中国栅蛛属2新种记述(蜘蛛目:栅蛛科)

本文记了分别采自云南高黎贡山的栅蛛科栅蛛属Hahnia 2新种:垭口栅蛛,新种S.yakouensis sp.nov.和肾形栅蛛,新种S.reniformis sp.nov..垭口栅蛛后眼列前曲,交媾腔大,扁圆形,交媾孔1个,位于交媾腔下缘,交媾管粗,呈"人"字形下行分成2支再向两侧扭曲.纳精囊有一肓管斜向上伸出,鉴于上述特征而与Hahnia mridulae Tikader,1970不同.肾形栅蛛交媾孔2个,位于生殖厣腹面中央,纳精囊1对,大,肾形,插入器始于生殖球左下方,鉴于上述特征而与Hahnia xinjiangensis Wang et Liang,1989不同. Abstract： The present paper deals with two new species of the genus Hahnia collected from the Gaoligong Mountains Region of Yunnan Province, China: Hahnia yakouensis sp. nov., Hahnia reniformis sp. nov..     

注重发挥博士后科研生力军作用

中国医科大学博士后科研流动站始建1995年。目前学校设有基础医学、临床医学和生物学3个博士后科研流动站。但由于每年国家财力有限,资助名额很少,在有限条件下建立、健全博士后制度,加强对博士后人员的培养,调动博士后人员的积极性是一项重要的研究课题。     

遗传物质的发现者之一——麦卡锡

1944年,3位科学家艾弗里、麦卡锡和麦克劳德在DNA遗传本质方面的发现是20世纪最重要的发现之一,这个发现打开了生物学革命的大门,从而改变了人类对自然界的看法,这项研究还为1953年沃森和克里克DNA双螺旋结构的发现奠定了坚实的基础,但不幸的是3位科学家都未曾荣获诺贝尔奖.通过介绍麦克林·麦卡锡的科学研究,从而对这项发现的基本状况有一个基本的了解.     

生命之树与进化模式:导言

One and half centuries ago, Charles Darwin (1859) presented overwhelming evidence and argued that all life on the earth shared common descent, and "from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved". Ernst Haeckel (1886) and several of his contemporaries attempted to trace the pattern of descent among all extant and extinct forms in what Darwin referred to as "the great Tree of Life". Ever since then, systematists and evolutionary biologists have been exploring morphological, cytogenetic, chemical, developmental and molecular characters, and actively developing theories and methods to infer phylogenetic relationships among organisms from these characters. This endeavor has been especially stimulated by the rise of molecular biology and the emergence of computer science over the past 50 years. At the beginning of the 21st century, we are presented with an unprecedented opportunity to reconstruct the entire Tree of Life, and further, to study evolutionary processes and mechanisms in the context of a robust phylogenetic framework.     

我国微生态学的奠基人——魏曦

魏曦,字东升,1903年12月25日出生于湖南岳阳一个小职员家庭,父亲任职于邮政局.1914～1921年他在家乡湖滨中学读书,毕业后考入长沙湘雅医学院,学习两年后曾参加北伐军,任第四集团军警卫团三等军医.后退出军队,在长沙广雅中学任教.1928年入设立在上海的中央大学医学院(1932年独立为上海医学院)学习,1933年毕业,获博士学位.     

高黎贡山北段东西坡种子植物区系的比较研究

高黎贡山北段的东西坡由于在降雨量和热量分配等方面存在着显著的差异,致使东西坡在植物的种类、组成及区系特征等方面表现出明显的差异.东坡记载野生种子植物152科,580属,1475种及192变种(亚种),西坡记载野生种子植物162科,659属,1804种及186变种(亚种).东西坡种子植物科、属、种的对比分析表明:1)东西坡现代种子植物区系具有相同的历史渊源,但其区系联系减弱了,东西坡区系相似性程度,依科、属、种的顺序依次递减;2)西坡现代种子植物区系比东坡具有更为深刻的热带起源烙印.就科、属、种三个水平来说,东坡的热带成分低于西坡,温带成分高于西坡.许多典型的泛热带大科在西坡比东坡有着更为丰富的种类,其中有些泛热带科分子在东坡缺乏分布,而在西坡找到了合适的驻留之地;3)西坡现代种子植物区系与东喜马拉雅植物区系的联系比东坡紧密,而东坡与高黎贡山以东的区系联系比西坡密切,由于高黎贡山山脉的阻隔,近代植物物种的东西坡交流发生了障碍;4)西坡生态地理环境比东坡更有利于物种的生存、繁衍和分化,它既是古老成分的避难所,又是孕育新生成分的摇篮.     

