Stage-specific mortality of Rhagoletis indifferens (Diptera: Tephritidae) exposed to three species of Steinernema nematodes

Mortality of larval, pupal, and adult western cherry fruit fly, Rhagoletis indifferens (Tephritidae) exposed to the steinernematid nematodes Steinernema carpocapsae, Steinernema feltiae, and Steinernema intermedium, was determined in the laboratory and field. Larvae were the most susceptible stage, with mortality in the three nematode treatments ranging from 62 to 100%. S. carpocapsae and S. feltiae were equally effective against larvae at both 50 and 100 infective juveniles (IJs)/cm². S. intermedium was slightly less effective against larvae than the other two species. Mortalities of R. indifferens larvae at 0, 2, 4, and 6 days following their introduction into soil previously treated with S. carpocapsae and S. feltiae at 50 IJs/cm² were 78.6, 92.5, 95.0, and 77.5% and 87.5, 52.5, 92.5, and 70.0%, respectively, and at 100 IJs/cm² were 90.0, 92.0, 100.0, and 84.0% and 90.0, 50.0, 42.0, and 40.0%, respectively. There was no decline in mortality caused by S. carpocapsae as time progressed, whereas there was in one test with S. feltiae. Larval mortalities caused by the two species were the same in a 1:1:1 vermiculite:peat moss:sand soil mix and a more compact silt loam soil. In the field, S. carpocapsae and S. feltiae were equally effective against larvae. Pupae were not infected, but adult flies were infected by all three nematode species in the laboratory. S. carpocapsae was the most effective species at a concentration of 100 IJs/cm² and infected 11–53% of adults that emerged. The high pathogenicity of S. carpocapsae and S. feltiae against R. indifferens larvae and their persistence in soil as well as efficacy in different soil types indicate both nematodes hold promise as effective biological control agents of flies in isolated and abandoned lots or in yards of homeowners.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

两种国兰C类花发育MADS基因的克隆与表达研究

该研究以蕙兰(Cymbidium faberi)和墨兰(Cymbidium sinense)为材料,利用RT-PCR对AGAMOUS (AG)基因进行克隆,并利用qRT-PCR进行组织表达.结果 表明:(1)获得3个AG基因均属于植物特有的C类MIKC型MADS-box基因,其中2个蕙兰AG基因命名为CfAG1(登录号...     

Coinoculation of aseptically grown Douglas fir with pairs of ectomycorrhizal fungi

Douglas fir seedlings grown under aseptic conditions in a peat-vermiculite substrate were inoculated with four pairs of ectomycorrhizal fungi to assess the relative inoculum dosages needed to establish two mycorrhizal fungi simultaneously in the same root system. The dual fungal combinations tested were: Pisolithus arhizus + Rhizopogon subareolatus, P. arhizus + R. roseolus, Laccaria bicolor + P. arhizus and L. bicolor + R. subareolatus. A total of 12 ml of inocula per plant was applied at the rates: 0+12, 3+9, 6+6, 9+3, 12+0, and 0+0 (v+v) for each combination. After 3 months growth, the number of mycorrhizas and uninfected short roots as well as the total plant biomass produced were recorded. Inoculations were successful with the fungal combinations P. arhizus + R. subareolatus and L. bicolor + P. arhizus. Plants developed P. arhizus and R. subareolatus mycorrhizas only at the rate 9Pa + 3Rs; at other rates tested, only monospecific mycorrhizas were formed. Plants developed L. bicolor and P. arhizus mycorrhizas at the three rates containing both fungi. L. bicolor behaved as an aggressive root colonizer and its level of root colonization remained constant at increasing rates of P. arhizus inoculum. L. bicolor displaced R. subareolatus at all inocula rates. P. arhizus displaced R. roseolus except at the rate 3Pa + 9Rr, with only a low number of mycorrhizas formed by either fungus. Total plant biomass was significantly increased by the presence of any fungal combination up to four times the values for uninoculated controls. P. arhizus and R. subareolatus were more effective in promoting plant growth and stimulating short root formation than either L. bicolor or R. roseolus.     

