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1.
展缘异点瓢虫——一种捕食玉米螟卵的天敌   总被引:1,自引:0,他引:1  
展缘异点瓢虫(Anisosticta kobensis Lewis)在玉米、高粱、水稻、小麦、大豆及果树上均有发生。以玉米田的数量较大,盛期百株成虫70余头;其次是高粱、水稻;豆田、麦田、果树上的数量较小。该虫可捕食多种作物上的蚜虫及玉米螟卵。 展缘异点瓢虫在河南玉米上一年有两个成虫高峰。第一次出现在5月上旬,盛期为5月底至6且上旬,第二次在7月下旬,盛期在8月中旬。成虫产卵期为5~7天,产卵量30~50粒,散产或两列排布于玉米叶背,卵经3天孵化。在日均温23~28℃的室内条件下饲养,1、2龄幼虫各1天;3龄幼虫2~3天;4龄幼虫4~5天,整个幼虫期9~10天,蛹期3~4天。  相似文献   

2.
八点灰灯蛾Creatonotus translens(WalKer)是我区南宁、百色、河池三地区部分山区春玉米苗期的重要害虫,是新发现的玉米黑毛虫主要种类,作者于1980年在隆安县布泉公社田间调查时,发现有自然感病的死亡,死亡率10.8%,死亡幼虫多倒挂于石田硬的石壁上.死亡症状全身肿胀液化流出黄褐色液体;在室内饲养中也极易感染发病,死亡症状相同.经中国科学院上海生物化学研究所龚祖勋同志鉴定为核型角体病毒.试验结果表明,1~6龄幼虫均可感染而死亡.1~3龄幼虫接种后第4天开始发病死亡,接种后第7天死亡率达67.5-86.3%,第10天达75.0—90%,5~6龄幼虫于接种后第13天后化蛹前大量死亡,总死亡率93.3%.  相似文献   

3.
在室内用生测法研究了表达Cry1Ab杀虫蛋白的Bt玉米MON810和Bt11小苗和心叶对粘虫Mythimna separata (Walker)初孵幼虫以及玉米叶片对暴食期4龄和5龄幼虫的杀虫效果.结果表明,2种Bt玉米小苗及心叶对粘虫初孵幼虫都具有很好的控制效果,取食MON810和Bt11小苗的粘虫初孵幼虫第1 天的存活率分别为69.44%和86.11%,到第3 天时,取食Bt11小苗的幼虫全部死亡,此时取食MON810小苗的幼虫存活率仅为4.17%,到第7 天全部死亡,而此时在各自相对应的对照玉米DK647和NX4906小苗上幼虫存活率分别为91.66%和88.89%.取食MON810和Bt11心叶的粘虫初孵幼虫第2 天时幼虫存活率急剧下降,分别为13.89%和19.45%,到第7 天时,取食两种Bt玉米心叶的初孵幼虫全部死亡,而取食对照玉米心叶幼虫存活率分别为94.45%和97.22%,差异极显著.两种Bt玉米对粘虫4龄幼虫有很好的杀虫效果,取食的第11天 4龄幼虫全部死亡,对照幼虫存活率均为100%;在Bt11和MON810叶片上取食的粘虫5龄幼虫也不能存活,分别在取食的第11天和12天全部死亡,对照存活率分别为96.00%和98.00%,差异极显著.表明Bt玉米对粘虫初孵幼虫和暴食期的4龄和5龄粘虫都具有显著的致死作用.  相似文献   

4.
东方粉蝶是十字花科蔬菜上的重要害虫,在铜鼓县一年发生6—8代,以蛹越冬,卵期3—5天。幼虫期,第1代16—18天,第2~6代11—13天,第7~8代18—20天,11月为25天。蛹期5~10月中旬为7~10天,10月底~11月初为12~18天,越冬蛹128~174天,成虫寿命,雄为3—4天,雌为7—8天,产卵量150粒左右。文中对该虫的形态作了描述和绘图。防治时,给合人工捕采幼虫和卵粒,田间施药可用2.5%敌杀死剂2500—3000倍液、90%敌百虫1000倍液、50%马拉硫磷或敌敌畏800—1000倍液,防治效果很好。  相似文献   

5.
黄斑星天牛磷化氢熏蒸技术初步研究   总被引:2,自引:0,他引:2  
在 4 4~ 2 1 1℃系列温度条件下 ,磷化氢熏蒸黄斑星天牛 (Anoplophoranobilis)的毒力试验和室内验证试验结果表明 :4 4℃和 1 0 0℃的熏蒸时间为 5天 ,推算出死亡机率值 9要求的CT值分别为 6 2 9 81和 31 2 2 0mg·h/l,验证试验不能完全杀死黄斑星天牛或芳香木蠹蛾东方亚种 (Cossuscossusorientalis)和杨干透翅蛾 (Spheciasiningensis)幼虫 ;1 5 5℃和2 1 1℃的熏蒸时间为 4天 ,预计CT值分别为 :1 1 2 83和 36 59mg·h/l,室内验证实验证明 ,投药剂量为 2 2 6mg/l,熏蒸 4天能够全部杀灭杨树携带的黄斑星天牛幼虫和蛹 ,以及芳香木蠹蛾东方亚种和杨干透翅蛾幼虫。  相似文献   

