologíaRESUMEN
The sediment-reducing effect of check dams and the safety issues following dam breaks are long-standing concerns. This study analyzed the runoff change and sediment source during rainstorms in a small watershed using a multivariate mixed model and a comparative analysis of watersheds. The problem of sediment loss from dammed farmland following check dam break during rainstorms was evaluated. The results showed that the flood peak lag time (PLT) was significantly influenced by pre-soil moisture in cases of small amounts of rainfall but not during rainstorms. Ecological construction significantly reduced the linear correlation between rainfall and runoff modulus (RM). The reduction in sediment delivery modulus (SDM) due to the check dam was more significant than that in RM. The reduction in RM and SDM under rainstorm conditions were 16%-74% and 53%-93%, respectively. The contributions of inter-gully and gully lands to the sediment deposited in dammed farmland during a large rainstorm on July 26, 2017 were 38.07% and 61.93%, respectively. Soil erosion remained significant during large rainstorms. The increase in vegetation coverage on the hill slope increased the amount of sediment from gully lands. Check dam breaches have accounted for a loss of only 1.2% of the total area of the dammed farmland, and thus have not caused a large loss of sediment. However, breaches in them clearly increased the coefficient of variation of RM and SDM. Therefore, check dams have a critical effect on controlling sediment delivery at the watershed scale. Dam breaks do not result in a large percentage of sediment loss in the dammed farmland.
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The seasonal freeze-thaw process affects soil water migration, which influence spring planting, especially in arid and semi-arid regions that cannot be irrigated on the Loess Plateau. This study was conducted to evaluate differences in the freeze-thaw process and water migration between dam farmland (DF) and slope farmland (SF). To accomplish this, two typical agricultural soils (DF and SF), soil water content (SWC) and soil temperature (ST) were monitored at different depths (15, 30, 60 and 90â¯cm), were investigated under freeze-thaw conditions from November 2015 to April 2016 in the Northwest China. The results showed that different freeze-thaw process between dam farmland (DF) and slope farmland (SF). The DF can keep soil water content resulting from longer frozen period. Thermal transmission between soil and air in SF is greater than that in DF. The SWC values in DF were higher than in SF at each depth layer under similar soil temperature. Migrated and incremental SWC in the DF is greater than that in SF during the freeze-thaw process. The initial SWC is the main impact on freeze-thaw process in this study. This research can provide useful information to guide the water management of seasonally frozen agricultural soil.
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Plant roots are a highly heterogeneous and hierarchical system. Although the root-order method is superior to the root diameter method for revealing differences in the morphology and physiology of fine roots, its complex partitioning limits its application. Whether root order can be determined by partitioning the main root based on its diameter remains uncertain. Four methods were employed for studying the morphological characteristics of seedling roots of two Pinus species in a natural and nitrogen-enriched environment. The intrinsic relationships among categories of roots by root order and diameter were systematically compared to explore the possibility of using the latter to describe root morphology. The normal transformation method proved superior to the other three in that the diameter intervals corresponded most closely (at least 68.3%) to the morphological characteristics. The applied methods clearly distinguished the results from the natural and nitrogen-rich environments. Considering both root diameter and order simplified the classification of fine roots, and improved the estimation of root lifespan and the data integrity of field collection, but failed to partition all roots into uniform diameter intervals.
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Biología Computacional/métodos , Raíces de Plantas/anatomía & histología , Raíces de Plantas/clasificación , Pinus/anatomía & histología , Pinus/clasificaciónRESUMEN
The influence of elevated CO2 and nitrogen (N) addition on soil microbial communities and the rhizospheric effects of Bothriochloa ischaemum were investigated. A pot-cultivation experiment was conducted in climate-controlled chambers under two levels of CO2 (400 and 800 µmol mol-1) and three levels of N addition (0, 2.5, and 5 g N m-2 y-1). Soil samples (rhizospheric and bulk soil) were collected for the assessment of soil organic carbon (SOC), total N (TN), total phosphorus (TP), basal respiration (BR), and phospholipid fatty acids (PLFAs) 106 days after treatments were conducted. Elevated CO2 significantly increased total and fungal PLFAs in the rhizosphere when combined with N addition, and N addition significantly increased BR in the rhizosphere and total, bacterial, fungal, Gram-positive (G+), and Gram-negative (G-) PLFAs in both rhizospheric and bulk soil. BR and total, bacterial, G+, and G+/G- PLFAs were significantly higher in rhizospheric than bulk soil, but neither elevated CO2 nor N addition affected the positive rhizospheric effects on bacterial, G+, or G+/G- PLFAs. N addition had a greater effect on soil microbial communities than elevated CO2, and elevated CO2 and N addition had minor contributions to the changes in the magnitude of the rhizospheric effects in B. ischaemum.
