Novel Micro-organisms controlling plant pathogens

NARCIS (Netherlands)

Köhl, J.

2010-01-01

The invention relates to control of pathogen caused diseases on leaves, fruits and ears in plants, such as apple scab (Venturia inaequalis by treatment of plant with an isolate of Cladosporium cladosporioides. The treatment is effective in both prevention and treatment of the fungal infection

Cloning and functional characterization of the Rvi15 (Vr2) gene for apple scab resistance

NARCIS (Netherlands)

Schouten, H.J.; Brinkhuis, J.; Burgh, van der S.; Schaart, J.; Groenwold, R.; Broggini, G.A.L.; Gessler, C.

2014-01-01

Apple scab, caused by Venturia inaequalis, is a serious disease of apple. Previously, the scab resistance Rvi15 (Vr2) from the accession GMAL 2473 was genetically mapped, and three candidate resistance genes were identified. Here, we report the cloning and functional characterization of these three

Structure, dynamics and domain organization of the repeat protein Cin1 from the apple scab fungus

NARCIS (Netherlands)

Mesarich, C.H.; Schmitz, M.; Tremouilhac, P.; McGillivray, D.J.; Templeton, M.D.; Dingley, A.J.

2012-01-01

Venturia inaequalis is a hemi-biotrophic fungus that causes scab disease of apple. A recently-identified gene from this fungus, cin1 (cellophane-induced 1), is up-regulated over 1000-fold in planta and considerably on cellophane membranes, and encodes a cysteine-rich secreted protein of 523 residues

Cisgenic Rvi6 scab-resistant apple lines show no differences in Rvi6 transcription when compared with conventionally bred cultivars

NARCIS (Netherlands)

Chizzali, Cornelia; Gusberti, Michele; Schouten, H.J.; Gessler, Cesare; Broggini, G.A.L.

2016-01-01

Main conclusion: The expression of the apple scab resistance geneRvi6in different apple cultivars and lines is not modulated by biotic or abiotic factors.All commercially important apple cultivars are susceptible to Venturia inaequalis, the causal organism of apple scab. A limited number of apple

Evidence for sexual reproduction in Venturia effusa, causal agent of pecan scab

Science.gov (United States)

Pecan scab caused by Venturia effusa is widespread across southwest USA and epidemics can result in catastrophic yield loss. Venturia effusa reproduces asexually during the active phase of the disease cycle (spring through summer) with no evidence of a sexual cycle. Yet, genetic diversity among popu...

Effectiveness of short-term numerical weather prediction in predicting growing degree days and meteorological conditions for apple scab appearance

Czech Academy of Sciences Publication Activity Database

Lalic, B.; Francia, M.; Eitzinger, Josef; Podrascanin, Z.; Arsenic, I.

2016-01-01

Roč. 23, č. 1 (2016), s. 50-56 ISSN 1350-4827 Institutional support: RVO:86652079 Keywords : venturia-inaequalis * temperature * equation * schemes * model * numerical weather prediction * disease prediction * verification * apple scab * growing degree days Subject RIV: DG - Athmosphere Sciences, Meteorology OBOR OECD: Meteorology and atmospheric sciences Impact factor: 1.411, year: 2016

Venturia chinensis sp. nov., a new venturialean ascomycete from Khingan Mountains

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Jiaqi Zhang

2016-09-01

Full Text Available A new species of Venturia (V. chinensis is described and illustrated from the leaves of Lonicera praeflorens collected from Lesser Khingan Mountains, the northeast China. It is characterized by habitat saprobic; ascomata small-sized, solitary or scattered, superficial, subglobose to citriform, wall black, papillate, ostiolate, covered with setae; peridium thin; hamathecium evanescent in mature ascomata; asci 8-spored, bitunicate, fissitunicate, oblong to obclavate, with or without a short, knob-like pedicel; ascospores ellipsoidal, olivaceous pale brown, 1-septate, ascospore wall thin, smooth. Comparisons of V. chinensis with V. lonicerae (another species on Lonicera caerulea and other species of Venturia lead to the conclusion that collected taxon is new. Its relationships with other species of Venturia are discussed based on morphology and 28S nrDNA and ITS nrDNA sequence comparisons.

In vitro evidence for sexual reproduction in Venturia effusa, causal agent of pecan scab

Science.gov (United States)

Venturia effusa is the causal agent of pecan scab, the most prevalent disease of pecan in the southeastern US. Venturia effusa is currently only known to reproduce asexually, yet the genetic diversity among populations of pecan scab suggest it is a sexually reproducing pathogen. Analysis of the mati...

Halofunctionalization of alkenes by vanadium chloroperoxidase from Curvularia inaequalis

NARCIS (Netherlands)

Dong, J.; Fernandez Fueyo, E.; Li, Jingbo; Guo, Zheng; Renirie, Rokus; Wever, Ron; Hollmann, F.

The vanadium-dependent chloroperoxidase from Curvularia inaequalis is a stable and efficient biocatalyst for the hydroxyhalogenation of a broad range of alkenes into halohydrins. Up to 1 200 000 TON with 69 s−1 TOF were observed for the biocatalyst. A bienzymatic cascade to yield epoxides as

RNA-Seq analysis reveals candidate genes for ontogenic resistance in Malus-Venturia pathosystem.

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Michele Gusberti

Full Text Available Ontogenic scab resistance in apple leaves and fruits is a horizontal resistance against the plant pathogen Venturia inaequalis and is expressed as a decrease in disease symptoms and incidence with the ageing of the leaves. Several studies at the biochemical level tried to unveil the nature of this resistance; however, no conclusive results were reported. We decided therefore to investigate the genetic origin of this phenomenon by performing a full quantitative transcriptome sequencing and comparison of young (susceptible and old (ontogenic resistant leaves, infected or not with the pathogen. Two time points at 72 and 96 hours post-inoculation were chosen for RNA sampling and sequencing. Comparison between the different conditions (young and old leaves, inoculated or not should allow the identification of differentially expressed genes which may represent different induced plant defence reactions leading to ontogenic resistance or may be the cause of a constitutive (uninoculated with the pathogen shift toward resistance in old leaves. Differentially expressed genes were then characterised for their function by homology to A. thaliana and other plant genes, particularly looking for genes involved in pathways already suspected of appertaining to ontogenic resistance in apple or other hosts, or to plant defence mechanisms in general. IN THIS WORK, FIVE CANDIDATE GENES PUTATIVELY INVOLVED IN THE ONTOGENIC RESISTANCE OF APPLE WERE IDENTIFIED: a gene encoding an "enhanced disease susceptibility 1 protein" was found to be down-regulated in both uninoculated and inoculated old leaves at 96 hpi, while the other four genes encoding proteins (metallothionein3-like protein, lipoxygenase, lipid transfer protein, and a peroxidase 3 were found to be constitutively up-regulated in inoculated and uninoculated old leaves. The modulation of the five candidate genes has been validated using the real-time quantitative PCR. Thus, ontogenic resistance may be the result

Genetic recombination in Venturia effusa, causal agent of pecan scab

Science.gov (United States)

Venturia effusa causes pecan scab, the most prevalent disease of pecan in the southeastern USA. Mating type idiomorphs were recently characterized and the sexual stage was subsequently produced in vitro. To investigate sexual reproduction and recombination of traits in V. effusa, select isolates wer...

