双去甲氧基姜黄素对朱砂叶螨的生物活性及作用方式

在室温26℃±1℃、湿度60%～80%、光照14 h条件下,测定了天然植物活性成分双去甲氧基姜黄素对重要植食性害螨朱砂叶螨各螨态的触杀和熏蒸活性,对幼螨、若螨、成螨的驱避活性,以及对雌成螨的产卵抑制活性.采用玻片浸渍法测得双去甲氧基姜黄素对朱砂叶螨雌成螨48 h的LCso为0.433 mg·mL-1.在0.883 mg·mL-1(LC70)的浓度下,双去甲氧基姜黄素对朱砂叶螨不同螨态触杀活性的大小依次为幼螨＞若螨＞成螨＞卵,其中对幼螨24h和48 h的校正死亡率分别为60.0%和83.3%;对朱砂叶螨各螨态的熏蒸作用不明显,024h和48 h的校正死亡率均小于3%;对幼螨、若螨以及成螨均表现出较强的驱避作用,其中对幼螨的效果最好,不同处理时间的驱避率均在85%以上,其次是若螨,对成螨的驱避性相对较差,72 h的驱避率仅为47.8%.同时对雌成螨有明显的产卵抑制作用,处理后120 h产卵抑制率达到89.3%.表明双去甲氧基姜黄素对朱砂叶螨的主要作用方式为触杀、驱避和产卵抑制作用.     

薇苷菊提取物对桔全爪螨的产卵驱避作用及有效组分分析

使用甲醇、乙酸乙酯、乙醚提取薇苷菊 Mikania micrantha H.B.K.地上部植株并测试 3种提取物对桔全爪螨 Panonychuscitri Mc Gregor产卵的驱避作用 ,结果发现这些提取物处理后 1d都有显著的产卵驱避效果 ,其中极性最强的甲醇提取物效果最好 ,处理后 1d的产卵驱避率为 74 .2 2 %。用乙醚、乙酸乙酯、正丁醇、水依次对薇苷菊甲醇提取物进行萃取 ,生测结果表明只有极性最强的水萃取物具有显著的产卵驱避效果。进一步研究发现薇苷菊甲醇提取物经柱层析分离得到的 6个组分中有 3个对桔全爪螨有显著的产卵驱避作用 ,但效果都不及提取物 ,说明薇苷菊对桔全爪螨的产卵驱避作用是各组分共同作用的结果。用GC- MS对最有效组分的分析表明 :2 ,2′-亚甲基双 (6 -叔丁基 - 4 -甲基 )苯酚是含量最大的成分 ,占 70 .2 4 % ,β-谷甾醇和岩藻甾醇也是有效成分 ,但含量较低 ,分别占 12 .0 3%和 5 .6 1%     

东莨菪内酯对朱砂叶螨的驱避和产卵抑制活性

本研究采用叶碟浸渍法测定了东莨菪内酯对朱砂叶螨Tetranychus cinnabarinus(Biosduvals)雌成螨的触杀活性,采用选择性的半叶法测定了驱避活性,同时采用非选择性的全叶法测定了产卵抑制活性。结果表明,东莨菪内酯对朱砂叶螨雌成螨具有较好的触杀活性,采用叶碟浸渍法处理48h后的LC50为0.297mg·mL-1,LC30为0.105mg·mL-1,LC10为0.023mg·mL-1。采用LC50、LC30和LC103个浓度的东莨菪内酯处理雌成螨后,发现东莨菪内酯对雌成螨没有表现出明显的驱避活性,处理区和对照区24h和48h的着螨率均为50%左右;采用LC50和LC102个浓度处理雌成螨后表现出了一定的产卵抑制活性,平均产卵抑制率分别为23.02%和13.23%,而LC30对雌成螨的产卵量表现出了促进作用,平均产卵抑制率为-8.25%,这可能是由于毒物兴奋效应所致。本研究旨在为东莨菪内酯的进一步开发和应用奠定理论基础。     

