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Response of photosynthesis,growth,and acorn mass of pedunculate oak to diff erent levels of nitrogen in wet and dry growing seasons 被引量:1
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作者 Krunoslav Sever Saša Bogdan ŽeljkoŠkvorc 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期167-176,共10页
The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn ma... The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of pedunculate oak during 2010 in the absence of drought stress and during 2011 under the impact of moderate drought stress.According to the results,moderate drought stress significantly reduced net photo synthetic rate,stem diameter increment and height growth increment,while acorn mass was not affected.Suboptimal nitrogen nutrition significantly reduced the net photo synthetic rate and stem diameter increment only in the wet year,acorn mass in both wet and dry years,while height growth increment was not significantly reduced by suboptimal nitrogen nutrition in either year.The results indicate that optimal nitrogen levels can stimulate photo synthetic rate and stem diameter increment of pedunculate oak only in the absence of moderate drought stress.Moreover,the results show that moderate drought stress is a more dominant stressor for photosynthesis and growth of pedunculate oak than suboptimal nitrogen nutrition,while for acorn development,it is the more dominant stressor. 展开更多
关键词 Quercus robur L. Drought stress Net photosynthic rate Stem diameter increment Height growth increment Acorn mass
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Endophytic Bacteria Promote the Growth of Suaeda glauca in Saline-Alkali Stress:Regulation of Osmotic Pressure and Antioxidative Defense System
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作者 FENG Kanghong SUN Ping +1 位作者 CHEN Youyuan GUO Jiameng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1109-1118,共10页
Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of en... Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment.For ecological remediation of coastal wetlands,it was necessary to investigate the effect and interaction of endophytes on halophytes under saline-alkali stress.In this study,an endophytic bacterium strain HK1 isolated from halophytes was selected to infect Suaeda glauca under pH(7 and 8)and salinity gradient(150,300 and 450mmolL^(-1)).Strain HK1 was identified as Pantoea ananatis and it had ability to fix nitrogen,dissolve inorganic phosphorus and produce indole-3-aceticacid(IAA).The results showed that strain HK1 could promote the growth of S.glauca seedings when the salinity was less than 300mmolL^(-1),in view of longer shoot length and heavier fresh weight.The infected plants could produce more proline to decrease the permeability of cells,which content increased by 26.2%–61.1%compared to the non-infected group.Moreover,the oxidative stress of infected plants was relieved with the malondialdehyde(MDA)content decreased by 16.8%–32.9%,and the peroxidase(POD)activity and catalase(CAT)activity increased by 100%–500%and 6.2%–71.4%,respectively.Statistical analysis revealed that increasing proline content and enhancing CAT and POD activities were the main pathways to alleviate saline-alkali stress by strain HK1 infection,and the latter might be more important.This study illustrated that endophytic bacteria could promote the growth of halophytes by regulation of osmotic substances and strengthening antioxidant activities.This finding would be helpful for the bioremediation of coastal soil. 展开更多
关键词 endophytic bacteria Suaeda glauca plant growth promotion plant-microorganism interaction antioxidant enzyme
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Studies on the Isolation of Endophytic Bacteria from Tomato Plants and Their Growth-promoting Activities 被引量:10
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作者 张立新 宋江华 刘慧平 《Agricultural Science & Technology》 CAS 2008年第5期1-3,69,共4页
[Objective] The study aimed to investigate the growth-promoting activities of endophytic bacteria from tomato plants.[Method]The endophytic bacteria isolated from different tissues of tomato plants were analyzed for t... [Objective] The study aimed to investigate the growth-promoting activities of endophytic bacteria from tomato plants.[Method]The endophytic bacteria isolated from different tissues of tomato plants were analyzed for the effects of their growth-promoting activities on the germination and growth of tomato plants.The bacteria with growth-promoting activity were preliminarily identified.[Result]Totally 59 endophytic bacterial strains were isolated from roots and stems of tomatoes,of which 4 showed significantly growth-promoting activity to germination and growth of tomato.The results suggest that these strains are endowed with the potential capability of growth-promoting.[Conclusion]The endophytic bacteria with growth-promoting activity were found among the isolates from tomato plants.This provided a good foundation for utilization of these bacteria with growth-promoting activity. 展开更多
