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1.
本文研究了棉铃虫雄蛾味刷中几种醇类物质对同种雄蛾行为反应的抑制效应。剂量范围从4×10-4到40μg的风洞剂量试验表明,当剂量为0.4μg,Z9-16∶Ald与Z11-16∶Ald两种混合物的比率为5∶95时,雄蛾有最高反应。当Z11-16∶OH加到上述混合物中,5%的醇浓度完全抑制定向行为。百分率进一步增加,不仅抑制定向行为,同时也影响起飞行为。将Z11-16∶OH与其他三种饱和醇14∶OH,16∶OH,18∶OH以及与结构上相似的Z9-16∶OH比较发现,Z11-16∶OH抑制雄蛾定向的行为最有效。田间施用Z11-16∶OH使其卵孵化率从处理前的34%降低到处理后的17%。  相似文献   

2.
Abstract The inhibitory effects of several alcohols identified from male hairpencil of cotton bollworm on conspecific male behavior responses were studied. In the wind tunnel dose tests ranging from 4 × lop4 to 40 pg, male moths of cotton bollworm produced the highest response to the binary components of 29–16: Ald and Z11 —16: Ald in a ratio of 5 : 95 at the dosage of 0.4 μg. When 211–16:OH was added to 0.4 μg dose of binary blend, 5% of the alcohol completely inhibited male orientation behavior. Further increment of percentage of alcohol in binary blend inhibited not only orientation behavior but also takeoff behavior. Comparisons among 211 —16: OH and other three saturated alcohols, 14 : OH, 16 : OH, and 18 : OH as well as structurally similar compound Z9–16: OH indicated that Z11–16: OH was more effective in inhibiting male orientation behavior than other tested alcohols. Field application of 211–16: OH decreased egg hatch rate from untreated 34% to 17% by spraying or coating the alcohal on plastic tubes.  相似文献   

3.
采用毛细柱气相色谱分析、酸性甲酯化反应和GC-MS证实等手段对棉铃虫雄蛾味刷抽提物进行了结构鉴定。从中鉴定了10种化合物。这些化合物是14:0H,14:Ac,14:COOH,Z11-16:OH,16:0H,16:COOH,16:Ac,18:OH,18:Ac和18:COOH。对各种化合物进行定量分析的结果表明,3种饱和醇在味刷中所占比例高达75%以上。味刷内化合物含量与雄蛾日龄有关,羽化10h以内的雄蛾味刷中不含以上鉴定的各种化合物,经过48h,雄蛾味刷中化合物的量达到高峰,在5日龄以后,化合物含量明显下降。  相似文献   

4.
室内测定增效剂940对棉铃虫的增效作用   总被引:1,自引:0,他引:1  
本以山东聊城,江苏徐州、泗阳和南京地区的棉铃虫为试虫,采用点滴法、浸溃法和喷雾法,于室内测定了增效剂940对拟除虫菊酯类的溴菊酯、氰戊菊酯、功夫菊酯和氯氰菊酯,有机磷类的久效磷、毒死蜱、辛硫磷、棉安磷,有机氯类的硫丹,复配剂辛灭(辛硫磷、灭多戚)乳油、灭杀毙(马拉硫磷、氰戊菊酯)、辛磷(辛硫磷、磷胺)乳油、功久(功夫菊酯、久效磷)乳油和甲辛(甲基对硫磷、辛硫磷)乳油的增效作用。结果表明:(1)940对上述药剂均有显或极显的增效作用,其增效谱很广;(2)940对上述四地区的棉铃虫均有显增效作用,其对抗性和敏感性棉铃虫同样有效;(3)940对棉铃虫3龄、4龄、5龄和6龄幼虫同样有增效;(4)无论在有机相中还是在水相中,940的增效性能均十分稳定;(5)以上性质表明了增效剂940在棉铃治理中具有巨大的潜能。  相似文献   

5.
The purines 6-amino-2-hydroxypurine and 6-amino-8-hydroxypurine, not normally associated with purine degradation in algae, were isolated by high-pressure liquid chromatography from cell extracts of Prototheca zopfii Krüger grown with adenine as the sole nitrogen source .  相似文献   

