丁烯氟虫腈对小菜蛾的生物活性及田间防治效果

为系统地评价新药剂丁烯氟虫腈对小菜蛾的生物活性及环境因素对其应用效能的影响,在室内,建立了丁烯氟虫腈对小菜蛾幼虫的敏感毒力基线,测定了丁烯氟虫腈对小菜蛾卵的活性,测定了温度、龄期对其生物活性的影响以及对小菜蛾3龄幼虫的持效性,并进行了田间防治试验。结果表明,丁烯氟虫腈对小菜蛾具有较高的触杀毒力,48hLD50为0.45μg/头。用64mg/L丁烯氟虫腈药液浸渍,对小菜蛾卵的孵化抑制率为46.24%,且初孵幼虫存活率明显降低;丁烯氟虫腈对小菜蛾1～2龄幼虫的毒力较高,3龄以后随虫龄增大,敏感性降低;温度对丁烯氟虫腈毒力发挥有显著影响,表现明显的正温度系数效应,温度从15℃上升到32℃,毒力增强15.49倍。持效性试验表明,64mg/L丁烯氟虫腈对小菜蛾3龄幼虫的校正死亡率在84%～95%之间,持效15天以上。田间试验结果表明,丁烯氟虫腈对小菜蛾具有较好防治效果,以5%丁烯氟虫腈乳油1200倍液施药,药后1天防效达76%以上,药后7天在88%以上,与相同用量的同类药剂氟虫腈无差异显著性。     

茶毛虫核型多角体病毒Bt混剂的作用特性

用生物测定的方法,研究了茶毛虫核型多角体病毒(EpNPV)与苏云金杆菌(Bt)配制而成的茶毛虫核型多角体病毒Bt混剂(EpNPV-Bt)的增效作用、速效作用、拒食作用和兼治作用。结果表明,在16～28℃温度范围内,EpNPV-Bt对茶毛虫的作用在整个死亡周期表现为相加作用,协同毒力指数主要分布在-20%～20%之间,其中16、19、28℃的死亡前期表现为增效作用,协同毒力指数大于20%,22℃的死亡中期表现为拮抗作用,协同毒力指数小于-20%。EpNPV-Bt对茶毛虫LT30为5.6天,比EpNPV减少3.8天,幼虫的死亡速度提高了1.8倍。EpNPV-Bt对茶毛虫的拒食效果明显,取食量比EpNPV减少66.2%。EpNPV-Bt对茶刺蛾、用克尺蠖和茶尺蠖等茶树害虫具有兼治作用,其中对茶刺蛾的死亡率达85.8%。     

新化合物HNPC-A8008对鳞翅目害虫的作用方式和作用特性

为系统评价新型吡唑类杀虫剂HNPC-A8008对鳞翅目害虫的生物活性、作用方式及环境因素对其应用效能的影响,通过叶片夹毒法、点滴法和根部内吸法测定了其胃毒活性、触杀活性和内吸活性,采用Potter喷雾法测定了温度、龄期对其生物活性的影响及对3龄粘虫幼虫的持效性,并应用浸渍法测定了其对粘虫卵的活性。结果表明,HNPC-A8008对粘虫表现出很好的胃毒毒力,且具有一定的触杀活性,但内吸活性较弱,药后24 h和72 h对粘虫触杀LD50和胃毒毒力LC50值分别为221.38μg/头和0.73 mg/L;2 000 mg/L浓度下,粘虫的内吸死亡率为56.67%;对1~4龄粘虫幼虫的的毒力分别为5.33、12.21、32.05和39.60 mg/L,对4龄的毒力最低;400 mg/L药液对粘虫卵的孵化抑制率为88.00%,初孵幼虫的死亡率为61.93%。温度对HNPC-A8008毒力发挥有显著影响,从15℃升至35℃,毒力增强了3.47倍,属正温度系数类杀虫剂。HNPC-A8008具有较长的持效期,药后0~14 d对3龄粘虫的LC50值在30.55~48.35 mg/L之间。     

