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1.
A field experiment was conducted using a 3 × 3 orthogonal regression design to explore the growth promotion of one-year-old Yunnan pine seedlings (Pinus yunnanensis Franch.) in response to foliar application of IAA (indole-3-acetic acid) at rates of 0, 200 and 400 mg·L(-1) and IBA (indole-3-butyric acid) at rates of 0, 200 and 400 mg·L(-1) in order to promote the growth during the seedlings' early stage. The experiment was conducted at the Lufeng Village Forest Farm of Yiliang County in Kunming, Yunnan, China. The results showed that IAA and IBA were effective in growth promotion of Yunnan pine seedlings. The response of both growth increment and biomass accumulation to the concentration of IAA and IBA can be modeled using a bivariate surface response, and each growth index had a peak value. Growth indexes increased with the increase of the dosage of photohormones before reaching a peak value, and then decreased. The different growth indexes had various responses to the concentrations and ratio of IAA and IBA. The foliar application of IAA in combination with IBA showed the largest improvement on the biomass of the needles, followed by stems and roots. The higher ratio of IAA promoted stem diameter growth, root system development and biomass accumulation in the needles, while a higher ratio of IBA contributed to height growth and biomass accumulation in the stem. Based on the auxin effect equations on the different growth indexes and surface response, the optimum concentrations and the (IAA:IBA) ratios can be obtained. The optimum concentrations of IAA and IBA were 167 and 186, 310 and 217, 193 and 159, 191 and 221, and 206 and 186 mg·L(-1), with corresponding ratios of 1:1.11, 1:0.70, 1:0.82, 1:1.15 and 1:0.90, respectively, at the maximum seedling height and collar diameter growth as well as biomass accumulation at the root, stem and needle. The above growth indexes were 22.00%, 79.80%, 48.65%, 82.20% and 107.00% higher than the control treatment.  相似文献   

2.
DA-6缓解胺苯磺隆对后茬水稻伤害的作用   总被引:7,自引:0,他引:7  
刘祥英  柏连阳 《现代农药》2005,4(3):31-32,35
室内采用土培法分别测定了不同浓度胺苯磺隆和不同浓度己酸二乙氨基乙醇酯(简称DA-6)对水稻生长的影响以及不同浓度胺苯磺隆处理下DA-6对水稻根生长的影响。结果表明,胺苯磺隆处理浓度自0.1μg/kg起,明显抑制水稻幼苗的生长,且对主根长和根鲜重的抑制作用较株高和株鲜重更为严重;当DA-6浓度在0.5~20mg/L范围内,水稻根长和根鲜重高于对照,其中以5mg/L最好;用5mg/L的DA-6浸种可不同程度地缓解0.1~20μg/kg的胺苯磺隆对水稻的伤害。  相似文献   

3.
肉苁蓉细胞继代培养过程中的褐变控制   总被引:4,自引:0,他引:4  
肉苁蓉细胞在培养过程中易发生褐变. 通过对褐变前后细胞的多酚含量、褐变强度与多酚氧化酶活性的比较,确定了肉苁蓉多酚氧化酶酶促褐变是肉苁蓉褐变的主要原因. 通过测定不同pH下的酶活性,确定肉苁蓉多酚氧化酶的最适pH为5.8~6.0. 在最适pH条件下,比较了维生素C(Vc)、柠檬酸、Na2SO3等对肉苁蓉多酚氧化酶活性的影响,发现这几种物质对多酚氧化酶活性均有抑制效果,其中Vc随浓度的增大对多酚氧化酶的抑制作用显著,当其浓度达到0.6 mg/L时,多酚氧化酶的酶活降低为最适酶活的5.1%. 进一步在肉苁蓉细胞继代培养中添加Vc配合使用活性炭,优化出Vc-活性炭培养基. 添加1.0 g/L活性炭和3.0 mg/L Vc(附加1.0 mg/L IAA和4.0 mg/L KT)的B5培养基能有效抑制细胞褐变,使细胞褐变程度仅为原来的21%,细胞生长旺盛,最大细胞相对增长量(干重)提高了25.4%.  相似文献   