Gene flow between arrhenotokous and thelytokous populations of Venturia canescens (Hymenoptera)

NARCIS (Netherlands)

Schneider, MV; Driessen, G; Beukeboom, LW; Boll, R; van Eunen, K; Selzner, A; Talsma, J; Lapchin, L

In the solitary parasitoid wasp Venturia canescens both arrhenotokously (sexual) and thelytokously (parthenogenetical) reproducing individuals occur sympatrically. We found in the laboratory that thelytokous wasps are able to mate, receive and use sperm of arrhenotokous males. Using nuclear

Towards durabale resistance to apple scab using cisgenes

OpenAIRE

Joshi, S.G.

2010-01-01

Apple (Malus x domestica) is one of the important fruit crops of the world. It is mainly cultivated in temperate regions. Apple fruit contains many health beneficial compounds which may play an important role in reducing cancer cell proliferation and lowering the level of cholesterol. Apple production can suffer from several pests and diseases and among them scab is very important. Apple scab is a fungal disease caused by Venturia inaequalis. The pathogen is a facultative saprophyte that gro...

Advances in Apple Transformation Technology to Confer Resistance to Fungal Diseases in Apple Crops: A Chilean Perspective Avances de la Tecnología de Transformación del Manzano para Conferir Resistencia a Enfermedades Fungosas en su Cultivo: Una Perspectiva Chilena

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Víctor Polanco

2010-06-01

Full Text Available Apple (Malus domestica Borkh. is one of the most consumed fruit in the world. Genetic transformation is a key process to sustain this demand by permitting the potential enhancement of existing cultivars as well as the development of new cultivars resistant to pests, diseases, and storage problems that occur in the major production areas. This review summarizes the advances of genetic engineering applied to the development of resistant apple cultivars to fungus disease, with particular attention in the generation of apples resistant to Venturia inaequalis (Cooke G.Winter, the main phytosanitary problem that affects apple crops in Chile.La manzana (Malus domestica Borkh. es una de las frutas más consumidas en el mundo. La transformación genética es un proceso clave para sustentar esta demanda, permitiendo el mejoramiento potencial de los cultivares existentes, así como el desarrollo de nuevas variedades resistentes a plagas, enfermedades y problemas de almacenamiento que se originan en las zonas de producción más importantes. Esta revisión resume los avances de la ingeniería genética aplicada al desarrollo de variedades de manzana resistentes a enfermedades fungosas, con especial atención en la generación de manzanas resistentes a Venturia inaequalis (Cooke G.Winter, el principal problema fitosanitario que afecta a los cultivos de manzana en Chile.

Mining and characterization of microsatellites from a genome of Venturia carpophila

Science.gov (United States)

A total of 4,021 microsatellites were mined from a genome of Venturia carpophila and 192 were selected to screen 39 isolates of the fungus collected from peach and nectarine in the southeastern USA. Of the 192 selected, 32 primers consistently and reliably produced polymorphic amplicons. Subsequentl...

Strategic irrigation against apple scab (Venturia inaequalis)

DEFF Research Database (Denmark)

Korsgaard, Maren

2012-01-01

the orchard floor, to force the ascospores to be released. We irrigated with at least 0.2 mm of water in dry periods, at least 12 hours before rain forecast. The idea was to empty the stock of ascospores during dry spells, so they would dry out without infecting the leaves. To find the best strategic times......, that the irrigation did result in ascospore-release, but the effect on the scab-attack was not significant. We also experienced, that the fruit growers found this way of preventing scab very interesting and easy to carry out. The pilot-trial was financed by “Fonden for Oekologisk Jordbrug” and in 2011...

Genome-wide SNP identification by high-throughput sequencing and selective mapping allows sequence assembly positioning using a framework genetic linkage map

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Xu Xiangming

2010-12-01

Full Text Available Abstract Background Determining the position and order of contigs and scaffolds from a genome assembly within an organism's genome remains a technical challenge in a majority of sequencing projects. In order to exploit contemporary technologies for DNA sequencing, we developed a strategy for whole genome single nucleotide polymorphism sequencing allowing the positioning of sequence contigs onto a linkage map using the bin mapping method. Results The strategy was tested on a draft genome of the fungal pathogen Venturia inaequalis, the causal agent of apple scab, and further validated using sequence contigs derived from the diploid plant genome Fragaria vesca. Using our novel method we were able to anchor 70% and 92% of sequences assemblies for V. inaequalis and F. vesca, respectively, to genetic linkage maps. Conclusions We demonstrated the utility of this approach by accurately determining the bin map positions of the majority of the large sequence contigs from each genome sequence and validated our method by mapping single sequence repeat markers derived from sequence contigs on a full mapping population.

Geographical distribution and genetic relatedness of sympatrical thelytokous and arrhenotokous populations of the parasitoid Venturia canescens (Hymenoptera)

NARCIS (Netherlands)

Schneider, M.V.; Beukeboom, L.W.; Driessen, G.; Lapchin, L.; Bernstein, C.; Alphen, J.J.M. van

2002-01-01

Theory predicts that asexual reproduction has a competitive advantage over sexual reproduction because of the twofold cost of producing males. Few systems are suitable for directly testing this prediction. In the solitary parasitoid wasp Venturia canescens both arrhenotokously (sexual) and

Evidence for the presence of an endosymbiont in the Pecan Scab pathogen Venturia effusa (basyonym: Fusicladium effusum)

Science.gov (United States)

Aims: To determine whether Venturia effusa (basyonym: Fusicladium effusum) the causative fungal agent of Pecan Scab harbors a bacterial symbiont. Methods and Results: Beginning with monoconidial isolates, V. effusa was maintained on potato dextrose agar amended with antibiotics (chloramphenicol 10...

Obelų selekcinių numerių biologinių savybių tyrimas

OpenAIRE

Gelvonauskienė, Dalia; Sasnauskas, Audrius; Gelvonauskis, Bronislovas; Šikšnianienė, Jūratė Bronė; Šabajevienė, Gintarė; Duchovskis, Pavelas

2006-01-01

2000–2006 m. Lietuvos sodininkystės ir daržininkystės institute tirtos šešiolikos selekcinių numerių obelų (Malus domestica Borkh.) biologinės savybės. Įvertinta vaismedžių su M.26 poskiepiu (4 x 2,5 m) fenologija, žiedų ir ūglių pašalimas, vaismedžių augumas, atsparumas rauplėms (Venturia inaequalis (Cke) Wint.), filostiktozei (Phyllosticta mali Pr. at Del.), vėžiui (Nectria galligena Bres.) bei fotosintezės pigmentų kiekis lapuose. Nustatyta, kad anksčiausiai žydėti baigia Nr. 19646, o ...