关键词 TOMATO ENDOPHYTIC bacteria ISOLATION growth-PROMOTING activity
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Determination of Growth-promoting and Antagonistic Action of Endophytic Bacteria Strains Itb57 and Itb295 of Tobacco 被引量:1
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作者 汪莹 李小松 +1 位作者 胡建新 马冠华 《Plant Diseases and Pests》 CAS 2011年第1期46-48,共3页
[ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promo... [ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promoting effects of bacterial suspension ~ff endophytic bacteria Itb57 and Itb295 on tobacco seedling un- der different treatment modes were studied using potting method in greenhouse. The antagonistic action of bacterial suspension of endophytic bacteria Itb57 and Itb295 on Phytophthora nicotianae, Alternaria alternata and Botrytis cinerea were measured by duel culture method. [ Result] Bacterial suspensions of enduphytic bacteria Itb57 and Itb295 had certain growth-promoting effects on tobacco seedling, which could significantly increase the fresh weight and dry weight in aerial part; the growth-promoting effect of soaking + spraying and irrigating treatment was the best. Itb57 strain had good antagonistic action against P. nicotianae. A. alterna- ta and B. cinerea, while Itb295 strain only had good antifungal effect against P. nicotianae. [ Conclusion] The results provided basis for the study and application of tobacco endophytic bacteria strains Itb57 and Itb295 in biocontrol of tobacco diseases. 展开更多
关键词 TOBACCO Endophytic bacteria growth-promoting effect Antagonistic activity
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Endophytic bacteria associated with endangered plant Ferula sinkiangensis K. M. Shen in an arid land: diversity and plant growth-promoting traits 被引量:6
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作者 LIU Yonghong GUO Jianwei +5 位作者 LI Li Mipeshwaree D ASEM ZHANG Yongguang Osama A MOHAMAD Nimaichand SALAM LI Wenjun 《Journal of Arid Land》 SCIE CSCD 2017年第3期432-445,共14页
Ferula spp. are traditional medicinal plants found in arid land. Large-scale excavation for extracting bioactive compounds from the plants in arid regions of Xinjiang over the last few years has, however, significandy... Ferula spp. are traditional medicinal plants found in arid land. Large-scale excavation for extracting bioactive compounds from the plants in arid regions of Xinjiang over the last few years has, however, significandy decreased their distributions. Due to the urgent need for preservation of these plant resources, along with the need of searching for alternative source of the useful metabolites, it is important to screen the endophytic microbial resources associated with the plant Ferula sinkiangensis K. M. Shen. In the study, a total of 125 endophytic bacteria belonging to 3 phyla, 13 orders, 23 families, and 29 genera were isolated based on 16S rRNA gene sequencing data. Among the different isolates, three strains isolated from roots were potential novel species of the genera Porphyrobacter, Paracoccus and draycofatopsis. In this study, 79.4% and 57.1% of the total isolates were capable of producing indole-3-acetic acid (IAA) and siderophore, respectively. And, 40.6% of the strains inhibit the growth of fungal pathogen Afternaria alternata, 17.2% and 20.2% strains were positive for antagonism against Vertidllium dahlia 991 and V. dahlia 7, respectively. These results demonstrated that E sinkiangensis is a rich reservoir of endophytic bacterial resources with potential for production of biologically important functions such as plant growth-promoting factors. 展开更多
关键词 endophytic bacteria Ferula sinkiangensis endangered species growth promoting
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Effects of recombinant human growth hormone on intestinal translocation of bacteria and endotoxin in rats with obstructive jaundice 被引量:7
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《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第3期445-449,共5页
Extrahepatic biliary obstruction promotes intestinal translocation of bacteria and endotoxin and this process is an important cause of morbidity and mortality in patients with jaundice. This study was undertaken to in... Extrahepatic biliary obstruction promotes intestinal translocation of bacteria and endotoxin and this process is an important cause of morbidity and mortality in patients with jaundice. This study was undertaken to investigate the effect and mechanism of recombinant human growth hormone (rhGH) and to alleviate intestinal translocation of bacteria and endotoxin in murine obstructive jaundice. METHODS:A group of 42 Wistar rats were divided into 3 groups:sham operation (SO), bile duct ligation (BDL), and BDL and rhGH treatment (rhGH). By