6.
甘蔗二点螟的生物学与测报调查方法初探   总被引:1,自引:0,他引:1  
二点螟是我省甘蔗上的主要害虫。根据笔者多年的调查观察,本文报导甘蔗二点螟的生物学及测报调查方法。1甘蔗二点螟的生物学在我省,甘蔗二点螟一年发生4~5代,以老熟幼虫和少数低龄幼虫在宿根蔗残、残留蔗茎及秋冬笋枯南内越冬。越冬幼虫在3月底至4月下旬化蛹、羽化为成虫。各代幼虫主害时期:第一代4月底~5月下旬;第2代6月下旬~7月中旬;第三代7月下旬~8月中旬;第四代8月下旬~9月上旬。成虫多在夜晚羽化,白天躲避,晚间活动,靠雌蛾分泌性外激素,引诱雄蛾交尾;第二天晚上开始产卵,持续4~5d,产卵200粒左右。卵多产在l~4叶的…  相似文献   

7.
二点螟是甘蔗上的主要害虫。在江西省一年发生四代,以老熟幼虫和少数低龄幼虫在宿根蔗蔸、残茎内和秋冬笋枯苗上越冬;在3月下旬至4月下旬化蛹、羽化成虫。成虫在夜晚羽化,活动,白天隐避。产卵期持续4~5天,产200粒左右,一二代产卵在1~4叶的背面。成虫有趋光性,雌雄蛾量比为0.9:1.1。幼虫多在白天的上午从卵中孵出,先在叶面爬行,或垂丝下悬,随风飘动,主要从侧芽处侵入蔗苗,为害心叶,8~10天出现枯心苗。每只幼虫可造成1~3根枯心苗,老熟幼虫在苗内或茎内化蛹。  相似文献   

8.
新疆果树多毛小蠹生物学特性及防治   总被引:2,自引:0,他引:2  
多毛小蠹是新疆果树重要害虫,危害杏树甚为严重。在库尔勒一年发生2~3代,主要以幼虫和少数成虫、卵在树皮内越冬,世代重叠。在自然变温下,卵历期4~11天,幼虫20~31天;蛹期6~9天;成虫10~35天。完成一世代需40~86天,主要以幼虫在寄主树表面活动。采用农业和药剂防治相结合效果显著。  相似文献   

9.
铜绿金龟(虫甲)是北京地区的一种重要害虫,一年发生一代,以3龄幼虫在土壤51~75厘米深层越冬。成虫每年6~9月出现,成虫有较强的趋光性,一日内以19:30′~21:00′活动最盛。成虫食性杂,每一雌虫一生可产卵30~40粒。产卵期为4~5天。在9种含水量(0.3、2、4、6、8、10、15、20和25%)土壤与5种温度(10、17、25、30、37℃)组合下,试验结果卵在温度25℃与8~15%含水量土壤内孵化率最高。卵的发育起点温度是9.14±1.15℃,发育有效积温为178.05日度。幼虫季节性垂直分布与10厘米土温变化有关,秋季当10厘米土温低于10℃,幼虫向土壤深层迁移,春季当10厘米土温高于6℃幼虫向土壤表层迁移。每年4~5月及8~9月幼虫10厘米作物外进行为害,这时亦导防治的有利时机。  相似文献   

10.
转基因抗虫棉花对棉铃虫生长发育影响的系统评价   总被引:15,自引:1,他引:15  
以我国研制的转基因抗虫棉(Bt棉)品系CK595-1为材料,系统研究了对棉铃虫1~5龄幼虫存活及生长发育的影响。结果表明,Bt棉对棉铃虫的杀虫活性和体重抑制率有明显的器官和幼虫龄期间差异,其活性顺序为叶>蕾>铃>花,其作用随着幼虫龄期的增大而降低。棉铃虫1~4龄幼虫连续取食Bt棉叶片和棉蕾不能正常化蛹,5龄幼虫可部分化蛹及羽化;1~4龄幼虫取食Bt棉的花及2~5龄幼虫连续取食Bt棉铃后均可部分化蛹及羽化,化蛹率随龄期增大而增加。  相似文献   