How Did Host Domestication Modify Life History Traits of Its Pathogens?

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Marie De Gracia

Full Text Available Understanding evolutionary dynamics of pathogens during domestication of their hosts and rise of agro-ecosystems is essential for durable disease management. Here, we investigated changes in life-history traits of the fungal pathogen Venturia inaequalis during domestication of the apple. Life traits linked to fungal dispersal were compared between 60 strains that were sampled in domestic and wild habitats in Kazakhstan, the center of origin of both host and pathogen. Our two main findings are that transition from wild to agro-ecosystems was associated with an increase of both spore size and sporulation capacity; and that distribution of quantitative traits of the domestic population mostly overlapped with those of the wild population. Our results suggest that apple domestication had a considerable impact on fungal characters linked to its dispersal through selection from standing phenotypic diversity. We showed that pestification of V. inaequalis in orchards led to an enhanced allocation in colonization ability from standing variation in the wild area. This study emphasizes the potential threat that pathogenic fungal populations living in wild environments represent for durability of resistance in agro-ecosystems.

The mange of the peartree (Venturia Pyrina, experience in transfer of technology

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Carlos Espinosa

2008-10-01

Full Text Available A program of technology transfer was implemented in themunicipality of Nuevo Colón, with the purpose to maintainthe roña or scabies of the peach tree with levels of damagebelow the economic threshold, by means of participatorymethodologies, identifying the current processes used byproducers in the control of Venturia, as well as the alternativesfor the roña or scabies control that allow to establish aprogram of the illness management and, at the same time,to develop transfer program by means of the fruit-culturerstraining in methods for the cultivation handling with emphasison the control of Venturia pyrina, conducting a permanentevaluation and feedback with the results of the validatedalternatives.The purpose was to implement control practices in 10 demonstrativeplots by marking 10 trees of each one of them,as well as to replicate the control in 400 orchards during thethree years of the project, train 400 fruit-culturers in phytosanitaryproduction and cultivation alternative techniques.The incidence of the disease decreased 40% the first year,60% the second one and 80% the third one. There were 400primers and 3 videos left as memories an reinforcement oftraining.The results were the establishment of control practices in300 orchards during the three-year period of the project, thetraining of 300 fruit-culturers in production, alternative techniquesfor cultivation and phytosanitary control, the decreaseof the disease incidence by 30% the first year, 70% thesecond year and 85% the third year. In addition, there wereleft as memory 500 primers with optimal and convenientsolutions as successful technological alternatives that wereadopted and implemented by the 87% of pear producers.

Cisgenic Rvi6 scab-resistant apple lines show no differences in Rvi6 transcription when compared with conventionally bred cultivars.

Science.gov (United States)

Chizzali, Cornelia; Gusberti, Michele; Schouten, Henk J; Gessler, Cesare; Broggini, Giovanni A L

2016-03-01

The expression of the apple scab resistance gene Rvi6 in different apple cultivars and lines is not modulated by biotic or abiotic factors. All commercially important apple cultivars are susceptible to Venturia inaequalis, the causal organism of apple scab. A limited number of apple cultivars were bred to express the resistance gene Vf from the wild apple genotype Malus floribunda 821. Positional cloning of the Vf locus allowed the identification of the Rvi6 (formerly HcrVf2) scab resistance gene that was subsequently used to generate cisgenic apple lines. It is important to understand and compare how this resistance gene is transcribed and modulated during infection in conventionally bred cultivars and in cisgenic lines. The aim of this work was to study the transcription pattern of Rvi6 in three classically bred apple cultivars and six lines of 'Gala' genetically modified to express Rvi6. Rvi6 transcription was analyzed at two time points using quantitative real-time PCR (RT-qPCR) following inoculation with V. inaequalis conidia or water. Rvi6 transcription was assessed in relation to five reference genes. β-Actin, RNAPol, and UBC were the most suited to performing RT-qPCR experiments on Malus × domestica. Inoculation with V. inaequalis conidia under conditions conducive to scab infection failed to produce any significant changes to the transcription level of Rvi6. Rvi6 expression levels were inconsistent in response to external treatments in the different apple cultivars, and transgenic, intragenic or cisgenic lines.

Efficacy of Strobilurin-related and Multi-site Fungicide Mixtures Against Apple Scab

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Emil Rekanović

2007-01-01

Full Text Available The efficacy of several fungicide mixtures in controlling Venturia inaequalis in apple was evaluated in field trials. The efficacies of Flint Plus (trifloxystrobin + captan and Tercel (pyraclostrobin+ dithianon in comparison with standard fungicides Zato 50-WG (trifloxystrobin and Stroby + Delan (kresoxim-methyl + dithianon were tested in the localities Mihajlovac, Radmilovac and Landol in 2004 and 2005. Both tested fungicides exhibited high efficacy in controlling apple scab. There were significant differencies in the efficacies of Flint Plus (91.3-98.5% and Zato 50-WG (68.2% and 78.4%; and Tercel (88.7-93.5% and Stroby + Delan (77.9% and 82.1%. Our experiments showed that the investigated fungicide mixtures arehighly effective against V. inaqeulais, even under high disease pressure.

Fine scale population genetic structure and within tree distribution of mating types of Venturia effusa, cause of pecan scab in the USA

Science.gov (United States)

Scab (caused by Venturia effusa) is the major disease of pecan in the southeastern USA. There is no information available on the fine scale population genetic diversity. Four cv. Wichita trees (populations) were sampled hierarchically. Within each tree canopy, 4 approximately evenly spaced terminals...

Transcriptome and proteome analysis of ovaries of arrhenotokous and thelytokous Venturia canescens.

Science.gov (United States)

Mateo Leach, I; Hesseling, A; Huibers, W H C; Witsenboer, H; Beukeboom, L W; van de Zande, L

2009-08-01

Under arrhenotoky, unfertilized haploid eggs develop as males but under thelytoky they develop into diploid females after they have undergone diploidy restoration. In the parasitoid wasp Venturia canescens both reproductive modes occur. Thelytoky is genetically determined but the underlying genetics of diploidy restoration remain unknown. In this study we aim to identify the genes and/or proteins that control thelytoky. cDNA-amplified fragment length polymorphism (cDNA-AFLP) analysis of total ovarian RNA and two-dimensional protein electrophoresis in combination with mass spectrometry revealed putative transcripts and proteins involved in arrhenotokous and thelytokous development. The detected tubulin and actin protein differences are most likely functionally related to the two types of reproduction.

