不同浓度沼液对日光温室漂浮式栽培空心菜(Ipomoea aquatica)生长和品质的影响

以鸡粪沼液为肥源,通过日光温室内沼液漂浮式栽培试验,研究不同浓度沼液对空心菜生长和品质的影响。结果表明：在3%~5%浓度范围内,鸡粪沼液能显著提高空心菜的叶绿素含量、生物量和Vc含量,降低亚硝酸盐含量。阶段性添加沼液2%→3%→4%→5%浓度处理和一次性添加沼液3%、5%浓度最适宜空心菜的生长,叶绿素含量和生物量均显著高于对照组;阶段性添加沼液2%→3%→4%→5%浓度处理Vc含量最高,为385.2 mg·kg-1,显著高于对照组;各处理空心菜的亚硝酸盐含量均低于我国无公害蔬菜亚硝酸盐含量限量标准（以NaNO2计≤4.0 mg·kg-1）。沼液漂浮式栽培对提高蔬菜的生物量和品质,减少传统营养液和化肥的使用量,解决沼气工程中大量沼液的消纳难题具有重要意义。

台湾海峡西部海区带鱼Trichiurus haumela(Forsk■l)的生殖力

分布于黄、渤海、东海和南海的带鱼Trichiurus haumela (Forsk(?)),是我国海产鱼类中很重要的捕捞对象之一。为了探索带鱼种群数量变动,开展带鱼生殖力的研究,阐明与补充群体关系至为密切的环节,不仅具有理论上的意义,而且可供渔业现代化管理的参考。关于带鱼生殖力的研究,国内外虽有一些报道,但我国南方带鱼种群生殖力的研究却很少,仅在综合调查报告中有些零星的记载。因此,作者对台湾海峡西部海区带鱼生殖力指标及其变动规律进行了分析研究。

水蕹菜(Ipomoea aquatica)对含银废水的净化功能研究

本文通过对水蕹菜净化含银废水的室内外静、动态试验研究得出:(1)水蕹菜对离子态银(Ag^+)的去除速率高于对络合态银[Ag(S_2O_3)_2]^(3-)的去除速率即 K_(Ag)+>K[Ag(S_2O_3)_2]^(3-);(2)水蕹菜对银的净化率 R 与污水停留时间 t 呈指数函数关系(R=Ae^(B,t),A、B为常数,B<0),其表面去除负荷 P_S 则与 t 呈幂函数关系(P_S=At^B,B<0);(3)试验证明水蕹菜是生物净化含银废水的优良品种之一。

Application of iron and silicon fertilizers reduces arsenic accumulation by two Ipomoea aquatica varities

A 45 d pot experiment was conducted to examine the effects of silicon fertilizer or iron fertilizer on the growth of two typical Ipomoea aquatica cultivars（Daye and Liuye） and arsenic（As） accumuation of Daye and Liuye grown in As-contaminated soils at different As dosage levels. The results showed that the application of these two fertilizers generally enhanced the growth of the plants, which may be partly attributable to the reduction in As toxicity. The addition of these two fertilizers also significantly reduced the uptake of As by the plants though the iron fertilizer was more effective, as compared to the silicon fertilizer. The accumulation of As in shoot portion was weaker for Daye than for Liuye. The research findings obtained from this study have implications for developing cost-effective management strategies to minimize human health impacts from consumption of As-containing I. aquatica.

Research Progress on Application of Ipomoea aquatica Floating Bed in Eutrophication Water

Research progresses on growth characteristics,application effect and optimization technology of I. aquatica floating bed were reviewed;its application problems in eutrophication water were discussed,and its application prospect was forecasted.