多杀霉素和甲氨基阿维菌素苯甲酸盐对小菜蛾的室内生测及田间药效评价

分别采用触杀毒力法和摄食毒力法测定了多杀霉素和甲氨基阿维菌素苯甲酸盐对小菜蛾的室内生物活性,研究结果表明：药后48h,甲维盐的触杀活性和胃毒活性均好于多杀霉素。另外,2种药剂的胃毒活性均好于触杀活性。田间药效试验结果表明,多杀霉素2.5%悬浮剂对小菜蛾幼虫表现出优良的防治效果。在小菜蛾发生期,以15.00～19.99ga.i./hm2兑水均匀喷雾,施药后7d,防治效果可达90%以上。用甲氨基阿维菌素苯甲酸盐2%乳油（对照药剂）常规使用剂量喷雾,最高防治效果达85%以上,稍逊于多杀霉素2.5%悬浮剂。     

土壤温、湿度对两种微胶囊杀虫剂毒力的影响

以华北大黑鳃金龟幼虫为生测对象,在常规毒力测定的基础上研究土壤温、湿度对35%辛硫磷和30%毒死蜱微囊悬浮剂毒力的影响。结果显示:35%辛硫磷微囊悬浮剂对华北大黑鳃金龟幼虫的毒力高于30%毒死蜱微囊悬浮剂,约是其毒力的3～9倍;在试验湿度和温度范围内,35%辛硫磷和30%毒死蜱微囊悬浮剂对供试幼虫的杀虫效果随着温度的升高而逐渐增强;在相同温度条件下,2种微囊制剂在含水量为10%的土壤中杀虫效果高于含水量20%的土壤。     

温度对白面叉草蛉发育与繁殖的影响

白面叉草蛉Dichochrysa albofrontata Yang et Yang是螺旋粉虱Aleurodicus dispersus RusseⅡ的重要捕食性天敌。本文在实验室温(26℃～32℃)及特设(16℃、20℃、24℃、28℃、32℃)下对白面叉草蛉的发育及繁殖情况进行了研究。结果表明:白面叉草蛉发育经历卵、幼虫、蛹及成虫四个阶段,幼虫期分3个龄期。幼虫捕食螺旋粉虱的卵、若虫和拟蛹,偏嗜拟蛹,其中3龄幼虫捕食量大。在室温下,完成一个世代的时间为31.5d～41.5d,其中幼虫期平均14.3d,蛹期平均8.7d,卵期平均3.3d。在16℃～32℃温度范围内,白面叉草蛉均可完成世代发育,各虫态的发育历期随温度升高而缩短,其中在32℃下最短,分别为卵3.1d、1龄幼虫4.2d、2龄幼虫4.0d、3龄幼虫5.2d、蛹10.8d。各虫态的发育起点温度分别为卵11.8℃、幼虫7.5℃、蛹9.5℃、世代10.5℃,卵、幼虫、蛹和世代完成发育所需的有效积温分别为62.7日度、310.5日度、230.7日度、716.1日度。据此估算,该虫在海南每年可完成6～7代。在16℃～32℃范围内各虫态及世代存活率随温度升高而...     

温度对椰甲截脉姬小蜂功能反应的影响

在162、02、42、83、2℃5个温度梯度下,测定了椰甲截脉姬小蜂对椰心叶甲的寄生情况。结果表明:在试验温度范围内各温度的功能反应数据均能用Holling圆盘方程很好地拟合;瞬时攻击率在一定范围内随温度的升高而增大,28℃时达到最高值,32℃显著下降;在16~32℃范围内,温度对处理时间影响较小;各温度下在供寄主的24h内,均有部分雌蜂并不产卵寄生于椰心叶甲幼虫,产卵寄生的雌蜂百分率随寄主密度增加而增加。     

温度对稻茎毛眼水蝇实验种群增长的影响

试验结果表明:在17～31℃恒温范围内,稻茎毛眼水蝇的发育速率随温度上升呈逻辑斯蒂曲线趋势。幼虫、蛹存活率、成虫产卵量、种群增长指数随温度的上升呈抛物线趋势。卵孵化率在20～31℃范围内无显著差异,均在92％以上。在17℃和35℃时,孵化率下降至86.67％和76.36％。在35℃时,幼虫不能存活,成虫不产卵。     

