黑翅土白蚁巢群觅食群体大小与工蚁体长呈正相关

【目的】明确黑翅土白蚁Odontotermes formosanus巢群的觅食群体大小与工蚁体长之间的关系,为进一步研究其生态学特点以及更好地开展防治提供依据。【方法】在杭州植物园内选择5处有黑翅土白蚁活动区域作试验点,诱捕并以中性红(neutral red)标记捕获的白蚁工蚁,通过“捕获-标记-释放-重捕”试验测定黑翅土白蚁的觅食群体大小。【结果】5个试验点中有4个成功实施了“捕获-标记-释放-重捕”试验,4个试验点黑翅土白蚁巢群的觅食群体个体数量分别为443 133±45 469, 495 360±67 429, 674 345±101 703和1 224 662±93 112头。黑翅土白蚁觅食群体大小(Y)与觅食工蚁的体长(X)呈正相关,拟合的指数函数方程式为：Y=1.8389e^0.7185X(R²=0.7834)。【结论】本研究明确了黑翅土白蚁的觅食群体大小以及工蚁体长之间的函数关系,为开展区域防治提供了依据。     

白蚁巢系破坏堤坝稳定性的研究

黑翅土白蚁Odontotermes Formosanus是我国南方诸省严重危害堤坝的主要白蚁种。它的巢居结构严重破坏土质堤坝工程,常常形成险情或“千里金堤,溃于蚁穴”。 我们的试验说明了黑翅土白蚁的巢居结构破坏堤坝工程的原理,为防治白蚁提供理论依据。     

黄翅大白蚁的分群孔图象与主巢方位的关系研究

前言 我国南方诸省危害土质堤坝的主要白蚁危害种,一般多为黑翅土白蚁Odontotermes formosanus(Shiraki),其次是黄翅大白蚁Macrotemes barneyi Light。然而也有些水库则以黄翅大白蚁为主,如广东湛江志满水库1982年据分群孔普查出黄翅大白蚁21巢,其中分群孔图象标记清楚的有12巢例;黑翅土白蚁只有一巢例;海南土白蚁7巢例;黄翅大白蚁占该坝白蚁危害种数的72.41％。 为提供堤坝白蚁找巢技术,从1978—1982年对黄翅大白蚁的分群孔分布图象与主巢方位的关系进行了研究。     

白蚁初期群体的形成及其行为的观察

家白蚁Coptotermes formosanus Skiraki和黑翅土白蚁Odontotermes formosanus(Skiraki)在我国是分布广,为害大的二种重要害虫。家白蚁危害建筑材料、房屋、橡胶、塑料、地下电缆、尼龙等有机合成材料,部分金属和农林作物,危害涉及到国民经济各个部门;而黑翅土白蚁严重地为害堤坝,我国南方各省水库堤坝为害率达53—92％,严重地区发生漏水的占20％,为害农林作物亦很严重。对它们的生物学和生态学特性及防治方法,国内外已有不少研究报道,但对它的生殖行为、孵化、脱皮习性,目前尚少有较系统的资料。因此,本试验试图通过家白蚁和黑翅土白蚁初期群体的形成,进行较详细的观察,为深入探讨白蚁的生物学和生态学特性提供真实依据。     

