极端耐盐碱菌株的筛选及其菌肥对盐碱条件下小麦生长和土壤环境的影响

为获得具有盐碱地改良应用潜力的耐盐碱菌株,将采集于东营盐碱地的土样稀释涂布于pH 9、盐浓度100 g·L-1的Gibbson改良培养基上,共获得18株细菌.通过提高盐浓度、pH值,最终获得在pH 12、盐浓度20%的条件下仍然可以生长的极端耐盐碱菌株N14.对N14进行形态学、生理生化特征和16S rDNA序列分析鉴定,结果表明:菌株N14为马氏芽孢杆菌.盆栽试验结果表明,与盐碱土(CK)相比,N14菌肥可以显著提高小麦的生物量,株高、鲜重、干重分别提高了21.8%、57.9%、41.7%;显著增加小麦叶绿素a、叶绿素b、叶绿素总量,增长率分别为36.4%、20.0%、31.7%;显著提高盐碱土壤中的蔗糖酶、脲酶和碱性磷酸酶的活性,增长率分别为23.2%、68.8%、106.5%;显著提高小麦根系的超氧化物歧化酶、过氧化物酶和过氧化氢酶的活性,增长率分别为109.6%、17.8%、50%;显著减少小麦根系丙二醛的含量,减少率为39.8%.本研究为极端耐盐碱菌的应用提供了一条新思路,为盐碱地的改良提供了一条新途径.     

石灰岩石器使用功效的模拟实验——以重庆巫山玉米洞遗址为例

本文以巫山玉米洞遗址为例,对石灰岩石器进行复制与使用功效的模拟实验,结果表明有些石灰岩在石器打制层面表现出较好的适用性,石灰岩石器在常规的砍砸、切割、挖掘等行为活动中表现出良好的功能实用性和效率。通过实验标本与遗址出土石器的对比分析,我们认为该遗址应存在优选天然毛坯直接使用而形成的“使用石器”,类型主要集中在砍砸器和手镐等重型工具,但二次加工的石器比“使用石器”更为有效耐用;有尖类石器在作用于硬性对象或结构不稳定、受力不均时容易产生残损,与出土有尖类石器较高的残损率相吻合;把手修理在石器使用过程中显得非常必要,为遗址出土石器普遍存在把手修理现象提供了合理解释。     

协同分布式实验2.0 (CDE 2.0):生态学野外研究新方法

全球野外实验网络是近年来兴起的生态学实验方法,产生了“协同分布式实验”(CDE)、“分布式协作实验”(DCE)的野外实验网络和英国生物学记录中心(BRC)的野外观察网络等具体方法,但均存在尺度小、周期短或数据偏差问题.野外实验网络的协议设计应秉持实验优于观察测量、数据数量优于数据质量和尺度优于操作的原则.综合上述方法,本研究提出利用公众科学(citizen science)获得大范围、多尺度和长周期的数据,采用环境因子作为协变量对公众参与者的实验数据集进行验证后,将其作为后验概率与作为主观概率的生态学家实验数据集进行比对,以完成数据有效性验证,克服公众参与者数据质量瑕疵,并提出了相应的统计学模型.讨论了生态学实验数据中应用先验概率、先验与后验概率的逻辑关系以及后验概率发现演化过程新关系的可能性.这种方法更符合统计学采样规范,并增加了大尺度时空的样本量.该方法有望为生态学研究所寻找的一般性理论提供方法支持,新方法可称之为“协同分布式实验2.0”(CDE 2.0).     

黑果枸杞提取物泡腾片的制备及其质量评价

为了解决黑果枸杞中花青素稳定性问题,本文采用Box-Behnken设计对黑果枸杞提取物泡腾片配方进行优化,并对其进行质量评价。采用酸碱混合制粒压片法,通过单因素实验,筛选出片剂所需的辅料:崩解剂、填充剂、润滑剂以及甜味剂。采用响应面试验,结合感官评价进行处方优化,从而确定最优配方:柠檬酸32%、黑果枸杞提取物25%、碳酸氢钠24%、乳糖15%、甜蜜素3%、聚乙二醇6000 1%;对最优配方进行质量评价,各项指标均符合规定,其中花青素含量为8.06 mg/g。该泡腾片表面光滑,泡腾效果好,具有黑果枸杞香气,为实际生产提供理论依据。     

