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1.
该试验旨在研究蒸汽爆破对小麦麸皮水溶性戊聚糖含量的影响。选用市售普通小麦麸皮为原料,进行不同水料比和维压时间的蒸汽爆破处理,分别为未汽爆处理的(对照组)、处理组蒸汽压强固定为2.0 MPa,对水料比为20%、30%、50%的麸皮分别进行维压时间为30、60、120 s蒸汽爆破处理。试验结果表明,蒸汽爆破可显著提高小麦麸皮水溶性戊聚糖的含量(P0.05)。与对照组相比,在相同蒸汽压强下,蒸汽爆破处理组的水溶性戊聚糖质量分数随维压时间的延长而显著提高(P0.05),蒸汽维压处理60 s,小麦麸皮中水溶性戊聚糖的含量可提高9.0倍(P0.05)。与对照组相比,蒸汽爆破处理组的水溶性戊聚糖含量随水料比的提高而呈不同程度地提高(P0.05),水料比为30%时,小麦麸皮中水溶性戊聚糖的含量可提高9.4倍(P0.05)。综合考虑蒸汽爆破处理的提取效率与能量消耗,蒸汽爆破小麦麸皮的蒸汽压强为2.0 MPa时,适宜的水料比为30%,适宜的蒸汽爆破时间为60 s。此时,与未处理麸皮相比,小麦麸皮中水溶性戊聚糖质量分数可从1.3%提高到13.9%,提高10.8倍,中性洗涤纤维可降低17.2%(P0.05),半纤维素可降低26.7%(P0.05),半纤维素热解阶段的活化能值可提高21.5%。该研究证实蒸汽爆破技术有助于提高小麦麸皮功能性活性多糖(水溶性戊聚糖)的含量,有助于提高小麦麸皮的深加工利用。 相似文献
2.
为探索减少或控制反刍动物向大气中排放污染物的方法,该文就日粮类型对绵羊甲烷排放及代谢物中碳残留的影响进行探讨。试验选择60只4月龄、体重为25 kg左右的新疆细毛羊进行完全随机试验设计分成4组。Ⅰ组和Ⅱ组日粮精粗比为2：8,Ⅲ组和Ⅳ组日粮精粗比为4：6,Ⅰ组和Ⅲ组粗饲料为玉米秸秆,Ⅱ组和Ⅳ组粗饲料为玉米青贮。结果表明,用玉米青贮完全替代玉米秸秆饲喂绵羊时,甲烷产量Ⅱ组比Ⅰ组显著降低（P＜0.01）,Ⅳ组比Ⅲ组降低了12%（P＞0.05）。当粗饲料为玉米秸秆时,产甲烷效率随日粮精粗比的提高显著降低（P＜0.05）。当粗饲料为玉米青贮时,产甲烷效率组间差异不显著（P＞0.05）。代谢物中的碳残留量Ⅳ组比Ⅰ组显著降低（P＜0.05）,Ⅱ组和Ⅳ组分别比Ⅰ组和Ⅲ组降低16.67%和9.09%（P＞0.05）。研究结果表明,日粮类型对新疆细毛羊排放甲烷有显著影响,同时也影响其代谢物中碳的残留量。 相似文献
3.