Influence of different disease control pesticide strategies on multiple pesticide residue levels in apple

DEFF Research Database (Denmark)

Poulsen, Mette Erecius; Naef, A.; Gasser, S.

2009-01-01

Seven pesticide application strategies were investigated to control apple scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) and, at the same time.. fulfil the new quality standards implemented by some German retailers. These demand that pesticide residues should be below 80....... The trials were conducted at two sites in Switzerland, in 2007, and all strategies and applications were in accordance with actual practice. Four replicates of apple samples from each strategy were then analysed for pesticide residues. The incidence of infection with apple scab and powdery mildew were...... monitored during the season in order to evaluate the efficacy of the different strategies. The efficacies of the different strategies against apple scab and powdery mildew were between 84% and 100% successful. In general, the level of pesticide residues found correlated with application rate and time...

Evidence for the presence of a bacterial endosymbiont in the pecan scab pathogen Venturia effusa (basyonym: Fusicladium effusum).

Science.gov (United States)

Medrano, E G; Grauke, L J; Stanford, R L; Thompson, T E

2017-08-01

To determine whether Venturia effusa, the causative fungal agent of pecan scab, harbours a bacterial symbiont. Venturia effusa isolates were maintained on potato dextrose agar amended with antibiotics (chloramphenicol (100 μg ml -1 ) and tetracycline 100 (μg ml -1 )). Genomic DNA extracted from mycelia was used to target eubacterial 16S rDNA. A 1·4-kbp PCR amplified product using 16S rDNA degenerate primers was cloned, sequenced and found to have 99% identities with Actinobacteria representatives. Attempts to culture the detected bacteria apart from the fungus following agitation and fungal cell lysis were unsuccessful using standard bacteriological media under either aerobic or anaerobic conditions. Fungal structures were visualized using scanning electron microscopy and putative bacterial formations associated with the fungal mycelia were observed. Fluorescence in situ hybridization using 16S rDNA oligonucleotides illuminated spores and portions of the hyphae. This is the first report to provide both molecular microbiological and microscopic evidence in support of the hypothesis that V. effusa harbours endosymbiotic bacteria. Findings from this research contribute fundamental information regarding the biology of the fungus that may ultimately lead to identifying a target of the pathogen for use in management and/or avoidance strategies. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Development of Carrot Medium Suitable for Conidia Production of Venturia nashicola

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Eu Ddeum Choi

2017-02-01

Full Text Available The causal fungus of pear scab, Venturia nashicola, grows slowly and rarely produces conidia on artificial media in the laboratory, but it produced conidia on the Cheongah medium containing Cheongah powder. V. nashicola grew too slow to produce conidia until 15 days after cultivation but produced conidia with 4 × 10⁴ conidia/plate 30 days after cultivation on the Cheongah medium containing 1% Cheongah powder. V. nashicola showed a peak production of conidia with 4.5 × 10⁵ conidia/plate 60 days after cultivation on the carrot medium containing 2% carrot powder, one of the constituents of Cheongah powder. The carrot medium is considered to be the best medium to obtain conidia of V. nashicola in the laboratory until now. This is the first report on the development of a suitable medium for conidia production of V. nashicola, as far as we know.

When a Plant Resistance Inducer Leaves the Lab for the Field: Integrating ASM into Routine Apple Protection Practices.

Science.gov (United States)

Marolleau, Brice; Gaucher, Matthieu; Heintz, Christelle; Degrave, Alexandre; Warneys, Romain; Orain, Gilles; Lemarquand, Arnaud; Brisset, Marie-Noëlle

2017-01-01

Plant resistance inducers, also called elicitors, could be useful to reduce the use of pesticides. However, their performance in controlling diseases in the field remains unsatisfactory due to lack of specific knowledge of how they can integrate crop protection practices. In this work, we focused on apple crop and acibenzolar- S -methyl (ASM), a well-known SAR (systemic acquired resistance) inducer of numerous plant species. We provide a protocol for orchard-effective control of apple scab due to the ascomycete fungus Venturia inaequalis , by applying ASM in combination with a light integrated pest management program. Besides we pave the way for future optimization levers by demonstrating in controlled conditions (i) the high influence of apple genotypes, (ii) the ability of ASM to prime defenses in newly formed leaves, (iii) the positive effect of repeated elicitor applications, (iv) the additive effect of a thinning fruit agent.

Apple cultivars resistant to scab (Venturia inaequalis (Cke. Aderh. Part II. Winterhardiness of apple cultivars

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Zbigniew Borecki

2013-12-01

Full Text Available The severe winter which occurred in Poland in 1986-1987 damaged the most part of scab resistant apple cultivars and selected apple hybrids. Cold hardiness studied in 1987 and 1988 showed significant differences in degree of frost injury on stem, branches, twigs and buds of apple trees. Two scab-resistance cultivars, namely Florina and Sir Prize, as well as two check culuvars, Idared and Golden Delicious, were killed by frost. Strong damages were noted in cultivars: Prima, Primula, and Priam. Lower susceptibility showed: Jonafree, Gavin, Liberty Sister and three hybrids selected from crosses of Bankroft with scab-resistant Primula. Relatively frost resistant was Novamac and three hybrids of U-breeding line: U-1101 and U-50, originated from crosses of polish culrivar Fantazja (McIntosh x Linda with Primula, Highest resistance to frost showed cultivars: Freedom. Liberty. new polish cultivar Witos (Fantazja x Primula and three hybrids: U-337, U-237 and U-1098. During the 1987 and 1988 seasons severe infection of apple trees by numerous fungi was noted. Twelve species of isolated fungi were identified as pathogens of apple trees bark and wood.

Purification and general properties of pectin methyl esterase from Curvularia inaequalis NRRL 13884 in solid state culture using orange peels as an inducer.

Science.gov (United States)

Afifi, A F; Fawzi, E M; Foaad, M A

2002-01-01

Pectin methyl esterase (PME) [E.C.3. 1.1.11] production by Curvularia inaequalis (Shear) Boedijn NRRL 13884 was investigated using solid-state culture. The highest level of extracellular pectin methyl esterase was detected with orange peels as an inducing substrate and as a sole carbon source. The enzyme was partially purified using Sephadex G-100 and DEAE-Cellulose column chromatography. It was purified about 40 fold with optimum activity at pH 4.4 and 45 degrees C. The enzyme was activated by Co++, Mg++, Na+, whereas it was slightly activated in the presence of Cu++, K+, Mn++, Zn++. On the other hand Ag++, Ca++ and Hg++ inhibited the activity of the enzyme. The Km was calculated to be 0.52 mM.

Nuclear magnetic resonance microscopy of the development of the parasitoid wasp Venturia canescens within its host moth Plodia interpunctella.