烯啶虫胺肠衣饵剂对黑翅土白蚁的防治效果

[目的]为了开发一种高效环保型白蚁饵剂.[方法]选定烯啶虫胺和溴虫腈对黑翅土白蚁Odontotermes formosanus进行室内毒力测定,根据室内毒力测定结果筛选毒力较高药剂进行驱避试验,并制备3种不同剂量的肠衣饵剂,开展室内白蚁毒杀效果试验和园林白蚁防治效果试验;选用合适剂量肠衣饵剂进行堤坝黑翅土白蚁诱杀试验,并用挖巢法检测肠衣饵剂对堤坝黑翅土白蚁的诱杀效果.[结果]1.6tg/mL烯啶虫胺处理黑翅土白蚁72 h后校正死亡率达100％,16 μtg/mL溴虫腈处理72 h后黑翅土白蚁校正死亡率也达到100％.室内毒力测定结果表明烯啶虫胺对黑翅土白蚁的LC5o值低于溴虫腈,100 μtg/mL烯啶虫胺处理8h后对黑翅土白蚁无显著驱避作用.3种剂量烯啶虫胺肠衣饵剂处理72 h后,黑翅土白蚁校正死亡率均在60％以上.将不同剂量的烯啶虫胺肠衣饵剂投放到园林中45 d后,肠衣饵剂基本被食空,施药点周围无白蚁及活动迹象.在福建省水库大坝周围投放60 μtg/g烯啶虫胺肠衣饵剂,3个月后肠衣饵剂未发霉且基本被食空,6个月后挖巢发现蚁道内无黑翅土白蚁活动,白蚁巢体出现死亡和坍塌情况.[结论]60 μg/g烯啶虫胺肠衣饵剂对园林和堤坝中的黑翅土白蚁具有良好的诱杀效果,是一种高效环保型白蚁肠衣饵剂.     

水库堤坝白蚁的防治研究

本工作是根据水库堤坝的生态环境特点,研究土牺白蚁中黑翅土白蚁[Odontotermes(O.)formosantts(Shiraki)]和黄翅大白蚁(Macrotermes barneyi Light)的分布情况、活动规律和防治措施,其中包括以黑光灯诱杀成虫和药剂灌巢。     

江苏镇江地区主要白蚁种类分布、危害状况及防治策略

【目的】本文旨在明确镇江市白蚁种类分布、危害状况和防治策略。【方法】本文按照镇江市人口密度和园林绿化分布特点,将全市划分为商住区、工业区、园林区三个主要不同的生态区域。通过2012—2013年两年时间的调查与数据收集,在各生态区域共采集185份白蚁标本。运用传统白蚁形态学分类和现代分子生物学技术相结合的方法,对镇江市白蚁主要危害种类进行了鉴别确认。根据白蚁危害严重程度的不同,将镇江市不同生态区域分为蚁害严重区、较重区、一般区,以此确定镇江市白蚁分布危害的特点。【结果】本研究鉴别确认了镇江市主要白蚁种类为2科4属共7种白蚁,分别为黑翅土白蚁Odontotermes formosanus Shiraki、黄翅大白蚁Macrotermes barneyi Light、台湾乳白蚁Coptotermes formosanus Shiraki、黑胸散白蚁Reticulitermes chinensis Snyder、尖唇散白蚁Reticulitermes aculabialis Tasi et Hwang、圆唇散白蚁Reticulitermes Labralis Hsia et Fan和黄胸散白蚁Reticulitermes flaviceps Oshima。根据镇江市主要白蚁种类危害发生空间生态分布情况,镇江市的白蚁危害面广,各区域都有不同程度发生,其中城中区域白蚁分布最为密集。黑胸散白蚁在各个生态区域均有危害分布,且分布范围最广。三个不同生态区域中,蚁害严重区都集中在商住区,且散白蚁危害较大。园林区多为蚁害较重区,且土白蚁危害比较突出。工业区多为白蚁危害一般区,其散白蚁和土白蚁危害程度基本相同。根据镇江市近5年主要白蚁种群及蚁害发生时间,镇江地区的白蚁危害在全年各个月份都有发生,其危害的高峰期主要集中在4—6月,在5月达到高峰值。【结论】通过系统研究与调查,我们掌握了镇江市的白蚁种类以及主要白蚁种群的生态分布区域,明确了镇江地区白蚁发生的时间规律、区域分布特征及其危害严重程度。以此为基础,本文提出了有针对性的镇江地区食木白蚁综合防治策略,为今后更有效地开展白蚁防治工作,保护珍贵园林树种及古典建筑,进一步提高我国白蚁防治和管理水平提供了有效的科学依据及其防治策略。     

