茶园间作芳香植物罗勒和紫苏对茶园生态系统影响的研究

通过茶园间作芳香植物研究其对茶园害虫和天敌种群数量、土壤养分状况、茶树生长及茶叶生化成分等的影响,分析间作芳香植物对幼龄茶园的生态综合调控效果。幼龄茶园间种芳香植物能减少小贯小绿叶蝉和绿盲蝽的数量,增加茶园中瓢虫、草蛉、寄生蜂和蜘蛛等天敌的数量;芳香植物间作区土壤中铵态氮、有效磷和速效钾的含量高于绿肥间作区和对照;茶园间作芳香植物能在一定程度上促进茶树生长、培养幼龄茶园的树势和树冠、增加茶叶产量。茶园间作芳香植物能减少茶叶中茶多酚和咖啡碱含量,提高可溶性糖和儿茶素含量,改善茶叶品质。可见茶园间作芳香植物是一种具有较好生态效益的茶园栽培管理模式,能促进生态茶园的发展。     

人工浮岛种植水生植物对包头南海湿地水质净化效果研究

【目的】解决包头南海湿地氮磷等营养元素富集的问题,提升包头南海湿地的水质。【方法】于2017年7—9月,在包头南海湿地构筑了一段由3种水生植物单独或混合种植的人工浮岛,并对浮岛的水质进行跟踪监测。【结果】经过92 d的试验处理,风车草对TN的去除效果最好,去除率为36.02%,可以使水体中TN质量浓度提高到地表水Ⅴ类标准;风车草+水葱+千屈菜对TP的去除效果最好,去除率为41.61%,可以使水体中TP质量浓度从地表水Ⅴ类标准提高到Ⅳ类标准;对CODcr去除效果最好的是风车草+水葱+千屈菜,去除率为27.01%。对浮游藻类抑制效果最好的是风车草,可以有效抑制水华束丝藻。【结论】混合植物人工浮岛比单一型人工浮岛去除氮磷等有机物的效果要好,尤以风车草、水葱、千屈菜3种植物混合组成的人工浮岛对氮磷等有机物的效果最好。风车草、水葱、千屈菜可以作为包头南海湿地水体富营养化防治的浮岛栽培植物来进行推广应用。     

Relationship of Icelandic cattle with Northern and Western European cattle breeds,admixture and population structure

ABSTRACT

Icelandic cattle is believed to have been brought from Norway during the settlement of Iceland around AD 870-930. Previous research on genetic relationships has indicated that Icelandic cattle is most related to northern Nordic indigenous breeds. Using single nucleotide polymorphism genotype data from Icelandic cattle and 29 Northern and Western European cattle breeds, we studied relationships and admixture among these breeds, and assessed population structure in Icelandic cattle. Population structure analysis through principal component analysis, estimation of ancestry, and analysis of patterns of population splitting and mixing revealed that Icelandic cattle are most related to three Finncattle breeds (Eastern, Northern and Western Finncattle), and Swedish Mountain cattle. Icelandic cattle has very low levels of admixture. We observed very limited population structure in Icelandic cattle. The observed structure was due to variable sire contributions. Over 1000 years of almost complete isolation has made Icelandic cattle highly genetically distinct from other cattle breeds.     

园林植物春季最佳观赏期调查研究

目前,由于缺乏准确的园林植物最佳观赏期的资料,导致优秀的规划设计方案难以落到实处,园林景点建成之后景观效果大打折扣。针对以上问题,作者采用实地调查观测的方法对园林植物春季最佳观赏期和最佳观赏顺序进行了研究。记录整理典型地点园林植物的最佳观赏期和最佳观赏顺序,为园林规划设计、植物配置和养护管理提供科学的参考依据。     

抚育间伐对燕山北部山区山杨林物种多样性的影响

为了了解抚育间伐对燕山北部山区山杨林物种多样性的影响,对山杨林抚育间伐前后的物种多样性进行了调查和分析,结果表明:抚育后林地草本植物的物种多样性高于未抚育林地,抚育间伐林地草本植物的Patrick指数、Margarlef指数、Simpson指数和Shannon-Wiener指数分别为35.0、6.13、0.89和2.76,未抚育样地分别为29.0、4.90、0.32和1.91;抚育林地灌木的Patrick指数、Margarlef指数、Simpson指数和Shannon-Wiener指数分别为9.0、1.41、0.43和0.98,未抚育林地则分别为8.0、1.48、0.68和1.51,除Patrick指数外,抚育林地的其他多样性指数都低于未抚育林地;抚育间伐使乔木层优势种的优势更为明显。由此得出结论,抚育间伐对山杨林的物种多样性有明显影响,但草本、灌木与乔木对抚育间伐的响应有所不同。     

Analysis on Genetic Diversity and Phyletic Evolution of mtDNA Cytb Gene in Zhongdian Yak

In order to investigate the genetic diversity and the origin of evolutionary relationship of Zhongdian yak,we analyzed the complete sequence of 15 individuals Cytb gene,its sequence polymorphism was analyzed,and the phylogenetic tree was constructed.The results showed that the length of the nucleotide sequence were 1 140 bp,with nucleotide frequencies of 26.3%,31.8%,13.1% and 28.8% for T,A,G and C,respectively.Three haplotypes were identified of 15 individuals,with 3 polymorphic sites,including two conversions,one transversion,haplotype diversity was 0.2571 and nucleotide diversity was 0.00035.Phylogenetic analysis suggested that Zhongdian yak and Bos mutusc clustered firstly,then gathered with Bison bison,which indicated that there were high genetic similarity and closer genetic relationship,genetic similarity with other cattle genus was relatively low.Combining with the proof of molecular biology and paleontology,the result supported the point that Bos grunniens and Bos mutus were classified as an alone genus in Bovinae.     