为青贮玉米生产实践选择适宜压实度。该研究通过探究不同压实度对玉米(Zea mays L.)青贮营养、发酵品质及有氧稳定性的影响。建立多元线性回归模型为生产实践提供参考。以新饲玉10号青贮玉米为材料,发酵装料密度设计为5个水平(350、400、500、600、700 kg/m~3),发酵期为50 d,检测开窖后各青贮压实度在第0、12、24、36、60、108 h时的营养成分和发酵品质的变化,并用多通道温度记录仪监测温度变化,建立多元线性回归模型。结果表明,350 kg/m~3青贮压实度处理组中干物质(dry matter)和粗蛋白(crude protein)密度相比500、600和700 kg/m~3青贮压实度处理,始终显著降低了2.6%~11.9%和22.8%~37.0%(P0.05);与500、600和700 kg/m~3压实度处理组中的中性洗涤纤维(Neutral detergent fiber)、酸性洗涤纤维(acid detergent fiber)、氨态氮(NH3-N)浓度以及p H值相比,350 kg/m~3青贮压实度处理显著提高了1.2%~4.6%,6.2%~14.1%,14.1%~37.4%和3.1%~39.9%(P0.05)。各指标与开窖时间、压实度和发酵温度间的多元线性回归模型拟合度达到76.8%~92.3%,R2达到0.590~0.853。其中,CP浓度的拟合度和R2最高。因此,增加青贮压实度,可改善开窖后青贮营养、发酵品质,提高有氧稳定性,压实度为600 kg/m~3的玉米青贮发酵品质及有氧稳定性最好,建议600 kg/m~3为全株玉米最佳青贮压实度,对于指导生产实践具有重要意义。 相似文献
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筛选复配适合宁夏地区的青贮微生物菌剂,可解决在青贮自然发酵过程中,青贮玉米营养损失多且易发霉等问题。本研究对从宁夏中部干旱区自然发酵的青贮玉米饲料中分离鉴定的1株乳酸菌(Lactobacillus acidophilus)和1株酵母菌(Saccharomyces cerevisiae)进行性能测定,复配后形成复合菌剂并进行45 d的大型窖贮青贮发酵试验,设置不添加菌剂和添加商业菌剂的青贮饲料为对照组。营养成分测定结果显示,与不加菌剂和添加商业菌剂的对照组相比,经复合菌剂处理后饲料中性洗涤纤维和酸性洗涤纤维显著下降(P0.05),干物质和粗脂肪含量显著增加(P0.05),粗蛋白含量变化不显著。为期75 d的滩羊肥育饲喂和5 d的消化代谢试验表明,对照组与试验组滩羊的日均采食量差异显著(P0.05),平均日增重、末重、料重比差异不显著。试验组滩羊对青贮玉米饲料中粗蛋白、粗脂肪表观消化率显著提高(P0.05),中性洗涤纤维表观消化率提高,对酸性洗涤纤维的表观消化率影响不显著。结果表明,复合菌剂显著改善了青贮玉米饲料的品质,复合菌剂发酵的饲料玉米对滩羊生长有良好的促进作用。 相似文献
5.
前处理对玉米秸秆蒸汽爆破效果的影响 总被引：3，自引：1，他引：2
为提高纤维乙醇生产过程中秸秆的预处理效果,该文研究了水预浸和CaO前处理对蒸汽爆破和酶解糖化的影响,并利用场发射扫描电镜(FE-SEM)、X-射线衍射仪(XRD)及傅里叶红外光谱仪(FTIR)对其影响机制进行了分析。结果表明:玉米秸秆经30%水(水料质量比30:100)预浸5d、经2%CaO(CaO与秸秆质量比2:100)处理3d或经30%水和2%CaO协同处理1d后再进行蒸汽爆破均可显著提高蒸汽爆破对木质素的降解,降解率由单独蒸汽爆破的20.6%分别提高到27.8%、35.1%和30.9%。玉米秸秆经3种复合预处理和酶解糖化后总糖浓度分别为3.81、3.59和3.46g/100mL,糖得率分别为42.2%、39.8%和38.3%,比单独蒸汽爆破预处理分别提高了23.7%、16.6%和12.3%。水预浸或CaO复合蒸汽爆破预处理后秸秆结构破坏严重,秸秆相对结晶度由单独蒸汽爆破的42.6%分别提高到47.0%和54.5%。水浸泡或CaO前处理可提高蒸汽爆破预处理效果和后期糖化效果,且所用试剂价格低廉,可以应用推广。 相似文献
6.
不同切碎方式对全株玉米青贮饲料品质影响的试验研究 总被引：5，自引：0，他引：5
该试验以乳熟期全株玉米为青贮原料，分别进行揉切、粉碎和切断处理，使用60 L青贮桶作为青贮装置，在室温下密封贮藏60 d后开封。试验结果表明：试验所用全株玉米的干物质含量为23.53％、可溶性碳水化合物含量为9.12％、粗蛋白含量为9.35％，为优质的青贮原料。经不同切碎方式的各组青贮饲料的有机酸含量均无显著差异(P＞0.05)，pH值均在4.0以下，而且氨态氮与总氮的质量比也均在5.0以下，达到了优质青贮饲料的标准，虽然各青贮饲料的粗蛋白、粗灰分和可溶性碳水化合物含量有显著差异(P＜0.05)，但均为优质的青贮饲料。综合比较，揉切青贮饲料的发酵品质和消化效果最好。 相似文献
7.
