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中国新疆地区粉虱种类(半翅目:粉虱科)记述 总被引:2,自引:0,他引:2
记述了新疆地区粉虱5属6种,即欧洲甘蓝粉虱Aleyrodes proletella(Linnaeus),葡萄穴粉虱Aleurolobus shantungi Tang,非洲小粉虱Bemisia afer(PriesnerHosny),烟粉虱Bemisia tabaci(Gennadius),桑粉虱Pealius mori(Takahashi),温室白粉虱Trialeurodes vaporariorum(Westwood),其中葡萄穴粉虱为新疆新记录种。并且用扫描电镜对其伪蛹进行拍照,并依据玻片标本进行了描述。编制了新疆地区粉虱分类检索表。 相似文献
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粉虱拟青霉对黑刺粉虱的侵染过程 总被引:3,自引:0,他引:3
本文通过扫描电镜和透射电镜 ,观察了粉虱拟青霉对黑刺粉虱的侵染过程。用粉虱拟青霉分生孢子接种于黑刺粉虱幼虫后 ,12h孢子萌芽 ,36h菌丝穿透寄主表皮进入体腔 ,在虫体内进行生长繁殖 ,逐渐充满虫体内部 ,5d后 ,菌丝穿透寄主表皮长出体外 ,并继续生长 ,逐渐将整个虫体包裹 ,形成一个半球形的子痤 ,颜色也由白色变为栗褐色或棕红色。 相似文献
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螺旋粉虱Aleurodicus dispersus是广泛分布于热带和亚热带地区的重要入侵害虫。为了揭示其在海南对低温的耐性,通过测定低温致死中温度、致死中时间分析各个虫态的耐寒性。低温致死中温度由低到高的顺序为3龄若虫、1龄若虫、卵、2龄若虫、成虫和4龄若虫,分别为5.33℃、5.43℃、7.38℃、7.96℃、10.69℃和13.75℃;在3℃低温下卵至4龄若虫的致死中时间从长到短的顺序为3.74 d(卵)、2.11 d(3龄)、1.74 d(2龄)、1.21 d(1龄)和1.16 d(4龄)。在3℃时螺旋粉虱成虫大量快速死亡,其在12℃时的致死中时间为1.02 d。螺旋粉虱卵对低温的忍受能力较强,成虫对低温的忍耐力最弱。低温暴露下的死亡率用于评价螺旋粉虱的耐寒性更有现实意义。 相似文献
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通过比较研究茶黑刺粉虱 Aleurocanthus camelliae Kanmiya & Kasai和樟刺粉虱 Aleurocanthus cinnamomi Takahashi形态特征,有助于更好地区分这两种刺粉虱种类。采集这两种粉虱标本,通过体视显微镜和扫描电镜对茶黑刺粉虱和樟刺粉虱不同龄期形态结构进行了系统观察和比较研究;同时将伪蛹制作玻片标本观察。茶黑刺粉虱和樟刺粉虱卵、1 龄若虫和2 龄若虫形态结构比较相似,但是伪蛹形态不同,刺的数量及分布有较大的区别。茶黑刺粉虱中央区隆起,尤其是管状孔区域更明显,位于一个凸起的瘤突上;亚缘区上有10 ~ 11 对刺排列,樟刺粉虱亚缘区具有刺14 对,其中头胸部5 对,腹部9 对。茶黑刺粉虱管状孔隆起,亚心形或近圆形,盖瓣心形,几乎充塞了整个管状孔区域;樟刺粉虱管状孔半圆形,盖瓣半圆形,充塞管状孔一半区域。两种刺粉虱成虫整体上比较相似,复眼、胸部和腹部及前翅基部为橙黄色;前后翅及身体上的白色粉状物都是由后足将腹部蜡盘分泌物覆盖上的,茶黑刺粉虱的粉状物比樟刺粉虱要多。前后翅上有不同形状的白色斑纹,左右翅斑相连,但是樟刺粉虱前翅后缘全白,而茶黑色粉虱前翅后缘仅有部分白斑。本研究结果有助于更好地区分樟刺粉虱和茶黑刺粉虱,为农林生产过程中准确鉴定和防治提供一定的参考资料。 相似文献
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螺旋粉虱的生物学特性 总被引:24,自引:1,他引:24
螺旋粉虱Aleurodicus disperses Russell是一种新入侵海南的重要害虫。本文结合田间观察和室内实验, 对螺旋粉虱各虫态的形态特征及生物学特性进行了系统观察和研究。结果表明:螺旋粉虱世代的发育起点温度和有效积温分别为8.88℃和511.86日·度, 在海南一年可发生8~9代。在18~32℃恒温条件下, 螺旋粉虱世代发育历期为26.63~57.16 d, 其中卵期7.15~15.93 d, 1龄若虫期4.00~11.03 d, 2龄若虫期3.83~7.53 d, 3龄若虫期4.09~8.64 d, 拟蛹期7.56~14.03 d。在18~32℃条件下, 各虫态发育速率与温度呈抛物线关系, 但在18~28℃则为直线关系; 低温和高温都不利于其繁殖, 14℃恒温条件下无法完成世代发育。成虫不活跃, 活动有明显的规律性, 晴天活动多集中在上午, 阴天活动少, 雨天不活动。 相似文献
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记述粉虱科2中国新纪录种:木姜子棒粉虱Aleuroclava ayyari(Sundararaj&David)和扁担杆褶粉虱Aleurotrachelus grewiae Takahashi。用环境扫描电镜对其伪蛹进行拍照,并依据玻片标本进行描述和绘图。木姜子棒粉虱主要鉴别特征是在头部和第1腹节分别着生1对长的亚背区刚毛。扁担杆褶粉虱主要鉴定特征是蛹壳硬化,头尾两端较尖,腹部中央基部较圆。标本存放在扬州大学昆虫标本室。 相似文献
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Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis
It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis. 相似文献
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted. 相似文献
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肝癌中HBV和HCV基因和抗原的分布及意义 总被引:1,自引:0,他引:1
采用原位分子杂交方法检测HCV
RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV
RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV
RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV
X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV
C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细 相似文献
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment. 相似文献