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41.
鄂西特有植物提取物的杀虫活性   总被引:5,自引:0,他引:5  
首次报道悬铃木叶苎麻、龟背竹、李叶绣线菊、扇脉杓兰、鞘柄木、青牛胆、仙茅和大叶金腰的杀虫活性。质量分数为1%的(下同)千里光茎、李叶绣线菊花、龟背竹、扇脉杓兰茎叶、悬铃木叶苎麻和鞘柄木叶甲醇提取物对舍蝇Musca domestica vicinaMacquart 48 h的致死率在70%以上,其中千里光茎为96.55%。仙茅、扇脉杓兰和李叶绣线菊花对赤拟谷盗Tribolium castaneum(Herbst)种群60 d繁殖抑制率达50%以上,其中最高仙茅为83.52%。仙茅和李叶绣线菊花对赤拟谷盗30 d的毒杀率在60%以上。悬铃木叶苎麻对斜纹夜蛾Spodoptera lituraFabricius 3龄幼虫48 h的拒食率为84.00%。李叶绣线菊花、青牛胆、悬铃木叶苎麻和大叶金腰对亚洲玉米螟Ostrinia furnacalis(Guen?e)3龄幼虫具较好拒食效果,其中,李叶绣线菊花48 h对亚洲玉米螟3龄幼虫的拒食率为81.17%,这几种植物还引起试虫体重不增加、化蛹延迟、畸形蛹或部分蛹死亡现象。所筛选植物对致倦库蚊Culex pipiens quinguefasciatusSay 4龄幼虫48h的毒杀率均低于20%。以甲醇冷浸提取法对所采集的植物材料进行冷浸提取时,提取率分布在1.92%至12.92%之间。  相似文献   
42.
确定爵床科Acanthaceae叉柱花属Staurogyne的中越叉柱花S. petelotii Benoist和密花叉柱花S. vicina Benoist为中国新记录。  相似文献   
43.
Blowfly larvae (Diptera: Calliphoridae) fulfil an important ecological function in the decomposition of animal remains. They are also used extensively in forensic entomology, predominantly to establish a minimum time since death, or a minimum post-mortem interval, using the larval length as a 'biological clock'. This study examined the larval growth rate of a forensically important fly species, Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) at temperatures of between 4 degrees C and 30 degrees C, under controlled laboratory conditions. The laboratory flies had been trapped initially in London, U.K. The minimum developmental temperature was estimated to be 1 degrees C and 4700 accumulated degree hours (ADH) were required for development from egg hatch to the point of pupariation. Lines fitted to the laboratory larval growth data were found to adequately explain the growth of larvae in the field. The nature of variation in growth rates from geographically isolated populations is discussed.  相似文献   
44.
The significance of brushtail possum, Trichosurus vulpecula Kerr (Diprotodontia: Phalangeridae) carcasses to the succession and production of Diptera species and its relevance to fly strike management in Tasmania, Australia was examined. Calliphora stygia (Fabricius), Lucilia sericata (Meigen) and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) were found to be the most abundant and Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae) always the least abundant (< 1%) of the putative primary fly invading species to emerge. Carcasses that were left for up to 15 days in the field before being exposed to flies for 2 days also acted as breeding sites for large numbers of all primary fly species, with the exception of L. cuprina. Ordination analysis revealed no relationship between possum carcasses according to their length of exposure but did show significant negative associations between the number of putative secondary invaders (Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae), Chrysomya varipes (Macquart) (Diptera: Calliphoridae) and putative tertiary flies (Hydrotaea rostrata Robineau-Desvoidy (Diptera: Muscidae)) to the number of C. vicina or C. stygia to emerge. There was enormous variability in the numbers of secondary/tertiary fly species to emerge from carcasses (0-11 450) that negatively correlated with the proportion of all flies to emerge that were primary, and with the mean size of adult L. sericata. Although carcass temperatures, especially those with a large larval population, were elevated, this did not appear to result in significant pre-adult fly mortality. The most important primary fly strike species L. cuprina was only found in insignificant numbers, whereas three other members of the fly strike fauna C. stygia, L. sericata and Ch. rufifacies did use possum carrion as an important breeding resource, but left implications for fly strike management inconclusive.  相似文献   
45.