4.
Bacillus thuringiensis in entrapped in k-carrageenan was capable of producing indole-3-acetic acid (IAA) in the presence of rock phosphate ore (RPO). After five repeated batch fermentation experiments, an average of 6.9 mg/L IAA was recorded in the presence of 1.5 g/L RPO and 4.7 mg/L IAA in the RPO-free control. The bacterium simultaneously solubilized phosphates with a maximum soluble P of 115 mg/L and 150 mg/L after the fourth batch cycle in 1.5 and 3.0 g/L RPO amendment, respectively. Addition of tryptophan to the media increased IAA production to 13.9 and 20.7 mg/L per batch on RPO-free and 1.5 g/L RPO-supplemented media with poor bacterial growth and RPO solubilization.  相似文献   

5.
Bacillus thuringiensis in entrapped in k-carrageenan was capable of producing indole-3-acetic acid (IAA) in the presence of rock phosphate ore (RPO). After five repeated batch fermentation experiments, an average of 6.9 mg/L IAA was recorded in the presence of 1.5 g/L RPO and 4.7 mg/L IAA in the RPO-free control. The bacterium simultaneously solubilized phosphates with a maximum soluble P of 115 mg/L and 150 mg/L after the fourth batch cycle in 1.5 and 3.0 g/L RPO amendment, respectively. Addition of tryptophan to the media increased IAA production to 13.9 and 20.7 mg/L per batch on RPO-free and 1.5 g/L RPO-supplemented media with poor bacterial growth and RPO solubilization.  相似文献   

6.
Allelopathic effects of entire shoot extract, plant part extracts, and shoot residue of parthenium (Parthenium hysterophorus L.) on corn (Zea mays L.), ryegrass (Lolium multiflorum Lam.), wheat (Triticum aestivum L.), velvetleaf (Abutilon theophrasti Medik.), and soybean [Glycine max (L) Merr.] growth were examined. Parthenium shoot contained water-soluble materials that were toxic to root growth of velvetleaf and wheat. At 4% (w/ v) concentration, root growth of velvetleaf and wheat were reduced by 60 and 75%, respectively. The order of increasing sensitivity to parthenium was ryegrass, corn, wheat, and velvetleaf. There was a strong correlation between extract concentration and increased toxicity to test species. The toxicity of plant part extracts was also concentration dependent. At 1 and 2% (w/v), the inflorescence and leaves caused more root inhibition than stem extract. Parthenium shoot incorporated in soil at 1% (w/w) caused significantly more root inhibition of wheat than soybean, corn, and ryegrass. At 4% (w/w), root growth of all the test species was inhibited compared to the control. Toxicity of parthenium residue to wheat diminished with increasing periods of decomposition. Residue decomposed for four weeks was less toxic than the undecomposed residue.Florida Agricultural Experiment Stations Journal Series No. 7506.  相似文献   

7.
A series of laboratory bioassays were utilized to test for the presence of potential plant growth factors in saliva from a large native ungulate, the North American bison (Bison bison L.). Whole saliva enhancedAvena coleoptile growth at high pH, whether alone or in combination with indoleacetic acid (IAA). However, this enhancement was a result of salts in the saliva (primarily NaHCO3) rather than of other compounds acting hormonally, enhancing IAA activity, or inhibiting IAA oxidase activity as possibly occurs with some insect salivas. Additionally, the absence of detectable cytokinins in the saliva was indicated by its failure to enhance cucumber cotyledon expansion. This suggests that biochemical control of plant growth by salivary compounds following grazing is probably not an important component of this ruminant's interactions with its food plants, as has been suggested for some herbivores.  相似文献   

