异色瓢虫法国种群对豆蚜的捕食效应

异色瓢虫Harmonia axyridis(Pallas)的法国种群具有飞行能力较低的特点,在生物防治方面可能更具利用价值。为了使其更好的在田间应用,本文进行了异色瓢虫的法国种群各龄幼虫及雌、雄成虫对豆蚜的捕食功能比较研究。结果表明:各龄幼虫及雌、雄成虫对豆蚜捕食功能反应符合Holling II模型,检验各圆盘方程理论值和实测值拟合较好。同一虫态在不同空间水平对蚜虫的捕食能力有显著差异,在广口瓶处理中(较大空间),1～4龄幼虫及雌、雄成虫的最大理论捕食量分别为4.51、83.33、111.12、166.67、190及200头;不同虫期及成虫的瞬间攻击率a为3龄>4龄>雄虫>雌虫>2龄>1龄,且1龄的处理时间Th最长(0.2225);在培养皿处理中(较小空间),1～4龄幼虫及雌、雄成虫的最大理论捕食量分别为6.17、19.23、45.45、100、142.86、111.11头,不同虫期的瞬间攻击率a为2龄>3龄>雄虫>4龄>1龄>雌虫,且4龄的处理时间Th最长(0.1624)。     

椰心叶甲的耐寒力测定

测定椰心叶甲Brontispalongissima(Gestro)的过冷却点和结冰点。各虫态中过冷却点值以卵和蛹最低,分别为-9.8℃和-9.0℃,成虫较高,雌、雄成虫分别为-5.9℃和-5.5℃;幼虫的过冷却点最高,平均为-4.5℃。结冰点由高到低依次为2龄幼虫、5龄幼虫、4龄幼虫、1龄幼虫、3龄幼虫、雄成虫、雌成虫、蛹和卵,分别为-0.3,-0.8,-1.1,-1.3,-1.3,-2.4,-2.7,-5.4和-5.5℃。综合分析认为,蛹、卵的耐寒能力最强。根据广东地区常年平均气温分析了在自然条件下该虫各虫态越冬情况,但由于生物学特性的限制,越冬虫态主要是成虫、蛹。     

亚致死浓度氯虫苯甲酰胺可降低亚洲玉米螟的种群增长

为了探讨氯虫苯甲酰胺对亚洲玉米螟Ostrinia furnacalis (Guenée)的抗性风险评估, 为科学使用氯虫苯甲酰胺防治亚洲玉米螟提供理论基础, 本研究在实验室条件下采用饲料混毒法测定了新型杀虫剂氯虫苯甲酰胺对亚洲玉米螟的毒力, 利用生命表技术研究了氯虫苯甲酰胺对亚洲玉米螟 3龄幼虫的亚致死效应。结果表明： 氯虫苯甲酰胺对亚洲玉米螟3龄幼虫的LC₁₀, LC₄₀ 和LC₅₀分别为0.038, 0.098 和0.123 mg a. i. /L。以氯虫苯甲酰胺LC₁₀和LC₄₀剂量分别处理亚州玉米螟3龄幼虫后, 幼虫和蛹的发育历期明显延长, 成虫寿命缩短, 产卵量也显著降低, 但对蛹重（雌： P=0.337, 雄： P=0.121）、卵孵化率（P=0.087）和性比（P=0.379）无显著影响。处理种群的净增值率（R₀）、内禀增长率（r_m）和周限增长率（λ）显著低于对照种群（P<0.0001）。结果提示, 氯虫苯甲酰胺的亚致死浓度可降低亚洲玉米螟的种群增长。     

寄主植物对亚洲玉米螟生长发育及雄蛾保护酶活性的影响

【目的】为了明确不同寄主植物对亚洲玉米螟Ostrinia furnacalis (Guenée)生长发育、繁殖及雄蛾保护酶活性的影响。【方法】在温度为(25±5)℃、湿度为75%±5%、光照周期为L∶D=16∶8的恒定条件下,研究了7科12种寄主植物对亚洲玉米螟发育历期、蛹期、成虫期、羽化率、雌蛾繁殖力及雄蛾体内超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活力的影响。【结果】亚洲玉米螟能够在12种寄主植物上完成生长发育。取食苍耳的幼虫历期较短(17.4 d),蛹期较短(5.9 d);成虫寿命较长(9.0 d),蛹重较大(50.7 mg);取食油菜的幼虫单雌产卵量较大(210粒/雌),取食油菜和油麦菜的幼虫成活率和蛹羽化率较高,均在80.0%以上。幼虫取食不同植物后,雄蛾体内保护酶的活性差异显著,幼虫取食酸模叶蓼后,雄蛾体内SOD活性较高,幼虫取食苍耳后,雄蛾体内POD和CAT活性较高。【结论】不同寄主植物对亚洲玉米螟生长发育、繁殖及雄蛾保护酶活性均有显著影响。取食苍耳和酸模叶蓼有利于亚洲玉米螟的生长发育。玉米螟在不同寄主植物上的生长发育和繁殖与保护酶活性呈现正相关性。亚洲玉米螟在取食不同寄主植物时,能调节自身保护酶的活性,来适应寄主,满足生长发育的需要。     

