外来种喜旱莲子草的克隆生长特性

通过对外来种喜旱莲子草（Alternanthera philoxeroides（Mart．）Griseb）生长指标的测定和分析，研究了它的克隆生长规律，并探讨丁它的觅食行为．在一个生长季节内，喜旱莲子草生物量增加了近30倍，一级葡萄茎分株数增加了近50倍，最长的一级葡萄茎长度增长了近40倍，一级葡萄茎总长度增长了近13倍；一、二、三级葡萄茎上的总分株数增加了近130倍，3个级别匍匍苇总长度增长了近28倍．通过各级葡萄茎个数，葡萄茎总长度和葡萄茎总分株数比较发现，二级葡萄茎比一、二级葡萄苇生长的都要快，而一级葡萄茎的间隔物平均长度远远大于二级和三级葡萄茎．克隆植物的觅食行为与它的克隆生长紧密相连，从觅食行为来看，喜旱莲子草克隆构型随生长季节的变化说明了它对生长季节具有很强的适应性．这种快速克隆生长的特性和对生长季节的适应性有利于喜旱莲子成功入侵新的生境。     

The latest research progress on the prevention of storage pests by natural products: Species,mechanisms, and sources of inspiration

The quality of grains is influenced by storage pests, which are not only spoilers of stored grain, but also vectors of human and animal diseases. Chemical pesticides play an essential role in the cultivation and storage of cereals, however, due to the low degradability and residual toxicity of synthetic pesticides on the environment and non-target organisms, as well as the increasing resistance of target organisms to them, consideration should be given to the development of alternative pest control agents. Compounds isolated from natural sources have emerged as preferred targets for the development of novel insecticidal agents because of their eco-friendliness, safety, and effectiveness. In this review, we primarily focus on the natural product (NPs) control of storage pests. The effective monomer components of NPs and their anti-insect mechanisms were discussed, and natural sources of inspiration and models for insect repellents are described. This review aimed to provide guidelines for the exploitation and utilization of green and efficient natural insecticides.     

Antidementia Effects of Alternanthera philoxeroides in Ovariectomized Mice Supported by NMR-Based Metabolomic Analysis

The crude ethanol extract of the whole plant of Alternanthera philoxeroides (Mart.) Griseb was investigated for its potential as antidementia, induced by estrogen deprivation, based on in vitro antioxidant activity, β-amyloid aggregation inhibition and cholinesterase inhibitory activity, as well as in vivo Morris water maze task (MWMT), novel object recognition task (NORT), and Y-maze task. To better understand the effect of the extract, oxidative stress-induced brain membrane damage through lipid peroxidation in the whole brain was also investigated. Additionally, expressions of neuroinflammatory cytokines (IL-1β, IL-6 and TNF-α) and estrogen receptor-mediated facilitation genes such as PI3K and AKT mRNA in the hippocampus and frontal cortex were also evaluated. These effects were confirmed by the determination of its serum metabolites by NMR metabolomic analysis. Both the crude extract of A. philoxeroides and its flavone constituents were found to inhibit β-amyloid (Aβ) aggregation.     

入侵植物喜旱莲子草预培养土壤对自身及同属本地植物生长的影响及机制

植物-土壤反馈可以在一定程度上阐明入侵植物入侵及维持的机制.通过比较入侵植物喜旱莲子草（Alternanthera philoxeroides）预培养的土壤与本地植物莲子草（Alternanthera sessilis）预培养的土壤对入侵植物喜旱莲子草与本地植物莲子草生长的影响,从土壤肥力、微生物群落及化感物质等角度阐明喜旱莲子草入侵过程中的植物 土壤反馈作用及可能机制,为入侵植物入侵机理的阐明提供理论依据.喜旱莲子草预培养土壤与莲子草预培养土壤对自身及彼此的叶生物量、茎生物量、根生物量和总生物量均无显著影响.喜旱莲子草预培养土壤的碱解氮显著高于莲子草预培养土壤,但是2种土壤肥力对喜旱莲子草以及莲子草的生物量均不存在显著相关.喜旱莲子草预培养土壤经灭菌处理后可以显著地促进莲子草的根生物量、茎生物量及总生物量,显著地抑制莲子草的叶生物量,但对喜旱莲子草的生长无显著影响,表明喜旱莲子草预培养土壤中的微生物群落对莲子草的生长具有一定的抑制作用.喜旱莲子草预培养土壤经添加活性碳处理后对喜旱莲子草与莲子草的生物量均无显著影响,表明喜旱莲子草预培养土壤中的化感物质对莲子草的生长不具有显著作用.     

原子吸收光谱法测定污水中空心莲子草的Pb和Zn

采用原子吸收光谱法测定空心莲子草根、茎、叶中的pb^2＋、Zn^2＋富集量,及其对pb^2＋、Zn^2＋离子的去除速率进行初步研究.结果表明,低浓度时空心莲子草对pb^2＋、Zn^2＋净化能力第1天可以达到50％左右,5天后累积去除率达90％以上,对两种重金属的富集情况：根＞茎＞叶.