非昆虫源人工饲料对异色瓢虫生物学特性的影响

为明确一种非昆虫源人工饲料对异色瓢虫的饲养效果,以豌豆蚜为对照,研究了该人工饲料对异色瓢虫生长发育和生殖能力的影响。结果表明,取食人工饲料的异色瓢虫从卵到成虫的累计存活率达到82.2%,饲喂蚜虫的对照组为71.1%;与对照组相比,取食人工饲料的异色瓢虫幼虫总历期延长(人工饲料16.24 d,对照12.47 d),蛹重减轻(人工饲料27.74 mg,对照33.93 mg),成虫寿命延长(人工饲料雌虫103.6 d,雄虫82.9 d;对照雌虫85.7 d,雄虫77.1 d),10 d累计产卵23.5粒,约为对照组的5%,但人工饲料对异色瓢虫的羽化率和后代卵的孵化率无显著影响;幼虫期饲喂人工饲料、成虫期改喂蚜虫的异色瓢虫10 d产卵量352.1粒,约为对照组的80%。本研究所用人工饲料能提高异色瓢虫幼虫存活率和成虫寿命,且幼虫期取食人工饲料对成虫期产卵量影响较小,因此适于作为异色瓢虫人工饲养中幼虫阶段的食物。     

橘小实蝇洛阳种群对毒死蜱的敏感性研究

采用人工饲料混毒法,初步测定了毒死蜱、甲氧虫酰肼、螺虫乙酯、氟氯氰菊酯和噻虫胺对2日龄橘小实蝇洛阳种群成虫的毒力,并进一步研究了不同日龄橘小实蝇洛阳种群成虫对毒死蜱的敏感性。结果表明,处理48 h后,供试药剂中对橘小实蝇2日龄成虫毒力最高的是毒死蜱,其对雌成虫的LC_(50)为0.455 4μg/mL,对雄成虫的LC_(50)为0.300 8μg/mL;毒死蜱对15个不同日龄橘小实蝇雌成虫的LC_(50)为0.314 6~10.055 8μg/mL,对雄成虫的LC_(50)为0.222 7~5.840 7μg/mL,不同日龄间呈现出较大的敏感性差异,且雄成虫比雌成虫对毒死蜱更敏感。     

龙爪槐花对异色瓢虫成虫寿命的影响

本文研究了龙爪槐花和其所含的主要糖类对异色瓢虫成虫寿命的影响。室内用龙爪槐花饲养的异色瓢虫雌、雄成虫平均寿命分别为10.96和10.83 d,显著长于龙爪槐叶上成虫寿命(雌:3.98 d,雄:3.65 d);室外龙爪槐花序上生长的异色瓢虫成虫平均寿命(雌性:14.72 d,雄性:15.46 d)也显著高于枝条上的个体(雌:3.90 d,雄:3.82 d)。补充葡萄糖、果糖、蔗糖和麦芽糖4种糖液,能显著延长异色瓢虫成虫寿命。龙爪槐花含糖量较高的花粉与花蜜是异色瓢虫成虫的适宜食物、能维持其种群发生,是花期龙爪槐上虽没有蚜虫发生、但仍有高密度异色瓢虫成虫的主要原因。     

不同营养源对细点扁股小蜂寿命和产卵量的影响

采用单管饲养法,研究了不同营养源对细点扁股小蜂成虫寿命和产卵量的影响.结果表明:葡萄糖、蔗糖、蜂蜜饲养的雌蜂和雄蜂寿命差异显著(P＜0.05),而花粉、清水和对照饲养的雌蜂和雄蜂寿命差异不显著;补充蜂蜜、葡萄糖、蔗糖等营养均能显著延长细点扁股小蜂的寿命,与补充花粉、清水处理相比,平均寿命延长了3～9倍;20％蜂蜜饲养效果显著高于其他浓度,雌蜂寿命达到(35.2±1.1)d,较无饲喂处理寿命延长14倍以上;产卵量方面,10％和15％葡萄糖饲养效果显著高于其他浓度,雌蜂产卵量分别达到(67.5±3.4)粒和(65.6±2.7)粒,是清水饲喂处理的10倍以上.该研究结果可以为细点扁股小蜂的大量繁殖提供参考.     