the end of the experiment,on day 7, the animals were killed, and their liver function and serum endotoxin were measured, bacterial cultures of the liver, kidney and mesenchymal lymph were made. Terminal ileum mucosa was observed under an electron microscope. RESULTS:Liver function was improved more significantly in the rhGH group than in the BDL group. The value of endotoxin in the rhGH group was 0.38±0.03 EU/ml, significantly lower than that in the BDL group (0.65±0.04 EU/ml, P【0.01), and similar to that in the SO group (0.30±0.02 EU/ml, P】0.05). The rate of bacteria translocation in the liver, kidney and mesenteric lymph was much higher in the BDL group than in other two groups. The rate of bacteria translocation in mesenteric lymph was 64.29%,significantly higher than that in the SO group and the rhGH group (P【0.05). There was no significant difference in bacteria translocation rate between the SO group and the rhGH group (P】0.05). Under an electron microscope , ileum mucosa epithelial cells in the BDL group were necrotic, and organelle were markedly metamorphic. In the rhGH group, ultrastructural changes were less evident or similar to those in the SO group. CONCLUSION:rhGH has significant protective effects on intestinal mucosa barrier in obstructive jaundice, and reduces intestinal translocation of bacteria and endotoxin. 展开更多
关键词 OBSTRUCTIVE JAUNDICE bacteria TRANSLOCATION ENDOTOXIN TRANSLOCATION recombinant human growth HORMONE
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Growth of marine bacteria and ammonium regeneration from substrates in different C:N ratios 被引量:2
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作者 WANG Jiangtao YIN Xiaonan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第3期59-64,共6页
Natural assemblages of marine bacteria were chosen in a batch culture experiments. The impact of varying nitrogen substrate concentrations and the substrate C:N ratios (C:Ns) on the bacterial C:N ratio (C:NB),... Natural assemblages of marine bacteria were chosen in a batch culture experiments. The impact of varying nitrogen substrate concentrations and the substrate C:N ratios (C:Ns) on the bacterial C:N ratio (C:NB), the bacterial growth efficiency (BGE) and ammonium regeneration was mainly examined. The C:Ns ratios varied from 5:1 (carbon limitation) to 40:1 (nitrogen limitation) with varying combinations of glucose and NO3. The C:NB ratio had positive relationship with the C:Ns ratio (r=0.93, n=8), whose value was 3.77 when the C:Ns ratio was 5:1 but increased to 6.47 when the C:Ns ratio was 40:1. These results indicate that the C:NB ratio is a potential diagnostic tool for determining the bacterial growth in natural waters controlled by either, carbon or nitrogen. BGE decreased with the declining nitrate concentration and negatively related to C:N8 (r=-0.51, n=8). The average value of BGE was 0.20. This value was a little lower than other reports, which could be induced by the nitrogen source used in our experiments. Finally, regeneration time of ammonium delayed with the increasing C:Ns ratio, which indicates that there were different metabolism mechanisms when bacterial growth was limited by carbon source and nitrogen source. 展开更多
关键词 marine bacteria C:N bacteria growth efficiency AMMONIUM
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Selection,Identification and Growth Promotion of Inorganic Phosphorus-dissolving Bacterial Strains in Rhizosphere of Trifolium repens
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作者 刘晓霞 陆瑞霞 +2 位作者 王小利 李显刚 姚拓 《Agricultural Science & Technology》 CAS 2012年第10期2058-2064,共7页
[Objective] The aim was to select and identify inorganic phosphorus-dissolving bacteria in rhizosphere of Trifolium repens,and to research related effects of growth promotion.[Method] Phosphate solubilizing bacteria i... [Objective] The aim was to select and identify inorganic phosphorus-dissolving bacteria in rhizosphere of Trifolium repens,and to research related effects of growth promotion.[Method] Phosphate solubilizing bacteria in rhizosphere of Trifolium repens in Guizhou Province were separated and selected to determine its ability of phosphate solubilizing and IAA secretion,and growth promotion effect.[Result] Phosphate solubilizing bacteria were multiple and varied in rhizosphere of Trifolium repens;solubilizing quantities of phosphorus from calcium phosphate by RW2,RW6 and RW18 were 337.39,447.45 and 462.03 μg/ml;solubilizing quantity was none of linear relation with organic acid;RW2 proved the one secreted most IAA at 12.69 μg/ml,followed by RW18 at 12.34 μg/ml;the three strains were all of Leclercia sp.,but were of none pathogenicity for seedlings of Trifolium repens,instead,a kind of growth promotion was found.Detailedly,RW18 was most effective in growth promotion for Trifolium repens and plant height,root length and weight,and aboveground biomass increased by 110.98%,9.17%,46.17% and 2% respectively.Hence,RW18 is of great potential.[Conclusion] The research provides scientific references for developing phosphate solubilizing bacteria and compound inoculation and develops a novel way to relieve barren soils,save phosphorus resource,reduce environment pollution,and guarantee sustainable development of agriculture and animal husbandry. 展开更多