8.
目的探讨L-精氨酸(L-Arg)对高糖高胰岛素(High glucose and insulin,HGI)诱导心肌细胞肥大的抑制作用。方法体外培养乳鼠心肌细胞,将细胞分为正常对照组(5.5mmol/L葡萄糖)、模型组(HGI组,给予25.5mmol/L葡萄糖与0.1μmol/L胰岛素)、L-Arg低、中、高剂量组(给予HGI组药物,并分别加入0.01、0.1和1.0mmol/L的L-Arg)和L-Arg+L-NAME组[给予HGI组药物,并加入0.1mmol/LL-Arg和一氧化氮合酶(Nitric oxide synthase,NOS)特异性抑制剂L-NAME],以细胞表面积、蛋白质含量和心房利钠因子(Atrial natriuretic factor,ANF)mRNA表达为反映心肌肥大的指标,观察L-Arg对HGI致心肌细胞肥大作用的影响;采用Real-timePCR法检测内皮型一氧化氮合酶(Endothelial NOS,eNOS)和诱生型一氧化氮合酶(Inducible NOS,iNOS)mRNA的表达;比色法和硝酸还原法分别检测细胞培养液中NOS的活性和NO的含量。结果 L-Arg呈浓度依赖性地抑制HGI诱导的心肌细胞肥大;并上调eNOS mRNA的表达及NOS的活性,增加NO的浓度。NOS抑制剂L-NAME可完全阻断L-Arg的上述作用。结论 L-Arg可通过激活eNOS表达,促进NO释放,产生抗HGI诱导心肌肥大的作用。  相似文献   

9.
郑春明  徐礼根 《农药》1999,38(12):22-23
用0.001、0.01、0.1、1.0mg/L的三十烷磷酸酯钾(TPK)溶液培养小麦、水稻幼苗。其促进幼苗根、茎叶器官生长的能力以0.01mg/L为最佳,使小麦幼苗的苗高、苗鲜重、苗干重、根长、根鲜重、根干重、全株鲜重和全株干重分别比甭水对照提高17.1%、17.0%、18.4%、16.4% ̄11.0%、12.0%、15.0%和17.0%,使水稻幼的上述指标分别提高10.3%、11.0%、40.3  相似文献   

10.
The present study was performed to investigate the effects of chronic administration of nonylphenol (NP) on the expression of inflammation-related genes in the brains of mice. NP was given orally by gavages at 0, 50, 100, and 200 mg/kg/d. The expression of inflammatory enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), was evaluated by immunohistochemistry and immunoblotting assays. The nitric oxide (NO) level and nitric oxide synthase (NOS) activity were also measured by biochemical analyses. The results showed that NP at a high dose (200 mg/kg/d) significantly increased the expression of iNOS and COX-2 in both the hippocampus and cortex. In parallel with the increase in iNOS expression, the NO level was significantly greater at the dose of 200 mg/kg/d, compared to the control. The activity of NOS was also increased in the brain of mice at the dose of 100 and 200 mg/kg/d. These findings demonstrate that NP may have the potential to induce the chronic inflammation or cause neurotoxicity in the mouse brain.  相似文献   

11.
12.
《云南化工》2016,(5):13-17
以浮萍作为受试生物,分别以质量浓度为1、5、10 mg/L的氧化石墨烯碎片悬浮液,对浮萍进行96 h暴露处理,以分析氧化石墨烯对浮萍生长的影响。结果显示,10 mg/L的氧化石墨烯对浮萍叶片数和湿重的抑制率分别约为35.3%和26.1%,显著(P0.05)抑制了浮萍的生长;低浓度的氧化石墨烯对浮萍抗氧化酶无明显影响,当其浓度达10 mg/L时,浮萍内超氧化物歧化酶(SOD)过氧化氢酶(CAT)水平明显(P0.05)升高;过氧化物酶(POD)的活性则随着氧化石墨烯浓度的增加出现"低促高抑"的趋势。研究结果说明,氧化石墨烯在具有环境意义的低浓度下对浮萍无明显抑制作用,但在较高浓度(10 mg/L)下对浮萍具有显著的胁迫效应。  相似文献   