Identification of novel sex pheromone components from a tussock moth, Euproctis pulverea

Two EAG-active compounds were found in the solvent extract of abdominal tips of virgin females of the tussock moth Euproctis pulverea (Leech) (Lepidoptera: Lymantriidae), and identified as (Z,Z,Z)-11,14,17-icosatrienyl isobutyrate and (Z,Z,Z)-11,14,17-icosatrienyl 4-methylvalerate at 190 and 80 ng female^–1, respectively, by means of GC-MS analyses and chemical derivatization. Esters of n-butyric acid, n-valeric acid, n-hexanoic acid and a methylheptanoic acid were also found at 3, 2, 0.4 and 9 ng female^–1 as minor EAG-inactive compounds. Two active compounds were also detected in the hexane extract of female anal tufts at 17 and 6 ng female^–1, respectively. In Okinawa, the binary blend of the synthetic compounds attracted male moths to the sticky traps, but single compounds did not. The significance of these findings in relation to parasitism by Telenomus euproctidis (Hymenoptera: Scelionidae) is discussed.     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Improving the biological control of Botryodiplodia disease on some Annona cultivars using single or multi-bioagents in Egypt

Botryodiplodia disease caused by Botryodiplodia theobromae is a recently disease of some Annona cultivars in Egypt, particularly in Behera Governorate, characterized by stem purple lesions, dieback, flowers, and fruits dry and soft rot. Six fungal and bacterial bioagents, i.e., Trichoderma koningii, Trichoderma hamatum, Pseudomonas fluorescens, Pseudomonas putida, Tilletiopsis minor, and Tilletiopsis washingtonensis were tested either solely or at different amalgamations against Botryodiplodia disease, as foliar spraying using three Annona cultivars, i.e., Balady and Abd El-Razik (Annona squamosa) and Hindy (Annona cherimola). In vitro, studies revealed a significant inhibition towards the conidial germination of B. theobromae as well as on the disease incidence on artificially inoculated branches and fruits in the presence of the aforementioned bioagents. An unmistakable reduction in the disease was conspicuous under the action of multi-bioagent conduct. The bioagents were tested during 2003 and 2004 agricultural seasons under the field conditions at Nobaria, (Behera Governorate). A single application and all possible mixture of two or three of the bioagents were applied at 15 days intervals as a foliar spray. Botryodiplodia disease severity and sporulation of the pathogen were always reduced, when the multi-bioagents were applied. When Trichoderma spp. and Pseudomonads spp. were blended together, the disease was greatly abridged in the three tested cultivars compared to any of the sole bioagents. The multi-bioagents were more effective than any sole or even double treatments. The application of multi-bioagents also resulted in a significant increase of fruit yield.     

Removal of wastewater pathogen indicators in a constructed wetland in Leon, Spain

This paper studies the seasonal presence and removal of the pathogenous micro-organisms Escherichia coli, total coliforms (TC), Clostridium perfringens (Cp), faecal streptococci (FS), Giardia cysts, Cryptosporidium oocysts and helminth eggs, in a constructed wetland treatment system. The removal efficiency of this system with respect to the indicator micro-organisms achieved maximum values in spring and autumn at 99.9% for E. coli and TC, respectively, in winter at 97.0% for FS, in summer at 100% for Clostridium and throughout the year, also at 100%, in the case of Giardia cysts, Cryptosporidium oocysts and helminth eggs. In general, very low protozoan and helminth egg counts were found, and the system demonstrated efficient reduction of the wastewater indicator pathogens.     

Constant association of ophiostomatoid fungi with the bark beetle <Emphasis Type="Italic">Ips subelongatus</Emphasis> invading Japanese larch logs

Ceratocystiopsis, Ceratocystis, Grosmannia, and Ophiostoma species were isolated from Ips subelongatus and beetle-infested Japanese larch logs collected at several areas in central and northern Honshu Island, Japan, to determine constant associates of I. subelongatus. Ceratocystiopsis minuta, two species of Ceratocystis, three species of Grosmannia, and four species of Ophiostoma were isolated. Of the fungi isolated in the present study, G. laricis, O. brunneociliatum, and O. piceae were constant associates of the beetles. Ceratocystis fujiensis, Ceratocystiopsis minuta, and Ophiostoma sp. F were occasionally isolated with high frequencies of occurrence but were not consistent associates. Ceratocystis fujiensis was most often isolated as the leading fungal invasion in the sapwood of Japanese larch logs invaded by I. subelongatus, confirming that the fungus acts as a primary invader of sapwood in beetle-attacked logs. Contribution No. 221, Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba     

An Evaluation of the Rust FungusGymnoconia nitensas a Potential Biological Control Agent for AlienRubusSpecies in Hawaii