Science.gov (United States)

Chudek, J A; Crook, A M; Hubbard, S F; Hunter, G

1996-01-01

Nuclear magnetic resonance microscopy was used to image the parasitoid wasp Venturia canescens (Hymenoptera: Ichneumonidae) within larval and pupal instars of its host, the Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae). The images were obtained using gradient-echo and chemical shift selective pulse sequences and clearly showed the location and shapes of the parasitoid as it developed from the L1 larva to a pupal stage within the host. The digestive, nervous, and tracheal systems of the host were identified and changes were observed as the host underwent metamorphosis. Destruction of the host tissues by the parasitoid was visible. It was found that the parasitoid first ate the fat body and digestive system of the host, allowing the host to continue to grow, and only progressed to the vital organs when its own development had neared pupation.

Relationship of Resistance to Benzimidazole Fungicides with Mutation of β-Tubulin Gene in Venturia nashicola

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Yeonsoo Kwak

2017-06-01

Full Text Available Pear scab caused by Venturia nashicola has been reported as an important disease of pear resulting in lowering the quality of pear fruits. In this study, it was conducted to investigate the relationship between resistance of V. nashicola and mutation of β-tubulin gene and the fungicide resistance in field isolate group in benzimidazole fungicides. Responce of V. nashicola to carbendazim could be classified into 3 groups as sensitive that does not grow at all on PDA amended with 0.16 μg/ml of carbendazim, low resistance that could not grow in 4.0 μg/ml medium, and high resistance that can grow even at 100 μg/ml. Thirty isolates of V. nashicola collected from 3 regions as Wonju, Naju, and Okcheon were highly resistant to carbendazim. Analysis of the nucleotide sequence of β-tubulin gene of V. nashicola showed that there was no difference in the nucleotide sequence between the sensitive and the low-resistant isolate, but GAG at codon 198 (glutamic acid was replaced with GCG (alanine in the high-resistant isolate. Among 10 isolates obtained from the Okcheon, 5 isolates showed the substitution of glycine for glutamic acid, which were resistant to carbendazim, but more sensitive to the mixture of carbendazim and diethofencarb than others. Through these results, all isolates of V. nashicola isolated in pear orchard were found to be resistant to benzimidazoles. Also, mutants E198A and E198G at β-tubulin were found to be important mechanisms of V. nashicola resistance against benzimidazole fungicides.

Population Genetic Structure of Venturia effusa, Cause of Pecan Scab, in the Southeastern United States.

Science.gov (United States)

Bock, Clive H; Hotchkiss, Michael W; Young, Carolyn A; Charlton, Nikki D; Chakradhar, Mattupalli; Stevenson, Katherine L; Wood, Bruce W

2017-05-01

Venturia effusa is the most important pathogen of pecan in the southeastern United States. Little information exists on the population biology and genetic diversity of the pathogen. A hierarchical sampling of 784 isolates from 63 trees in 11 pecan orchards in the southeastern United States were screened against a set of 30 previously characterized microsatellite markers. Populations were collected from Georgia (n = 2), Florida (n = 1), Alabama (n = 2), Mississippi (n = 1), Louisiana (n = 1), Illinois (n = 1), Oklahoma (n = 1), Texas (n = 1), and Kansas (n = 1). Clonality was low in all orchard populations (≤10.1% of isolates), and there were consistently high levels of genotypic diversity (Shannon-Weiner's index = 3.49 to 4.59) and gene diversity (Nei's measure = 0.513 to 0.713). Analysis of molecular variance showed that, although 81% of genetic diversity occurred at the scale of the individual tree, 16% occurred between orchards and only 3% between trees within orchards. All populations could be differentiated from each other (P = 0.01), and various cluster analyses indicated that some populations were more closely related compared with other pairs of populations. This is indicative of some limited population differentiation in V. effusa in the southeastern United States. Bayesian and nearest-neighbor methods suggested eight clusters, with orchards from Georgia and Florida being grouped together. A minimum spanning tree of all 784 isolates also indicated some isolate identification with source population. Linkage disequilibrium was detected in all but one population (Kansas), although 8 of the 11 populations had pecan and pecan scab, which is that V. effusa became an issue on cultivated pecan in the last approximately 120 years (recent population expansion). Recently reported mating type genes and the sexual stage of this fungus may help explain the observed population characteristics, which bear a strong resemblance to those of other well

Controle de pragas e doenças, maturação e qualidade de maçãs 'imperial gala' submetidas ao ensacamento Control of insect pests and diseases, maturity and quality of 'imperial gala' apples submitted to bagging

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Rosângela Teixeira

2011-06-01

Full Text Available O objetivo deste trabalho foi avaliar a eficiência de diferentes embalagens no ensacamento de maçãs para o controle de pragas e doenças, e sua influência na maturação e qualidade dos frutos, em pomar sob sistema orgânico. O experimento foi conduzido em pomar com plantas de dez anos de idade da cultivar Imperial Gala, sobre porta-enxerto 'Marubakaido', com filtro EM-9, localizado no município de São Joaquim-SC, nas safras 2007/2008 e 2008/2009. Os frutos foram ensacados, após o raleio, com embalagens plásticas transparentes microperfuradas ou de tecido não texturizado (TNT. Frutos não ensacados constituíram o tratamento-controle. Na colheita, os frutos foram avaliados quanto aos danos provocados por mosca-das-frutas (Anastrepha fraterculus, mariposa-oriental (Grapholita molesta, lagarta-enroladeira (Bonagota salubricola e pulgão-lanígero (Eriosoma lanigerum, incidência das doenças sarna-da-macieira (Venturia inaequalis e podridão-amarga (Colletotrichum gloeosporioides, e atributos físico-químicos de maturação e qualidade e teor de cálcio (Ca nos frutos. O ensacamento, independentemente do tipo de material utilizado, reduziu os danos de insetos-praga, porém não foi eficiente no controle de doenças nos frutos. O ensacamento não comprometeu o desenvolvimento de coloração vermelha na casca e o teor de Ca nos frutos. De modo geral, o ensacamento antecipou o processo de maturação, caracterizado pela redução na firmeza de polpa e na textura da casca e da polpa, e pelo aumento no índice de iodoamido.This work was carried out to evaluate the efficiency of different fruit bagging materials to insect pests and diseases control, and its influence on maturity and quality of the fruits in an organic apple orchard. The experiment was conducted in an orchard with ten years old 'Imperial Gala' apple trees grafted on 'Marubakaido' rootstock (with a filter of EM-9, in São Joaquim, State of Santa Catarina, in 2007/08 and 2008

Perspectives de lutte contre les maladies des arbres fruitiers à pépins au moyen de substances naturelles inductrices d'une résistance systémique

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Lateur M.

