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1.
李虎  王晓贝 《昆虫知识》2007,44(4):I0003-I0004
金绿宽盾蝽Poecilocoris lewisi Distant在北京1年1代,以5龄若虫在侧柏(Platycladus orientalis Franco)附近的落叶和石块下越冬,翌年4月上中旬陆续从越冬处爬出,取食侧柏嫩叶。5月中旬5龄若虫开始羽化,6月初为羽化高峰期,6月中下旬羽化期结束,5月到8月为成虫期,7月底到8月中旬交配产卵,8、9月份若虫由1龄发育至5龄,9月中下旬为5龄若虫高峰期,11月5龄若虫开始转移越冬。  相似文献   

2.
南京地区卫矛矢尖蚧unaspis euonymi Comstock一年发生3代.第一至三代若虫孵化盛期分别为5月中旬、6月下旬和8月中旬.各代雌成虫始见期分别为5月下旬,6月下旬和8月下旬.11月下旬开始以受精雌成虫在寄主上越冬.主要天敌有红点唇瓢虫Chilocorus kuwanae Silvestri、日本方头甲Cybocephalus nipponicus Enduody-Younga,黄蚜小蜂Aphytis sp.等.药剂防治用机油乳剂。冬季1:30-50倍液(防治越冬代雌成虫),夏季1:50-100倍液;40%氧化乐果1:1000倍液、25%亚胺硫磷乳剂1:800倍液等喷洒1至3代盛孵若虫,杀虫效果均可达95%以上.  相似文献   

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【目的】葡萄穴粉虱是近年来入侵新疆吐鲁番地区的一种新害虫,明确其在新疆吐鲁番地区的生物学特性及发生危害情况,可为防治策略的制定提供科学依据。【方法】通过室内观察和田间调查,了解葡萄穴粉虱的形态学特征及生物学特性。【结果】葡萄穴粉虱属过渐变态。成虫复眼红棕色,翅膀表面覆盖白色蜡粉。卵倒锥形。若虫共4龄,扁椭圆形,体缘有蜡丝,末龄若虫在体壳内化蛹。4龄若虫(拟蛹)有半透明和黑色2型,越冬型4龄若虫(拟蛹)为黑色且有金属光泽。该虫在吐鲁番1年发生3~4代。越冬代成虫于4月上中旬破蛹羽化,开始在葡萄园危害,5月中旬第1代若虫孵化,5月下旬为孵化高峰;6月中旬2代若虫开始孵化,6月下旬—7月初为孵化高峰,世代重叠严重,10月中下旬之后以越冬代蛹在枯叶和枯枝上越冬。除为害葡萄外,葡萄穴粉虱还危害五叶地锦等葡萄科植物。【结论】在葡萄冬季埋土前或春季上架时,清除枯枝落叶可以大量减少越冬虫源,减轻防治压力。5月中旬第一代若虫孵化高峰期是化学防治的关键时期。在重点开展葡萄园防治的同时,应加强对五叶地锦等园林植物的防治。  相似文献   

4.
徐龙江 《昆虫学报》1980,(3):304-304
糖槭蚧Parthcnolecanium corni (Bouche)近年来在新疆为害葡萄、苹果、桃、杏、核桃、酸梅、巴旦、械、白蜡、杨、柳等多种植物,并猖獗漫延。 此蚧虫一年发生1-2代,通常以2—3龄若虫在嫩枝或树皮裂缝处越冬。翌年4月下旬或5月上旬为雄虫羽化期,5月中旬雌成虫产卵,卵于5月底或6月初孵化,孵化盛期为6月中旬,6月下旬孵化  相似文献   

5.
黑刺粉虱及其天敌的研究   总被引:12,自引:1,他引:11  
黑刺粉虱Aleurucamhus spiniferus Quaint.是柑桔、茶树等经济作物的重要害虫。福建一年发生4-5代,闽北、闽中发生4代,世代重叠。主要以若虫在柑桔等叶背越冬,越冬若虫于翌年2月间开始化蛹(伪蛹),4月间成虫羽化并产卵。各世代若虫发生期为第一代4月上旬至6月上旬;第二代6月中旬至7月下旬;第三代7月中旬至9月上旬;第四代9月中旬至翌年3月,11月进入越冬期。一年中以6-9月为发生为害高峰期。黑刺粉虱的寄生性天敌和捕食性天敌资源丰富,蛹期被寄生率甚高,对该虫的综合治理可以生物防治为主要措施。  相似文献   