双七瓢虫发育起点温度与有效积温研究

在19、22、25、28、31℃恒温条件下,对双七瓢虫[Coccinula quatuordecimpustulata(Linnaeus)]各虫态的发育历期、发育速率、发育起点温度和有效积温进行了研究.结果表明,在19-31℃温度范围内,双七瓢虫各虫态发育速率加快、发育历期随着温度的升高逐渐缩短,在19、22、25、28、31℃温度条件下,卵-蛹期的发育历期分别为32.13、21.59、17.81、13.16 d和11.18 d.试验测得其卵,1～4龄幼虫和蛹的发育起点温度分别为11.47、12.15、12.74、15.02、12.96℃和13.09℃,相应的有效积温分别为39.16、34.06、22.89、21.36、39.93℃和42.41℃.根据有效积温和发育起点温度建立了回归方程和历期预测式.     

甲维盐·辛磷混配对小菜蛾的毒力分析

以小菜蛾(Plutella xylostella L)3龄幼虫为试虫测定了甲维盐、辛硫磷及两者5种不同配比的混配剂的毒力.甲维盐与辛硫磷混配后增效显著,在5种配比中以甲维盐:辛硫磷=1:100为最佳配比,共毒系数为154.31.与单剂相比,该配比明显提高杀虫率.     

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.     

Diagnostics,genetic diversity and pathogenic variation of ascochyta blight of cool season food and feed legumes

Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However, where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas. Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within populations is important in the selection of resistant genotypes.     

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.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

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.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

Brief Guide for Authors

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     

The use of Solacol® (validamycin) as a growth retardant in the isolation of soil fungi

Solacol^®, a formulation of the antibiotic validamycin, at 0.33% in 2% malt extract agar, reduced the spread of fungi on dilution plates drastically and allowed twice as much incubation time before subculturing; this resulted in an elevated number of species isolated. Using pure cultures of 62 common soil fungi, it was shown that all fast-growing species (exceptPythium ultimum) were efficiently inhibited but not completely suppressed. Inhibition was comparable to that by 0.5% oxgall, though, while this substance completely suppressed several species, Solacol very strongly inhibited onlyGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum andRhizoctonia solani. In a further experiment each separate constituent of Solacol was tested against 22 fungi at equivalent concentrations. Validamycin strongly inhibitedChaetomium globosum and two Basidiomycetes, though hardly more than the non-ionic detergent which mainly inhibited the other fungi. A few species were, however, more inhibited by Solacol than by the detergent alone. Solacol at 0.33% is a suitable aid in dilution plating of soil fungi, by increasing the number of colonies and species observed.Samenvatting Solacol^®, een formulering van het antibioticum validamycine, remde de groei van schimmels in verdunningsplaten met een concentratie van 0.33% in 2% moutagar en maakte het mogelijk de periode tot afenten met een factor 2 te verlengen; daardoor was het aantal geïsoleerde soorten duidelijk toegenomen. Met reincultures van 62 algemene grondschimmelsoorten werd aangetoond, dat alle snelgroeiende soorten (met uitzondering vanPythium ultimum) voldoende geremd, maar niet volkomen onderdrukt werden. Het remmingspercentage was vergelijkbaar met dat van 0.5% ossegal, hoewel dit laatste sommige soorten volkomen onderdrukte; Solacol remde alleenGaeumannomyces graminis, Gerlachia nivalis, Harzia acremonioides, Verticillium biguttatum enRhizoctonia solani zeer sterk. In een volgend experiment werden de componenten van Solacol t.o.v. 22 fungi apart getoetst in concentraties equivalent aan 0.33% Solacol. Validamycine remde alleenChaetomium globosum en twee basidiomyceten behoorlijk, maar nauwelijks meer dan de niet-ionische uitvloeier, die in hoofdzaak de overige remeffecten veroorzaakte. Enkele soorten werden echter door het complete Solacol veel sterker geremd dan door de uitvloeier alleen. Solacol in een verdunning van 0,33% wordt aanbevolen bij verdunningsplaten voor het isoleren van grondschimmels ten einde het aantal kolonies en soorten te verhogen.     

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.