神农架地区珍衡植物沿河岸带的分布格局

Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m×100m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200–1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection. Foundation item: This project was supported by National Natural Science Foundation of China (NSFC39970123), and Changbai Mountain Open Research Station, Chinese Acadamy of Science. Biography: JIANG Ming-xi (1965-), male, associate professor in Wuhan Institute of Botany, Chinese Academy of Sciences, Wuhan 430074, P. R. China Responsible editor: Chai Ruihai     

筋骨草内昆虫蜕皮激素类似物对杨干象的杀虫作用

从不同地点、不同时间采集的多花筋骨草植株不同部位中提取出昆虫蜕皮激素类似物,通过向幼虫人工饲料中添加昆虫蜕皮激素类似物的方法,研究了筋骨草中植物源蜕皮激素对杨干象2龄幼虫的杀虫作用。实验结果表明:(1)在人工饲料中加入1-3 ml的筋骨草提取物,在24天内可以杀死 58%~100%的幼虫;(2)从开花前的筋骨草中提取出的物质的杀虫效果明显优于从花期和开花后的植物中提取出的物质的杀虫作用, 其1 mL、2 mL和3 mL剂量全株提取物的杀虫效果分别达到65.22%、85.07%和98.11%(幼虫校正死亡率);(3)植株的根部提取的昆虫蜕皮激素类似物的杀虫效果要比茎部或叶部提取的好,1 mL、2 mL、3 mL剂量提取物的杀虫效果分别达到100%、98.20%和98.32%;(4)筋骨草提取物的杀虫速度较慢,处理杨干象2龄幼虫16天后杀虫率才超过50%;(5)幼虫取食加有筋骨草提取物的饲料时间长短直接影响幼虫死亡率,16天的取食,幼虫死亡率达到80%以上。筋骨草采集地点和填加植物源蜕皮激素的方式对杀虫效果的影响较小。图3表3参21。     

中国吉林森林生态网络现状与展望

本文概要介绍了吉林省生态环境概况、林业建设成就与问题,论述了本省森林生态网络建设面临的任务及亟待解决的八个方面的问题,并对生物技术、信息技术、新材料技术及无公害森林保健技术在森林生态网络建设的应用前景进行了展望。参9。     

红松高生长模型的研究(英文)

高生长模型是定量研究树木生长过程的有效途径,本文应用双曲线方程、Logistic方程、三个参数的Richards方程及四个参数的Richards方程对红松的高生长进行了研究。结果表明四个参数的Richards方程在模拟红松高生长时最为合适,且当其参数取不同的数值时,该方程可转化为其它理论方程。在使用四个参数的Richards方程时,可根据立地条件事先给定树高最大值,这样可使模型更符合实际情况。此外,文中还对一种以固定年龄时实际树高为参数值的模型进行了讨论,该模型对于计算给定树木的高生长将更为有效。     

杉木幼林年生长节律划分和相关气候因素分析

杉木幼林年生长规律及气候因素对生长的影响,是合理制订杉木产区区划,改善杉木造林规划设计布局,正确实施经营管理措施的基础。 本项研究,将全国杉木西部试区的四川高县作为试验点,从1985～1988年,连续4年在5～8年生不同密度林分中,作了胸高直径及树高生长的旬期定期观测。经对这些实验数据作均值处理,聚类分析,关联分析和多元回归分析结果表明:对生长在中国杉木中带西部产区,处于中亚热带湿润气候区环境条件下的杉木幼林年生长规律的论证及对影响生长的主要气候因子的分析判断和预测,具有可靠性和区域代表性。     

伞房属4个树种/亚种在广东乐昌的早期生长表现

分析引自澳大利亚东部的桃金娘科（Myrtaceae）伞房属(Corymbia) 4个树种/亚种在广东省乐昌试验点的早期生长表现,结果表明：10 a生时,4个树种/亚种生长量最大的是大叶斑皮桉（Corymbia henryi）,其次是斑皮柠檬桉（Corymbia citriodora ssp. variegata）、柠檬桉（Corymbia citriodora ssp. citriodora）和斑皮桉（Corymbia maculata）,平均单株材积分别为0067 4、0059 0、0054 1和0034 1 m3;与8 a生时比较,4个树种/亚种在10 a生时仍保持较快的增长速度,材积增长均在67%以上,其中斑皮桉的材积增长率高达1450%。方差分析结果表明：在试验组Ⅰ,柠檬桉和大叶斑皮桉3个生长性状在家系间差异极显著（P＜001）,种源间胸径差异达极显著水平（P＜001）,树高差异达显著水平（P＜005）,单株材积差异不显著;在试验组Ⅱ,斑皮柠檬桉和斑皮桉3个生长性状在种源、家系间差异极显著（P＜001）。以单株材积高于对照为选择目标,选出大叶斑皮桉2个种源2个家系,斑皮柠檬桉5个种源11个家系,共计7个种源13个家系,分别占参试种源和家系总数的389%和140%。     