Integrative taxonomy recognized a new cryptic species within Stipa grandis from Loess Plateau of China

Stipa shanxiensis, a cryptic species within Stipa grandis that originated from central and western China, is described based on morphological, genomic, and ecological data from field and common garden experiments. Stipa shanxiensis morphologically resembles S. grandis, although phylogenetically it is closely related to the less morphologically similar Stipa baicalensis and Stipa krylovii. Of the eight significant morphological differences between S. shanxiensis and S. grandis, the two, cauline ligules longer than 2 cm with a filiform apex, and hairs shorter than 0.2 mm on the adaxial surface of the cauline uppermost leaves can be used to distinguish the species. Results from a common garden experiment verified that the two diagnostic characteristics were relatively stable and less morphologically plastic in response to environmental variation. Furthermore, a significant ecological divergence was found between S. shanxiensis and S. grandis, such that the former preferred warmer and more humid climates, and their predicted distribution was generally separated. Taken together, our results highlight that the integrative taxonomic approach was valuable for recognizing a new cryptic species in Stipa. In particular, we find that common garden experiments involving the effects of growth stage and characteristic position helped to morphologically diagnose cryptic species. These findings may also facilitate our understandings of ecological adaption and phenotypic plasticity in response to environmental change.     

矮珍珠硝酸盐转运蛋白基因GeNRT2.1的克隆和功能研究

硝酸盐转运蛋白（nitrate transporter,NRT）是植物识别、吸收和转运硝酸盐的关键蛋白,对促进作物根系发育、提高产量具有重要作用。通过筛选水生植物,利用NRT蛋白的保守区设计简并引物,并通过PCR和RACE技术,首次从矮珍珠（Glossostigma elatinoides）中克隆得到GeNRT2.1基因。进化分析结果表明,GeNRT2.1与烟草NRT2.1在进化关系上距离最近。qRT-PCR结果表明,GeNRT2.1在矮珍珠根中表达量最高,其次是叶和茎,此外,低浓度硝酸盐（0.5 mmol·L^-1）处理后,GeNRT2.1在根、叶、茎中的表达量分别是高浓度硝酸（2 mmol·L^-1）处理后的1.89、1.93和2.07倍。功能互补实验发现,GeNRT2.1能使缺陷型酵母Δynr恢复生长,具有硝酸盐转运蛋白的功能。通过丰富NRT基因资源,以期为培育氮肥高效利用转基因作物,发展绿色农业,保证我国的粮食安全和环境安全提供理论依据。     

血立停胶囊对早孕大鼠RU486药流后子宫收缩的实验研究

目的:研究血立停胶囊对早孕大鼠Ru486药物流产后对子宫平滑肌收缩频率、收缩幅度及活动力变化的影响,旨在探讨血立停胶囊治疗药物流产后出血的作用机制。方法:选择妊娠Wistar大鼠,随机分为6组,即对照组,米非司酮组,大剂量血立停组,小剂量血立停组,催产素组,止血敏组。于妊娠第7天,开始相应处理,妊娠第14天分别监测以下指标后处死:在体子宫平滑肌收缩力,收缩幅度、收缩频率。结果:大剂量血立停可明显增强大鼠在体子宫平滑肌活动力、提高子宫平滑肌收缩频率、收缩幅度,与对照组比较差异有显著性(p<0.05)。结论:血立停胶囊可增强大鼠子宫平滑肌兴奋性,从而起到对药物流产后阴道出血的治疗作用。     

‘Ten Years After’—a long-term settlement and bioerosion experiment in an Arctic rhodolith bed (Mosselbukta,Svalbard)