苯甲酰脲类杀虫剂对亚洲玉米螟生长发育和繁殖的效用

为全面评价苯甲酰脲类(BPUs)杀虫剂对亚洲玉米螟Ostrinia furnacalis(Guenée)的持续控制作用,采用叶片浸渍法,测定氟啶脲、除虫脲、氟铃脲和虱螨脲对亚洲玉米螟生长发育和繁殖的影响。结果表明,经4种BPUs处理后,亚洲玉米螟存活幼虫的历期延长了2.4～4.3d,平均单头雌、雄蛹重分别减轻了10.3～13.2mg和0～7.7mg,幼虫化蛹率和成虫交配成功率分别下降了14.1%～43.3%和5.6%～25.6%,产卵量降低了25.5%～53.3%,但卵孵化率没有明显改变。亚洲玉米螟雌、雄蛾吸食蔗糖水药液后,成虫寿命增加了1.3～4.3d,产卵量下降40.3%～58.2%,卵孵化率降低了32.9%～64.3%,F1代幼虫死亡率是对照组的3.5～8.5倍,表明苯甲酰脲类杀虫剂显著抑制了亚洲玉米螟幼虫生长发育和成虫的繁殖力。     

中华食蜂郭公虫的生物学特性和行为观察

中华食蜂郭公虫Trichodes sinae Chevrolat是西鄂尔多斯地区重要传粉昆虫火红拟孔蜂Hoplitis pyrrhosoma Wu的寄生性天敌。文章报道中华食蜂郭公虫除成虫外各虫态的形态特征、生活史及幼虫和成虫的行为等生物学特性。该虫在西鄂尔多斯地区1年发生1代,越冬幼虫于4月上旬开始化蛹,5月中旬陆续羽化出巢,成虫取食植物补充营养后,开始交尾、产卵。1龄幼虫能够寻找并钻入火红拟孔蜂的巢室,取食火红拟孔蜂幼虫,直至结茧化蛹。室温条件下,卵期约6~8d,幼虫期约260~280d,蛹期约40~50d;雄虫寿命约28~30d,雌虫寿命约35~40d。     

棉铃虫不同虫态及虫龄血淋巴中酚氧化酶活力的比较

分别测定了棉铃虫Helicoverpa armigeraHübner不同虫态及虫龄血清和血细胞中酚氧化酶(phenoloxidase,PO)的活力。结果显示血清和血细胞中都有酚氧化酶活性,且血细胞中高于血清中。不同虫态及虫龄的血清和血细胞中酚氧化酶活力有很大的不同,血清和血细胞中酚氧化酶活力变化规律一致。3龄幼虫酶活力最高,5龄幼虫最低。酶活力大小依次为:3龄幼虫>预蛹>4龄幼虫>蛹>5龄幼虫     

黄粉虫防卫物质苯醌的测定及其去除

采用分光光度法测定了黄粉虫的防卫毒素苯醌的含量。结果表明 :各虫态各性别的黄粉虫在不同发育阶段其苯醌含量均有不同 ,各虫态的苯醌含量随日龄而增大 ,雌蛹和雌成虫的苯醌含量均高于同一日龄的雄蛹和雄成虫。经刺激后各虫态的苯醌含量升高 2 0 72 %～ 41 64%,刺激后用水清洗的虫体其体内苯醌含量下降 88 2 7%～ 92 60 %;烘烤也可使苯醌大量挥发和分解 ,采用刺激 -水洗 -研磨 -烘烤工艺处理幼虫可清除 94 3 0 %苯醌 ,此法可为保障黄粉虫作为饲用昆虫的安全性提供依据     