6.
祁连山林区云杉梢斑螟生物学特性及防治调查   总被引:2,自引:0,他引:2  
云杉梢斑螟以幼虫危害青海云杉新生的树梢和嫩叶,以1龄幼虫在当年新梢基部和针叶中越冬。次年5月中旬开始活动并危害新梢,6月中旬化蛹,6月底始见成虫,7月上旬末、中旬初达羽化高峰。7月中旬为产卵盛期。7月下旬幼虫孵化,幼虫轻微危害后于9月中、下旬进入越冬状态。6月中旬,用3%高渗苯氧威喷雾,防治效果均在90%以上;用森得保可湿性粉剂喷雾,防治效果85%以上;羽化期可利用黑光灯诱杀成虫。  相似文献   

7.
荔枝蝽2龄以内若虫不会传病.3,4和5龄若虫及成虫均会传病.获毒着虫蜕皮后的高一龄若虫或羽化后的成虫不经再饲毒也能传病.荔枝蝽在田间的传病虫态主要是成虫,龙眼鬼帚病原病毒在成虫体内的循回期为4天(或短于4天)至34天.生产上治虫防病的关键时期是越冬成虫恢复活动,进入交尾产卵期和春夏之交若虫盛发期开展化防。把荔枝蝽防治在羽化传病之前.  相似文献   

8.
白翅叶蝉(Thaia subrufa Motschulsky)在浙江省东阳县,一年大部发生二代。第一、二代成虫分别于6月下旬至7月上、中旬和8月下旬至9月中旬盛发于早稻和双季晚稻,第二代成虫大部分越冬,少数早发的才能发生第三代。第一、二和三代卵历期分别为17—19、11—12和15一19天,若虫历期分别为19、16和24天。成虫4℃开始活动,10℃开始取食,15℃开始羽化和产卵。卵开始发育温度在20℃左右。成虫无孤雌生殖现象,产卵前期在第一、二代分别为23和17天,越冬成虫则长达6—8月之久。每雌产卵量以越冬代最高,以后各代急剧下降。越冬后成虫在4月下旬几乎全部集中于早、中稻秧田,产卵盛期在5月即早稻本田分蘗期。繁殖寄主仅限于水稻。 因白翅叶蝉具有这些生物学特性,所以防治适期为早季秧田。1964—1965年在东阳县早季秧田大面积防治结果,可减低早、中稻本田虫口90%以上,且能压低双季晚稻田的虫口密度。  相似文献   

9.
<正> 麦水蝇Hydrellia sp.在西北地区和四川省的东北部地区为小麦上的常发性害虫。常年成虫在10—11月期间飞到小麦苗上产卵,幼虫蛀入叶鞘内为害。翌春2月下旬至3月中下旬羽化为第一代成虫;3月下旬至4月上中旬为幼虫主害时期,严重为害孕穗、抽穗期的小麦植株的上部叶鞘,4月中旬至5月上旬羽化为第二  相似文献   

10.
【目的】绿长突叶蝉是中国新纪录种,是危害新疆葡萄生产的新害虫,为明确其生物学特性,进行了调查研究。【方法】田间定点调查,悬挂粘虫板、糖醋液诱集,结合室内饲养观察等方法。【结果】室内饲养表明,若虫共5龄,各龄期的平均发育历期分别为3.88、6.31、5.16、5.28、7.00 d;雌、雄成虫平均寿命分别为9.5和6.4 d。田间观察表明,绿长突叶蝉以卵在寄主葡萄上越冬,在新疆玛纳斯一年发生3代,越冬代卵于4月底开始孵化,5月下旬越冬代开始孵化为成虫;第1代卵从6月中旬开始孵化,7月中旬若虫开始羽化;第2代从8月初开始,一直持续到10月底;成虫主要在夜晚21点至23点及凌晨6点至8点活动。【结论】绿长突叶蝉一年发生3代,以卵越冬;若虫共5龄,具有较强的趋嫩性;成虫有较强的趋黄性,一定的趋光性,趋蓝性较弱,对糖醋液无趋性。试验结果可为葡萄安全生产,防治绿长突叶蝉提供理论依据。  相似文献   

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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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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   

18.
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   

19.
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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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   

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