Interactions between Ipomoea aquatica and Microbial Populations

[Objective]This paper was to research the water purification mechanism of Ipomoea aquatica and its correlation with algae and rotifer. [Methods]Taking I. aquatica as the test material,Chlorella vulgaris,Scenedesmus obliquus,Microcystis aeroginosa and rotifer Adineta vaga with different densities were added to the hydroponics nutrients solutions of I. aquatica by the hydroponic ecological simulation method. The growth characteristics of I. aquatica,changes of microbial populations and the consumption status of nutrients in the nutritional solution were determined. And the interactions between the plant and the microbial populations were researched. [Results]When I. aquatica seedlings grew to a certain stage,growth of principal root stopped; while the lateral roots emerged greatly; and the nutrition absorption efficiency enhanced. As the inoculation concentration of C. vulgaris increased,root length of I. aquatica increased relatively great due to the competition for nutrients. The competition and allelopathy of M. aeroginosa and S. obliquus restricted the development of root system of I. aquatica. The grazing pressure of Chlorella vulgaris had little effects on M. aeroginosa,but restricted the rapid growth of S. obliquus. [Conclusions]This research provided data support for the application of fish-shrimp-vegetable aquaculture system.

铁碳内电解耦合蕹菜(Ipomoea aquatica)对黑臭污水脱氮效果的研究

构建了铁碳内电解耦合蕹菜技术体系,用于原位净化河道黑臭污水,采用单因素模拟实验,探究耦合体系植株密度、铁碳填料用量和陶粒用量对黑臭污水脱氮效果的影响规律.结果表明,在植株密度为80株/m 2、铁碳填料用量为18 g/L和陶粒用量为52 g/L的适宜组合下,处理22 d后,TN和NH4^+-N的去除率分别为74.1%和99.6%,其质量浓度分别稳定在(13.65±1.24)mg/L和(0.18±0.04)mg/L.水体微生物丰度和多样性有了显著提高,主要优势细菌门是Proteobacteria、Firmicutes和Bacteroidetes,主要优势细菌属为Pseudomonas、Escherichia-Shigella和Diaphorobacter,微生物群落演化更适宜脱氮.耦合体系通过协同作用净化水质,其作用过程包括:铁碳内电解产生质子[H]和Fe^2+提供电子促进自养反硝化、蕹菜根际泌氧促进微生物硝化、陶粒生物膜与根际微生物之间的硝化反硝化作用、陶粒吸附氮.该研究为采用铁碳内电解耦合挺水植物净化河道黑臭污水提供了依据.

Rotula aquatica Lour. inhibits growth and biofilm formation of clinically isolated uropathogenic Escherichia coli

Objective:To evaluate the anti-bacterial and anti-biofilm activity of ethyl acetate fraction of Rotula aquatica Lour.(EFRA)against clinically isolated uropathogenic Escherichia coli.Methods:In vitro antibacterial and anti-biofilm studies were employed.The antimicrobial activity of EFRA was assayed by the well diffusion method.The minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of the active fraction were determined by Resazurin method.The time-kill kinetic assay,acridine orange-ethidium bromide staining,propidium iodide uptake assay,and scanning electron microscopic(SEM)analysis were done to evaluate the efficacy of EFRA in killing uropathogenic Escherichia coli.The anti-biofilm activity was determined by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2 H-tetrazolium-bromide(MTT)assay and specific biofilm formation assay.Results:The well diffusion assay of EFRA showed a very clear zone of inhibition against Escherichia coli BRL-17.The MIC and MBC of EFRA were 2.5 mg/m L and 5 mg/m L,respectively.The time-kill kinetic assay,fluorescence microscopic analysis,propidium iodide uptake assay,and SEM analysis displayed the effect of EFRA in killing the bacteria.The MTT assay and specific biofilm formation assay showed that EFRA prevented the formation of biofilms.Conclusions:The results of the present study confirm that EFRA could prevent bacterial growth and inhibit its biofilm formation.

Quantitative variation of bioactive phyto compounds in ethyl acetate and methanol extracts of Pergularia daemia(Forsk.)Chiov.

Dear Editor： Pergularia daemia Forsk （Asclepiadaceae） is a perennial twining herb commonly known as veliparuthi in Tamil. The plant has anthelmintic, laxative, antidiabetic, hepatoprotective and anti-inflammatory activities. The pharmacological properties of this plant come from bioactive phytochemicals such as alkaloids, triterpenes, saponins and flavonoids. Phytochemically, the plant has been investigated for the presence of cardenolides, alkaloids, saponins and steroidal compoundst. In the present study, we developed a rapid method for identification and quantitative determination of putative phyto compounds in the crude extracts of ethyl acetate and methanol from whole plant of Pergularia daemia.