关键词 Trifolium repens Phosphate solubilizing bacteria growth promotion 16S rDNA
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A Model for the Mass-Growth of Wild-Caught Fish 被引量:1
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作者 Katharina Renner-Martin Norbert Brunner +2 位作者 Manfred Kühleitner Werner-Georg Nowak Klaus Scheicher 《Open Journal of Modelling and Simulation》 2019年第1期19-40,共22页
The paper searched for raw data about wild-caught fish, where a sigmoidal growth function described the mass growth significantly better than non-sigmoidal functions. Specifically, von Bertalanffy’s sigmoidal growth ... The paper searched for raw data about wild-caught fish, where a sigmoidal growth function described the mass growth significantly better than non-sigmoidal functions. Specifically, von Bertalanffy’s sigmoidal growth function (metabolic exponent-pair a = 2/3, b = 1) was compared with unbounded linear growth and with bounded exponential growth using the Akaike information criterion. Thereby the maximum likelihood fits were compared, assuming a lognormal distribution of mass (i.e. a higher variance for heavier animals). Starting from 70+ size-at-age data, the paper focused on 15 data coming from large datasets. Of them, six data with 400 - 20,000 data-points were suitable for sigmoidal growth modeling. For these, a custom-made optimization tool identified the best fitting growth function from the general von Bertalanffy-Pütter class of models. This class generalizes the well-known models of Verhulst (logistic growth), Gompertz and von Bertalanffy. Whereas the best-fitting models varied widely, their exponent-pairs displayed a remarkable pattern, as their difference was close to 1/3 (example: von Bertalanffy exponent-pair). This defined a new class of models, for which the paper provided a biological motivation that relates growth to food consumption. 展开更多
关键词 growth Models Described by the von Bertalanffy-Pütter Differential Equation MODEL Selection USING the Akaike Information Criterion Maximum LIKELIHOOD Fit Based on a LOGNORMAL Distribution of mass Optimization USING Simulated Annealing
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Identification of Growth-promoting Bacteria from Rhizosphere of Pastures and Their Effects on Growth of Lotus corniculatus L. 被引量:1
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作者 Lu CAI Yajiao LI +2 位作者 Xiaoxia LIU Xin WEI Jianhong SHU 《Agricultural Biotechnology》 CAS 2019年第5期106-111,共6页
[Objectives] This study was conducted to explore the interaction between nitrogen-fixing and phosphate-solubilizing strains and the optimal combination of different functional strains,in order to provide a theoretical... [Objectives] This study was conducted to explore the interaction between nitrogen-fixing and phosphate-solubilizing strains and the optimal combination of different functional strains,in order to provide a theoretical basis for the development of PGPR compound fertilizers suitable for local environment.[Methods] In this study,16S rDNA gene sequence analysis was used to identify fast-growing and competitive strains from pasture nodules and rhizosphere soils in Guizhou Province,and three representative Rhizobia and phosphorus-solubilizing bacteria were chosen for the test of bacterial combination when reducing 50% of nitrogen and 30% of phosphorus.The effects of different strain combinations on the plant height,root length,aboveground and underground biomass of Lotus corniculatus L.were investigated,and the total nitrogen and total phosphorus contents of the plants were determined.[Results] The mixed bacterial agents could promote the increase of root biomass,and the effects of A1,A3,B3 and C3 were the most obvious.The fresh weight and dry weight of the roots of L.corniculatus increased by 30.35%-168.45% and 26.43%-180.00%,respectively,and A3,B3,B2 and C3 had the best effects.The total phosphorus content of the plants increased by 12.79%-55.25% compared with the CK2;and most of the bacterial agents with significant growth-promoting effects showed decreased total nitrogen contents,while those with non-significant growth-promoting effects showed significantly-increased total nitrogen contents,which were not as much as the CK1.Comprehensively,the most productive combination was C3,namely R27-2 Rhinohizobium fredii and P33-3 Stenotrophomonas rhizophila.[Conclusions] This study can provide a theoretical basis for the production and promotion of bacterial fertilizers. 展开更多
关键词 growth-PROMOTING bacteria LOTUS corniculatus L. BIOmass Quality