用叶绿体ndhF和核核糖体ITS序列推断李属(蔷薇科)的系统发育

Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to reconstruct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets are congruent in that the genera Prunus s.l. and Maddenia form a monophyletic group, with Maddenia nested within Prunus. However, the ndhF data set is incongruent with the ITS data supporting two major groups within Prunus one consisting of subgenera Laurocerasus (including Pygeum) and Padus as well as the genus Maddenia and another of subgenera Amygdalus, Cerasus, and Prunus. The ITS data, on the other hand, support a clade composed of subgenera Amygdalus and Prunus and Prunus sect. Microcerasus in addition to a paraphyletic grade of subgenera Laurocerasus and Padus (and the genus Maddenia) taxa. In general, the subgeneric classifications of Prunus s.l. are not supported. The ITS and ndhF phylogenies differ mainly in interspecific relationships and the relative position of the Padus/Laurocerasus group. Both ITS and ndhF data sets suggest that the formerly recognized genus Pygeum is polyphyletic and that the distinction of the subgenera Padus and Laurocerasus is not supported. The biogeographic interactions of the temperate and tropical members in the Padus/Laurocera- sus/Maddenia alliance including Pygeum are shown to be highly dynamic and complex.     

鸡的瞬膜

瞬膜(nictitating membrane),又称第三眼睑,是一种保护眼球、防止灰尘的结构.鸟类的瞬膜位于眼眶的前眼角,为半透明的膜,其内缘具有一种羽毛上皮,借以刷洗角膜上的灰尘.在飞行时能遮覆眼球,以避免干燥气流和灰尘对眼球的伤害.由于瞬膜在鸟类睁眼的一瞬间迅速缩回前眼角,很难拍摄到.最近费了好大的周折,终于拍到了理想的鸡瞬膜照片,现予以发表供生物学界的同行共享(友情提示:如引用请注明原作者).     

途经甘肃的3种水鸟新纪录

2007年10月13日至11月5日进行敦煌市湿地鸟类调查时,分别在南湖湿地与候鸟自然保护区及党河水库使用Leica apo77高倍望远镜观察到3种水鸟,在以往的文献资料中未见其分布于甘肃的报道,应为甘肃鸟类新纪录。笔者用500mm镜头分别拍下3种水鸟的照片。1.赤颈(Podiceps grisegena)2007年10月13日13:30时,在南湖湿地与候鸟自然保护区的阳关水库(渥洼池)记录到2只赤颈。当时水面上同时有凤头(P.cristatus)、黑颈(P.nigricollis)以及大量鸭类、潜鸭类游禽活动,赤颈体形较凤头小,而又明显比黑颈大。其中一只赤颈的…     

Hot-water immersion quarantine treatment against Mediterranean fruit fly and Oriental fruit fly (Diptera: Tephritidae) eggs and larvae in litchi and longan fruit exported from Hawaii

Immersion of litchi fruit in 49 degrees C water for 20 min followed by hydrocooling in ambient (24 +/- 4 degrees C) temperature water for 20 min was tested as a quarantine treatment against potential infestations of Mediterranean fruit fly, Ceratitis capitata (Wiedemann); and oriental fruit fly, Bactrocera dorsalis Hendel, eggs or larvae in Hawaiian litchi, Litchi chinensis Sonnerat. The 49 degrees C hot-water immersion of litchi provided probit 9 (99.9968% mortality with >95% confidence) quarantine security against eggs and first instars. There were no survivors from 15,000 each feeding and nonfeeding Mediterranean fruit fly or oriental fruit fly third instars immersed in a computer-controlled water bath that simulated the litchi seed-surface temperature profile during the 49 degrees C hot-water immersion treatment. Litchi served as the model for longan, Dimocarpus longan Lour., a closely related fruit that is smaller and also has commercial potential for Hawaii. Modified fruit infestation and holding techniques used to obtain adequate estimated treated populations from poor host fruit, such as litchi and longan, are described. Data from these experiments were used to obtain approval of a hot-water immersion quarantine treatment against fruit flies for litchi and longan exported from Hawaii to the U.S. mainland.     