不同温度对黑翅土白蚁初建群体的影响

黑翅土白蚁Odontotermes formosanus(Shiraki)是经济害虫之一,它常筑巢于水库和河堤的土质内危害堤坝,引起渗漏,甚至酿成塌堤垮坝,造成人民生命则产的严重损失。 外界环境温度对巢位深、巢体结构复杂、调节温湿度能力强的黑翅土白蚁成年巢群影响较小,但对入土筑巢位置浅、巢体结构简单的黑翅土白蚁初建巢群的生长、发育、繁殖、巢内白蚁个体数量变动等则影响较大。到目前止,国内外这方面的研究不多。本试验研究不同温度条件对黑翅土白蚁初建群体生长、发育、繁殖等方面的影响,这对深入了解其初建群体的生长发育规律及其初建巢群的控制方面有一定意义。     

黑翅土白蚁的跟踪信息素

黑翅土白蚁Odontotermes formosanus(Shiraki)严重危害堤坝,有明显跟踪行为,其分泌跟踪物质的腹板腺位于腹部第5节腹板前沿中部,分泌细胞呈长形,与腹板呈垂直方向排列。用滤纸双圈法测定黑翅土白蚁跟踪行为。跟踪物质的抽提以正己烷较好,丙酮和二氯甲烷次之。从抽提液柱层析、薄层层析和微化学反应结果推测,其跟踪物质可能是含有双键的醇类化合物。密褐褶孔菌及其感染的腐木块抽提液及白蚁跟踪信息化合物——顺,顺-3,6-十二碳双烯醇都对黑翅土白蚁有较强的跟踪活性。肖若散白蚁和家白蚁抽提液均对黑翅土白蚁有跟踪活性,但肖若散白蚁和家白蚁对黑翅土白蚁抽提液及其柱层析和薄层层析的活性馏份无活性反应。     

四种植物精油对黑翅土白蚁触杀和驱避作用

为筛选出高效防治黑翅土白蚁的天然植物精油,减少有机合成农药的使用,该文研究了大蒜精油、肉桂油、丁香油和印楝素油四种植物精油对黑翅土白蚁的触杀效果和驱避作用。结果表明:大蒜精油、肉桂油和丁香油的浓度为5和10 mg·m L~(-1)时,处理2 h后,黑翅土白蚁的校正死亡率达100%,而相同浓度的印楝素油和对照处理的黑翅土白蚁校正死亡率低于5%。随着处理时间延长,浓度为1.25和2.5 mg·m L~(-1)的大蒜精油、肉桂油和丁香油处理6 h时,黑翅土白蚁的校正死亡率仍达100%,而此时对应的印楝素油和对照处理的黑翅土白蚁校正死亡率仅为10%,说明大蒜精油、肉桂油和丁香油对黑翅土白蚁具有较强的触杀效果。大蒜精油、丁香油和肉桂油在处理黑翅土白蚁2 h后LC_(50)值(半致死量)分别为1.572、1.05和1.03mg·m L~(-1),说明肉桂油对黑翅土白蚁的毒性相对最大,触杀效果最好。此外,10 mg·m L~(-1)的大蒜精油、肉桂油、丁香油和印楝素油的驱避试验表明,处理4、6、8和12 h后,大蒜精油、肉桂油和丁香油三精油处理区的黑翅土白蚁数均显著低于对照区的,驱避率总体93%,而对应的印楝素油的驱避率总体28.5%,表明大蒜精油、丁香油和肉桂油三种植物精油对黑翅土白蚁均有显著的驱避活性。综上可知,四种植物精油中大蒜精油、肉桂油和丁香油在防治黑翅土白蚁方面应用潜力很好,是开发绿色环保白蚁防治药剂的可选材料。     

Field evaluation of a fipronil bait against subterranean termite Odontotermes formosanus (Isoptera: Termitidae)

The subterranean termite Odontotermes formosanus Shiraki is an important pest of agronomic crops, plantations, and forestry, and it endangers earthen dikes and dams in China. A fipronil bait consisting of straw pulp and white sugar was evaluated against field colonies of O. formosanus. Triple mark-capture with Nile blue dye was used to delineate foraging territories and to estimate foraging populations of four O. formosanus colonies locating in the campus of Huazhong Agricultural University, Wuhan, China. Termite activity was monitored by number of termite workers and straw board consumption in underground monitoring stations. Consumption of bait matrix and fipronil was estimated for each testing site. The results showed that approximately 3-5 mg of fipronil could suppress foraging populations of O. formosanus containing 0.4-0.7 million foragers per colony. Baits containing fipronil seem to be a feasible alternative for controlling O. formosanus.     