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Biota , Dióxido de Carbono/metabolismo , Nitrógeno/metabolismo , Poaceae/metabolismo , Poaceae/microbiología , Rizosfera , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Carbono/química , Hongos/clasificación , Hongos/genética , Fosfolípidos/análisis , Fósforo/análisis , Suelo/químicaRESUMEN
Water shortage in the arid-semiarid regions of China seriously hampers ecosystem construction. Therefore, elucidation of the mechanisms by which vegetation in that area responds to drought stress may enable us to improve utilization of limited water resources and thus contend with the problem of drought and water shortage. We studied Bothriochloa ischaemum, a native grass species, conducted potting control tests to compare several indicators of B. ischaemum grown under three different moisture conditions (80%, 60%, 40% Field capacity represent sufficient water supply, mild water stress, and serious water stress, respectively). Plant response parameters measured included biomass accumulation, root morphology, transient water use efficiency (WUE), stable carbon isotope ratio (δ13C), and stable carbon isotope discrimination (Δ13C) of various plant organs and their interrelationships. B. ischaemum had the greatest WUE under mild drought stress. However, serious drought stress resulted in considerable decline in overall biomass but substantial increase in root-to-shoot ratio and fine-root biomass. Coarse-root biomass dropped appreciably, indicating that serious drought stress leads to allocation non-uniformity of the carbon "sink." δ13C and Δ13C of stem correlated considerably with root morphology, suggesting the feasibility of characterizing WUE, biomass, and root morphology of B. ischaemum via the stable carbon isotope approach. Our evaluation of 21 drought resistance indicators of B. ischaemum showed that under a given moisture treatment gradient one can isolate an optimal indicator to express growth, morphology, and physiology, to improve the accuracy of depicting plant drought resistance and simplify the drought resistance indicator system. This study elucidates the response mechanism of B. ischaemum to drought stress and provides theoretical support to screening of drought-resistant plants across the arid-semiarid regions of China.
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A water control pot experiment was conducted in climate controlled chambers to study soil carbon, nitrogen and microbial community structure and their rhizosphere effects in the rhizosphere and non rhizosphere soil of Bothriochloa ischaemum at elevated CO2 concentrations (800 µmol·mol-1) under three water regimes, i.e., well watered (75%-80% of field capacity, FC), moderate drought stress (55%-60% of FC), and severe drought stress (35%-40% of FC). The results showed that elevated CO2 concentration and drought stress did not have significant impacts on the content of soil organic carbon, total nitrogen or dissolved organic carbon (DOC) in the rhizosphere and bulk soils or their rhizosphere effects. Elevated CO2 concentration significantly decreased dissolved organic nitrogen (DON) content in the rhizosphere soil under moderate drought stress, increased DOC/DON, and significantly increased the negative rhizosphere effect of DON and positive rhizosphere effect of DOC/DON. Drought stress and elevated CO2 concentration did not have significant impacts on the rhizosphere effect of total and bacterial phospholipid fatty acids (PLFA). Drought stress under elevated CO2 concentration significantly increased the G+/G- PLFA in the rhizosphere soil and decreased the G+/G- PLFA in the bulk soil, so its rhizosphere effect significantly increased, indicating that the soil microbial community changed from chemoautotroph microbes to heterotrophic microbes.