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Weak coupling between heterotrophic nanoflagellates and bacteria in the Yellow Sea Cold Water Mass area
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作者 LIN Shiquan HUANG Lingfeng LU Jiachang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第9期125-132,共8页
A study was carried out to investigate the grazing pressure of heterotrophic nanoflagellates (HNF) on bac-teria assemblages in the Yellow Sea Cold Water Mass (YSCWM) area in October, 2006. The results show that th... A study was carried out to investigate the grazing pressure of heterotrophic nanoflagellates (HNF) on bac-teria assemblages in the Yellow Sea Cold Water Mass (YSCWM) area in October, 2006. The results show that the HNF abundance ranges from 303 to 1388 mL-1, with a mean of 884 mL-1. The HNF biomass is equivalent to 10.6%-115.6% of that of the bacteria. The maximum abundance of the HNF generally occurred in the upper 30 m water layer, with a vertical distribution pattern of surface layer abundance greater than middle layer abundance, then bottom layer abundance. The hydrological data show that the YSCWM is located in the northeastern part of the study area, typically 40 m beneath the surface. A weak correlation is found be- tween the abundances of HNF and bacteria in both the YSCWM and its above water layer. One-way ANOVA analysis reveals that the abundance of HNF and bacteria differs between inside the YSCWM and in the above water mass. The ingestion rates of the HNF on bacteria was 8.02±3.43 h-1 in average. The grazing rate only represented 22.75%±6.91% of bacterial biomass or 6.55%±4.24% of bacterial production, implying that the HNF razinR was not the major factor contributing to the bacterial loss in the YSCWM areas. 展开更多
关键词 Yellow Sea Cold Water mass heterotrophic nanoflagellates bacteria trophic coupling temperature
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Variations in seed size and seed mass related to tree growth over 5 years for 23 provenances of Quercus acutissima from across China
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作者 Hui Zhang Xiuqing Yang +2 位作者 Mukui Yu Youzhi Han Tonggui Wu 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期917-924,共8页
The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adul... The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adulthood, and little is known about how seed traits and original environment affect seedling/tree growth over time. In this study, seed size, seed mass, seedling/tree growth and origins were collected and determined for 23 provenances of Quercus acutissima from across China. Origin variables correlated well with seed size and seed mass. In stepwise multiple regressions, a longitudinal aridity index explained 49.2-68.7% of the total variation in seed size and mass, while only seed width was correlated with seedling/tree height (H) and diameter at the ground (D) from seed traits and origins. The total variance in H and D explained by the models decreased over time, for example, the R <sup>2</sup> value of the models for H declined from 0.477 in the first year to 0.224 in the fourth year; no models was significant in the fifth year. These results indicate that seed size, regulated by the longitudinal aridity index strongly impacted seedling and tree growth, but the strength of the influence decreased over time, and disappeared after 4 years. 展开更多
关键词 Seed size Seed mass Provenance trial Seedling/tree growth Origins Quercus acutissima
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Nutrient-Induced Growth of Coliform and HPC Bacteria in Drinking-Water Pipes
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作者 Patrick Asamoah Sakyi Roland Asare +1 位作者 Chris Anani Samuel Boakye Dampare 《Journal of Environmental Protection》 2012年第6期508-517,共10页
We conducted a study on a model drinking water distribution system to evaluate the impact of nutrient in the form of sodium acetate on the growth and survival of coliform and heterotrophic plate count (HPC) bacteria f... We conducted a study on a model drinking water distribution system to evaluate the impact of nutrient in the form of sodium acetate on the growth and survival of coliform and heterotrophic plate count (HPC) bacteria for a maximum of 21 days residence time of water in pipes. Our results show that, besides the nutrient added and the absence of any additional source of contamination and additional supply of nutrient, there was significant growth of the above mentioned bacteria in the pipes and bottles for a couple of days, after which the bacterial population began to decrease. The results indicate that the bacteria used the nutrient to grow and multiply until the nutrient was totally consumed and became depleted in the bulk water phase, after which the bacterial population reached a near stationary level and subsequently declined. This suggests the death of some of the bacteria and their dead cells were used by other bacteria for growth and survival. Using a detection limit of 3.3 CFU/100 mL for the coliforms, the study shows that after sometime, no bacteria were found in the water phase of the pipe, however, the biofilm in the pipes still harbored some of the bacteria. The results have revealed that the bacteria also have the tendency to move from the water phase to the biofilm since the latter provides a more suitable environment for bacteria to thrive on and grow, thus prolonging their survival in the system. 展开更多