Effects of Soil Water Content on Biodegradation of Phenanthrene in a Mixture of Organic Contaminants

Phenanthrene biodegradation was investigated at different soil water contents [0.11, 0.22, 0.33, 0.44 g H₂O (g soil)^?1] to determine the effects of water availability on biodegradation rate. A subsurface horizon of Kennebec silty loam soil was used in this study. [9-¹⁴C] phenanthrene was dissolved in a mixture of organic contaminants that consisted of 76% decane, 6% ρ-xylene, 6% phenanthrene, 6% pristane, and 6% naphthalene, and then added to the soil. The highest rate of mineralization, in which 0.23% of the [9-¹⁴C] phenanthrene degraded to ¹⁴CO₂ after 66 days of incubation, was observed at the soil water content of 0.44 g H₂O/g dry soil. Most of the ¹⁴C remained in the soil as the parent compound or as nonextractable compounds by acetonitrile at the highest water content. Concentrations of nonextractable compounds increased with water content, but residual extractable phenanthrene decreased significantly with increasing water content, which presumably indicates that bio-transformation occurred. The mineralization analysis of radiolabeled 9th carbon in phenanthrene underestimated phenanthrene biodegradation. The strong adsorption and low solubility of phenanthrene contributed to the low mineralization of phenanthrene 9th carbon. The other components were subject to higher biological and abiotic dissipation processes with increasing soil water content.     

Haematology and serum chemistry parameters of the pregnant rat

This study describes the baseline haematology and serum chemistry values found in non-pregnant, pregnant (gestational days [GD] 2-21) and lactating (postnatal days 1-9) Sprague Dawley rats (n = 3-10/day) from the NCTR breeding colony of Crl:COBS CD(SD)BR strain. Maternal body weights on GD0 ranged from 250 to 300 g. Multiple analytes were measured in both whole blood and serum of dams. Amniotic fluid, fetal serum, and postnatal pup serum analyte values were also acquired. Maternal blood was collected from the heart under subterminal carbon dioxide (CO2) anaesthesia. Most pregnant dam blood values were not appreciably different from values for non-pregnant dams until near term; near-term values for some analytes (red blood cells, haemoglobin, haematocrit, mean corpuscular haemoglobin concentration, alkaline phosphatase, albumin, total protein, glucose, total bilirubin, sodium, and chloride) decreased but returned to near-normal values soon after delivery. The most dramatic change was a three-fold elevation of serum triglyceride levels near term with a subsequent decrease at birth. Most serum chemistry analytes measured in progeny increased after birth except for alkaline phosphatase, calcium and potassium levels which decreased.     

Dithiocarbamates and prevention of cadmium teratogenesis in the hamster

Certain dithiocarbamates (DTC) have been reported to protect against cadmium (Cd)-induced lethality and to decrease Cd body burden. The present study evaluated the influence of sodium N-benzyl-D-glucamine dithiocarbamate, sodium N-di(hydroxyethyl)amine dithiocarbamate, sodium 4-carboxyamidopiperidine-N-dithiocarbamate, and sodium N-methyl-D-glucamine dithiocarbamate on Cd-induced teratogenesis in the hamster. When given as a single ip injection at 2.2 mmol/kg 15 min prior to iv CdCl2 (2 mg/kg), all of the DTC afforded significant protection against Cd-induced developmental toxicity and reduced kidney [Cd] in the dam. Maternal liver [Cd] was reduced with the glucamine and dihydroxyethyl amine analogs, but treatment with the piperidine failed to influence hepatic [Cd]. Pretreatment of the dams with DTC 24 hr prior to Cd challenge failed to protect against Cd-induced embryotoxicity, and provided minimal, if any, reduction in renal or hepatic [Cd]. Pretreatment with the N-methyl-D-glucamine congener 24 hr prior to Cd exposure increased embryolethality. The dose-time relationships found here suggest that pharmacologically effective levels of these DTC decline within 24 hr of treatment and that induction of metallothionein does not play a major role in DTC antagonism of Cd poisoning.     