2002-01-01

Full Text Available Natural compounds used as elicitors of systemic induced resistance offer new prospects to control pome fruit tree diseases. This review presents a new way of plant protection for pome fruit tree diseases as a potential response to the very high use of pesticides in commercial production with the view to reduce their negative side-effects on environment and human health. Work is focused on examples of use of elicitors from natural origin which induce systemic resistance for controlling two important diseases as apple scab (Venturia inaequalis and fire blight (Erwinia amylovora. Many factors limit today their practical use: their efficacy is only partial and in interaction with plants and environment; much work has to be done to improve the formulation and to determine doses and rates of application, the right phenologic application times, and finally they are often submitted to the normal high standards of Plant Protection Products Regulations which are long, very expensive and not adapted to compounds which can have a very complex composition. In other hands, this new way of plant protection presents many potential advantages: using relatively simple, not expensive, non toxic natural compounds with a good image; polyvalent and broad field of action; non-specific and multi-side action which offer a good durability of action; systemic action in the plants during a relative long period of time and the possibility to control difficult bacterial diseases and more surprisingly viral diseases. The multiple advantages presented offer valuable prospects for a better friend-environmentally way to control pome fruit diseases in the next future.

Incidence-severity relationships for scab on foliage and fruit of pecan

Science.gov (United States)

Venturia effusa is the causal agent of pecan scab, the most prevalent disease of pecan in the southeastern US. Venturia effusa is currently only known to reproduce asexually, yet the genetic diversity among populations of pecan scab suggest it is a sexually reproducing pathogen. Analysis of the mati...

Sensitivity of promising cherry hybrids and new cultivars to economically important fungal diseases

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K. Vasileva

2016-09-01

Full Text Available Abstract. As a result of years of developing the breeding programme for creating novel sweet cherry cultivars in the Fruit Growing Institute (FGI, Plovdiv, a reach hybrid fund from first and second hybrid generation is created. Of the selected and propagated hybrids at a more advanced stage of testing are 11 hybrids along with three new cultivars of the FGI Plovdiv ('Kossara', 'Rosalina' and 'Trakiiska hrushtyalka' grafted on three rootstocks were tested for sensitivity to causers of economically important fungal diseases in sweet cherry - cherry leaf spot (Blumeriella jaapii (Rehm Arx, shothole blight (Stigmina carpophila (Lev. Ellis and brown rot (Monilinia fructigena (G. Wint Honey. The degree of infestation under field conditions is reported by determining the index of attack on leaves and fruit, using the formula of McKinney. As the most sensitive elites are outlined elite El.17-31 (to cherry leaf spot and elite El.17-136 (to shothole blight. The cultivars 'Kossara' and 'Trakiiska hrushtyalka' exhibit an average resistance to the three diseases, as the values for the index of infestation are lower or similar to those of standard cultivars 'Van' and 'Bing', while 'Rosalina' demonstrated sensitivity to shothole blight and brown rot. Interesting is the elite El.17- 37 demonstrating the least infestation of Blumeriella jaapii - 7.33% and Monilinia fructigena - 6.67%. The same has a set of valuable qualities as late maturing date and very large fruits with excellent sensory profile, making it a potential candidate cultivar.

Molecular and morphological analysis reveals five new species of Zygophiala associated with flyspeck signs on plant hosts from China.

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Liu Gao

Full Text Available Species in the genus Zygophiala are associated with sooty blotch and flyspeck disease on a wide range of hosts. In this study, 63 Zygophiala isolates collected from flyspeck colonies on a range of plants from several regions of China were used for phylogeny, host range and geographic distribution analysis. Phylogenetic trees were constructed on four genes--internal transcribed spacer (ITS, partial translation elongation factor 1-alpha (TEF, β-tubulin (TUB2, and actin (ACT--both individually and in combination. Isolates were grouped into 11 clades among which five new species, Z. emperorae, Z. trispora, Z. musae, Z. inaequalis and Z. longispora, were described. Species of Zygophiala differed in observed host range and geographic distribution. Z. wisconsinensis and Z. emperorae were the most prevalent throughout the sampled regions of China, whereas Z. trispora, Z. musae, Z. inaequalis and Z. longispora were collected only in southern China. The hosts of Z. wisconsinensis and Z. emperorae were mainly in the family Rosaceae whereas Z. trispora, Z. musae, Z. inaequalis and Z. longispora were found mainly on banana (Musa spp.. Cross inoculation tests provided evidence of host specificity among SBFS species.

Crystal structure of a trapped phosphate intermediate in vanadium apochloroperoxidase catalyzing a dephosphorylation reaction

NARCIS (Netherlands)

de Macedo-Ribeiro, S.; Renirie, R.; Wever, R.; Messerschmidt, A.

2008-01-01

The crystal structure of the apo form of vanadium chloroperoxidase from Curvularia inaequalis reacted with para-nitrophenylphosphate was determined at a resolution of 1.5 Å. The aim of this study was to solve structural details of the dephosphorylation reaction catalyzed by this enzyme. Since the

Efficacy of Bordeaux mixture to control pecan scab in large-plot experiments

Science.gov (United States)

Venturia effusa causes scab, the most important disease on pecan in the southeastern USA. Organic fungicides have not been widely tested for efficacy against scab on susceptible cultivars. A large-plot experiment was used to test the efficacy of the traditionally-used fungicide against scab, Bordeau...

New bacterial products for control of pecan pests

Science.gov (United States)

Pecans are economically the most important native nut crop in the USA. Among the major concerns are the pecan weevil (Curculio caryae), pecan aphids, and diseases such as pecan scab, Venturia effusa. These pests are generally controlled with broad spectrum chemicals. The chemical pesticides can be...

Comparing protection afforded by different organic alternatives to conventional fungicides for reducing scab on pecan

Science.gov (United States)

Pecan scab (Venturia effusa) is the major yield-limiting disease in the southeastern USA. Although conventional fungicides are available to manage the disease, there is no comparison of organic methods (organically produced nuts attract a higher price). In 2011, 2012, 2014, 2015 and 2016 trees of cv...

Chlorination of lignin by ubiquitous fungi has a likely role in global organochlorine production

Science.gov (United States)

Patricia Ortiz-Bermudez; Kolby C. Hirth; Ewald Srebotnik; Kenneth E. Hammel

2007-01-01

Soils and decayed plant litter contain significant quantities of chlorinated aromatic polymers that have a natural but largely unknown origin. We used cupric oxide ligninolysis coupled with gas chromatography/mass spectrometry to show that Curvularia inaequalis, a widely distributed litter ascomycete, chlorinated the aromatic rings of lignin in wood that it was...

Chlorination and cleavage of lignin structures by fungal chloroperoxidases

Science.gov (United States)

Patricia Ortiz-Bermudez; Ewald Srebotnik; Kenneth E. Hammel

2003-01-01

Two fungal chloroperoxidases (CPOs), the heme enzyme from Caldariomyces fumago and the vanadium enzyme from Curvularia inaequalis, chlorinated 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxypropane, a dimeric model compound that represents the major nonphenolic structure in lignin. Both enzymes also cleaved this dimer to give 1-chloro-4-ethoxy-3-...