关键词 COLIFORM HPC bacteria NUTRIENT Drinking-Water Pipes Biofilm bacterial growth
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Antimicrobial and plant growth-promoting activities of bacterial endophytes isolated from Calotropis procera(Ait.)W.T.Aiton
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作者 MUHAMMAD HAMAYUN NASIR KHAN +6 位作者 MUHAMMAD NAUMAN KHAN MUHAMMAD QADIR ANWAR HUSSAIN AMJAD IQBAL SUMERA AFZAL KHAN KHUSHNOOD UR REHMAN IN-JUNG LEE 《BIOCELL》 SCIE 2021年第2期363-369,共7页
Bacterial endophytes are beneficial to their hosts as they can fix nitrogen in the soil and make it available to the host.Endophytic bacteria also secrete plant growth-promoting hormones to support their host plants u... Bacterial endophytes are beneficial to their hosts as they can fix nitrogen in the soil and make it available to the host.Endophytic bacteria also secrete plant growth-promoting hormones to support their host plants under normal as well as stress conditions.The current study aimed to isolate endophytic bacteria from different parts of Calotropis procera,i.e.,roots,stem and leaves of Calotropis procera(Ait.)W.T.Aiton.Plants were collected from the Lundkhwar,district Mardan.A total of 12 bacterial strains,i.e.,six from roots,three from the stem and three from the leaves were isolated.The strains were screened for their growth-promoting activity in rice plants because rice shows a quick and easy response to the bioactive compounds present in the culture filtrate(CF)of the potent endophytic strains.The rice plants were cultivated in pots containing 30 mL of 0.8%w/v water-agar medium.The pots were placed in a growth chamber,operated at 28±0.3℃ for 14 h(day);and 25±0.3℃ for 10 h(night),at 70%relative-humidity.Among the isolated strains,R1,S1,S3,L1,R5 and R6 showed visible growth promotion in rice plants.The biochemical analysis revealed that the strains were able to produce indole acetic acid(IAA)and flavonoids in higher quantities.Moreover,the strains also produced bioactive compounds that inhibited the growth of Escherichia coli and Aspergillus flavus using the well diffusion method.From the results,it was concluded that these strains can secrete potent compounds that can promote the host plant growth and inhibit the growth of pathogenic microorganisms and,therefore,can be used as bio-fertilizer and bio-control agents. 展开更多
关键词 Endophytic bacteria growth promotion Antimicrobial activity Plant-microbe interaction
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Growth Characteristics of <i>Fuirena umbellata</i>in a Surface Flow Constructed Wetland and Its Influence in Nutrients and Faecal Bacteria Removal from Domestic Wastewater in Cameroon
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作者 Martin Lekeufack Théophile Fonkou Etienne Pamo Tedonkeng 《Journal of Environmental Protection》 2017年第2期171-193,共23页
Various configurations of vegetated bed systems with a variety of macrophytes have been tested experimentally in Cameroon, for the treatment of domestic wastewater. The aim of this work was to assess the growth and bi... Various configurations of vegetated bed systems with a variety of macrophytes have been tested experimentally in Cameroon, for the treatment of domestic wastewater. The aim of this work was to assess the growth and biomass production of Fuirena umbellata (Cyperaceae) and its potentials in the removal of faecal bacteria and nutrients from primarily treated domestic effluent. A wetland vegetated with this macrophyte and a non-vegetated wetland (control) were continuously fed with primarily treated domestic wastewater at an estimated loading rate of 205 Litres/day in dry and rainy seasons for two consecutive years. Physicochemical and microbiological parameters of the effluent were monitored at the inflow and outflows of the wetlands alongside with the growth and productivity attributes of the young plants during each season. The density of plants ranged in the wetland from 17 - 185 plants/m2 and from 11 - 146 plants/m2 respectively during the first and the second years. More biomasses were instead produced in the dry seasons than in the rainy seasons but with no significant differences observed. As for nutrients removal, higher efficiencies were observed in the vegetated wetland (45% - 73%) compared to the non-vegetated control (17% - 66%). Similar trends were observed for the faecal bacteria but with no significant differences between the seasons. However, the vegetated beds were significantly more efficient than the non-vegetated control in the reduction of many physicochemical parameters and faecal bacteria. This varied with the seasons. 展开更多
