叶螨滞育的研究进展

本文概述了近年来国内外对叶螨滞育的研究进展。明确了叶螨的滞育多为兼性滞育。滞育螨态是由种的遗传性所决定。多为卵滞育或受精雌成螨滞育，卵和受精雌成螨均能滞育的种类较少，未见有以幼、若螨滞育的种类。论述了环境因素（光周期、温度、寄主营养）对叶螨滞育的影响和滞育解除的条件。并对叶螨滞育的机制和滞育期的生理变化进行了探讨。     

夏播大豆田截形叶螨发生为害及种群动态的初步研究

通过对太谷地区夏播大豆田截形叶螨的田间为害及发生规律进行观察研究，结果表明：在太谷地区截形叶螨从夏播大豆幼苗期即开始为害，７月下旬达到为害高峰，为害盛期持续１个月之久。同时表明，截形叶螨不同虫态虫口密度的最大叶区不同，其中成虫、卵主要分布在植株的中上部叶片上，幼虫、若虫主要分布在植株的中下部叶片上。     

温度对玉米截形叶螨生长发育的影响

在15℃－35℃恒温条件下，玉米截形叶螨Tetranychus truncatus的发育历期与温度呈负相关；雌、雄螨1代发育起点温度分别在12．60和12．65℃，有效积温各为137．78和121．52日度；25℃－35℃时卵孵化率和幼若螨存活率都较高，并且发育速率较快，该范围是截形叶螨生长发育的最适度。     

4种农药对夏播大豆田截形叶螨防治效果的研究

通过对截形叶螨室内外药效试验表明 ,哒螨酮与灭扫利 1∶1的混合液对截形叶螨活动态螨防效最好 ,1d室内防效可达 98.6 %以上 ,种群数量较小时 ,大田防效可达 90 .2 4 %。其次为 15 %的哒螨酮。当截形叶螨大发生时 ,供试药剂防效均较差。因此对截形叶螨应及早进行防治     

保护地黄瓜截形叶螨种群动态的研究

截形叶螨在保护地黄瓜上的空间格局为聚集分布．分布的基本成分为个体群,聚集强度与叶螨的密度有关,随着密度的上升而下降;截形叶螨在保护地黄瓜上呈指数增长,模型为N1=1．3634e^0.31261(R=0．9174^**)。应用最优分割法将截形叶螨种群动态划分为3个阶段：初建期、发展期和高峰期。在种群初建期,截形叶螨开始迁入,数量较低,以扩散为主,分布不均匀,聚集强度较高;在发展期,截形叶螨种群不断扩散,分布日均匀,聚集强度逐渐下降;在高峰期,截形叶螨种群数量急剧增长到高峰,聚集强度继续下降,此阶段由于黄瓜接近成熟及受害枯萎．截形叶螨因缺少食物而数量急剧下降。     

食螨隐翅虫捕食截形叶螨与柑桔全爪螨的比较

食螨隐翅虫是本地控制叶螨为害的优势种群之一 ,研究其捕食截形叶螨和柑桔全爪螨发现 :食螨隐翅虫捕食2种叶螨存在一定的差异性 ;同时 ,食螨隐翅虫对叶螨的捕食以咬食叶螨和吞食整个螨体相结合。     

叶螨染色体的制备与观察初步研究

以叶螨科中五种叶螨的卵为材料进行叶螨染色体的制备与观察。其方法为四个步骤：（１）低温保存；（２）染色；（３）压片和封片；（４）观测。结果表明：朱砂叶螨，截形叶螨，和土耳其斯坦叶螨的染色体数目均为ｎ＝３笔２ｎ＝６、，但其染色体相对长度存在差异；     

张掖地区玉米害螨的发生与防治对策

甘肃省张掖地区玉米田害螨有截形叶螨（Tetranychus truncatus Ehara)和朱砂叶螨（Tetranychus cinnabarinus Boisdural)，以截形叶螨为优势种。在张掖年发生10－11代，以雌成螨越冬，3月下旬至4月上旬从越冬场所爬出活动，开始在杂草上产卵，7月中旬至8月下旬是为害盛期，高温干旱年份发生严重。综合控制与药剂防治结合是防治叶螨的有效措施。     