The rust fungusGymnoconia nitensinfects blackberry (Rubus argutus) systemically in regions of the continental United States, producing bright yellow–orange masses of spores on newly developing floricanes during springtime. In tests to determine the suitability of this rust as a biological control agent forR. penetransin Hawaii, a species now thought to be conspecific withR. argutus,rooted cuttings of the Hawaiian plants were grown at North Carolina State University, inoculated, and observed. Other introduced weedyRubusspp. in Hawaii, includingR. ellipticus, R. rosifolius,andR. glaucus,as well as the two endemic speciesR. hawaiensisandR. macraei,also were inoculated. No species ofRubusare of commercial importance in Hawaii, but the protection of the native species, of whichR. macraeiis rare, was of utmost concern. The native Hawaiian species did not survive well in North Carolina in this study, however. Later availability of a plant pathogen containment laboratory in Hawaii enabled similar tests to be conducted at that facility. In addition to the above species,R. spectabilis(salmonberry), a species native to the Pacific Northwest with which the HawaiianRubusspp. are thought to share a common ancestor, was inoculated in Hawaii. Infection withG. nitensunder natural field conditions becomes apparent only when sporulation occurs on floricanes the second year following infection. However, experimental inoculation led to early responses of chlorotic leaf flecking and puckering, leaf and stem contortion, and stem gall formation, indicating the sensitivity ofR. penetrans(=R. argutus),R. hawaiensis,andR. macraeito this rust. Apparent systemic infection also resulted in sporulation on one plant ofR. macraei.Ability to attack the endemic species suggests thatG. nitenswould not be suitable for release in Hawaii as a biological control agent, at least on the islands with populations of the native species.     

Characterization of 14 novel microsatellite loci in the endangered <Emphasis Type="Italic">Liriodendron chinense</Emphasis> (Magnoliaceae) and cross-species amplification in closely related taxa

Fourteen polymorphic microsatellite loci were isolated and characterized from an AC-enriched genomic library of Liriodendron chinense (Magnoliaceae). The average allele number of these microsatellites was 5.2 per locus, ranging from three to eight. The observed and expected heterozygosity at population level were 0.07–1.00 and 0.10–0.83, respectively. These sets of microsatellites will be useful for studies of population genetic structure of L. chinense and L. tulipifera as well as to estimate fine-scale gene flow rates.     

Dominant mutant alleles of yeast protein kinase geneCDC15 suppress thelte1 defect in termination of M phase and genetically interact withCDC14

LTE1 encodes a homolog of GDP-GTP exchange factors for the Ras superfamily and is required at low temperatures for cell cycle progression at the stage of the termination of M phase inSaccharomyces cerevisiae. We isolated extragenic suppressors which suppress the cold sensitivity oflte1 cells and confer a temperature-sensitive phenotype on cells. Cells mutant for the suppressor alone were arrested at telophase at non-permissive temperatures and the terminal phenotype was almost identical to that oflte1 cells at non-permissive temperatures. Genetic analysis revealed that the suppressor is allelic toCDC15, which encodes a protein kinase. Thecdc15 mutations thus isolated were recessive with regard to the temperature-sensitive phenotype and were dominant with respect to suppression oflte1. We isolatedCDC14 as a low-copy-number suppressor ofcdc15-rlt1.CDC14 encodes a phosphotyrosine phosphatase (PTPase) and is essential for termination of M phase. An extra copy ofCDC14 suppressed the temperature sensitivity ofcdc15-rlt1 cells, but not that ofcdc15-1 cells. In addition, some residues that are essential for the Cdc14 PTPase activity were found to be non-essential for the suppression. These results strongly indicate that Cdc14 possesses dual functions; PTPase activity is needed for one function but not for the other. We postulate that the cooperative action of Cdc14 and Cdc15 plays an essential role in the termination of M phase.     