关键词 growth Characteristics Fuirena umbellata NUTRIENTS FAECAL bacteria REMOVAL Surface Flow Wetland Local MACROPHYTE
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Plant Growth-Prompting Bacteria Influenced Metabolites of <i>Zea mays var. amylacea </i>and <i>Pennisetum americanum p. </i>in a Species-Specific Manner
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作者 Faten Dhawi Anna Hess 《Advances in Biological Chemistry》 2017年第5期161-169,共9页
Poor soil is one of the agricultural world’s principal challenges, inciting the use of chemical fertilizer’s to improve overall soil quality. However, the use of chemical fertilizer has significant and cascading env... Poor soil is one of the agricultural world’s principal challenges, inciting the use of chemical fertilizer’s to improve overall soil quality. However, the use of chemical fertilizer has significant and cascading environmental consequences. Therefore, the use of beneficial microbes’ inoculation in treating poor soil is a considerably ecofriendly sustainable solution. In the current study, we supplemented nutrient-deprived soil with plant growth promoting bacteria (PGPB), Pseudomonas fluorescens. The bacterial inoculations of Pseudomonas fluorescenswere added to the poor soil following two days post-sowing of Zea mays var. amylacea and Pennisetumamericanum p. seedlings. Metabolite analyses were conducted two months after treatment for both shoots and roots using nuclear magnetic resonance method (NMR). The data indicated significant changes in 19 metabolites relative to control in both plants shoot and roots. Among these metabolites, 7 were upregulated in roots of Zea mays var. amylacea, and 9 metabolites were upregulated in roots of Pennisetum americanum p. The PGPB enhanced sugars (fructose, glucose, sucrose) and amino acids (glutamate, alanine and succinate) in roots, while down regulating in shoots of Pennisetum americanum p. The Pseudomonas fluorescens induced, predominantly,Aminoacyl-tRNA related metabolite, and Alanine, aspartate and glutamate metabolite biosynthesis in Zea mays var. amylacea), whereas PGPB induced metabolites in Pennisetum americanum p., dominated by up regulated carbohydrate related (starch and sucrose) metabolites. The difference in some metabolic response between the two plants indicated that PGPB influence has a species-specific manner. 展开更多
关键词 Zea mays VAR. amylacea Soil Plant growth Promoting bacteria Pseudomonas FLUORESCENS Pennisetum americanum p. METABOLITES
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Isolation of Six Phosphate Dissolving Rhizosphere Bacteria (Bacillus subtilis) and Their Effects on the Growth, Phosphorus Nutrition and Yield of Maize (Zea mays L.) in Mali
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作者 Lamine Traore Hamadoun Babana +4 位作者 Hani Antoun Messaoud Lahbib Ousmane Sacko Cindy Nakatsu Diane Stott 《Journal of Agricultural Science and Technology(B)》 2016年第2期93-107,共15页
The disadvantages of the long term application of Tilemsi natural phosphate (TNP) on maize (Zea mays L.) production has come out because of its low P availability. Some functional soil microbes, such as phosphate ... The disadvantages of the long term application of Tilemsi natural phosphate (TNP) on maize (Zea mays L.) production has come out because of its low P availability. Some functional soil microbes, such as phosphate dissolving bacteria, have great potential in improvement of P solubility from TNP and P uptake by plants. The present study aimed to isolate and characterize typical phosphate dissolving bacterial strains (Bacillus subtilis) from Malian soils, and investigate their role in P uptake by maize grown in soils amended with TNP. The experimental design was a split plot with three main plots of fertilizers sources, i.e., natural phosphate, commercial fertilizer and without fertilizer, and with seven sub-plots of six microorganisms plus the control. The field experiment results have shown that the maize inoculated with the phosphate dissolving bacteria was improved in seed germination, plant growth, plant production (increase yield by 42%), grain and aerial dry biomass (P) content of 34% and 64%, respectively. They have also shown that the locally available TNP can be used by the Malians farmers in maize culture and have comparable production to the one obtained with the costly imported commercial phosphate fertilizer, like the complex cereal. The project has provided information for the combined use of the Mali TNP and phosphate dissolving bacteria Bacillus subtilis subsp, subtilis (T): DSM 10 in improvement of maize production in the country. 展开更多
关键词 MAIZE PHOSPHATE microorganisms characterization growth production bacteria.