椰心叶甲实验种群的生物学特性观察

自然温度条件下 ,椰心叶甲Brontispalongissima (Gestro) 1年可发生 3代以上 ,世代重叠 ,主要以成虫越冬。成虫平均寿命 1 5 6d ,最长达 2 3 5d ,雌雄性比为 1∶1 ;雌雄虫一生均可交配多次。成虫产卵期长 ,产卵不规则 ,单雌平均产卵 1 1 9粒 ,最多可达 1 96粒。飞行磨测定的初步结果表明 ,雌虫飞行能力比雄虫强 ,2 4h未取食成虫最远飞行距离可达 40 0多m ;成虫和幼虫均具有负趋光性、假死性。成虫 3～ 5d不取食、高龄幼虫 7d不取食仍存活。幼虫经历 4～ 5龄 ,在温度或寄主不适宜条件下 ,可进入 6～ 7龄 ,或提前化蛹 ,从卵到成虫羽化大约需 3 6～ 61d。     

不同寄主植物对小地老虎生长发育和保护酶活性的影响

通过室内饲养和生物化学测定,研究了白菜(Brassica campestris ssp.Pekinensis)、大豆(Glycine max Merrill)和玉米(Zea mays L.)3种寄主植物的营养差异及对小地老虎Agrotis ypsilon(Rottemberg)幼虫发育、成虫产卵、成活率及6龄幼虫体内超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活力的影响。结果表明:供试3种寄主植物的可溶性蛋白、可溶性糖和含水量差异显著。与取食玉米和白菜的个体相比,取食大豆的小地老虎幼虫历期、蛹期较短,分别为43.02 d和11.87 d;雌虫成虫寿命最长,为15.92 d;单雌产卵量最高,为936.67粒。但后代卵的孵化率以取食玉米的最低。取食3种寄主植物的幼虫和蛹的成活率由高到低依次为取食大豆>取食白菜>取食玉米。幼虫体内CAT活力没有显著差异,但SOD、POD活力由高到低依次为取食大豆>取食白菜>取食玉米。     

Antitumor activity of phenylene bridged binuclear bis(imino-quinolyl)palladium(II) and platinum(II) complexes

Antitumor effects of a known bis(imino-quinolyl)palladium(II) complex 1 and its newly synthesized platinum(II) analogue 2 were evaluated against human breast (MCF-7) and human colon (HT-29) cancer cell lines. The complexes gave cytotoxicity profiles that were better than the reference drug cisplatin. The highest cytotoxic activities were pronounced in complex 2 across the two examined cancer cell lines. Both compounds represent potential active drugs based on bimetallic complexes.     

Acid-base and copper (II) complexation equilibria of poly(inosinic)-poly(cytidylic)

The acid-base and copper (II) complexing properties of the heteropolynucleotide poly(inosinic)-poly(cytidylic) acid were studied by means of potentiometric, spectrophotometric, CD, and molecular fluorescence titrations in a working aqueous medium of 0.15 M ionic strength at 37°C. The study of the acid-base equilibria has proved the existence of four different species in the pH interval 2–11. Two new species are detected in the presence of copper(II) ion, at acidic and neutral pH values. Spectrophotometric, CD, melting, and fluorescence data were treated with a multivariate curve resolution procedure that allowed the determination of the number of species simultaneously present in each system [acid-base equilibria, copper(II) complexation equilibria], and the estimation of their concentration profiles and of the pure spectra for each species. From the concentration profiles an unambiguous assignment of which species are present at any pH conditions can be made. Furthermore, the knowledge of the pure uv-visible, fluorescence, and CD spectra recovered by the proposed resolution method for each species brings important structural information. When this mathematical approach was applied to the thermal denaturation data, the melting profile and the uv pure spectra for all the different species or conformations formed in the melting process, were calculated. © 1997 John Wiley & Sons, Inc. Biopoly 42: 271–283, 1997     

芬兰真绥螨对苹果全爪螨的捕食作用研究

在实验条件下,系统研究了芬兰真绥螨Euseius finlandicus Oudemans对苹果全爪螨Panony-chus ulmi Koch的控制能力。研究结果表明:(1)在15～32℃的温度条件下,芬兰真绥螨雌成螨的捕食量随着温度的上升呈线型正相关。在15～25℃的温度内芬兰真绥螨的产卵量随温度升高而增加,在15℃下平均单雌产卵0.42粒,25℃时平均单雌产卵2.56粒;当温度升到32℃时单雌产卵下降为1.62粒,雌成螨的产卵量与温度的关系呈抛物线型。(2)在5～15头/叶的猎物密度下,雌成螨的捕食量随着猎物的密度增加呈线型正相关,而当猎物密度达到30头/叶时,芬兰真绥螨雌成螨的捕食量处于平稳状态。在5～15头/叶的猎物密度下,芬兰真绥螨的产卵量和产卵量均与猎物的密度呈线型正相关;当每头雌成螨捕食量为1.8～3.5头时,产卵量为1.0～1.5粒。(3)不同温度下,芬兰真绥螨对猎物的不同密度和虫态的功能反应可用圆盘方程II型进行拟合;在25℃条件下捕食效率最高且喜好捕食的虫态是卵和幼螨。     