In Vitro Evaluation of the Effects of Selected Plants on the Growth of the Mycelial Form of Histoplasma capsulatum Variety farciminosum in Ethiopia

Epizootic lymphangitis is prevalent in equines in Ethiopia, causing remarkable economic and welfare impacts but often neglected. Lack of effective treatment contributed to its continued occurrence, and hence, search for an effective treatment should be considered a priority area to minimize its impacts. Previous ethnobotanical studies have reported that Curcuma longa, Phytolacca dodecandra, and Datura stramonium were used to treat cutaneous fungal infections and reduce their incidence. The treatment effects of these plants against epizootic lymphangitis should be studied. The in vitro growth inhibitory effects of methanol extracts of the root of C. longa, berry of P. dodecandra, and leaf of D. stramonium were evaluated. Histoplasma capsulatum var farciminosum was isolated from clinical cases of epizootic lymphangitis in carthorses in central Ethiopia. The nested polymerase chain reaction was used to confirm the identity of the isolates. Serial twofold dilutions of the extract of berries of P. dodecandra and leaves of D. stramonium were done in sterile water, whereas dilution of the extract of roots of C. longa was done in dimethylsulphoxide. The effects of the plants on the growth of Histoplasma capsulatum var farciminosum were assessed by agar dilution assay. Culture media with no antifungal agent and media containing ketoconazole served as negative and positive control, respectively. The methanol extract of C. longa showed inhibitory effects at concentrations ranging from 0.07 to 5 mg/mL. Similarly, the methanol extract of P. dodecandra showed growth inhibitory effects at concentrations ranging from 0.156 to 5 mg/mL. That is, the growth inhibitory concentration of C. longa was 0.07 mg/mL, whereas that of P. dodecandra was 0.156 mg/mL. In contrast, D. stramonium showed no inhibitory effect. This preliminary observation showed that methanol extracts of C. longa and P. dodecandra showed inhibitory effects on the growth of Histoplasma capsulatum var farciminosum requiring further repeated in vitro evaluation so as to generate adequate evidence, which would justify in vivo trials.     

皖北石灰岩山地不同植被恢复模式对植物群落物种组成及多样性的影响

通过研究皖北石灰岩山地生态系统的植被群落,分析不同植被恢复群落的组成、结构、多样性和生活型组成,进而阐明石灰岩山地生态系统植被恢复模式对群落结构特征以及植物物种多样性的影响。结果表明:研究区有54种植物,隶属26科54属。侧柏(Platycladus orientalis)+构树(Broussonetia papyrifera)人工混交林有植物种类16科26种,分别占总数的61.5%和48.1%。酸枣(Ziziphus jujuba var.spinosa)+牡荆(Vitex negundo var.cannabifolia)灌丛和荩草(Arthraxon hispidus)+牡荆草灌丛植物种类分别为32和33种,分别占调查总物种数的59.3%和61.1%。不同植被恢复群落生活型也有差异。侧柏+构树人工混交林群落高位芽植物占优势,而酸枣+牡荆灌丛和荩草+牡荆草灌丛则以地面芽植物所占比例较大。分析表明,多样性指数、均匀度指数和优势度指数均表现为侧柏+构树混交林>酸枣+牡荆灌丛>荩草+牡荆草灌丛,但物种丰富度表现为荩草+牡荆草灌丛>酸枣+牡荆灌丛>侧柏+构树混交林。Sörensen较高值出现在酸枣+牡荆灌丛与侧柏+构树混交林和荩草+牡荆草灌丛之间,侧柏+构树混交林与荩草+牡荆草灌丛Sörensen多样性值较低。研究结果表明,石灰岩山地独特的地貌特征和人工植被恢复对植物群落组成、多样性及其生活型组成产生重要影响。     

基于nSSR和cpDNA序列的城步峒茶群体遗传多样性和结构研究

采用简单重复序列标记(nSSR)与叶绿体DNA序列(cpDNA)分析技术,对城步峒茶群体进行了遗传多样性、遗传结构和遗传分化等研究。结果表明,15对nSSR引物在参试81份资源中共获得142个等位位点,平均每对引物9.47个,城步峒茶群体的观测杂合度(Ho)、期望杂合度(He)和Nei期望杂合度(Nei)分别为0.49、0.62和0.62,具有较高的遗传多样性。Structure分析将79份峒茶资源分成3个类群,但各类群的遗传背景较为复杂,没有明显的群体结构。F检验表明,城步峒茶群体的近交系数F_IS为正值(F_IS=0.177 5),群体间的遗传分化系数F_ST较小(F_ST=0.034 5),分化程度较低,基因流Nm较高(Nm=7.01)。3对cpDNA引物分别获得了473 bp(rbcL)、704 bp(matK)和320 bp(psbH-trnA)的片段序列,变异位点占总位点的比例分别为0.42%、0.71%和1.25%。将3个序列依次拼接,共产生了9个单倍型,单倍型数由多到少的居群依次为TXZ(6)、DZC(4)、DPS(4)、TYS(3)、HJZ(2),群体的单倍型多样性(Hd)和核苷酸多样性(π)分别为0.732和0.001 39。9个单倍型中,单倍型H1和H5处于进化网络图的中心节点上,并且包含资源数量最多,属于比较原始的单倍型。同时,nSSR和cpDNA的AMOVA分析结果基本一致,居群内的变异百分比分别达到96.69%和80.54%,城步峒茶的遗传变异主要存在于居群内。