棉花秸秆双支撑切割性能试验 总被引：1，自引：7，他引：1
针对现有往复式切割器切割收获棉花秸秆过程中存在切割质量差与切割刀片易损坏等问题,该文利用自制的棉花秸秆切割试验台和高速摄影系统,以棉秆单位直径最大切割力和单位面积切割功为目标值,对平均切割速度、切割倾角和切割速比等影响因素进行了棉秆往复式双支撑切割条件下的单因素试验、中心组合试验和验证试验。利用响应面法对中心组合试验数据进行了处理,建立了目标值与各影响因素之间的回归模型,优化了往复式双支撑切割器切割棉花秸秆时的工作参数。试验结果表明,平均切割速度和切割倾角对棉花秸秆单位直径最大切割力和单位面积切割功的影响显著(P0.01),切割速比影响不显著(P0.05),但切割速比对棉秆切割截面的质量具有重要影响;当切割速比为1.25和1.5时棉秆一次切断率为85%,比切割速比为1、1.75和2时高出10%~15%,割茬高度比切割速比为1、1.75和2时低10~30 mm;利用往复式双支撑切割器切割棉花秸秆时的工作参数的最佳组合是:平均切割速度为0.9 m/s、切割倾角为12.7°、切割速比在1.25~1.5之间,该条件下的棉秆切割性能目标值的平均实测值与预测值的误差均小于7%,表明棉花秸秆往复式双支撑切割器工作参数的优化结果可靠。该研究为高效、低耗的棉花秸秆切割收获机械装备及其切割器的研制和使用提供参考。 相似文献
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为了解肉牛舍安装接力送风和饲粮中添加烟酸铬对肉牛生长性能、肉牛生理和牛舍环境的影响,研究了南方夏季安装接力送风机和饲粮添加铬对拴系敞篷饲养肉牛舍热环境及对肉牛日增质量的影响。试验采用双因素设计,选取36头平均体质量为392.8 kg的西杂肉牛,随机分成4个处理,处理1组牛舍安装风机,并在饲粮中添加烟酸铬;处理2安装风机,饲粮中不添加烟酸铬;处理3组不安装风机,但饲粮中添加烟酸铬;处理4(对照组)不安装风机,不添加烟酸铬。铬的添加量为800μg/kg,进行为期30 d生长试验。试验分别测定了牛舍的环境指标、肉牛生理指标和肉牛日增质量,并对经济效益进行了分析。结果如下:1安装接力送风机牛舍14:00平均室温可降低1.9℃(P0.01),风速增加5.6倍(P0.01),降低温湿指数(temperature and humidity index,THI)5.65%(P0.01);2饲粮添加铬降低热应激肉牛呼吸频率2.37次/min(P0.01),降低直肠温度0.18℃(P0.01),安装风机降低呼吸频率6.97次/min(P0.01),安装风机和饲粮添加铬对肉牛呼吸频率和直肠温度无交互作用。3处理1组肉牛平均日增质量比处理2、处理3和对照组分别提高了44.16%(P0.05)、35.37%(P0.05)和79.03%(P0.05)。处理2组和处理3组比对照组平均日增质量提高了24.19%(P0.05)和32.26%(P0.05)。处理1组比对照组增加毛利8.72元/(头·d)。表明南方夏季肉牛舍安装风机和饲粮中添加铬800μg/kg均缓解了肉牛湿热应激,提高了平均日增质量和经济效益,二者结合使用效果较好。 相似文献
9.