Rhodolith beds and bioherms formed by ecosystem engineering crustose coralline algae support the northernmost centres of carbonate production, referred to as polar cold-water carbonate factories. Yet, little is known about biodiversity and recruitment of these hard-bottom communities or the bioeroders degrading them, and there is a demand for carbonate budgets to include respective rates of polar carbonate build-up and bioerosion. To address these issues, a 10-year settlement and bioerosion experiment was carried out at the Arctic Svalbard archipelago in and downslope of a rhodolith bed. The calcifiers recorded on experimental settlement tiles (56 taxa) were dominated by bryozoans, serpulids and foraminiferans. The majority of the bioerosion traces (30 ichnotaxa) were microborings, followed by attachment etchings and grazing traces. Biodiversity metrics show that calcifier diversity and bioerosion ichnodiversity are both elevated in the rhodolith bed, if compared to adjacent aphotic waters, but these differences are statistically insignificant. Accordingly, there were only low to moderate dissimilarities in the calcifier community structure and bioerosion trace assemblages between the two depth stations (46 and 127 m), substrate orientations (up- and down-facing) and substrate types (PVC and limestone), in that order of relevance. In contrast, surface coverage as well as the carbonate accretion and bioerosion rates were all significantly elevated in the rhodolith bed, reflecting higher abundance or size of calcifiers and bioerosion traces. All three measures were highest for up-facing substrates at 46 m, with a mean coverage of 78.2% (on PVC substrates), a mean accretion rate of 24.6 g m^?2  year^?1 (PVC), and a mean bioerosion rate of ?35.1 g m^?2 year^?1 (limestone). Differences in these metrics depend on the same order of factors than the community structure. Considering all limestone substrates of the two platforms, carbonate accretion and bioerosion were nearly in balance at a net rate of ?2.5 g m^?2 year^?1. A latitudinal comparison with previous settlement studies in the North Atlantic suggests that despite the harsh polar environment there is neither a depletion in the diversity of hard-bottom calcifier communities nor in the ichnodiversity of grazing traces, attachment etchings and microborings formed by organotrophs. In contrast, microborings produced by phototrophs are strongly depleted because of limitations in the availability of light (condensed photic zonation, polar night, shading by sea ice). Also, macroborings were almost absent, surprisingly. With respect to carbonate production, the Svalbard carbonate factory marks the low end of a latitudinal gradient while bioerosion rates are similar or even higher than at comparable depth or photic regime at lower latitudes, although this might not apply to shallow euphotic waters (not covered in our experiment), given the observed depletion in bioeroding microphytes and macroborers. While echinoid grazing is particularly relevant for the bioerosion in the rhodolith bed, respective rates are far lower than those reported from tropical shallow-water coral reefs. The slow pace of carbonate production but relatively high rates of bioerosion (both promoted by low carbonate supersaturation states in Arctic waters), in concert with high retention of skeletal carbonates on the seafloor and no calcite cements forming in open pore space created by microborers, suggest a low fossilisation potential for polar carbonates, such as those formed in the Mosselbukta rhodolith beds.     

三角梅苞叶色彩参数和色素含量分析及蓝色转基因受体的筛选北大核心CSCD

三角梅作为重要的观赏植物颜色繁多,但缺乏稀有的蓝色。为筛选适合的蓝色转基因受体,明确不同品种三角梅苞片吸收利用DHM(二氢杨梅素)合成甜菜色素途径竞争产物(类黄酮色素)的潜在能力,该研究对红色、白色、黄色和紫色4大花色6个品种的三角梅苞片进行离体诱导培养,测定诱导培养后苞片色彩参数及色素含量变化,并进行相关性分析。结果显示:(1)三角梅苞片红绿色相值(a*)是决定苞片呈色的主要色彩参数,其色彩主要由甜菜色素和黄酮类色素决定,并以甜菜红素的影响最大。(2)除白色品种三角梅苞片中黄酮类色素含量大于甜菜色素含量外,其余品种苞片发育中甜菜色素含量均呈上升趋势,黄酮类色素呈下降趋势。(3)甜菜色苷含量与苞片a*值呈显著正相关关系,同时与苞片黄蓝色相值(b*)呈显著负相关关系;总黄酮含量与苞片b*值呈显著正相关关系,与苞片a*值呈极显著负相关关系。(4)经DHM体外诱导培养后,苞片总黄酮含量及占比在4个品种三角梅(‘新加坡大白’、‘宝老橙’、‘中国丽人’、‘黄蝶’)中明显升高,但各品种苞片总甜菜色素含量及占比均下降,并以‘新加坡大白’苞片中总黄酮含量上升幅度最大(65.77%),含量占比变化(增加26.91%)也为6个品种中最大。(5)灰色关联度综合分析显示,白色品种‘新加坡大白’与灰色关联度分析拟定的参考品种关联度最高(0.7444),表明三角梅品种中‘新加坡大白’可考虑作为蓝色转基因三角梅的受体品种。