6.
Abstract  Lysiphlebus fabarum (Hymenoptera: Aphidiidae) is a generalist parasitic wasp species which can oviposit in several aphid species, including the bean aphid, Aphis craccivora (Homoptera Aphidinae), and the soybean aphid, A. glycines . The response of female L. fabarum and one of its host aphid species, A. glycines , to odors of undamaged host food plant (UD), mechanically damaged host food plant (MD), aphid-damaged plant (AD+, with aphid on, and AD˜, aphid washed off), and host aphid alone were studied in a wind tunnel. The positive orientation frequency of L. fabarum , which emerged from Aphis craccivora , to AD+ and AD˜ was significantly greater than to the UD, MD. Similarily, L. fabarum that emerged from A. glycines significantly flew more often to AD+ than to UD and aphid alone. And there was no significant difference among the positive response frequency of L. fabarurn to UD, MD, and aphid alone. All these suggested that herbivore feeding induced the attraction of the damaged plant to natural enemy of herbivore. It is also found that the condition of soybean seedling, being damaged or undamaged, did not have direct impact on host plant location of aphid.  相似文献   

7.
The claim that Chlorella sp. (CCAP 211/8p), sometimes referred to as C. fusca, Shihira and Krauss, does not excrete glycolate has been reexamined. Chlorella sp. grown on 5% CO2in air, excreted glycolate when incubated in light in 10 mM bicarbonate. Excretion ceased 30–60 min after transfer of the cells to air and no excretion could be detected with air-grown cells or with cells grown on 5% CO2in media buffered at pH 8.0. Incubation with 10 mM isonicotinyl hydrazide, a glycolate pathway inhibitor, caused excretion in air-grown cells and stimulated excretion in CO2-grown cells indicating that both the rate of glycolate synthesis and metabolism is higher in CO2grown cells than in air-grown cells. Enhanced glycolate synthesis and excretion in CO2-grown cells is correlated with law photosynthetic rate in 10 mM bicarbonate, and the photosynthetic rate of these cells doubles over a period of 2–2.5 h after initial transfer from high CO2to bicarbonate. This correlation of photosynthetic induction with cessation of glycolate excretion is similar to that reported in a bluegreen alga and thought to occur in other green algae. These results indicate that glycolate excretion and its regulation in this species of Chlorella is not different from that in other algae.  相似文献   

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9.
Abstract  A new species, Sinophasma largum sp. nov., is described from China (Sichuan, Guizhou, Hunan, Hubei and Guangxi Provinces). The type specimens are kept in the Institute of Zoology, Academia Sinica.  相似文献   

10.
Two species of blue-green algae Anabaena flosaquae and Oscillatoria sp. were shown to assimilate glycolic acid. In the presence of DCMU in light, approximately 50% of it wax oxidized to carbon dioxide; 90% was oxidized in the dark. Glycolate assimilation was increased fivefold by lowering the pH of the medium from 9.0 to 5.0, and the rate of uptake increased with increasing concentration of exogenous glycolate up to a saturation concentration of 12–14 mM. α-Hydroxysulfonates markedly inhibited glycolate uptake and oxidation but iso-nicotinyl hydrazide had little effect. These results indicate that glycolate oxidation occurs in vivo, but that the glycolate pathway in these algae differs some-what from that of higher plants.  相似文献   

11.
棉铃虫齿唇姬蜂的生物学特性   总被引:1,自引:0,他引:1  
研究了湖南长沙地区棉铃虫齿唇姬蜂的生物学特性及田间消长规律,棉铃虫齿唇姬蜂在湖南长沙地区年发生约10代,以7个世代发生在棉田,田间出现3个寄生高峰,分别在5月上旬-6月下旬,8月中旬-9月上旬及9月中旬-10月中旬,寄生率平均在25,1-63,1%,从卵发育到成虫的平均历期变化范围在32℃下13天至11.6℃下75.5天,棉铃虫齿唇姬蜂能寄主棉铃虫,斜纹夜蛾和甜菜夜蛾,但偏爱寄主棉铃虫。该蜂能寄生棉铃虫1-3龄幼虫,很少寄生4-6龄幼虫,喜寄生2-3龄幼虫,每雌可寄生斜夜蛾2龄幼虫5-23头。本建立了发育速率及成蜂寿命与温度关系的回归模型,探讨了越冬问题,比较了长江流域和黄河流域铃虫齿唇姬蜂生物学特性的差异。  相似文献   