Geographic variation in ectoparasitic mites diversity in Tadarida Brasiliensis (Chiroptera, Molossidae

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Tatiana C. Pesenti

2014-12-01

Full Text Available Tadarida brasiliensis (Geoffroy, 1824, the Brazilian free-tailed bat, is an insectivorous bat that occurs from southern United States of America to southern South America. In this study we present the first data on diversity of ectoparasitic mites of T. brasiliensis in Brazil. A compilation and analysis of the studies of mite diversity conducted in different points the geographic distribution this bat species are provided. The mites were collected from March 2010 to November 2011 on 160 T. brasiliensis adult bats captured in southern Brazil. Four species of mites have been found: Chiroptonyssus robustipes (Ewing, 1925, Ewingana longa (Ewing, 1938, Ewingana inaequalis (Radford, 1948, and specimens of Cheyletidae. Chiroptonyssus robustipes was the most prevalent species (100%, followed by E. longa (20%, E. inaequalis (10%, and specimens of Cheyletidae (1.25%. The data currently available show that C. robustipes parasitizes T. brasiliensis throughout its region of occurrence, and this mite is highly prevalent and abundant. The two species of Ewingana accompany the geographical distribution of T. brasiliensis, but with much lower prevalence and abundance.

A comparison of ground-based air-blast sprayer and aircraft application of fungicides to manage scab in tall pecan trees

Science.gov (United States)

Scab (caused by Venturia effusa) is the most destructive disease of pecan in the southeastern USA. The most widely used method to apply fungicide is air-blast (AB) sprayers. Aerially (A) applied sprays are also used, but the disease distribution and spray coverage of these two methods has not been c...

Primary scab control using a "during-infection" spray timing and the effect on fruit quality and yield in organic apple production

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Jamar, L.

2010-01-01

Full Text Available Organic apple production in Europe depends to a great extent on the use of copper fungicides for scab control (Venturia inaequalis. The objective of this 6-year study (2003-2008 conducted in Belgium was to determine measures for reducing the use of copper fungicides in organic apple production. The effectiveness of a 'during-infection' spray strategy using wettable sulphur (with or without copper, lime sulphur, potassium bicarbonate, silicon and five natural plant extracts (orange peel, soapbark, tea seed, quinoa seed and grapefruit seed for controlling primary scab was investigated in a split-plot field experiment. Four apple cultivars that express a gradient of partial scab resistance were included: a high scab-susceptible cultivar (cv. 'Pinova', a medium scab-susceptible cultivar (cv. 'Pirouette' and two old cultivars expressing low to very low scab susceptibility (cvs. 'Reinette Hernaut' and 'Reinette des Capucins'. Apart from these cultivars, four monogenic Vf scab-resistant cultivars (cvs. 'Initial', 'Topaz', 'Zvatava' and 'JN 20/33/58' were also included in the experimental orchard. In order to reduce the amount of fungicide required, two strategies were used: a specific spray timing involving spraying during the infection processes, before fungal penetration, determined by the RIMpro software warning system, and a tunnel sprayer machine for optimal treatment applications. Depending on the year, a total of 8-12 applications were made annually. Under field conditions that were highly conducive disease, low rates of elemental sulphur (≤ 40 kg.ha-1 per year combined with low rates of copper (≤ 2.1 kg.ha-1 per year provided the best scab control and reduced scab severity on the leaves and fruits by 85-100%, depending on the year and cultivar, compared with the untreated control. In most cases, the lime sulphur spray treatment, which used more elemental sulphur but did not use copper, provided a similar level of scab control to the

The parasitoids of the African white rice borer, Maliarpha separatella Ragonot (Lepidoptera: Pyralidae)

OpenAIRE

Polaszek, A.; Fitton, M.G.; Bianchi, G.; Huddleston, T.

2017-01-01

A key is provided for the recognition of the hymenopterous parasitoids of the African white rice borer, Maliarpha separatella Ragonot, a pest of rice in Africa and Madagascar. Five species are described as new: Braconidae: Chelonus maudae Huddleston, Rhacanotus carinafus Polaszek; Ichneumonidae: Prisfomerus bullis Fitton, Prisfomerus caris Fitton, Venturia jordanae Fitton. The following synonyms are proposed: Goniozus indicus Muesebeck, G. natalensis Gordh and G. procerae Risbec are synonymiz...

Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

OpenAIRE

Amat, I; Kacelnik, A; van Alphen, JJM; Desouhant, E; Bernstein, C

2017-01-01

Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals in...

Lifetime reproductive success in the solitary endoparasitoid, Venturia canescens

NARCIS (Netherlands)

Harvey, J.A.; Harvey, I.F.; Thompson, D.J.

2001-01-01

Parasitoid wasps have long been considered excellent organisms in studies examining the evolution of reproductive and life- history strategies. In examining the lifetime reproductive success of parasitoids in the laboratory, most investigations have provided the insects with excess hosts and food,

Aspectos bionômicos de Eois tegularia (Guenée e Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae e seus parasitóides Bionomic aspects of Eois tegularia (Guenée and Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae and their parasitoids

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Sandra Maria Pasenow Braga

2001-09-01

Full Text Available Eois tegularia (Guenée, [1858] and Eois glauculata (Walker, [1863] larvae were studied by one year in semidec iduous forest at Canchim Farm (EMBRAPA, São Carlos, São Paulo, Brazil. Specimens were hosted by species of Piper Linnaeus (Piperaceae: P. mollicomum Kunth, P. amalogo Linnaeus, P. glabratum Kunth and P. gaudichaudianum Kunth. Some parasitoids were reared from the larvae of Eois Hübner, 1818 species, as follow. Hymenoptera: Cotesia Cameron, 1891, Apanteles Foerster, 1862, Glyptapanteles Ashmead, 1904, Dolichogenidea Viereck, 1911, Meteorus Haliday, 1835 (Braconidae; Mesochorus Gravenhorst, 1829, Venturia Schrottky, 1902 (Ichneumonidae; Elachertus Spinola, 1811 (Eulophidae; Perilampus Latreille, 1809 (Perilampidae, Diptera: Myiopharus Brauer & Bergenstamm, 1889 (Tachinidae.