小白菜和空心菜体内^(125)I赋存形态探讨及含量分析

利用放射性125I初步分析了外源无机碘被小白菜和空心菜吸收后在植物体内的形态分布及相对含量,探讨通过培育含碘蔬菜,实现人体自然补充碘的可行性。通过对125I的碘化物的检测,结果显示,碘在小白菜和空心菜中以无机碘、有机碘以及残态碘共存。在小白菜植株体内,无机碘含量最高,占总碘量的42.48%,有机碘占7.91%,其余为残态碘;在空心菜植株体内,残态碘、无机碘和有机碘量占总碘量依次为64.97%、28.36%和6.66%。小白菜和空心菜中,无机碘主要以I-、IO3-和I2形式存在,以I-为主;有机结合碘主要以蛋白质结合碘为主,小白菜体内蛋白质结合碘占总碘的22.43%,而空心菜体内蛋白质结合碘占总碘的8.68%;核酸结合碘含量其次,多糖结合碘量最少,分别为0.78%和0.40%。以上结果表明,小白菜和空心菜可以富集环境中的碘,可以作为含碘蔬菜进行培育。

国产“水山姜”的分类学研究——来自核糖体DNAITS区序列的证据

用直接测序法对国产黑果山姜Alpinianigra (Gaertn.)Burtt以及“水山姜Alpiniaaquatica(Koen.)Rosc .”的核糖体DNA中的内转录间隔区 (ITS)序列进行了测定 ,结果显示两者序列完全一致 ;ITS 1长度为 1 78bp,ITS 2长度为 2 32bp,5 8S编码区长度为 1 64bp ,GC含量为56 9%。形态学特征结合DNA分子证据 ,认为《中国植物志》

蕹菜的DAPI显带核型

利用一种新的DAPI显带技术分析了蕹菜染色体的DAPI带型及其异染色质的分布,建立了类似于G带的蕹菜DA PI带模式图,为蕹菜的细胞遗传学研究、育种和资源的开发利用提供帮助。

STUDIES ON ION BEAM APPLICATION TO IMPROVE AQUATIC MACROPHYTE REMEDIATION CAPACITY IN EUTROPHIC WATERS

Using ion beam biotechnology in combination with soil-less plant cultivation on artificial substratum (floating beds), the experiments were conducted with Ipomoea aquatica Forsk. Plants were attached to floating-beds which were placed on the surface of artificially nutrient-enriched tank water, in order to study the purification and remediation efficiency of ion beam-treated I. aquatica cultivars. The results show that N + ion beams with 25keV energy and dosages of 0, 2.6, 3.9, 5.2, 6.5, 7.8, 9.1×10 13N +(ions)/cm 2 affected I. aquatica dry seeds differently, with the dose of 3.9×10 13N + (ions)/cm 2 improving effectively the performance as expressed by various biological indices. After ion beam application, I. aquatica cultivars grew well in nutrient-enriched water bodies, increasing the growth of leaves and stem, number of leaves, length and area of roots, plant height, and weight more remarkably than observed in the control. The net removing rates of TN, TP were as high as 75% and 82%, respectively. Especially under the dose of 3.9×10 13N +(ions)/cm 2, the net removing rates of TN, TP were highest, for 77% and 85%, respectively. It was proved that ion beam application improves phytoremediation and may be used to purify nutrient rich water bodies.