外源营养补充对圆柏大痣小蜂成虫寿命的影响

为探究外源营养对圆柏大痣小蜂Megastigmus sabinae Xu et He成虫寿命的影响,本研究通过给当日羽化的同批次圆柏大痣小蜂成虫饲喂清水、蔗糖水及蜂蜜水,研究不同外源营养饲喂对雌、雄成虫寿命的影响。研究表明：3种喂养条件下雄蜂寿命均短于雌蜂,其中清水饲喂雌、雄蜂寿命差异显著;取食蔗糖水和蜂蜜水的圆柏大痣小蜂雌蜂寿命分别为18 d和14 d,两者均与饲喂清水对照之间存在显著差异;雌、雄蜂单独饲喂与雌、雄蜂混合饲喂存活数变化趋势基本一致。本研究为圆柏大痣小蜂生物防治研究提供虫源保障,同时也为研究圆柏大痣小蜂的生物学特点和行为提供支持。     

基于最大熵模型的沙棘绕实蝇适生性研究

沙棘绕实蝇(Rhagoletis batava Hering)是危害沙棘果实的重要害虫。本研究采用Maxent模型,在收集和整理沙棘绕实蝇全球地理分布信息的基础上,筛选出与该虫发生相关的11个关键环境变量,预测了当前及未来气候条件下该虫在全球以及我国的适生区和适生程度。在当前气候条件下,该虫在全球的适生范围主要集中在北温带地区,在我国的适生范围较广且适生程度较高;在2050年的两种气候情景下,沙棘绕实蝇在全球的适生区北界均向北移动,在我国的适生范围均略有扩大且适生区向西南部拓展。建议我国相关部门进一步加强针对沙棘绕实蝇的入侵防控工作。     

栎黄枯叶蛾对沙棘林的危害及生物学特性

栎黄枯叶蛾(Trabala vishnou gigantina Yang)是近年在沙棘林中大面积暴发的一种食叶害虫,以幼虫取食叶片,导致沙棘长势衰弱甚至死亡.本文采用野外调查和室内饲养观察相结合的方法对该虫的为害程度、形态特征、生活史、生物学特性等进行研究.结果表明:在陕西吴起,栎黄枯叶蛾为害严重,被害株率达到92.36％,枯死率达到6.45％,平均虫口密度为8.3头/株.该虫1年发生1代,以卵在茧表面、枝条及叶片等处越冬;翌年5月中下旬开始孵化,7月下旬开始结茧化蛹,蛹期平均(24.5±3.1)d;成虫始见于8月下旬,终见于9月下旬,羽化高峰期为9月上旬.成虫羽化主要集中在17:00-23:00,整个过程持续40～80 min;羽化后无需补充营养,至第2日方能交配产卵,交配时间为凌晨1:00-5:00,高峰期为3:00-4:00左右;雌虫只交配1次,雄虫可多次交配.成虫寿命为6～13 d.雌虫交尾后即可产卵,平均产卵量可达297粒.栎黄枯叶蛾生物学特性的系统研究,为其控制措施的制定提供了科学依据.     

补充外源营养对豌豆潜蝇姬小蜂寿命的影响

采用单管饲养法,研究了外源营养对豌豆潜蝇姬小蜂寿命的影响。结果表明:外源营养对不同性别豌豆潜蝇姬小蜂寿命的影响差异不显著。补充蜂蜜、葡萄糖、蔗糖、果糖等糖类营养均能显著延长姬小蜂的寿命,与补充牛血清白蛋白、清水以及无饲喂处理相比,平均寿命延长了5～9倍。15%葡萄糖水、15%蜂蜜水和15%蔗糖水的饲喂效果显著好于其他浓度,雌蜂平均寿命分别达(47.0±3.5)d、(45.7±2.9)d和(44.5±3.5)d,较无饲喂处理寿命延长15倍以上。该测定结果可以为豌豆潜蝇姬小蜂的大量繁殖提供一定参考。     

樟树重要食叶害虫——樟蚕生物学特性研究

樟树(Cinnamomum camphora)是我国南方重要的园林绿化树种和用材树种,但近年来遭受樟蚕(Eriogyna pyretorum)等害虫的持续为害。为此,采用野外调查和室内饲养相结合的方法 ,观察樟蚕生物学特性。结果表明,樟蚕在我国福州地区1年1代,以蛹越冬,世代历期平均338.08 d。其中,卵期32.57 d,幼虫期58.87 d,蛹期231.50 d,成虫期10.61 d。以幼虫为害当年新叶,1～3龄幼虫群集为害,4～7龄幼虫分散取食,6～7龄幼虫取食量最大。成虫于16时至20时羽化,喜夜间活动,寿命较长。雌虫的幼虫期为7龄,雄虫的幼虫期只有6龄,雌雄性比为1.73∶1。     

雌虫单头饲养对蠋蝽寿命和繁殖力的影响

本研究分别对有效交配后, 单头饲养和配对饲养的蠋蝽雌虫寿命和繁殖力参数进行统计分析?试验结果表明:有效交配后, 单头饲养的蠋蝽雌虫平均产卵量为343.80粒?平均产卵次数14.83次?平均寿命为53.13 d, 分别显著高于对照组(配对饲养)的平均产卵量(258.20粒)?平均产卵次数(10.63次)和平均寿命(45.30 d); 蠋蝽的单次产卵量?卵孵化率?卵直径均随产卵次数增加而减小, 其中单头饲养组的减小趋势显著; 单头饲养组蠋蝽的卵孵化率为59.58%, 显著低于对照组的68.89%, 而单头饲养组蠋蝽单雌所产卵的孵化数192.95头较对照组的177.87头更高?蠋蝽雌虫有效交配后进行单头饲养有利于延长蠋蝽寿命?提高其繁殖力?     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.     