The Role of Glycerol and Inorganic Ions in Osmoregulatory Responses of the Euryhaline Flagellate Chlamydomonas pulsatilla Wollenweber

The green euryhaline flagellate Chlamydomonas pulsatilla Wollenweber, isolated from a coastal marine environment, was grown exponentially over the salinity range of 10 to 200% artificial seawater (ASW). The cellular volume and aqueous space of the alga, measured by [¹⁴C] mannitol and ³H₂O tracer analyses of centrifuged cell pellets, ranged between 2.3 and 3.1 picoliters and between 1.5 and 2.1 picoliters, respectively. The nonaqueous space determined in those analyses (28-35%) was consistent with the cell composition of the alga. The glycerol content of the alga increased almost linearly with increasing salinity; its contribution to intracellular osmolality at 200% ASW was about 57%. The contribution of amino acids and soluble carbohydrates to the cell osmotic balance was small. Intracellular ion concentrations determined by analyzing centrifuged cell pellets of known [¹⁴C]mannitol space by atomic absorption spectrophotometry, and by neutron activation analyses of washed cells were similar. At 10% ASW, potassium and magnesium were the major cations, and chloride and phosphate were the major anions. The sodium and chloride content of the alga increased with increasing salinity; at 200% ASW the intracellular concentration of both sodium and chloride was about 400 millimolar. The intracellular osmolality (π_int) matched closely the external osmolality (π_ext) over the entire salinity range except at 10% ASW where π_int exceeded π_ext by 120 to 270 milliosmoles per kilogram H₂O.     

Effects of hypergravity exposure on plasma oxytocin concentration in pregnant and lactating rat dams

Rat dams and offspring were exposed to 1.5-g, 1.75-g or 2.0-g hypergravity (hg) from Gestational day [G] 11 until Postnatal day [P] 10. To ascertain the role of maternal factors in reduced postnatal body weights of offspring developed in hg, the dams' lactational hormones were measured. Oxytocin (OT), the major hormone responsible for milk ejection, was reduced in hg dams whereas prolactin (Prl), involved in milk production, was unchanged. Video analyses of nursing behavior revealed that hg dams spent more time nursing relative to 1-g controls. We hypothesized impaired milk transfer from dam to pup, however pup body weight gains following a discrete suckling episode were comparable across conditions. Changes in lactational hormones and nursing behavior by dams exposed to hg do not account for reduced body masses of their offspring.     

Responses of Methanotrophic Activity in Soils and Cultures to Water Stress

Diffusive gas transport at high water contents and physiological water stress at low water contents limited atmospheric methane consumption rates during experimental manipulations of soil water content and water potential. Maximum rates of atmospheric methane consumption occurred at a soil water content of 25% (grams per gram [dry weight]) and a water potential of about -0.2 MPa. In contrast, uptake rates were highest at a water content of 38% and a water potential of -0.03 MPa when methane was initially present at 200 ppm. Uptake rates of atmospheric and elevated methane decreased when water potentials were reduced by adding either ionic or nonionic solutes to soils with a fixed water content. Uptake rates during these manipulations were lower when sodium chloride or potassium chloride was used to adjust water potential rather than sucrose. The response of methane consumption by soils to water potential was somewhat less pronounced than the response of methanotrophic cultures (e.g., Methylosinus trichosporium OB3b, Methylomonas rubra [= M. methanica], an isolate from a freshwater peat, and an isolate from an intertidal marine mudflat). However, unlike soils, methanotrophic cultures exhibited a stronger adverse response to nonionic solutes than to sodium chloride.     

