扑虱灵大田防治桑白蚧的效果

在桃树桑白蚧一龄若蚧盛发期,用25％扑虱灵可湿性粉剂1000～1500倍稀释液、防治1次,就可有效地控制其为害,是抗治该蚧的理想药剂。对一龄若蚧防治效果为92．2％～96．3％,持效期长达3周以上,但毒杀速度较慢。     

不同杀菌剂对柑桔红蜘蛛生物学特性的影响

本研究报道柑桔园5种常用杀菌剂。在田间使用浓度下。对柑桔红蜘蛛Panonychus cltrl生物学特性的影响．在25±1℃．相对湿度75±5％,光照周期14L：10D的条件下,70％甲基托布津可湿性粉剂1500倍液、80％代森锌可湿性粉剂800倍液、50％多苗灵可湿性粉剂800倍液．20％叶青双可湿性粉剂800倍液和0．5％等量式渡尔多液。对柑桔红蜘蛛各螨态历期、雌雄成螨寿命和雌成螨产卵量没有影响．仅70％甲基托布津1500倍液和50％多菌灵800倍液会降低柑桔红蜘蛛卵的孵化率,比对照卵孵化率91.0％分别减少了27．7％和24．3％．     

黄檀丑舟蛾生物学特性及防治的研究

黄檀丑舟蛾是南岭黄檀的重要食叶害虫,该虫在福建南平一年发生6代,以蛹在疏松土壤中越冬,翌年5月初成虫开始羽化。雌虫产卵于嫩叶上,成块。每雌产卵82-306粒。幼虫5龄,各代幼虫的危害盛期;第一代5月下旬至6旬上旬。第二代6月下旬,第三代7月下旬,第四代8月中旬,第五代9月下旬,第六代11月上旬至中旬。试验表明,20%杀灭菊酯4000倍液或80%敌敌畏2000倍液对幼虫均有良好的毒杀效果。     

卫矛矢尖蚧的研究

南京地区卫矛矢尖蚧unaspis euonymi Comstock一年发生3代．第一至三代若虫孵化盛期分别为5月中旬、6月下旬和8月中旬．各代雌成虫始见期分别为5月下旬,6月下旬和8月下旬．11月下旬开始以受精雌成虫在寄主上越冬．主要天敌有红点唇瓢虫Chilocorus kuwanae Silvestri、日本方头甲Cybocephalus nipponicus Enduody-Younga,黄蚜小蜂Aphytis sp．等．药剂防治用机油乳剂。冬季1：30-50倍液(防治越冬代雌成虫),夏季1：50-100倍液;40％氧化乐果1：1000倍液、25％亚胺硫磷乳剂1：800倍液等喷洒1至3代盛孵若虫,杀虫效果均可达95％以上．     

樟脊网蝽生物学特性观察

樟脊网蝽是香樟的重要害虫,在上海1年发生4代。4月下旬越冬卵始孵,9月下旬开始出现越冬卵。成虫末见期在11月中旬。经室内饲养,樟脊网蝽第三代各龄若虫历期为：一龄61．45±7．8h,二龄48．00±7．6h,三龄43．43±7．6h,四龄51．00±8．0h,五龄70．50±7．5h,整个若虫期历期为281．92±14．8h。第三代野外雌雄比为1：4．07。第三代每雌产2～96粒。日最高产卵量为34粒／头,孤雌可产卵。10％灭百可2000倍稀释液和50％杀螟松2000倍稀释液喷雾防治效果可达93％以上。     

前齿肖蛸的生活史

前齿肖蛸(Tetragnatha praedonia)在湖北省武汉地区一年可发生五代,以低龄幼蛛在杂草丛中越冬。雌蛛一生最多可产5个卵袋,单雌平均产卵量第一代为155.43粒,第二代260.20粒,第三代213.01粒,第四代62.50粒。卵的孵化率各代均在88％以上。各代幼蛛期、产卵前期、全代历期以及成蛛寿命均不相同。能捕食蚊子以及棉田和稻田的多种害虫。     