真菌吸附铅锌的研究

正随着采矿业的迅速发展,越来越多的重金属通过多种途径进入土壤环境中,对生态环境造成了不可估量的破坏并严重威胁人类健康。铅锌在工业上具有非常重要的作用且其应用极为广泛,而他们具有的难去除、难迁移和生物累积等特性使得铅锌在环境中的污染尤为突出。通过微生物的生长代谢,有效降低土壤重金属毒性,是促进植物生长的重要步骤之一。同时也要求微生物自身具有抵抗重金属的功能,根际微生     

三种常见实蝇的形态学、生物学和生态学比较

对瓜实蝇Bactrocera (Tetradacus) minax (Enderlein)、桔小实蝇Bactrocera (Bactrocera) dorsalis (Hendel)和桔大实蝇Bactrocera (Zeugodacus) cucurbitae (Coquillett)的形态学、生物学、生态学等方面进行了比较和分析,包括三种实蝇在国内外的分布情况,对寄主选择的差异,各种虫态的形态特征,发育历期和生活史,并对它们的危害状况和防治方法分别作了介绍,可为3种实蝇的鉴定和防治提供参考.     

Synthesis and structural characterization of two new polynuclear metal thiosaccharinates: Hexakis(thiosaccharinato)hexasilver(I) and tetrakis(thiosaccharinato)tetracopper(I)

The title compounds, for short Ag₆(tsac)₆ (1) and [Cu₄(tsac)₄(MeCN)₂] · 2MeCN (2), were prepared by the reaction of thiosaccharin with Ag(I) or Cu(II) salts in different solvents. The new complexes were characterized by FT-IR, Raman, UV-Vis and NMR spectroscopy. Their crystal and molecular structures were determined by X-ray diffraction methods. The structures were solved from 1621 (1) and 7080 (2) reflections with I > 2σ(I) and refined to agreement R1-factors of 0.0261 (1) and 0.0456 (2). Ag₆(tsac)₆ molecule derives from the clustering of six Ag(tsac) moieties related to each other through the crystallographic 3-bar (S₆) symmetry operations of the space group. This results in a highly regular molecular structure where the silver atoms are at the corners of an octahedral core slightly compressed along one of its three-fold axis [inter-metallic Ag?Ag contacts of 3.1723(4) and 3.1556(4) Å]. The six thiosaccharinate ligands bridge neighboring Ag atoms along the C₃-axis through Ag-N bonds [d(Ag-N) = 2.285(2) Å] at one end and bifurcated Ag-S(thione)-Ag bonds [Ag-S distances of 2.4861(7) and 2.5014(8) Å] at the other end. In contrast, the 2 compound is arranged in the lattice as an irregular tetrameric copper complex [Cu₄(tsac)₄(MeCN)₂] where the metals show different environments. Two copper ions are four-fold coordinated to three tsac ions through the N-atom of one tsac [Cu-N distances of 2.112(3) and 2.064(3) Å] and the thione sulfur atom of the other two [Cu-S distances in the range from 2.284(1) to 2.358(1) Å] and to a MeCN solvent molecule [Cu-N distances of 1.983(4) and 2.052(3) Å]. The other two copper ions are in three-fold environment, one trans-coordinated to two tsac ions [Cu-N distances of 1.912(3) and 1.920(3) Å] and to the thione S-atom of a third ligand [d(Cu-S) = 2.531(1) Å], the other one to the thione sulfur atom of three tsac ligands [Cu-S distances in the range from 2.229(1) to 2.334(1) Å]. The clustering renders the metals to short distances from each other, the shorter Cu?Cu distance being 2.6033(7) Å, as to presume the existence of weak inter-metallic interaction within the cluster.     