硫化物抑制潮土反硝化过程中氧化亚氮还原的菌群机制

【背景】土壤中的反硝化作用形成气态产物N_2O和N_2,会导致氮素的气态损失,并造成温室效应。硫化物对土壤的N_2O还原具有抑制作用,但其对菌群和功能基因的影响机制还不清楚。【目的】研究有无外加碳源情况下,硫化物对反硝化作用中间产物(NO、N_2O)的积累、反硝化功能基因(narG、nirS、nirK和nosZ)表达量以及菌群结构的影响。【方法】分别设置不同量葡萄糖(0和1000mg-C/kg干重土壤)和硫化钠(0和150mg-S/kg干重土壤)添加的交叉处理,进行室内微宇宙培养实验,利用自动化培养与实时气体检测系统检测培养过程中NO、N_2O和N_2的积累量,通过反转录定量PCR测定反硝化功能基因表达量,利用MiSeq技术平台基于16S rRNA基因序列的高通量测序分析样品的菌群结构。【结果】硫化钠的添加显著抑制N_2O还原,但是其对于N_2O积累量没有显著影响,却显著降低了NO的积累量。硫化钠的添加短时间内在转录水平上显著抑制N_2O还原酶的活性,并且抑制固氮弧菌属(Azoarcus)、微枝形杆菌属(Microvirga)、剑菌属(Ensifer)、氮氢单胞菌属(Azohydromonas)、芽孢杆菌属(Bacillus)、斯科曼氏球菌属(Skermanella)、申氏杆菌属(Shinella)和西索恩氏菌属(Chthoniobacter)的基因转录,降低它们的转录本丰度,结合Kyoto Encyclopedia of Genes andGenomes(KEGG)数据库的查询结果,发现硫化钠的添加抑制了不产生N_2O的N_2O还原反硝化细菌的生长。【结论】堆肥或其他原因引起的土壤硫化物增加,导致反硝化过程N_2O还原被抑制的原因是由于其对氧化亚氮基因转录的抑制和对不同反硝化菌的选择作用,研究结果有助于认识硫化物对氮代谢影响的微生物机制。     

Biological half-lives of bromide and sodium in the rat are connected and dependent on the physiological state

The parallel course of the excretion rates of sodium and bromide ions was demonstrated in adult male rats administered simultaneously with ²⁴Na-sodium chloride and ⁸²Br-bromide. These excretion rates were inversely proportional to the magnitude of sodium intake in the animals. The biological half-life of bromide, as a substitute for sodium or chloride, was investigated with the aid of the radionuclide ⁸²Br in animals situated in very different physiological states (i.e., in lactating and nonlactating female rats as well as in young rats of varying ages [2,4,6, and 10 wk of age]). The ⁸²Br radioactivity retained in mothers and in whole litters was measured in vivo at appropriate time intervals (up to 240 h) after the application of ⁸²Br-bromide to the mothers. The time-course of the changes in the ⁸²Br radioactivity of the young was calculated as the difference between the rate of ⁸²Br intake in the mother's milk and the ⁸²Br excretion through the kidneys into the urine. The rate of ⁸²Br excretion through the kidneys of the dam could be calculated also. Nonweaned young rats (12 d) had the highest half-life (269 h) and lactating dams had the lowest (44 h). The determined values demonstrated that nonweaned young apparently conserve sodium, because of its relatively low concentration in mother's milk, whereas lactating dams, because of their large food intake, waste sodium. Presented in part at the 4th International Symposium on Trace Elements in Human: New Perspectives held in Athens (Greece) on 9–11 October 2003     

一株耐辐射新菌种的分离鉴定及其多糖的抗氧化研究

【目的】确定新疆辐射污染土样中分离筛选获得的一株产多糖的耐辐射菌株W36-1的分类学地位和抗氧化特性。【方法】对该菌株进行的60Co辐照,结合菌落形态和菌丝特征显微观察、Biolog鉴定以及16S rRNA基因序列分析。采用苯酚硫酸法测定其多糖含量,采用Fenton法测定多糖的粗提物对超氧阴离子清除率;用DPPH法测定抗氧化性;采用邻苯三酚自氧化法测定对超氧阴离子的清除率。【结果】W36-1可耐5 kGy辐照,为一株欧文氏菌属(Erwinia)新种;其粗多糖含量为53.17%,该多糖对超氧阴离子清除率为75.63%,对DPPH清除率为62.43%,羟基自由基去除率为54.89%。【结论】菌株W36-1产的多糖具有抗氧化性。