荔枝的活性功能及主要功能物质研究进展

荔枝是药食兼用水果,传统中医和民间一直用其滋补身体,是广东省最主要的经济作物水果,对其农业和经济发展具有重要作用。但长期以来其物质基础和作用机制不清楚,且国内荔枝发展绝大部分还限于粗放的农产品加工,对其附加价值认识不充分,严重限制了荔枝产品的开发和产业的升级。近年来国内外对荔枝的活性功能及主要功能物质研究较为活跃。本文从荔枝果皮、果核、果肉、花方面综述了荔枝的抗氧化、抗辐射和保护肝脏等主要活性,并对其酚类等主要活性物质的提取分离方法及其组成、化学结构和含量等进行了全面梳理归纳,旨在为荔枝功能食品及副产品的精深加工提供依据。     

荔枝与龙眼种质资源研究进展

荔枝和龙眼是中国著名的南亚热带果树。本文分别就荔枝、龙眼种质资源在起源与分布、分类与鉴定等方面取得的研究进展进行了综述。荔枝和龙眼的分类研究大体经历了3个阶段:根据形态特征进行分类、应用同工酶分析和DNA分子标记进行分类。形态特征常常受到环境条件的影响,而同工酶分析可以检测到的多态性位点十分有限。应用分子标记研究荔枝、龙眼种质资源的遗传多样性克服了前述2种研究方法的不足。目前,荔枝和龙眼的品种选育仍然以实生选种和芽变选种为主。为了实现对荔枝、龙眼果实品质和农艺性状的改良,建议在分子水平上进一步深入地探讨荔枝、龙眼种质资源的遗传多样性;同时通过应用分子标记辅助选择技术提高荔枝和龙眼杂交育种的效率。     

Fingerprinting and analysis of genetic diversity of litchi (Litchi chinensis Sonn.) accessions from different germplasm collections using microsatellite markers

Litchi (Litchi chinensis Sonn.) is a fruit crop with a clear niche for expansion in countries with subtropical climates. One of the main limitations for breeding purposes and optimum germplasm management in this species is the confusion in cultivar denomination among different producing countries and germplasm collections worldwide. Litchi cultivar identification is still mainly based on morphological characters, and homonymies and synonymies are very frequent. To address this gap, a molecular study was conducted to characterize litchi accessions from two of the main litchi-producing regions for the export market, Mauritius and Réunion, and to compare them to those obtained from litchi cultivars from different origins conserved in a germplasm collection in Spain. Eleven simple sequence repeat (SSR) loci were used to characterize molecular polymorphisms among 88 litchi accessions conserved in Mauritius, Réunion, and Spain. A total of 67 amplification fragments were detected with those 11 SSRs, with an average of 6.1 bands/SSR. Three primer pairs seemed to amplify more than one locus. The mean expected and observed heterozygosities over the eight single locus SSRs averaged 0.53 and 0.61, respectively. The total value for the probability of identity was 9.78?×?10^?4. Molecular characterization revealed the existence of 42 different genetic profiles. Several synonymies and homonymies in litchi cultivar nomenclature both within and across geographical regions were found. This comparative study provides the basis for the standardization of litchi cultivar nomenclature over the studied regions and in other litchi-producing countries.     