Effects of relative humidity on development, fecundity and survival of three storage mites

The developmental rate of immature stages and the reproduction of adults of Tyrophagus putrescentiae (Schrank), T. neiswanderi Johnston and Bruce and Acarus farris (Oudemans) were examined at 70, 80 and 90% r.h. and a constant temperature of 25°C. At 70% r.h., T. putrescentiae and A. farris immature stages failed to reach the protonymph stage as 100% of the larvae died, whereas T. neiswanderi was able to complete development. The developmental time of all immature stages for the three species was significantly increased as relative humidity was reduced. The mobile stages were particularly susceptible, as the time needed to complete their development at lower relative humidities suffered greater increases than the egg stage. At 70% r.h., T. putrescentiae and A. farris were not able to lay eggs and only 24% of T. neiswanderi pairs were fertile. The reproductive parameters of the three species at the relative humidities at which they were able to lay eggs showed significant differences, except for the percentage of fertile mating at 80 and 90% r.h. As relative humidity increased, preoviposition period was reduced and fecundity and daily fecundity was increased, whereas the oviposition period showed different patterns for the three species. The intrinsic rate of increase (r _m ) of T. neiswanderi at 70% r.h. was negative indicating that, at these conditions, mite populations of this species will diminish until they disappear. As relative humidity increased from 80 to 90% r.h. this parameter was almost twofold for both Tyrophagus species. The r _m obtained for A. farris at 90% r.h. was similar to that of T. neiswanderi at the same humidity while at 80% r.h. it was very small so that the population doubling time was more than 84 days. The influence of relative humidity on biology of these mites and its practical application as control measure are discussed.     

Activity of pupal parasitoids of the stable fly Stomoxys calcitrans and prevalence of entomopathogenic fungi in the stable fly and the house fly Musca domestica in Denmark

A survey was conducted on confined dairy cattle farms and a pig farm from May–October in 1999 to determine the activity and relative abundance of pupal parasitoids and the prevalence of entomopathogenic fungi in populations of the haematophagous stable fly, Stomoxys calcitrans (Diptera: Muscidae), in Denmark. Four species of pteromalids were found with Spalangia cameroni as the predominant. The other parasitoids were S. nigripes, S. nigra and Phygadeuon fumator (Ichneumonidae). Peak activity of the parasitoids was observed to be late in the summer and the beginning of autumn (August–September) when approximately 10% of the collected stable fly pupae were parasitised. Adult stable flies were infected with four species of entomopathogenic fungi: Entomophthora muscae, E. schizophorae, Beauveria bassiana and Verticillium lecanii. All fungi occurred in low percentages (max. 4%) and remained at this level throughout the sampling period. Likewise, adult house flies were infected with B. bassiana and V. lecanii,but Metarhizium anisopliae, Paecilomyces fumosoroseus and V. fusisporum were also recorded. The overall hyphomycete prevalence in house flies was 0.3%, and single species rarely exceeded 0.1%. The prevalence remained low in spite of increasing house fly numbers in August–September.     

Parasitoid-induced mortality of house fly pupae by Pteromalid wasps in the laboratory

House fly, Musca domestica L., pupae were exposed to six species of pteromalid parasitoids, Muscidifurax zaraptor Kogan and Legner, M. raptor Girault and Sanders, M. raptorellus Kogan and Legner, Pachycrepoideus vindemiae (Rondani), Spalangia nigroaenea Curtis, and Urolepis rufipes Ashmead. Exposures were made for 48 h at six parasitoid-to-host ratios to measure the effect of parasitoid density on parasitoid-induced mortality (PIM) of hosts (excluding mortality as measured by parasitoid emergence). PIM was evident at all parasitoid-to-host ratios for all six species. Fly eclosion declined with a corresponding increase in the parasitoid-to-host ratio; the reverse was generally true for PIM. Parasitoid emergence increased initially with a corresponding increase in the parasitoid-to-host ratio to a point (depending on the parasitoid species), but then declined. The three Muscidifurax spp. and P. vindemiae exhibited similar behavior and generally avoided previously stung hosts until ovipositional restraints broke down at the higher parasitoid-to-host ratios. S. nigroaenea and U. rufipes exhibited little ovipositional restraint, resulting in a high proportion of PIM of hosts. Understanding factors that influence PIM will provide better evaluations of field releases of parasitoids to control flies and will aid in the development of the most economic procedures for large scale rearing of pteromalid parasitoids.     

