昆虫病原微生物对其寄主行为的调控作用研究进展

昆虫病原微生物是调控昆虫种群数量动态的重要因子,其作为生物防治害虫的重要手段被广泛应用。昆虫病原物往往通过调控其寄主行为来提高自身的适应性,而有些寄主行为的改变却是其应对病原物侵染的免疫反应。发烧行为被证明可抑制病原增殖并延长寄主死亡;取食行为变化影响病原物或寄主的适应性;繁殖行为主要表现在产卵力、交配行为和性信息素等方面的变化;社会性行为改变对整个社会群体的适应性或病原物传播有影响;病原物所引起的寄主防卫和群集能力下降被认为对病原传播不利;病虫趋光和趋地行为、顶峰行为和活体寄主传病行为等被认为是病原物操纵的有利于病原微生物扩散和传播的行为。明确昆虫病原物调控其寄主行为的策略和机制对于寻找到新的害虫防治方法有指导意义。     

昆虫杆状病毒若干基因的研究进展

昆虫杆状病毒 (Ｉｎｓｅｃｔｂａｃｕｌｏｖｉｒｕｓ)对鳞翅目、双翅目和膜翅目等昆虫具有病原性 ,是一种开发应用较广、高效的生物杀虫剂 ,具有杀虫专一、效果好、有流行传播作用等优点。为了更好地利用昆虫杆状病毒为防治农林害虫服务 ,加快昆虫杆状病毒杀虫剂研究的步伐 ,本     

昆虫杆状病毒若干基因的研究进展

昆虫杆状病毒(Insect baculovirus)对鳞翅目、双翅目和膜翅目等昆虫具有病原性,是一 种开发应用较广、高效的生物杀虫剂,具有杀虫专一、效果好、有流行传播作用等优点.为 了更好地利用昆虫杆状病毒为防治农林害虫服务,加快昆虫杆状病毒杀虫剂研究的步伐,本文归纳了近几年来有关昆虫杆状病毒基因研究进展供从事研究的人员参考.     

苹果蠹蛾的综合防控和遗传控制研究进展

苹果蠹蛾是仁果类水果的重要检疫害虫,在世界各地造成了巨大的经济损失。目前对其化学防治、化学生态调控、病毒等防治方法研究较多,但仍不能满足防控该害虫的需要,对新型防控技术的需求日益增强。不育昆虫释放技术(SIT)是一种可控制甚至根除靶标害虫的环境友好型防控技术,但传统SIT技术存在一定的局限性,如较难区分性别与筛选雌雄虫、辐射不育昆虫的交配竞争力和适合度降低等问题,这些缺陷随着昆虫遗传修饰技术的发展将得以解决,并将在害虫防控进程中起到积极作用。本文综述了苹果蠹蛾主要防控技术研究现状,介绍了通过遗传修饰技术改善SIT的技术策略,并综合分析了我国开展苹果蠹蛾遗传修饰研究情况和将其应用在苹果蠹蛾防控体系中的可行性及优势。     

医学昆虫的病原真菌*

昆虫病原真菌在自然环境中对害虫数量起着抑制作用,在害虫的微生物防治中也占有独特的地位。长期以来,在应用昆虫病原真菌防治人畜害虫方面研究进展较为缓慢,六十年代以来才有较大的发展。本文介绍了近十年的发展概况,并讨论了影响这个研究领域迅速发展的原因及病原真菌在生物防治中应用的潜力。认为尽管至今对这类真菌了解还较少,但通过今后加强有关方面的研究工作,其应用前景是广阔的。     

医学昆虫的病原真菌

昆虫病原真菌在自然环境中对害虫数量起着抑制作用,在害虫的微生物防治中也占有独特的地位。长期以来,在应用昆虫病原真菌防治人畜害虫方面研究进展较为缓慢,六十年代以来才有较大的发展。本文介绍了近十年的发展概况,并讨论了影响这个研究领域迅速发展的原因及病原真菌在生物防治中应用的潜力。认为尽管至今对这类真菌了解还较少,但通过今后加强有关方面的研究工作,其应用前景是广阔的。     

遗传控制技术在实蝇类害虫中的研究进展

实蝇类害虫严重危害多种水果和蔬菜,是世界果蔬产业最重要的害虫类群之一,严重影响了发生地的果蔬生产和出口贸易活动。昆虫不育技术(SIT)是一种物种特异和环境友好型防治措施,在多种实蝇类害虫的防治、阻截和根除中起到了不可替代的重要作用。通过分子生物学技术对昆虫的基因组进行遗传修饰,可对SIT进行改进,提高其防控效果并扩大应用的物种范围,近年来相关方面的研究已取得重要进展,成为害虫遗传控制的研究热点。本文阐述了通过受四环素调控的tet-off基因表达系统来实现昆虫"不育"的基本原理和在果蝇及其他几种主要实蝇类害虫中建立的不同类型的遗传控制体系,以及类似体系在其他农业昆虫中的应用情况。简要介绍了在橘小实蝇遗传控制技术体系构建方面的工作进展,并对该技术的在害虫综合治理(IPM)尤其是实蝇类害虫防治中的应用前景进行了讨论和展望。     

应用昆虫病原线虫防控白蚁的研究现状

昆虫病原线虫是防治白蚁极具潜力的生物杀虫剂,但其在白蚁防控中的应用效果有待进一步研究。本文综述了昆虫病原线虫及其共生细菌在白蚁防治中的应用研究进展,探讨了昆虫病原线虫防治白蚁应用存在的关键问题,并对其未来的研究方向进行展望。     

21世纪我国害虫生物防治研究的进展、问题与展望

害虫生物防治是昆虫学的重要分支学科,进入21世纪以来,随着生命科学和生物技术的发展以及新原理、新方法的不断渗透、交叉与融合,使该分支学科在我国得到了快速发展。本文就近年来我国在天敌昆虫及其利用、昆虫病原微生物及其利用、昆虫信息素及其应用、生物农药及其推广应用、新兴生物技术在害虫生物防治中的应用等方面所取得的主要进展作了简要的回顾与总结;并在分析我国本领域学科发展水平与国际差距的基础上,指出了我国生物防治领域存在的主要问题及几个亟待加强的优先发展领域。     

昆虫病原微生物在储藏物害虫防治中的研究与应用

储藏物害虫的病原微生物包括病原细菌、真菌、病毒和病原原生动物等.本文综述了储藏物害虫病原微生物的研究与应用概况,并就病原微生物防治与其它防治方法的兼容作了简要概述,以期为储藏物害虫的生物防治提供参考.     

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

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.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

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     

Selection with two alleles and complete dominance

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.