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Dióxido de Carbono , Sequías , Rizosfera , Carbono , Nitrógeno , Suelo , Microbiología del SueloRESUMEN
A pot experiment was conducted to study soil dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in the rhizosphere and non-rhizosphere of Bothriochloa ischaemum in loess hilly-gully region under the different treatments of CO2 concentrations (400 and 800 µmol·mol-1) and nitrogen addition (0, 2.5, 5.0 g N·m-2·a-1). The results showed that eleva-ted CO2 treatments had no significant effect on the contents of DOC, dissolved total nitrogen (DTN), DON, dissolved ammonium nitrogen (NH4+-N) and dissolved nitrate nitrogen (NO3--N) in the soil of rhizosphere and non-rhizosphere of B. ischaemum. The contents of DTN, DON, and NO3--N in the rhizosphere soil were significantly increased with the nitrogen application and the similar results of DTN and NO3--N also were observed in the non-rhizosphere of B. ischaemum. Nitrogen application significantly decreased DOC/DON in the rhizosphere of B. ischaemum. The contents of DTN, NO3--N and DON in the soil of rhizosphere were significantly lower than that in the non-rhizosphere soil, and DOC/DON was significantly higher in the rhizosphere soil than that in the non-rhizosphere soil. It indicated that short-term elevated CO2 concentration had no significant influence on the contents of soil dissolved organic carbon and nitrogen. Simulated nitrogen deposition, to some extent, increased the content of soil dissolved nitrogen, but it was still insufficient to meet the demand of dissolved nitrogen for plant growing.
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Dióxido de Carbono , Nitrógeno , Suelo , Carbono , RizosferaRESUMEN
OBJECTIVES: To explore the characteristics and prognostic factors associated with the death of systemic lupus erythematosus (SLE) with sepsis in intensive care unit(ICU). METHODS: Clinical and laboratory documents of SLE patients with sepsis from Jan 2010 to Dec 2014 were retrospectively analyzed, including active organ involvement, systemic lupus erythematosus disease activity index (SLEDAI) score, acute physiology and chronic health evaluation (APACHE) Ⅱ score, sites of infection and organisms cultured. Prognostic factors were analyzed by multivariate logistic regression analysis. RESULTS: Included patients were mainly females (86%, 43/50). For all patients, SLEDAI was 15.8±6.3; APACHE Ⅱ was 25.8±6.5; the mortality rate during ICU hospitalization was 46%. The most common causes of death and admission were multiple organ dysfunction syndrome and respiratory failure, respectively. The most common pathogen was Gram-negative bacteria.Multivariate logistic regression analysis suggested that gastrointestinal bleeding, septic shock and high APACHE Ⅱ score were independent risks for mortality. CONCLUSIONS: Gastrointestinal bleeding, septic shock and high APACHE Ⅱ score were risk factors in SLE patients with sepsis in ICU.
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Lupus Eritematoso Sistémico/diagnóstico , Sepsis/complicaciones , APACHE , Antracenos , Femenino , Hemorragia Gastrointestinal/complicaciones , Humanos , Unidades de Cuidados Intensivos , Lupus Eritematoso Sistémico/complicaciones , Masculino , Pronóstico , Estudios Retrospectivos , Choque Séptico/complicacionesRESUMEN
Chinese medicinal plants and their surrounding rhizospheric soil serve as promising sources of actinobacteria. A total of 180 actinobacteria strains were isolated from the rhizosphere soil, leaves, stems, and roots of nine selected plants and have been identified as potential biocontrol agents against Fusarium oxysporum f. sp. cucumerinum. An endophytic strain CNS-42 isolated from Alisma orientale showed the largest zone of inhibition demonstrating a potent effect against F. oxysporum f. sp. cucumerinum and a broad antimicrobial activity against bacteria, yeasts, and other pathogenic fungi. The in vivo biocontrol assays showed that the disease severity index was significantly reduced (P < 0.05), and plant shoot fresh weight and height increased greatly (P < 0.05) in plantlets treated with strain CNS-42 compared to the negative control. This isolate was identified as Streptomyces sp. based on cultural, physiological, morphological characteristics, and 16S rRNA gene analysis. Further bioassay-guided isolation and purification revealed that staurosporine was responsible for its antifungal and plant growth promoting activities and the latter property of staurosporine is reported for the first time. The in vivo assay was further performed and indicated that staurosporine showed good growth promoting effect on the plant shoot biomass of cucumber. This is the first critical evidence identifying CNS-42 as a biocontrol agent for the soil borne pathogen, F. oxysporum f. sp. cucumerinum.