蒸汽爆破预处理和微生物发酵对玉米秸秆降解率的影响 总被引：7，自引：2，他引：5
为了提高玉米秸秆的利用效率,首先对玉米秸秆进行蒸汽爆破预处理（压力2.5 Mpa,维压200 s）,然后再进行米曲霉发酵,研究物理和生物学处理对秸秆成分及相关酶活变化的影响。结果表明,蒸汽爆破使秸秆中纤维素、半纤维素和木质素的降解率分别达到8.47%、50.45% 和36.65% （p＜0.05）。爆破预处理的秸秆再经米曲霉发酵6 d后,秸秆中纤维素和半纤维素的降解率分别为27.89%和64.80% （p＜0.05）,发酵秸秆中的滤纸酶、羧甲基纤维素酶、淀粉酶和蛋白酶活力分别达到335.10、1138.92、1954.20和201.99 U/g。爆破预处理后进行米曲霉发酵,对于提高玉米秸秆的降解率具有非常重要的意义。 相似文献
10.
封闭型牛舍风机喷淋降温和饲粮添加铬改善肉牛生长性能 总被引：1，自引：3，他引：1
为了探索南方夏季缓解肉牛热应激的方法和措施,研究了安装接力送风机加喷淋降温和饲粮添加铬对封闭型房舍式小群饲养肉牛生产性能和牛舍热环境的影响。试验采用双因素设计,选取28头平均体质量379.3kg的西杂肉牛,随机分成4组,试验1组牛舍安装风机加喷淋,并在饲粮中添加烟酸铬;试验2组安装风机加喷淋,饲粮中不添加烟酸铬;试验3组不安装风机加喷淋,但饲粮中添加烟酸铬;试验4组(对照组)不安装风机加喷淋,不添加烟酸铬。铬的添加量为800μg/kg,进行为期30 d生长试验。分别测定了牛舍的环境指标、肉牛生理指标和肉牛增质量,并对经济效益进行了分析。结果如下:1安装接力送风机加喷淋系统牛舍14:00平均室温可降低1.84℃(P0.01),风速增加8.27倍(P0.01);2安装风机加喷淋降温降低肉牛呼吸频率4.93次/min(P0.01),饲粮添加铬降低直肠温度0.23℃(P0.01),安装风机加喷淋降温和饲粮添加铬对肉牛呼吸频率和直肠温度无交互作用。31组肉牛平均日增质量比2组、3组和对照组分别提高了12.37%(P0.05)、19.59%(P0.05)和34.02%(P0.05)。2组比对照组平均日增质量提高了24.71%(P0.05)。1组比对照组增加毛利4.44元/(头·d)。表明南方夏季肉牛舍安装风机加喷淋和饲粮中添加铬均缓解了肉牛热应激,提高了平均日增质量和经济效益,二者结合使用效果较好。 相似文献
11.
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
13.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
14.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献
15.
Grete Skrede Berit Karoline Martinsen Anne-Berit Wold Stein-Erik Birkeland Kjersti Aaby 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):193-208
Abstract A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species. 相似文献
16.
《Communications in Soil Science and Plant Analysis》2012,43(7):865-877
Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L?1 nitric acid (HNO3) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L?1 ammonium acetate (NH4OAc) and 1.0 mol L?1 HNO3 extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils. 相似文献
17.
Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater 总被引：3，自引：0，他引：3
Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells. 相似文献
18.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
19.
Y. Bashan J. J. Bustillos L. A. Leyva J.-P. Hernandez M. Bacilio 《Biology and Fertility of Soils》2006,42(4):279-285
Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several
photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene.
This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments
for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference
in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless
of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots.
Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production
or the positive response of the plants towards A. brasilense Cd inoculation. 相似文献
20.
Three slow-growing legume trees used for desert reforestation and urban gardening in the Sonoran Desert of Northwestern Mexico
and the Southwestern USA were evaluated whether their growth can be promoted by inoculation with plant growth-promoting bacteria
(Azospirillum brasilense and Bacillus pumilus), unidentified arbuscular mycorrhizal (AM) fungi (mainly Glomus sp.), and supplementation with common compost under regular screenhouse cultivation common to these trees in nurseries. Mesquite
amargo (Prosopis articulata) and yellow palo verde (Parkinsonia microphylla) had different positive responses to several of the parameters tested while blue palo verde (Parkinsonia florida) did not respond. Survival of all tree species was over 80% and survival of mesquite was almost 100% after 10 months of cultivation.
Inoculation with growth-promoting microorganisms induced significant effects on the leaf gas exchange of these trees, measured
as transpiration and diffusive resistance, when these trees were cultivated without water restrictions. 相似文献