Poly(etheno ADP-ribose) blocks poly(ADP-ribose) glycohydrolase activity

Poly(ADP-ribose) is a biopolymer synthesized by poly(ADP-ribose) polymerases. Recent findings suggest the possibility for modulation of cellular functions including cell death and mitosis by poly(ADP-ribose). Derivatization of poly(ADP-ribose) may be useful for investigating the effects of poly(ADP-ribose) on various cellular processes. We prepared poly(etheno ADP-ribose) (poly(epsilonADP-ribose)) by converting the adenine moiety of poly(ADP-ribose) to 1-N(6)-etheno adenine residues. Poly(epsilonADP-ribose) is shown to be highly resistant to digestion by poly(ADP-ribose) glycohydrolase (Parg). On the other hand, poly(epsilonADP-ribose) could be readily digested by phosphodiesterase. Furthermore, poly(epsilonADP-ribose) inhibited Parg activity to hydrolyse ribose-ribose bonds of poly(ADP-ribose). This study suggests the possibility that poly(epsilonADP-ribose) might be a useful tool for studying the poly(ADP-ribose) dynamics and function of Parg. This study also implies that modification of the adenine moiety of poly(ADP-ribose) abrogates the susceptibility to digestion by Parg.     

Immobilization of Cu(II) and Cr(IV) in basidiomycete-colonized sawdust

An investigation into the feasibility of removing Cu(II) and Cr(IV) from solution with basidiomycete (Gloeophylum sepiarium, Pleurotus sp.)-colonized sawdust was undertaken. Obeche (Triplochyton scleroxylon) sawdust exposed to the basidiomycetes for 1–3 months reduced the concentration of the metals in the solution to 22.0–84.4 mg/l. The supernatant from the centrifuged mixture of a solution of 100 mg metal ions/l and aqueous extract of a 3-month basidiomycete-degraded obeche sawdust contained lower concentration of the metal ions (38.6–75.4 mg/l). Unextracted sawdust of pigmented tropical timbers, African mahogany (Khaya ivorensis), black afara (Terminalia ivorensis) and camwood (Baphia nitida) exposed to the test basidiomycetes, removed Cu and Cr significantly better than the extracted sawdust. It is hypothesised that some products of basidiomycete wood-degradative activities were ligands which immobilized the test metals.     

Cu(II) and Zn(II) ions alter the dynamics and distribution of Mn(II) in cultured chick glial cells

Previous studies revealed that Mn(II) is accumulated in cultured glial cells to concentrations far above those present in whole brain or in culture medium. The data indicated that Mn(II) moves across the plasma membrane into the cytoplasm by facilitated diffusion or counter-ion transport with Ca(II), then into mitochondria by active transport. The fact that 1–10 M Mn(II) ions activate brain glutamine synthetase makes important the regulation of Mn(II) transport in the CNS. Since Cu(II) and Zn(II) caused significant changes in the accumulation of Mn(II) by glia, the mechanisms by which these ions alter the uptake and efflux of Mn(II) ions has been investigated systematically under chemically defined conditions. The kinetics of [⁵⁴MN]-Mn(II) uptake and efflux were determined and compared under four different sets of conditions: no adducts, Cu(II) or Zn(II) added externally, and with cells preloaded with Cu(II) or Zn(II) in the presence and absence of external added metal ions. Zn(II) ions inhibit the initial velocity of Mn(II) uptake, increase total Mn(II) accumulated, but do not alter the rate or extent Mn(II) efflux. Cu(II) ions increase both the initial velocity and the net Mn(II) accumulated by glia, with little effect on rate or extent of Mn(II) efflux. These results predict that increases in Cu(II) or Zn(II) levels may also increase the steady-state levels of Mn(II) in the cytoplasmic fraction of glial cells, which may in turn alter the activity of Mn(II)-sensitive enzymes in this cell compartment.     

Interferon induction by platinum(II)-poly(I)·poly(C) complexes

The effect of the interaction between poly(I)·poly(C) and cis-dichloro-diammineplatinum(II) (cis-Pt), its trans analogue and chloro-diethylene-triamminoplatinum(II) (dien-Pt) on interferon induction activity was investigated. The covalent monodentate fixation of the three compounds on N⁷ of inosine has different effects on the structure and thermostability of poly(I)·poly(C) which is well reflected by the interferon induction activity of the samples. Thus, the sandwich stabilization by dien-Pt at low binding ratios is manifested by an increased interferon induction and a high resistance towards RNAase degradation. The destabilization of the duplex by cis-Pt decreases interferon induction, accompanied by an increase in RNAase sensitivity of the complexes. In the case of trans-Pt the duplex structure is little perturbed and interferon induction is essentially maintained.