12.
Abstract The bionomics of Campoletis chlorideae and the regularity of its seasonal fluctuations were studied in Changsha district, Hunan province. Field investigation indicated that there were ten generations of C. chlorideae a year, of which seven occurred in cotton fields. Three peaks of cotton bollworm parasitization by C. chlorideae were observed, early May to late June, mid August to early September, mid September to mid October respectively. One peak occurred in tomato and tobacco fields, the other two in cotton fields. The parasitization rate ranged from 25. 1 % ‐63. 1 %. The total development time from egg to adult ranged from 13. O days at 32°C to 75. 5 days at 11. 6 °C. Each wasp could parasitize the 5–23 second instar larvae of tobacco caterpillar. C. chlorideae could parasitize the cotton bollworm, beet armyworm and tobacco caterpillar, but preferred the cotton bollworm larvae. C. chlorideae could parasitized 1st‐ 3rd instar larvae of the tobacco caterpillar, but seldom parasitzed 4th ‐ 6th instar larvae. Moreover, C. chlorideae preferred second instar larvae. Theoretical models for developmental speed, adult longevity and the influence of temperature were proposed. The overwintering of C. chlorideae Uchida was also discussed. Moreover, methods for utilization of C. chlorideae Uchida in crop protection were presented and the bionomics of Curyoletis chlorideae in both the Yangtze River Valley and Yellow River Valley were compared.  相似文献   

13.
Closterium strains obtained from Japan ( NIES-64 and -65 ) and Nepal ( NIES-67 and -68 ) have been classified as the same taxonomic species; however, they are sexually isolated from each other. When NIES-64 and -65 cells were separately incubated in a medium in which both strains had previously been cultured together, release of protoplasts from both strains was observed. We suggest that factors responsible for the release of protoplasts from cells of both NIES-64 and -65 are produced in a mixed culture of these cells and function during conjugation. These factors, however, had no effect on the release of protoplasts from cells of strains NIFS-67 or -68. Alternatively, a protein that is responsible for the release of protoplasts from cells of NIES-68, called the protoplast-release-inducing protein ( PR-IP ), had no effect on the release of protoplasts from cells of strains NIES-64 or -65. When the media obtained from the culture of NIES-64 and -65 cells at various mixing ratios were analyzed by western blotting with antiserum to a 42-kDa subunit of PR-IP, no cross reaction was detected. In Southern hybridization analysis, no hybridizing band was observed when genomic DNAs of NIES-64 and -65 cells were probed with cDNAs encoding the two subunits of PR-IP. We suggest from these results that the factors responsible for the release of protoplasts from NIES-64 and -65 cells are not structurally similar to PR-IP. It is known that the release of PR-IP from NIES-67 cells can be induced by the action of another sex pheromone ( PR-IP inducer ) which is released by NIES-68 cells. In contrast, no protoplast-release-inducing activity was observed from either NIES-64 or -65 in a culture medium conditioned by opposite strains. We suggest that the conjugation systems employed by strains NIES-64/ NIES-65 and strains NIES-67 /NIES-68 differ, and we propose a possible mechanism of sexual isolation between these biological species .  相似文献   

14.
Excretion of minerals by the NaCl-resistant and comparatively cadmium-resistant tree Tamarix aphylla (L.) Karst, was investigated. Cd2+ was excreted by plants exposed for 1–10 days to 9 or 45 μ M Cd2+ solutions. Excretion of this toxic ion increased considerably with time but was less than 5% of the quantities that had been accumulated in the shoots. Excretion of Na+ and Cl was positively correlated with NaCl concentration (1.5, 10, 50 m M ) of the medium. The Na+/Cl ratios of the excrete were positively correlated with the concentration of the treatment solution. Ca2+ excretion decreased with increasing NaCl concentrations of the solution. Excretion of K+ and Mg2+ was only little affected by NaCl. Excretion of Li+ occurred whenever this element was supplied in the uptake solution; daily excretion rates of Li+ increased with time. The ecological significance of excretion is discussed in relation to the low selectivity of the mechanism in T. aphylla .  相似文献   

15.
GM1 ganglioside binding to the crude mitochondrial fraction of rat brain and its effect on (Na+, K+)-ATPase were studied, the following results being obtained: (a) the binding process followed a biphasic kinetics with a break at 50 nM-GM1; GM1 at concentrations below the break was stably associated, while over the break it was loosely associated; (b) stably bound GM1 activated (Na+, K+)-ATPase up to a maximum of 43%; (c) the activation was dependent upon the amount of bound GM1 and was highest at the critical concentration of 20 pmol bound GM1 X mg protein-1; (d) loosely bound GM1 suppressed the activating effect on (Na+, K+)-ATPase elicited by firmly bound GM1; (e) GM1-activated (Na+, K+)-ATPase had the same pH optimum and apparent Km (for ATP) as normal (Na+, K+)-ATPase but a greater apparent Vmax; (f) under identical binding conditions (2 h, 37 degrees C, with 40 nM substance) all tested gangliosides (GM1, GD1a, GD1b, GT1b) activated (Na+, K+)-ATPase (from 26-43%); NeuNAc, sodium dodecylsulphate, sulphatide and cerebroside had only a very slight effect. It is suggested that the ganglioside activation of (Na+-K+)-ATPase is a specific phenomenon not related to the amphiphilic and ionic properties of gangliosides, but due to modifications of the membrane lipid environment surrounding the enzyme.  相似文献   