11.
Zusammenfassung Verbände des ökologischen Landbaus wie z. B. Bioland, Gäa, Demeter; Naturland, Ernte für das Leben oder Bio Suisse beschränken ihre Mitglieder bei der Wahl von Vorratsschutzmaßnahmen. Vorrang besitzen Maßnahmen zur Vermeidung von Schädlingen gegenüber Bekämpfungsmaßnahmen. Fallen müssen zur Befallsüberwachung eingesetzt werden, um einen Befall durch Vorratsschädlinge frühzeitig zu erkennen. Diese Maßnahmen sollen den weitgehenden Verzicht auf chemisch-synthetische Mittel ermöglichen. In diesem Beitrag werden die Empfehlungen der Verbände mit den derzeit verfügbaren chemischen Mitteln für den Vorratsschutz abgeglichen. Erfahrung in der praktischen Umsetzung von physikalischen und biologischen Verfahren werden diskutiert und Defizite bei der Befallsüberwachung und Bekämpfung beschrieben.  相似文献   

12.
We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.  相似文献   

13.
Real-time PCR (TaqMan®) assays were developed for the specific detection and discrimination of Colletotrichum spp., C. acutatum and C. gloeosporioides causing anthracnose in strawberry using the most divergent area of the internal transcribed spacers (ITS1 and ITS2) and 5·8S ribosomal RNA (rRNA) gene region. The specificity of the new assays was tested using DNA from six species of Colletotrichum and nine fungal species commonly found associated with strawberry material, and additionally by comparing the sequences with those from databases using a blast search. The sequences only showed identity with homologous sequences from the desired target organisms. The new assays were 10–100 times more sensitive than conventional PCR methods previously published for the diagnosis of strawberry anthracnose. When real-time PCR was compared with ELISA methods, PCR improved the sensitivity of the identification by obtaining positive results for samples of strawberry plant material that tested negative with ELISA. The development of C. acutatum was monitored using artificially infected strawberry crowns from two strawberry cultivars (Camarosa and Ventana) and a real-time PCR assay specific for this species between January and June 2006. The amount of C. acutatum detected using real-time PCR varied significantly by month ( P  < 0·001), but not by cultivar ( P  = 0·394). The new assays were shown to be useful tools for rapid detection and identification of these pathogens and to allow rapid and accurate assessment of the casual agents of anthracnose in strawberry.  相似文献   

14.
《干旱区科学》2014,(6):782-782
正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad  相似文献   

15.
Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.  相似文献   

16.
Systematic information on the quantitative impact of Z ygogramma bicolorata on the biology of P arthenium hysterophorus is crucial as the seeds of this weed continue to germinate from the accumulated soil seed bank throughout the year in the form of different germinating flushes, while the activity of the beetle ceases during winter as it enters diapause. Therefore, plant–herbivore interactions need to be explored to develop predictions of the overall impact of the introduced beetle on the weed. The findings revealed that defoliation by Z . bicolorata had a significant impact on the plant height, density and flower production in flushes F 3, F 4 and F 5, but not in F 1 and F 2 that exhibited longer periodicity, profuse branching, a longer flowering period and maximum flower production and contributed mostly to the existing seed soil bank. Therefore, total depletion of the existing soil seed bank was not possible. Consequently, the effect of augmentative field releases of laboratory‐reared beetles was explored on F 1 and F 2 in February for three consecutive years (2011–2013). Before initiating the trial, random soil samples were taken from the plots that were assigned to the paired treatments (i.e. with the beetle and without the beetle [insecticide‐treated]) and it was found that the seed bank in those samples did not differ. The single release of Z . bicolorata adults at five per plant at the six‐leaf stage significantly reduced the soil seed bank, compared to without the biocontrol agent, irrespective of the flushes at the end of the season.  相似文献   

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The effects of the saprophytic mycoflora and its interference with cereal aphids on growth and yield of winter and spring wheat was studied in field experiments in 1980, 1981 and 1982.Yields varied between 5000 and 8000 kg dry matter of kernels per ha. The effect of the saprophytic mycoflora on yield was determined in different treatments: A) no control measures against cereal aphids and saprophytic and necrotrophic fungi, B) no control of cereal aphids, control of saprophytic and necrotrophic fungi, C) control of cereal aphids and control of saprophytic and necrotrophic fungi, D) control of cereal aphids and stimulation of saprophytic mycoflora and E) control of cereal aphids, no control of saprophytic and necrotrophic fungi nor stimulation of saprophytic mycoflora.Considerable differences in top densities of saprophytic mycoflora (10 times as large in A and D as in B and C) were determined. The consequences of these differences for the growth and productivity of wheat were minor. A negative effect of saprophytic mycoflora on the yield could not be detected in 1981 and 1982, whereas a small positive significant effect was found in 1980. This stimulation may have been due to competition between necrotrophic fungal pathogens and saprophytic mycoflora. As a result of favourable weather conditions necrotrophic fungal pathogens were very numerous in 1980 and could form an important yield reducing factor. Yield levels may effect the importance of the necrotrophic and saprophytic mycoflora as yield reducing factors. Additionally, in the presence of aphid honeydew captafol was found to be relatively ineffective against saprophytic fungi.  相似文献   

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