生防放线菌Fq24代谢产物对朱砂叶螨的生物活性

菌株Fq24是从健康番茄植株分离得到的一株植物内生放线菌.为了研究它对朱砂叶螨生物活性的影响,通过萃取、柱层析、气相色谱-质谱(GC-MS)等技术对Fq24代谢产物中的杀螨活性物质进行了分离和结构鉴定,并采用玻片浸渍法和叶片残毒法测定了这些代谢产物的生物活性.结果表明:石油醚萃取物对朱砂叶螨具有较强的触杀和产卵忌避作用.触杀作用的LC50为52.57 mg·L-1,产卵忌避作用的ODC50为43.18 mg·L-1.经GC-MS分析,流份S11的主要化学成分为棕榈酸甲酯,分子式为C17H34O2,是代谢产物中的杀螨活性物质之一.质量浓度为5 mg·mL-1的棕榈酸甲酯对雌成螨的24h校正死亡率为78.3％,对雌成螨24h产卵驱避率为81.6％.     

16种植物乙醇提取物对桔全爪螨的生物活性测定

测定了16种植物乙醇提取物对桔全爪螨成螨的产卵忌避、驱避及毒杀生物活性。试验结果表明,海芋、山苍子及盐肤木茎叶的乙醇提取物有明显的产卵忌避作用,忌避率在96.43%以上;山苍子、枫香植物乙醇提取物对桔全爪螨成螨的驱避作用明显,驱避率在80%以上;山苍子、盐肤木茎叶、牡荆和幌伞枫提取物对桔全爪螨成螨的毒杀效果明显,在处理72h后,死亡率在92%以上。     

迷迭香油和花椒油对朱砂叶螨的生物活性

【目的】明确室内条件下迷迭香油和花椒油对朱砂叶螨Tetranychus cinnabarinus(Boisduval)的生物活性。【方法】采用熏蒸法和驱避法测定迷迭香油和花椒油对5日龄朱砂叶螨雌成螨的熏蒸活性、产卵抑制活性和驱避活性;并采用Etho Vision XT6分析亚致死浓度下两种精油对雌成螨行为的影响。【结果】分别将5日龄雌成螨熏蒸处理12,24和48 h后,迷迭香油对朱砂叶螨的致死率均显著高于花椒油处理组(P0.05),且随着熏蒸时间的延长或精油浓度的升高,其熏蒸活性均增强;不同浓度的迷迭香油处理朱砂叶螨雌成螨24 h后的产卵抑制率均显著高于花椒油处理组(P0.05)。迷迭香油和花椒油处理朱砂叶螨雌成螨24 h的LC_(30)分别为6.731和120.142μL/L;迷迭香油对朱砂叶螨雌成螨的驱避活性明显高于花椒油处理组。两种精油亚致死浓度处理朱砂叶螨雌成螨后,其自发运动方式发生了明显变化,移动频率在LC_(10)时呈现最高;且迷迭香油对朱砂叶螨雌成螨自发运动能力的影响比花椒油处理的影响更为明显。【结论】迷迭香油对朱砂叶螨的生物活性明显高于花椒油,因此,迷迭香油对朱砂叶螨的生物防治具有较高的应用价值。本研究为绿色蔬菜植物源杀螨剂的研究提供了科学依据。     

水菖蒲超临界CO_2萃取物对德国小蠊的触杀和驱避活性

水菖蒲(Acorus calamus L.)超临界CO2萃取物对德国小蠊Blattella germanica L.同时具有很好的触杀和驱避活性。采用药膜接触法和滤纸药膜选择法,分别研究水菖蒲超临界CO2萃取物对德国小蠊3龄若虫的触杀和驱避活性。结果表明:水菖蒲超临界CO2萃取物对德国小蠊的生物活性存在着明显的浓度-时间-效应。触杀作用中处理试虫12h后,最高浓度124.00μg/cm2的校正死亡率就达到98.33%,24h后达到100%。试虫在处理12h后的LC50为36.45μg/cm2。驱避活性中,最高浓度815.28μg/cm2的驱避率为67.73%,驱避等级达到了Ⅳ级。     