玉米截形叶螨实验种群生殖力表

在28℃±0.5℃的条件下,应用叶盘法组建了玉米截形叶螨实验种群生殖力表。结果表明,截形叶螨各螨态发育历期分别为:卵3.56d～3.77d,幼螨2.08d～2.52d,若螨2.15d～3.44d,成螨16.85d～21.00d;完成1代需8.00d～10.52d,寿命24.85d～32.76d。t检验表明,除卵期、幼螨期外,雌螨和雄螨在其它虫态历期间均存在显著(t0.05=2.03,df=36,p<0.05)或极显著(t0.01=2.72,df=36,p<0.01)的差异。单雌总产卵量为89.72粒,日均产卵量5.64粒;雌成螨羽化后平均1.24d开始产卵,产卵率曲线表现为单峰型,日均产卵率在羽化后6d～10d达到高峰,此后迅速下降。截形叶螨在玉米上的存活曲线属于Ⅰ型曲线,死亡多发生于发育后期;净增殖率(R0)为37.5628,周限增长率(λ)为1.2221,内禀增长率(rm)为0.2006,世代平均周期(T)为18.0755d,种群加倍时间(DDP)为3.4554d。     

关于雄性截形叶螨生物学特性的研究

在自动控制温度和光照长度的小室内，采用二次回归通用设计的方法，对雄性截形叶螨生物特性进行了初步研究．结果表明：雄性截形叶螨的个体发育过程与雌螨相同，即经过卵、幼螨、前若螨、后若螨及成螨五个时期．且从一个世代的发育历期来看，温度的作用明显大于光照长度的作用；温度和光照长度之间存在正向互作关系，但并不显著．在３３ ．４ ℃、１１ ．５３ ｈ／ｄ 光照条件下，完成一个世代所需的时间最短，其值为４ ．８９ ｄ     

Structure of the hydrated alpha-Al(2)O(3) (0001) surface

The physical and chemical properties of the hydrated alpha-Al(2)O(3) (0001) surface are important for understanding the reactivity of natural and synthetic aluminum-containing oxides. The structure of this surface was determined in the presence of water vapor at 300 kelvin by crystal truncation rod diffraction at a third-generation synchrotron x-ray source. The fully hydrated surface is oxygen terminated, with a 53% contracted double Al layer directly below. The structure is an intermediate between alpha-Al(2)O(3) and gamma-Al(OH)(3), a fully hydroxylated form of alumina. A semiordered oxygen layer about 2.3 angstroms above the terminal oxygen layer is interpreted as adsorbed water. The clean alpha-Al(2)O(3) (0001) surface, in contrast, is Al terminated and significantly relaxed relative to the bulk structure. These differences explain the different reactivities of the clean and hydroxylated surfaces.     

脱落酸(Abscisic acid, ABA)对映异构体的生物活性比较

 采用新方法精制脱落酸(ABA)异构体试样,改变以往靠光学离析法分离racemic型(SR)-(±)-ABA,提高了(S)-(+)-ABA与(R)-(-)-ABA两镜像体纯度。抑制生长试验和残留量分析结果表明:天然型(S)-(+)-ABA活性,显着高于非天然型(R)-(-)-ABA或(SR)-(±)-ABA活性。抑制莴苣种子发芽50%的活性强度(S)-(+)-ABA约是(R)-(-)-ABA的5倍,(SR)-(±)-ABA介于二者之间。抑制萝卜下胚轴生长试验,最显着有效期2～6天,(6天后差异渐小,8日甚微),生理作用期约为一周,(S)-(+)-ABA活性是(R)-(-)-ABA的3.6倍。差异原因可能是两异构体分子立体结构不同所致。     

山西三点棍腹实蝇和具条实蝇种群动态监测

2006年,于山西的侯马、长治、交城、祁县、太原,在Steiner诱捕器内加T,Cue,Me诱剂诱集各种实蝇,监测山西境内实蝇的发生动态。结果表明,三点棍腹实蝇(Dacus(Callantra)trimacula(wang))和具条实蝇(Bactrocera(Zeugodacus)scutelltat(Hendel))是山西的优势实蝇种群,各诱集点两种实蝇种群动态基本一致,每年的6月底7月初由南到北相继发生,高峰期出现在8月中下旬至9月上中旬,种群消退结束于9月底到10月上旬。两种实蝇一年发生一代,种群羽化整齐。     