13.
l-Tryptophan caused growth inhibition of roots and hypocotyls (or coleoptiles) of cockscomb (Amaranthus caudatus L.), lettuce (Lactuca sativa L.), cress (Lepidium sativum L.), timothy (Phleum pratense L.), rice (Oryza sativa L.), wheat (Triticum aestivum L.), and oat (Avena sativa L.), increasing the dose ofl-tryptophan increased the inhibition. The concentrations for 50% inhibition of the root growth were 0.14, 0.15, 0.21, 0.79, 0.95, 1.7, and 2.4 mM for cockscomb, cress, lettuce, timothy, rice, wheat, and oat, respectively; the concentrations for 40% inhibition of the hypocotyl (or coleoptile) growth were 0.28, 0.33, 0.43, 2.7, 4.5, 7.2, and 15 mM for cockscomb, cress, lettuce, timothy, rice, wheat and oat, respectively. The levels ofl-tryptophan in oat seedlings and in its root exudates were 29.3 mg/kg fresh wt and 0.25 mM under light conditions, and 21.1 mg/kg fresh wt and 0.18 mM under dark conditions, respectively. The presence ofl-tryptophan in the root exudates coupled with its effect on growth suggested thatl-tryptophan may play an important role in the growth inhibition of other plants in nature.  相似文献   

14.
王海  黄俊  王超 《应用化工》2011,40(2):187-190,194
以醋酸纤维素(CA)为原料,采用溶液浇铸法成膜。用物理包埋法将荧光指示剂固定CA膜中。以戊二醛为交联剂,将葡萄糖氧化酶固定于膜表面。研究了高碘酸钠、乙二胺、戊二醛、给酶量、pH值等固定化条件对酶活的影响,确定了优化的固定条件:在室温下与0.5 mol/L的高碘酸钠反应30 min;与0.04 mol/L的乙二胺反应150 min时;与溶度为1.5%(v/v)的戊二醛交联120 min;在4℃条件下,在pH6.5、给酶量35 mg/mL的酶液中交联21 h。利用SEM分析表明,荧光指示剂均匀分布膜中,成膜质量较好。通过优化固定条件,把荧光指示剂和葡萄糖氧化物酶(GOD)同时固定醋酸纤维素膜上,可以得到同时具有光敏感性和酶催化能力的复合敏感膜。  相似文献   

15.
目的探讨三七总皂苷对体外培养的人牙周膜细胞(Human periodontal ligament cell,hPDLC)增殖、碱性磷酸酶(Alkaline phosphatase,ALP)活性及表达的影响。方法采用组织块法原代培养hPDLC,并经免疫组化鉴定;分别用10、1.0、0.1和0.01 mg/L浓度的三七总皂苷处理体外培养的hPDLC,设只加含10%FBS的DMEM培养基为空白对照,分别于1、3、5、7 d后,MTT法检测其对hPDLC增殖活性的影响,酶标仪上检测细胞中ALP活性,Western blot法检测细胞中ALP蛋白的表达。结果免疫组化结果显示,细胞来源于外胚间充质;MTT结果显示,0.1 mg/L浓度组在第5天和1.0、10 mg/L浓度组在第3、5天hPDLC增殖活性明显高于空白对照组(P<0.01);0.1、1.0、10 mg/L浓度组在第3、5天ALP活性明显高于空白对照组(P<0.01),1.0 mg/L浓度组APL活性明显高于其他各组(P<0.01);0.01、0.1、1.0、10 mg/L浓度组ALP蛋白表达量均明显高于空白对照组(P<0.01),以1.0 mg/L浓度组ALP表达量最高。结论三七总皂苷有促进hPDLC增殖的作用,并能增加ALP活性及其表达水平。  相似文献   

16.
采用酶动力学方法研究了对羟基肉桂酸对酪氨酸酶单酚酶和二酚酶活力的抑制效应。结果表明,对羟基肉桂酸对酪氨酸酶单酚酶和二酚酶活性均有抑制作用,导致单酚酶活力和二酚酶活力下降50%的对羟基肉桂酸浓度约分别为0.12 mmol/L和0.50 mmol/L。对羟基肉桂酸能明显延长单酚酶的迟滞时间,0.2 mmol/L对羟基肉桂酸能使迟滞时间由1.1 min延长至6.2 min。对羟基肉桂酸对二酚酶的抑制作用为混合型抑制,对游离酶的抑制常数和对酶-底物络合物的抑制常数分别为0.29 mmol/L和0.60 mmol/L。  相似文献   