温度对大黑蚁存活率及其保护酶系影响的相关分析   总被引:1,自引:0,他引:1  
刘缠民  马捷琼 《四川动物》2006,25(4):796-797
在-10~45℃温度下分别养殖大黑蚁,观察其存活率和活动状况,测定不同温度下其SOD、POD、CAT保护酶活力。结果表明,在较低和较高温度下其存活率明显低于10~40℃。在40~45℃时,酶活性随着温度升高,急速下降;在-10~10℃时,酶活性随温度降低而下降。保护酶测定值和存活率与相应温度密切相关。  相似文献   
46.
The functional response of Cydonia vicina nilotica Muls. (Coleoptera: Coccinellidae) to six densities of Aphis craccivora Koch (Homoptera: Aphididae) nymphs on broad bean (Viciafaba Linn.) was investigated in the laboratory. A linear relationship between the rate of consumption and prey density was observed with r^2 values between 0.58 and 0.97. Plotting prey density against prey killed by four larval instars, and adult males and females of C. vicina nilotica fit well with the type Ⅱ model of Holling' s disc equation. Adult females consumed the highest number of prey, followed by fourth instars and adult males. Based on the functional response data, the model predicts a maximum of 144.9, 116.3, 86.2, 80.0, 72.5 and 20.0 nymphs to be consumed per day by an individual adult female, fourth instar, adult male, third, second and first instars, respectively. The differences in the responses of the predator to aphid densities are discussed.  相似文献   
47.
目的探讨罗非鱼、中华鳖胰岛细胞分离提取的方法及对比两者的生物学活性差异。方法采用胶原酶消化分离罗非鱼、中华鳖胰岛细胞,光镜下观察其形态结构。在体外用不同浓度的葡萄糖刺激胰岛细胞,测定其生物学活性。结果罗非鱼、中华鳖胰岛细胞在体外对不同浓度的葡萄糖刺激具有明确的生物学反应,并随着葡萄糖浓度的增加胰岛素的产生也相应增加。结论采用胶原酶消化分离罗非鱼、中华鳖胰岛细胞的方法可行,胰岛细胞在体外对不同浓度的葡萄糖刺激产生胰岛素并具有正相关,其为鱼纲、爬行纲与哺乳纲动物之间的胰岛细胞移植奠定了实验基础。  相似文献   
48.
Five microsatellite loci are presented for prickly acacia, Acacia nilotica ssp. indica (Benth.) Brenan, an introduced weed of national significance in Australia. These microsatellite loci were obtained through the construction of an enriched library and their use will enable us to determine the genetic origin and extent of genetic diversity of this weed in Australia.  相似文献   
49.
盐胁迫对榅桲组培苗生长及其生理特征的影响   总被引:3,自引:2,他引:1  
以榅桲组培苗为实验材料,采用不同质量分数的NaCl和Na2SO4处理后,观察盐胁迫对其生理生化指标的影响.结果表明:榅桲组培苗萌芽率、增殖倍数和平均株高均随2种盐质量分数的增大而降低,并在2种盐质量分数皆为1.0%时不再萌芽,平均株高降至试验最低值,而在NaCl和Na2SO4质量分数分别为0.8%和1.0%时不再增殖;榅桲组培苗叶片膜透性随着2种盐质量分数的增大而升高且与对照差异显著,并于盐质量分数为1.0%时均达到试验最大值,而当NaCl和Na2SO4质量分数分别为0.8%和1.0%时,组培苗致死率超过50%;组培苗叶片的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均随着2种盐质量分数的增大呈先上升后下降趋势,而过氧化物酶(POD)活性则随着2种盐质量分数的增加而持续增强.研究发现,盐胁迫榅桲组培苗的相关指标均与相应对照有显著差异,其中的叶片膜透性及其SOD、CAT以及POD均可作为鉴定榅桲耐盐性评价指标.  相似文献   
50.
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