小菜蛾经历"保卫德"后产卵选择行为的变化

植食性昆虫成虫对非寄主植物源驱避素的经历,可导致其对这类化合物产生习惯性反应或诱导嗜好性.让小菜蛾雌蛾对源于印楝的驱避剂——“保卫德”(BIOACT-T^TM EC508)经历2～6次或2～6日后,测定它们对经过保卫德处理的白菜植株的产卵选择行为.结果表明,保卫德对2日龄、4日龄、6日龄无经历雌蛾均有很强的驱避作用,它们在经过保卫德处理的白菜植株上的相对产卵率均只有10%左右;对保卫德有2次或2 d经历的2日龄雌蛾,该产卵率平均上升到17%;对保卫德有4次或4 d经历的4日龄雌蛾,该产卵率上升到21%～24%;对保卫德有6次或6 d经历的6日龄雌蛾,该产卵率上升到29%.表明经历可导致雌蛾对保卫德产生习惯性反应或诱导嗜好性,使保卫德的驱避作用下降,但这种经历导致的产卵选择行为变化在个体之间存在较大差异.     

多炔类化合物对亚洲玉米螟产卵驱避作用及玉米螟的触角电位反应

以茵陈二炔为结构母体,人工合成了11个多炔类化合物。采用蜡纸接卵法,测定了11 个化合物对亚洲玉米螟Ostrinia furnacalis的产卵驱避活性。结果表明: 当处理浓度为20 μg/cm²时,受试的化合物对亚洲玉米螟的产卵行为具有一定程度的驱避作用,其中化合物9（1-苯基-4-甲基-丁二炔）对亚洲玉米螟产卵驱避作用明显, 调查处理后的3天、4天、 5天和6天,其产卵驱避率分别为85.71%、80.00%、61.27%和62.51%。触角电位测定表明,受试的11个化合物对亚洲玉米螟成虫触角感受器具有刺激作用,其中化合物6和化合物9能强烈地刺激产生高振幅的动作电位。10 mg/mＬ浓度处理,测得化合物6触角电位相对值, 雌、雄虫分别为68.22% 和106.60%,化合物9分别为199.19% 和220.60%。经回归分析所测11个化合物的产卵驱避活性与触角电位反应相对值,两者呈现一定程度上的相关性。还讨论了合成的多炔类化合物对亚洲玉米螟可能的作用靶标和结构与活性间的关系。     

十二种药用植物乙醇提取物对谷蠹和赤拟谷盗成虫的驱避效应

采用滤纸药膜选择法研究了蛇床子、茵陈、萹蓄等12种药用植物乙醇提取物对谷蠹Rhizopertha dominica(Fab.)和赤拟谷盗Tribolium castaneum Herbst成虫的驱避效应。12种药用植物以蛇床子(Cnidium monnieri)提取物对谷蠹成虫的驱避效果最佳,786μg/cm2处理24h对谷蠹的驱避率达93%;茵陈(Artemisia capillaries)提取物对赤拟谷盗成虫的驱避效果最佳,用393μg/cm2处理72h的驱避率为95%,茵陈提取物以262μg/cm2放置7d后对赤拟谷盗成虫的驱避率可达Ⅴ级水平。茵陈提取物对赤拟谷盗的驱避持效期长、效果好,具有一定的开发前景。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

The mechanism of hatching of eggs of Haemonchus contortus

Fluid collected from hatching eggs of Haemonchus contortus contained a lipase which hydrolysed 2-naphthyl laurate (about 0·7 μmol naphthol freed /h/10⁶ eggs). The fluid also hydrolysed l-leucinamide (about 2·3 μmol leucine freed/h/10⁶ eggs). The fluid when added to normal or heated eggs caused ‘hatching’. ‘Hatching’ also occurred in exsheathing fluid from infective juveniles and in a preparation of pancreatic lipase containing leucine aminopeptidase. A purified mammalian leucine aminopeptidase in combination with several different lipases did not attack egg shells.The ‘spontaneous’ hatching of eggs of H. contortus was strongly inhibited by 1,10-phenanthroline, 10^?3M, and this inhibition was reversed by Zn²⁺. However, the inhibition of ‘hatching’ of eggs in externally applied hatching fluid, or the hydrolysis of leucinamide in hatching fluid was generally less marked.