17.
以4-溴-1,8-萘二甲酸酐和甲胺为原料,合成得到一种新的荧光单体4-(N’-甲基-1-哌嗪基)-N-甲基-1,8-萘二甲酰亚胺烯丙基氯化铵(FM)。通过红外光谱、核磁共振及质谱对FM进行了表征。将FM与丙烯酸(AA)、丙烯磺酸钠(SAS)、次磷酸钠共聚制备了含荧光基团的AA-SAS共聚物(FM-AA-SAS)。对该共聚物的荧光性质和阻垢性能进行了系统研究,结果表明:共聚物的荧光强度与其质量浓度呈良好的线性关系,线性相关系数为0.99893,检测下限为0.6566mg/L;采用静态法,当加药质量浓度为15mg/L时对磷酸钙的阻垢率为85.3%,对碳酸钙的阻垢率为86.5%,加药质量浓度为7.5mg/L时对硫酸钙的阻垢率为100%,具有较好的分散氧化铁和稳定锌离子的能力。通过扫描电镜观察发现FM-AA-SAS对碳酸钙垢既有较强的分散作用又具有明显的晶格畸变能力。  相似文献   

18.
采用平皿培养法考察蒈烷-3,4-二醇在水溶液中对一年生黑麦草和油菜根、茎伸长的抑制作用,探讨其作为水基除草剂的应用潜力。结果表明:蒈烷-3,4-二醇微溶于水,可在少量亲水性有机溶剂和表面活性剂作用下配制成浓度大于20 mmol/L水乳液,能够抑制黑麦草和油菜根、茎的伸长,表现与浓度相关的除草活性,对黑麦草的根、茎伸长的半数抑制浓度(IC50)分别达到1.12和1.73 mmol/L,而对油菜根、茎伸长的IC50分别达到1.23和2.12 mmol/L。其除草活性明显高于天然单萜二醇对孟烷-3,8-二醇,而稍低于商业除草剂草甘膦,有望进一步研究开发作为水基植物源除草剂。  相似文献   

19.
Curtisia dentata (CD) is a vulnerable medicinal plant used for the treatment of stomach ailments in South Africa. However, there is a lack of sufficient data on its phytochemical components and medicinal properties. The phytochemical analysis of the extract was estimated using standard assay methods while its antibacterial activity was determined by the agar dilution method against selected bacteria. The antioxidant activity of the extract was done using ferric reducing power, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid (ABTS), nitric oxide (NO), hydrogen peroxide (H(2)O(2)) and lipid peroxidation (LPO). The cytotoxicity assay of the extract was assessed using the brine shrimp lethality test with LC(50) value of 0.302 mg/mL. The antibacterial activity of the extract demonstrated an appreciable broad spectrum activity against the tested bacteria with minimum inhibitory concentration (MIC) ranges between 5000 and 0.5 mg/L. Both phenol and flavonoid concentrations were 14.86 mg tannic acid equivalent/g and 13.64 mg quercetin equivalent/g, respectively. The percentage composition of saponins (13.26) was highest, followed by steroids (1.42), while alkaloids and tannins had the same value of 0.51. Similarly, IC(50) values of the extract against DPPH, ABTS, H(2)O(2), LPO and NO were 0.017, 0.018, 0.159, 0.06 and 0.052 mg/mL, respectively. The reducing power of the extract was found to be concentration dependent. Our data suggest that the 70% ethanol extract from the CD extract has antibacterial and antioxidant properties due to the presence of bio-active compounds and thus support its folkloric use in the treatment of diseases.  相似文献   

20.
采用室内培养皿法,以清水和油菜素内酯作对比,分析不同浓度的苦参碱制剂浸种大麦种子对大麦的种子发芽率、苗高、根长等形态指标,以及叶绿素和可溶性糖含量等的影响。结果表明,苦参碱对大麦种子萌发及幼苗生长有促进作用,且随着苦参碱质量浓度的增大,大麦的种子发芽率、苗高、根长、叶绿素和可溶性糖含量呈先升高后降低的趋势,以100 mg/L处理各指标最好。此外,100 mg/L苦参碱浸种处理对大麦幼苗各项指标的影响与25 mg/L油菜素内酯相似或比25 mg/L油菜素内酯好。  相似文献   

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