柿绒粉蚧的发生规律及防治

柿绒粉蚧(柿绵蚧)Eriococcus kaki Kuwana在广西灌阳县1年发生6代,以若虫和成虫在树干裂皮缝、缝隙,1、2年生枝条轮痕、芽基、芽鳞片及干柿蒂上越冬,次年柿树萌芽期开始活动。第1代～第6代低龄若虫高峰期分别为3月下旬～4月上旬初、5月下旬末～6月上旬初、6月下旬末～7月上旬初、8月上旬～中旬初、9月上旬初～中旬初及10月中旬初～11月上旬初。卵期7～18d,若虫期22～136d,成虫期6～140d。柿芽萌动前用99.1%机油乳剂180倍液(敌死虫)或20%松脂酸钠(融杀蚧螨)150倍液清园喷杀,防治效果分别达88%、79.8%。第1代低龄若虫高峰期用40%毒死蜱乳油1000倍液加25%噻嗪酮(扑虱灵)可湿性粉剂1500倍液喷雾,防治效果99.6%,80%敌敌畏乳油800倍液加10%吡虫啉可湿性粉剂2000倍液防治效果达99.1%,3%啶虫脒可湿性粉剂(3%金世纪)2500倍液防治效果99.5%。     

黑胸大蠊浓核症病毒对雌成虫生殖的亚致死影响

用黑胸大蠊浓核症病毒(Periplaneta fuliginosa densonucleosis virus,PfDNV)三种浓度处理黑胸大蠊8-9龄雌性若虫,对雌成虫生殖有亚致死影响。试验结果表明,雌成虫寿命分别平均减少121d、145d和179d;产卵期分别平均缩短62d、56d和121d;每雌成虫产卵鞘数分别平均减少16个(占57％)、20个(占72％)和25个(占88％),每雌成虫产卵数分别平均减少354粒(占55％)、453粒(占71％)和558粒(占86％);生殖力分别平均下降177倍(占55％)、226倍(占71％)和279倍(占88％)。卵鞘活力分别下降28％、28％和20％。雌成虫在产卵盛期的前4个月持续受到DNV的影响,每雌每月平均产卵数分别减少30粒(占40％)、69粒(占48％)、63粒(占47％)和55粒(占50％),生殖力分别下降15倍、34倍、31倍和28倍。     

宽索鳃金龟的研究

宽索鳃金龟是为言猕猴挑的重要食叶害虫．该虫在福建建宁县一年发生一代,以成虫在土中越冬,翌年4月上旬开始出土为害,4月下旬至5月下旬为害盛期,成虫可整夜取食猕猴桃叶片和花器,成虫出土及人土的时间较为整齐．5月上旬雌虫开始在土中产卵,5月下旬开始孵化．幼虫3龄,在土中1-20cm处活动,以8-10cm处占绝大多数,幼虫取食土壤中腐植质和根皮,截根．9月上旬开始化蛹,10月中旬成虫开始羽化。但当年不出土,逗留在土中。并越冬．采用50％辛硫磷1000—2000倍液防治幼虫：80％敌敌畏乳油1000倍．帅％乐果800-1000倍、25％溴氰菊酯5000倍等药液毒杀成虫均有良好效果,亦可人工捕杀和灯光诱杀成虫．     

烟蚜茧蜂生物学及其应用研究

本文系1975—78年在云南玉溪烟区进行的研究结果。烟蚜茧蜂在玉溪终年可以找到寄主产卵寄生,没有越冬滞育现象。发育周期长短与温度有明显关系,25—27℃,一代厉期为9—13天,其中卵期1—2天,幼虫期4—5天,预蛹期1—2天,蛹期3—4天。成虫饲喂糖液,寿命7,8天,最长11天。冬季温低(15℃),寿命较长,平均13.6天,最长40天。雌蜂羽化后可立即交配产卵寄生,产卵1,2天后进入高峰期,产卵高峰期一般3—4天。产卵期较长,在整个成虫期均可产卵寄生。每雌蜂在供给过量寄主时(每日50头成蚜),一生平均产卵量为189.4粒,日平均为24.7粒。寄生蚜虫数为127.6头,每蜂平均在每头寄主蚜虫体内产卵1.5粒。 利用简易薄膜温室饲养蚜虫繁蜂,简便易行。田间散放防治示范试验结果表明,在烤烟生长期,连续释放烟蚜茧蜂可有效地控制烟蚜的发生在防治水平以下。其效果比喷施45％乐果乳剂1000倍液优越。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.