<Emphasis Type="Italic">HLA-A</Emphasis> allele associations with viral <Emphasis Type="Italic">MER9-LTR</Emphasis> nucleotide sequences at two distinct loci within the <Emphasis Type="Italic">MHC alpha</Emphasis> block

The study of the association of the Human Leukocyte Antigen (HLA) alleles and polymorphic retrotransposons such as Alu, HERV, and LTR at various loci within the Major Histocompatibility Complex allows for a better identification and stratification of disease associations and the origins of HLA haplotypes in different populations. This paper provides sequence and association data on two structurally polymorphic MER9-LTR retrotransposons that are located 54 kb apart and in close proximity to the multiallelic HLA-A gene involved in the regulation of the human immune system. Direct DNA sequencing and analysis of the PCR products identified DNA nucleotide variations between the MER9-LTR sequences at the two loci and their associations with HLA-A alleles as potential haplotype and evolutionary markers. All MER9-LTR sequences were haplotypic when associated with common HLA-A alleles. The number of SNP loci was 2.5 times greater for the solo LTR at the AK locus, which is located closer to the HLA-A gene than the solo or 3′ LTR at the HG locus. Our study shows that the nucleotide variations of the MER9-LTR DNA sequences are additional informative markers in fine mapping HLA-A genomic haplotypes for future population, evolutionary, and disease studies.     

10种棘豆属植物的trnL-F序列及其分子系统学研究

选择内蒙古27个样地采集的10种棘豆属植物54个单株,提取样品的基因组DNA,对其叶绿体trnL-F序列进行扩增、测序,所得序列利用ClustalX软件进行对位排列,并用MEGA5.0软件采用最大似然法构建系统发育树,以探讨棘豆属的种间关系与系统进化.结果显示:(1)10种棘豆属trnL-F的变异位点54个,信息位点46个,种间碱基差异百分率为1.9％,GC含量变化范围在30.69％～31.50％之间.(2)棘豆属与黄芪属各为一支,自展支持率达99％,支持棘豆属植物为单系起源.(3)系统树中小花棘豆的样本自成一支,为相对独立进化;多叶棘豆、砂珍棘豆和黄毛棘豆的样本相互混杂,表明亲缘关系很近,从而支持《内蒙古植物志》将三者归入真棘豆亚属轮叶棘豆组的观点.(4)刺叶柄棘豆的样本不同样地形成2个分支,对其亚属水平上的分类需进一步探讨.(5)缘毛棘豆与阴山棘豆的样本聚成一支,支持将二者归入矮生棘豆组.研究表明,trnL-F序列可为棘豆属下种间系统发育关系研究提供分子证据.     

Ribotyping of 16S and 23S rRNA genes and organization of rrn operons in members of the bacterial genera Gemmata,Planctomyces, Thermotoga,Thermus, and Verrucomicrobium

The number of organization of rrn genes of two members of the order Planctomycetales, Planctomyces limnophilus and Gemmata obscuriglobus, as well as three species from other bacterial phyla, namely Thermotoga maritima, Thermus aquaticus and Verrucomicrobium spinosum were examined by Southern blot hybridization analysis of restricted DNA with labeled 16S- and 23S rRNAs. Ribotyping analysis revealed that two species contain unlinked 16S- and 23S rRNA genes. Planctomyces limnophilus possessed two unlinked rrn genes which were separated from each other by at least 4.3 kb, and Thermus aquaticus had to unlinked 16S and 23S rRNA genes, separated from each other by at least 2.5 kb. Gemmata obscuriglobus exhibited five genes for which the organization could as yet not be determined because of the complex hybridization patterns. In the other two species, rrn genes clustered in operons. Thermotoga maritima had a single gene for each rRNA species which were separated by not more than 1.5 kb, while Verrucomicrobium spinosum had four copies of probably linked 16S and 23S rRNA genes with a maximal distance between 16S and 23S rRNA genes of 1.3 kb.     

瓜实蝇2种蛹寄生蜂生防潜能比较

[目的] 比较研究蝇蛹俑小蜂与蝇蛹金小蜂对瓜实蝇的控制潜能。[方法] 采用非选择性实验测定蝇蛹俑小蜂与蝇蛹金小蜂对瓜实蝇蛹的寄生效能、繁殖能力,并研究覆土厚度对2种寄生蜂寄生效能的影响。[结果] 2种寄生蜂对瓜实蝇的寄生率无显著性差异,但蝇蛹金小蜂的平均单雌产后代数比蝇蛹俑小蜂的多,分别为30和23头。土壤厚度显著影响2种寄生蜂的寄生效能,随着土壤厚度的增加,2种寄生蜂对瓜实蝇蛹的寄生率均显著下降,但蝇蛹金小蜂的寄生率下降更为迅速;蝇蛹俑小蜂最深可寄生8 cm土壤下的瓜实蝇蛹,而蝇蛹金小蜂在土壤厚度达到3 cm时就不能完成寄生。[结论] 蝇蛹俑小蜂较蝇蛹金小蜂更适合应用于瓜实蝇蛹的生物防治。