霜疫霉菌侵染对荔枝氧化作用的影响

淮枝、桂味和糯米糍 3种荔枝经接种霜疫霉菌后 ,果皮超氧化物歧化酶 (SOD)和过氧化氢酶 (CAT)活性下降 ;而过氧化氢 (H2 O2 )含量升高 ,超氧阴离子自由基 (O2 .)产生速率增加 ,丙二醛 (MDA)积累增多 ,与果实感病指数增加相一致 ,表明霜疫霉菌侵染加速荔枝氧化作用的进程。实验还表明不同荔枝品种对霜疫霉菌抵抗力与其自由基清除能力有关     

荔枝蒂蛀虫绿色防控研究进展

中国是荔枝(Litchi chinensis)的原产地,种植面积和产量规模均居世界第一位,以“岭南果王”著称的中国荔枝在国际鲜果市场享有极高的声誉。荔枝蒂蛀虫(Conopomorphasinensis)在我国广泛分布于热带南亚热带地区,是荔枝的主要害虫,其幼虫蛀食荔枝果核、果蒂,会影响果实生长发育及商品果率,造成严重的经济损失。荔枝蒂蛀虫的行为隐蔽,世代重叠,难以控制。目前生产上对该虫的控制主要依靠化学防治,但长期使用化学农药容易产生污染环境、药物残留、食品安全以及虫抗药性的问题。本文结合国内外研究进展,着重从荔枝蒂蛀虫生活习性及危害发生规律、预测预报、物理防治、生物防治及生物源农药应用等方面进行综述,并对荔枝蒂蛀虫绿色防控研究方向及以农业防治为基础的综合防治方法进行展望。     

大核和焦核"桂味"荔枝果实发育及其发育期间果皮中内源激素含量的变化比较

同一株大核和焦核"桂味"荔枝的果实生长型均呈"单S型",其果实大小差异主要由种子大小不同引起.果实发育期间,两者果皮中内源激素变化的规律大体上一致,大核果皮中GA3、IAA含量和(IAA ZRs GA3)/ABA比值均高于焦核果皮,但ZRs含量和ZRs/ABA比值则比其低,ABA含量的差异无规律可循.     

Intergeneric Hybridisation between Litchi (Litchi chinensis Sonn.) and Longan (Dimocarpus longan Lour.)

The breeding barriers between commercial litchi (Litchi chinensisSonn.) and longan (Dimocarpus longan Lour.) cultivars were investigatedby conducting reciprocal pollinations. This work has shown thatit is possible to generate intergeneric hybrids using litchias the female parent. Investigation of comparative in vivo pollentube growth demonstrated that there is discrimination againstcross- compared to self-pollen at all sites in the pistil. Pollentubes were frequently observed in the ovary after cross-pollinationin litchi but rarely in longan. Fruit production was reducedafter crossing in both longan and litchi. Isozyme analysis usingphosphoglucose isomerase revealed that hybrid progeny only developedwhen litchi was the maternal parent. Morphologically the hybridplants were similar to the maternal parent but leaves were smaller.Three types of seeds developed in litchi following pollinationwith longan pollen. These were (1) normal seeds with a developedtesta and embryo, (2) seeds with aborted embryos but normaltesta development, and (3) seedless fruit where the ovule remainedthe same size as at anthesis without further development ofembryo or testa. The potential germplasm available to improvethese crops within the Sapindaceae is discussed.Copyright 1994,1999 Academic Press Litchi, Litchi Longan, Dimocarpus, hybridisation, isozyme     

蔗糖基聚合物对妃子笑荔枝座果率及其叶片中几种抗氧化酶活性的影响

用2%浓度的蔗糖基聚合物处理妃子笑荔枝,研究其对荔枝叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性的影响。结果表明,在小果期喷施蔗糖基聚合物可提高妃子笑荔枝座果率,提高SOD、CAT活性,降低POD活性,在植株的抗逆、抗病及防止果实落果方面效果显著。     

荔枝若干重要果实品质性状的QTL分析

以‘马贵荔＇ב焦核三月红＇76株F_1代群体为试材,检测了酒石酸、苹果酸、蔗糖含量和单果重4个果实性状分离的情况。结果表明,4个性状表现为连续分布,具有数量性状的典型特征,与4个果实性状连锁的QTL位点23个,其中控制酒石酸的QTL为2个,控制苹果酸的QTL为4个,控制蔗糖的QTL为12个和控制单果重的QTL为5个。各QTL的LOD值在3.15～5.61之间,可解释13.85%～88.3%的表型变异。