Heavy Metal Accumulation Potential of Some Wetland Plants Growing Naturally in the City of Kolkata, India

Freshwaters are not only used locally in many developing countries but they are often over exploited for domestic purposes, agriculture and disposal of industrial wastes which result in an overload of excess nutrients, harmful chemicals and heavy metals. Plant species together with sediments and water samples collected from eleven aquatic water bodies in the vicinity of industrial units in Kolkata were studied for their potential to uptake Pb, Cd and Cr under field conditions. Cd and Cr concentrations in the sediments were higher than background values considered to be toxic. Alternanthera philoxeroides and Eichhornia crassipes were the two invasive species present, with the former being more widely distributed. Among native plants, Ipomoea aquatica was the most abundant. Metal uptake in the plants differed among species, tissues and sites. Pb and Cd accumulation in root tissues for all plants in most sites suggested an exclusion strategy for metal tolerance. Since I. aquatica is widely consumed in many parts of SE Asia, its metal content should be checked before use since it was found to efficiently translocate both Pb and Cd from roots to shoots. The potential of A. philoxeroides as a metal excluder needs to be explored further since it translocates less to its shoots as compared to E. crassipes and I. aquatica.

Green Synthesis of CuO Nanoparticles Using Leaf Extract of Catha edulis and Its Antibacterial Activity

Copper oxide nanoparticles(CuO NPs)have attracted huge attention due to catalytic,electric,optical,photonic,and antibacterial activity.The use of plant leaf extracts in the biosynthesis of nanostructured materials is an eco-friendly,non-toxic and cost effective approach.Hence,this study aims to provide an updated survey of the main green synthesis method of CuO NPs using leaf extract of Khat,its characterization and studies on antibacterial activities.The synthesis of CuO NPs was done by reducing 1 mM CuSO4?5H2O with 2%(m/v)aqueous leaf extract of Khat under optimum conditions(pH=11).The formation of CuO NPs has been confirmed first by the color change from colorless to light green and then to greenish yellow.The kinetics of the reaction was studied using UV-Visible(UV-Vis)spectrophotometer that showed surface plasmon resonance at 333 nm.The CuO NPs exhibit antimicrobial activity against two human pathogens viz.Salmonella typhimurium and Escherichia coli with an average zone of inhibition of 12.5 mm and 8 mm,respectively.Therefore,the current study reveals a convenient utilization of Catha edulis extract as a reducing agent for the successful synthesis of CuO NPs through a green synthesis method to obtain significantly active antibacterial material.

硫酸化制备圆苞车前子低黏多糖及其结构表征和抗氧化活性研究

圆苞车前子(Plantago ovata Forsk)具有润肠通便,辅助消化等功效,但因高黏特性无法对其多糖成分展开系统研究。因此,本研究以圆苞车前子为研究对象,采用氯磺酸-吡啶法制备低黏性圆苞车前子硫酸化多糖(POFP-S),POFP-S经DEAE-650M和Superdex 200凝胶分离纯化获得一种中性和一种酸性均一多糖(POFP-S1、POFP-S2),其中POFP-S1主要由鼠李糖、阿拉伯糖、木糖和葡萄糖组成,分子量为3556 kDa,硫酸基取代度为0.364;POFP-S2由阿拉伯糖和木糖组成,分子量为833.7 kDa,硫酸基取代度为1.080;红外光谱(FT-IR)中典型的硫酸基吸收峰证实了硫酸化修饰的成功。X射线衍射(XRD)及刚果红实验结果显示,POFP-S2是具三螺旋结构的,晶体与非晶体结构共存的特殊多糖,也表明硫酸化修饰未影响圆苞车前子多糖的立体结构。采用DPPH、ABTS及OH等自由基清除实验,考察了硫酸化多糖的体外抗氧化活性,发现POFP-S1和POFP-S2具有显著的抗氧化活性。研究结果将为进一步研究圆苞车前子多糖的结构与活性提供文献依据,以及开发具有潜力的药食同源产品提供依据,并为高黏性多糖的研究提供理论参考。