鸭坦布苏病毒E基因的分子特性分析

为给鸭坦布苏病毒（duck tembusu virus,DTMUV）囊膜糖蛋白选择良好的抗原域和宿主表达系统提供参考依据,本研究通过选取DTMUV QD株基因文库中的一个重组质粒并测序,结合NCBI的ORF Finder和BLAST工具发现一个全长为1488 bp完整开放阅读框架（Open Reading Frame,ORF）片段。将该ORF编码蛋白通过NCBI的BLASTP分析和DNAstar进化树分析,确定该蛋白与类黄病毒E基因编码的蛋白具有较高的相似性。随后应用生物信息学分析工具Conserved Domains确定保守结构域、运用SignalP4.1预测信号肽、TMHMM 2.0预测跨膜区。应用在线程序NetNGlyc1.0预测糖基化位点,NetPhos2.0预测磷酸化位点、ProtScale进行疏水性分析。最后运用在线EMBOSS和自动蛋白同源建模数据库进行3D结构预测以及密码子偏爱性分析。结果表明,E蛋白与其它黄病毒衣壳蛋白具有相似的功能,没有信号肽切割位点,在451-468和475-492aa区域含有跨膜区,为相对低表达基因,含有较多种类的稀有密码子,与人密码子使用频率较为接近。这为进一步研究DTMUV E基因的体外表达和宿主选择提供了分子生物学依据。     

Gastric inflammatory pseudotumour secondary to <Emphasis Type="Italic">Actinomyces hordeovulneris</Emphasis> infection in a cat

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.

     

Use of serology and real time PCR to control an outbreak of bovine brucellosis at a dairy cattle farm in the Nile Delta region,Egypt

Background

Bovine brucellosis remains one of the most prevalent zoonotic infections affecting dairy cattle in developing countries where the applied control programs often fail. We analyzed the epidemiologic pattern of bovine brucellosis in a dairy cattle herd that showed several cases of abortions after regular vaccination with RB51 (B. abortus vaccine). In 2013 thirty dairy cows, from a Holstein-Friesian dairy herd with a population of 600 cattle, aborted five months post vaccination by a regular RB51 vaccine. Blood samples were drawn from milking cows and growing heifers, as well as heifers and cows pregnant up to 6 months. These samples were collected in June 2013 (n?=?257) and May 2014 (n?=?263) and were tested by real time (rt)-PCR as well as serological tests, in particular Rose Bengal Test (RBT), Enzyme-Linked Immunosorbent Assays (ELISA) and Fluorescence Polarization Assay. Tissue specimens were also collected from an aborted fetus and cultured. Isolates were subjected to bacteriological typing tests at the genus and species levels.

Results

Five months post vaccination with RB51 vaccine, Brucella (B.) DNA was detected in blood samples of cows by rt-PCR. The serological tests also revealed the spread of Brucella field strains within the herd in 2013. Four Brucella isolates were recovered from specimens collected from the aborted fetus. These isolates were typed as follows: one B. abortus RB51 vaccine strain and three isolates of B. abortus field strain. The seropositive cows with positive rt-PCR might indicate an infection by the Brucella field strain; while the positive rt-PCR results from seronegative animals may either be due to circulating RB51 vaccine DNA in vaccinated animals or to circulating field strain in infected animals before seroconversion.

Conclusion

The results herein suggest that PCR can be a good supplementary tool in an outbreak situation, if an assay is available that can differentiate vaccine and field strains with a high analytical sensitivity. We recommend using RBT and ELISA in parallel in outbreak situations, to identify as many infected animals as possible during the initial screenings. This test procedure should be repeated for at least three successive negative tests, with one month interval.