Transgene herbizidresistente Kulturen

Zusammenfassung Herbizidresistente Kulturpflanzen nehmen unter den derzeit weltweit angebauten gentechnisch veränderten Ackerbaukulturen Sojabohne, Baumwolle, Raps und Mais den weit überwiegenden Anteil ein. Als Ursachen für die rasche Zunahme der Anbauflächen herbizidresistenter Sorten sind unter anderem die Unzulänglichkeiten der für diese Kulturen bestehenden Herbizidlösungen sowie die Zunahme der pfluglosen Bestellverfahren zu sehen. Im Gegenzug hat die Minimalbodenbearbeitung aufgrund der Einführung der Herbizidresistenztechnologie, insbesondere in Sojabohne, ein ausgeprägtes Flächenwachstum erfahren.Als Entscheidungskriterien für die Wahl des Unkrautbekämpfungssystems unter Einbezug des Anbaus herbizidresistenter oder konventioneller Sorten lassen sich aus den Erfahrungen der vergangenen 8 Jahre anführen: Sortenleistung, erhöhte Kulturverträglichkeit und zeitliche Anwendungsflexibilität, Wirkungssicherheit einer Nachauflaufbehandlung in Trockenregionen, Wirkungsbreite, Wirkungsdauer und Bekämpfung resistenter Unkrautbiotypen. Aufgrund fehlender Zulassungen und Kennzeichnungsvorschriften in wichtigen Exportmärkten sind für den Anbau transgener Sorten in Übersee auch Vermarktungseinschränkungen sowie für den Anbau in Europa Haftungs- und Koexistenzregeln wichtige einzelbetriebliche Entscheidungsparameter.Fortschritte erfährt die Herbizidresistenztechnologie kurz- und mittelfristig in der Weiterentwicklung bereits praktizierter Spritzfolgen und Tankmischungen zu Fertigformulierungen der Komplementärherbizide mit residualen Partnern. Zur Bekämpfung und Vorbeugung der Ausbreitung neuer herbizidresistenter Biotypen werden die Komplementärherbizide mit Partnern anderer Wirkungsmechanismen kombiniert. Weitere Entwicklungen sind die Kombination verschiedener transgener Merkmale mit der Herbizidresistenz sowie die Ausweitung von den derzeit dominierenden Kulturen auf weltweit weniger bedeutsame Kulturen, in denen die Entwicklung neuer konventioneller Herbizidwirkstoffe bisher wenig erfolgreich war oder im Verhältnis zum Aufwand nur bedingt attraktiv ist. Für die langfristige Entwicklung könnte die Plastidentransformation zur Verhinderung einer unerwünschten Ausbreitung transgener Merkmale Bedeutung erlangen.     

Pathogenic fungi involved in root rot of peas in the Netherlands and their physiological specialization

Research on root rot pathogens of peas in the Netherlands has confirmed the prevalence ofFusarium solani, F. oxysporum, Pythium spp.,Mycosphaerella pinodes andPhoma medicaginis var.pinodella. Aphanomyces euteiches andThielaviopsis basicola were identified for the first time as pea pathogens in the Netherlands. Other pathogens such asRhizoctonia solani andCylindrocarpon destructans were also found on diseased parts of roots. F. solani existed in different degrees of pathogenicity, and was sometimes highly specific to pea, dwarf bean of field bean, depending on the cropping history of the field.A. euteiches was specific to peas, whereasT. basicola showed some degree of physiological specialization.     

Surveys of cereal diseases and pests in the Netherlands. 3. Monographella nivalis and Fusarium spp. in winter wheat fields and seed lots

Data from surveys of winter wheat fields in the period 1974–1986 and of seed lots in the period 1962–1986 and identifications of diseases on plant samples were compiled to describe the occurrence of snow mould (Monographella nivalis) andFusarium spp. On average,M. nivalis dominated overFusarium spp. The complex ofFusarium spp. constituted mainly ofF. culmorum, followed byF. avenaceum andF. graminearum. M. nivalis was dominant in May on stem-bases and in July on leaves and leaf sheaths. On seedsM. nivalis predominated only in years with low temperatures in July and August.Average brown footrot infection in the field was 4% tillers in May and 5% culms in July. Brown footrot intensity in July was high in cropping seasons with high precipitation in October and with low temperatures in October, November and December. In July during the early eighties, an average of 8% of leaves and 6% of flag leaf sheaths were infected byM. nivalis. Average ear blight incidence was 1.2% glumes infected. Seed contamination by these pathogens averaged 16% in the years 1962–1986. The contamination was high in years with high precipitation in June, July and August. Aspects of cv. resistance and yield loss are illustrated.