16.
Abstract: Tyrosine hydroxylase (TOH), the rate-limiting enzyme in catecholamine biosynthesis, is regulated by phosphorylation. Activation of histaminergic H1 receptors on cultured bovine adrenal chromaffin cells stimulated a rapid increase in TOH phosphorylation (within 5 s) that was sustained for at least 5 min. The initial increase in TOH phosphorylation (up to 1 min) was essentially unchanged by the removal of extracellular Ca2+. In contrast, the H1-mediated response was abolished by preloading the cells with BAPTA acetoxymethyl ester (50 µ M ) and significantly reduced by prior exposure to caffeine (10 m M for 10 min) to deplete intracellular Ca2+. Trypticphosphopeptide analysis by HPLC revealed that the H1 response in the presence or absence of extracellular Ca2+ resulted in a major increase in the phosphorylation of Ser19 with smaller increases in that of Ser40 and Ser31. In contrast, although a brief stimulation with nicotine (30 µ M for 60 s) also resulted in a major increase in Ser19 phosphorylation, this response was abolished in the absence of extracellular Ca2+. These data indicate that the mobilization of intracellular Ca2+ plays a crucial role in supporting H1-mediated TOH phosphorylation and may thus have a potentially important role in regulating catecholamine synthesis.  相似文献   

17.
The polymerase chain reaction (PCR) was used to amplify eubacterial small-subunit (16S) ribosomal DNA (rDNA) genes from galls of the marine red alga Prionitis lanceolata Harvey (Gigartinales). These tumors consist of hypertrophied algal cells containing large numbers of intercellular bacteria that remain uncultivable. PCR-amplified 16S rDNAs from surface-sterilized gall tissue plugs were cloned, sequenced, and analyzed by alignment to available small-subunit rRNA sequences (University of Illinois Ribosomal Database Project). Variable regions were identified and used to construct a fluorescently labeled, species-specific oligodeoxynucleotide probe for whole cell in situ hybridization to the gall symbiont. Probe 949 (PLANC.949) localized the P. lanceolata bacterial symbiont in preparations from mature gall tissue. This probe did not hybridize to the rDNA of closely related bacteria included as controls in the same hybridization reactions, In situ hybridization revealed the presence of the same bacterium in association with P. lanceolata gall formation from three central California localities. Distance and parsimony analyses suggest that this organism is a member of the Proteobacteria (alpha subdivision; Rhodobacter group) and is most closely related to Roseobacter denitrificans .  相似文献   

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20.
—Some basic kinetic properties of adenylate cyclase in cell free preparations of mouse neuroblastoma were investigated. Production of cAMP from ATP by the enzyme requires the presence of either Mg2+ or Mn2+ in addition to ATP. In the presence of Mg2+, the Km for ATP is 120 ± 15 μM and the interaction of ATP and adenylate cyclase appears to be non-cooperative (Hill coefficient of 1). Magnesium ion concentrations in excess of the ATP concentration cause stimulation although similar excess concentrations of Mn2+ cause inhibition. Prostaglandin E1 and 2-chloroadenosine activate the enzyme. The Km of the cyclase for 2-chloroadenosine is 6 μm . Activation by 2-chloroadenosine leads to an increase in Vmax but does not effect the Km for ATP. At a fixed ATP concentration, the extent of activation caused by prostaglandin E1 and 2-chloroadenosine is inversely related to the Mg2+ concentration. Calcium ion causes inhibition of adenylate cyclase from 0.1 to 4mM with a Ki of 5 ± 10?4m . Ca2+ interaction with the enzyme in the absence or presence of either 2-chloroadenosine or prostaglandin E1 appears cooperative (i.e. Hill coefficients of ?2). Ca2+ inhibition is non-competitive with respect to either ATP or 2-chloroadenosine but is progressively diminished by increasing Mn2+ concentrations. Divalent cation effects and activation by 2-chloroadenosine and prostaglandin E1 of the neuroblastoma adenylate cyclase are compared with ion effects and hormone activation of the enzyme obtained from non-neuronal tissue.  相似文献   

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