Ultrafast mid-infrared response of YBa(2)Cu(3)O(7-delta)

Optical spectra of high-transition-temperature superconductors in the mid-infrared display a gap of in-plane conductivity whose role for superconductivity remains unresolved. Femtosecond measurements of the mid-infrared reflectivity of YBa(2)Cu(3)O(7-delta) after nonequilibrium optical excitation are used to demonstrate the ultrafast fill-in of this gap and reveal two gap constituents: a picosecond recovery of the superconducting condensate in underdoped and optimally doped material and, in underdoped YBa(2)Cu(3)O(7-delta), an additional subpicosecond component related to pseudogap correlations. The temperature-dependent amplitudes of both contributions correlate with the antiferromagnetic 41-millielectronvolt peak in neutron scattering, supporting the coupling between charges and spin excitations.     

The spin excitation spectrum in superconducting YBa(2)Cu(3)O(6.85)

A comprehensive inelastic neutron scattering study of magnetic excitations in the near optimally doped high-temperature superconductor YBa(2)Cu(3)O(6.85) is presented. The spin correlations in the normal state are commensurate with the crystal lattice, and the intensity is peaked around the wave vector characterizing the antiferromagnetic state of the insulating precursor, YBa(2)Cu(3)O(6). Profound modifications of the spin excitation spectrum appear abruptly below the superconducting transition temperature T(c), where a commensurate resonant mode and a set of weaker incommensurate peaks develop. The data are consistent with models that are based on an underlying two-dimensional Fermi surface, predicting a continuous, downward dispersion relation connecting the resonant mode and the incommensurate excitations. The magnetic incommensurability in the YBa(2)Cu(3)O(6+)(x) system is thus not simply related to that of another high-temperature superconductor, La(2-)(x)Sr(x)CuO(4), where incommensurate peaks persist well above T(c). The temperature-dependent incommensurability is difficult to reconcile with interpretations based on charge stripe formation in YBa(2)Cu(3)O(6+x) near optimum doping.     

杨树蛀干性害虫杨大透翅蛾的发生与防治

本文对我国北方杨树蛀干性害虫杨大透翅蛾(Aegerla apiformls clerck)进行了研究。除对形态特征,生活史,生活习性记述外,着重该虫的发生量与营林措施及不同杨树品种的关系,以及一系列的防治试验。在此基础上提出成虫期采用活雌虫性诱;卵期树干涂白;幼虫期使用熏蒸毒签等经济有效的防治手段。同时营造乔灌混交林,选用抗虫性较强的毛白杨等13个品种,可有效地控制该虫的发生量。     

齐口裂腹鱼和重口裂腹鱼消化道形态和组织结构的观察

本文对齐口裂腹鱼和重口裂腹鱼消化道的大体形态及显微结构进行了观察和比较，并探讨了结构与食性的关系。两种鱼消化管分为口腔、咽、食道、肠等四个部分；消化道管壁除口腔、咽外均由粘膜、粘膜下层、肌层和浆膜构成；食道上皮均为复层扁平上皮；肠上皮主要由柱状细胞和杯状细胞组成，其间有嗜酸性颗粒细胞；杯状细胞的数量在前、中肠少，后肠增多；两种鱼在口腔、咽形态组织结构，肠长度和盘曲程度方面差异较大，与其食性密切相关。     

Signature of superfluid density in the single-particle excitation spectrum of Bi(2)Sr(2)CaCu(2)O(8+delta)

We report that the doping and temperature dependence of photoemission spectra near the Brillouin zone boundary of Bi(2)Sr(2)CaCu(2)O(8+delta)exhibit unexpected sensitivity to the superfluid density. In the superconducting state, the photoemission peak intensity as a function of doping scales with the superfluid density and the condensation energy. As a function of temperature, the peak intensity shows an abrupt behavior near the superconducting phase transition temperature where phase coherence sets in, rather than near the temperature where the gap opens. This anomalous manifestation of collective effects in single-particle spectroscopy raises important questions concerning the mechanism of high-temperature superconductivity.