密度与肥料对泽泻产量的影响

[目的]探究密度和肥料的不同配比泽泻产量及其互作影响,筛选出科学的密肥水平,为泽泻规范化栽培提供理论依据和实践经验。[方法]以川泽泻为试验材料,采用4因素5水平二次正交旋转组合设计进行大田试验,建立密度、氮肥、磷肥、钾肥与泽泻产量的效应函数。[结果]建立的二次回归方程R^(2)=0.9097,所建立的数学模型拟合程度较为可靠。各因素对泽泻产量的影响为密度>氮肥>钾肥>磷肥,其中密度和肥料的互作效应达显著水平。根据统计频数选优,得到泽泻目标产量大于3300 kg/hm^(2)的最优农艺措施为密度14.69万~15.08万株/hm^(2)、氮肥219.10~234.50 kg/hm^(2)、磷肥124.80~150.00 kg/hm^(2)、钾肥152.55~179.55 kg/hm^(2)。[结论]合理的密度和肥料施用量均能有效提高泽泻产量,以密度增产效果最佳,氮肥次之,钾肥和磷肥的增产效果较小,在保障密度和氮肥的基础上,配合合理的磷钾肥能达到泽泻高产目标。

鱼菜共生系统浮床覆盖率对金鲫摄食率的影响

为研究金鲫-水蕹菜鱼菜共生系统对金鲫摄食率的影响,分别设置水蕹菜浮床覆盖率为0(A组,对照组)、30%(B组)和50%(C组)3组养殖系统,每组3个重复,每5 d作为1个摄食率周期,计算金鲫摄食率。在试验第25天取水样,检测水体总氨氮(TAN)、亚硝酸盐氮(NO2--N)和硝酸盐氮(NO3--N)等水质指标。结果显示,第1期、第2期,A、B、C各组摄食率差异不显著(P>0.05);第3期,摄食率开始呈现C组>B组>A组的趋势(P>0.05);第4期,C组摄食率显著大于A、B两组(P<0.05),B组大于A组,但差异不显著(P>0.05);第5期,各组间摄食率均存在显著差异,C组>B组>A组(P<0.05)。其中第5期,TAN浓度C组>B组>A组(P<0.05);NO2--N浓度和NO3--N浓度均为C组>B组>A组(P>0.05)。鱼体质量增长率及特定生长率B、C两组显著高于A组(P<0.05),C组菜长增长率显著高于B组(P<0.05)。试验结果表明,各系统稳定后,鱼菜共生系统更有利于提高金鲫摄食率,并且50%浮床覆盖率系统更有利于提高金鲫摄食率。

移栽期和密度对泽泻干物质生产及产量的影响

为研究移栽期和密度对泽泻干物质生产和产量的影响,于2021年在四川宜宾市兴文县僰王山镇开展大田试验。试验采用两因素随机区组设计,因素1为移栽期(X):8月17日(X1)、8月27日(X2)、9月6日(X3);因素2为移栽密度(Y):12.0万株/hm^(2)(Y1)、13.5万株/hm^(2)(Y2)、15.0万株/hm^(2)(Y3),测定泽泻不同生育时期干物质质量及产量。结果表明:移栽期和密度对泽泻不同时期的干物质积累及产量形成均有显著或极显著的调控效应,随移栽期推迟和密度增大,泽泻干物质质量和产量呈先增大后减小的趋势。生育前期,以X1的泽泻干物质积累较好,移栽后35、50 d分别比X2、X3的群体干物质质量高12.18%/28.15%、5.43%/12.61%;在中后期则是X2的各器官干物质积累量较高,产量较X1、X3分别高9.53%、10.70%。不同密度处理下单株干物质质量大小依次为Y1、Y2、Y3,群体干物质质量在全生育期以Y2的最大,主要表现在各器官干物质累积量的协同增大,产量最优,较Y1、Y3分别高13.36%、7.63%;而密度过大、过小均不利于群体物质生产,导致产量不高。综合而言,以8月27日移栽结合13.5万株/hm^(2)移栽密度,泽泻干物质积累最优,产量最大,达2 524.01 kg/hm^(2)。

特色农产品产业视角下博白蕹菜网络营销研究

加强网络营销是培育特色农产品产业的重要方式。博白蕹菜产业目前虽然发展形势良好,但在网络营销中还存在着产品品牌效应不足、价格便宜低廉、营销渠道不畅及促销效果不佳等问题。因此,要利用现代新媒体手段进行网络营销,加强产品特色IP建设、进行客户价值定价、构建立体营销渠道、积极开展多种促销,以促进博白蕹菜产业发展壮大。