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Effect of Supplementation of Conjugated Linoleic Acid in Diets on Growth Performance and Total Lactic Bacteria iin Small Intestine of Broiler
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作者 T. Chanuwat S. Wongsuthavas B. Smerjai C. Yuangklang K. Vasupen 《Journal of Agricultural Science and Technology(A)》 2011年第8期1141-1143,共3页
The effect of supplementation of conjugated linoleic acid (CLA) in diets on growth performance and total lactic bacteria (LAB) in small intestine of broiler. One hundred sixty eight broilers (Arbor Acres; 1 wk ol... The effect of supplementation of conjugated linoleic acid (CLA) in diets on growth performance and total lactic bacteria (LAB) in small intestine of broiler. One hundred sixty eight broilers (Arbor Acres; 1 wk old) were randomly assigned to 8 groups. Each group (male 21 and female 21 broiler chickens) was further randomly divided into 3 replicates of 7 chickens were assigned to 4 dietary treatments (0%, 0.5%, 1.0%, and 1.5% CLA). Feed consumption and BW were recorded at every 7-day period. On day 56, and each week were collected at ileal content in small intestine for the total count of lactic acid bacteria (LAB). There were highly significant differences in body weight gain, average dairy feed intake, average dairy gain and feed conversion ratio among the treatments (P 〈 0.01). Moreover, our results revealed that the highest detection trend from the ileal occurred during the period in the supplementation of CLA. 展开更多
关键词 BROILER conjugated linoleic acid growth performance lactic acid bacteria.
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Numerical Simulation of the Multicomponent Mass Transfer during Bridgman Growth of CdZnTe Crystal Using Maxwell-Stefan Diffusion Model
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作者 殷利迎 介万奇 +2 位作者 WANG Tao ZHOU Boru YANG Fan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期349-357,共9页
To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman ... To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman growth of CdZnTe crystal. The Maxwell-Stefan diffusion coefficients in the melt were estimated. Distributions of Zn, Cd, and Te were calculated with variable ampoule traveling rate and diffusion coefficients. The experimental results show that Zn in melt near the growth interface decreases and diffuses from the bulk melt to the growth interface. For Cd, the situation is just the opposite. The coupling effects of Zn and Cd diffusions result in an uphill diffusion of Te at the beginning of the growth. Throughout the growth, the concentration of Te in the melt keeps low near the growth interface but high far from the growth interface. Increasing the ampoule traveling rate will aggravate the segregation of Zn and Cd, and hence deteriorate the uniformity of Te. We also find that not only the diffusion coefficients but also the ratios between them have significant influence on the species diffusions. 展开更多
关键词 semiconducting ternary compounds CdZnTe crystal growth computer simulation multicomponent mass transfer
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Responses of phytoplankton and its satellite bacteria to exogenous ethanol
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作者 Rediat ABATE Buce Hanoch HETHARUA +9 位作者 Vishal PATIL Daner LIN Demeke KIFLE Junrong LIANG Changping CHEN Lin SUN Shuh-Ji KAO Yonghong BI Bangqin HUANG Yahui GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期203-214,共12页
The response of phytoplankton and its satellite bacteria to various concentrations(0.01%-10%v/v)of ethanol is studied.To elucidate the effect of ethanol,single-strains of phytoplankton(SSP)culture,pure strains of sate... The response of phytoplankton and its satellite bacteria to various concentrations(0.01%-10%v/v)of ethanol is studied.To elucidate the effect of ethanol,single-strains of phytoplankton(SSP)culture,pure strains of satellite bacteria isolated from nonaxenic SSP cultures,and Escherichia coli were screened.Results indicate that ethanol could promote the growth and photo synthetic efficiency(F_(v)/F_(m))of S SP at 0.01%and the growth of satellite bacteria at 0.01%-1%.Nevertheless,ethanol inhibited the growth and F_(v)/F_(m)of SSP at 0.1%-1%,and killed bacteria and SSP at 10% concentration.Further investigation on a satellite bacterium(Mameliella alba)revealed that ethanol promotes growth by serving as a growth stimulant rather than a metabolic carbon source.The 16 S rRNA gene amplicon indicated that all nonaxenic S SP cultures harbor distinct satellite bacteria communities where the SSP culture of Skeletonema costatum,Phaeodactylum tricornutum,and Dunaliella bardawil were dominated by bacteria genera of Marivita(~80%),Dinoroseobacter(~47%),and Halomonas(~87%),respectively,indicating that every SSP cultures have their own distinct satellite bacterial community.The bacteria family Rhodobacteraceae was dominant in the two marine diatoms,whereas Halomonadaceae was dominant in the saline green microalga.Compared to their respective controls,the supply of 0.5% ethanol to SSP cultures promoted the growth of the satellite bacteria but did not cause a significant difference in species composition of satellite bacteria.Therefore,a low concentration of ethanol can promote the growth of bacteria in a non-selective way.This study enriched our knowledge about the effect of ethanol on aquatic microbes and provided a baseline for basic and applied biotechnological re search in the aquatic environment in the future. 展开更多
关键词 aquatic microbes bacteria diversity ethanol effect growth inhibition growth stimulation
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