Selection of autochthonous sour cherry (Prunus cerasus L. genotypes in Feketić region

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Radičević Sanja

2012-01-01

Full Text Available Autochthonous genotypes of fruit species are very important source of genetic variability and valuable material for breeding work. Fruit Research Institute-Čačak has a long tradition of studying autochthonous genotypes of temperate fruits sporadically spread and preserved in some localities in Serbia. Over 2005-2006, the following properties of nine autochthonous sour cherry genotypes grown in Feketic region were investigated: flowering and ripening time, pomological properties, biochemical composition of fruits and field resistance to causal agents of cherry diseases - cherry leaf spot (Blumeriella jaapii (Rehm. v. Arx., shot-hole (Clasterosporium carpophilum (Lév. Aderh. and brown rot (Monilinia laxa /Ader et Ruhl./ Honey ex Whetz.. The genotypes were tested for the presence of Prune dwarf virus and Prunus necrotic ring spot virus. In majority of genotypes fruits were large, with exceptional organoleptical properties, whereas ripening time was in the first ten or twenty days of June. The highest fruit weight was observed in F-1 genotype (8.1 g. The highest soluble solids and total sugars content were found in F- 4 genotype (17.60% and 14.25%, respectively. As for field resistance to causal agents of diseases and good pomo-technological properties, F-1, F-2, F-3, F-7 and F-8 genotypes were singled out. [Projekat Ministarstva nauke Republike Srbije, br. TR31064

Mutants of Venturia ineaqualis (Cook) Wint. apple scar resistant to fungicides

International Nuclear Information System (INIS)

Bedianashvili, Ts.V.; D'yakov, Yu.T.

1987-01-01

Mutants of apple scab resistant to zineb and bayleton fungicides have been obtained upon action of UV irradiation and nitrosome-thylurea. Using tetrade analysis, two zineb resistence genes have been found. The mutations are pleiotropic and lead to increase in resistance to other fungicides, decrease in growth rate on artificial media, increase in spore size, sporulation, and aggressiveness, decrease in competitiveness at in vitro growth. The resistance is supposed to be determined by decrease in membrane permeability for fungicides

Triomicrus Sharp of Eastern China (Coleoptera: Staphylinidae: Pselaphinae).

Science.gov (United States)

Shen, Jia-Wei; Yin, Zi-Wei; Li, Li-Zhen

2015-08-31

Twelve species of the genus Triomicrus Sharp are here recognized in eastern China, with eleven of them described as new: T. Inaequalis Shen & Yin, sp. n. and T. mirus Shen & Yin, sp. n. from Anhui, T. abhorridus Shen & Yin, sp. n., T. aculeus Shen & Yin, sp. n., T. damingensis Shen & Yin, sp. n., T. frondosus Shen & Yin, sp. n., T. gutianensis Shen & Yin, sp. n. and T. tibialis Shen & Yin, sp. n. from Zhejiang, T. anfractus Shen & Yin, sp. n. from Anhui and Zhejiang, T. Hamus Shen & Yin, sp. n. from Jiangxi, and T. contus Shen & Yin, sp. n. from Jiangxi and Zhejiang. New distributional data for T. rougemonti Löbl, Kurbatov &Nomura is given. A key for the identification of the Triomicrus species in eastern China is presented.

Promising sour cherry hybrids (Prunus cerasus L. developed at Fruit Research Institute Čačak

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Radičević Sanja

2010-01-01

Full Text Available At Fruit Research Institute in Čačak, major objectives of the work on breeding new sour cherry (Prunus cerasus L. cultivars are high cropping, large, high-quality fruits and resistance to causal agents of diseases and pests. As a result of the planned hybridization, more than 10,000 hybrid seedlings have been developed from about 40 cultivars within more than 110 parental combinations, among which are 'Čačanski rubin' ('Shasse Morello' x 'Köröser Weichsel' and 'Šumadinka' ('Köröser Weichsel' x 'Heimanns Konserven Weichsel' which have been named and released. Ten-year study of 11 hybrids, selected from the population of about 3,000 hybrid seedlings, gave four hybrids which have been singled out as elite (III/23, III/31, II/40 i XII/57. These hybrids are currently under procedure of being released as new cultivars. The paper presents two-year results of the study of ripening time, pomological properties, biochemical composition of fruits, and field resistance to causal agents of diseases and pests attacking the above named genotypes which were compared to standard cultivar 'Heimanns Konserven Weichsel'. In the studied hybrids, fruit weight, soluble solids content and sugars content were higher than in standard cultivar. In addition, they exhibit substantial field resistance to causal agents of brown rot (Monilinia laxa /Ader et Ruhl./ Honey ex Whetz., cherry leaf spot (Blumeriella jaapii (Rehm. v. Arx., shot-hole (Clasterosporium carpophilum (Lév. Aderh. and cherry fruit fly (Rhagoletis cerasi L. attack.

Genera of phytopathogenic fungi: GOPHY 1

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Y. Marin-Felix

2017-03-01

Full Text Available Genera of Phytopathogenic Fungi (GOPHY is introduced as a new series of publications in order to provide a stable platform for the taxonomy of phytopathogenic fungi. This first paper focuses on 21 genera of phytopathogenic fungi: Bipolaris, Boeremia, Calonectria, Ceratocystis, Cladosporium, Colletotrichum, Coniella, Curvularia, Monilinia, Neofabraea, Neofusicoccum, Pilidium, Pleiochaeta, Plenodomus, Protostegia, Pseudopyricularia, Puccinia, Saccharata, Thyrostroma, Venturia and Wilsonomyces. For each genus, a morphological description and information about its pathology, distribution, hosts and disease symptoms are provided. In addition, this information is linked to primary and secondary DNA barcodes of the presently accepted species, and relevant literature. Moreover, several novelties are introduced, i.e. new genera, species and combinations, and neo-, lecto- and epitypes designated to provide a stable taxonomy. This first paper includes one new genus, 26 new species, ten new combinations, and four typifications of older names.

Capillary Electrophoresis Single-Strand Conformational Polymorphisms as a Method to Differentiate Algal Species

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Alice Jernigan

2015-01-01

Full Text Available Capillary electrophoresis single-strand conformational polymorphism (CE-SSCP was explored as a fast and inexpensive method to differentiate both prokaryotic (blue-green and eukaryotic (green and brown algae. A selection of two blue-green algae (Nostoc muscorum and Anabaena inaequalis, five green algae (Chlorella vulgaris, Oedogonium foveolatum, Mougeotia sp., Scenedesmus quadricauda, and Ulothrix fimbriata, and one brown algae (Ectocarpus sp. were examined and CE-SSCP electropherogram “fingerprints” were compared to each other for two variable regions of either the 16S or 18S rDNA gene. The electropherogram patterns were remarkably stable and consistent for each particular species. The patterns were unique to each species, although some common features were observed between the different types of algae. CE-SSCP could be a useful method for monitoring changes in an algae species over time as potential shifts in species occurred.

Reconstitution of Vanadium Haloperoxidase's Catalytic Activity by Boric Acid-Towards a Potential Biocatalytic Role of Boron.

Science.gov (United States)

Natalio, Filipe; Wiese, Stefanie; Brandt, Wolfgang; Wessjohann, Ludger

2017-04-11

Boron's unusual properties inspired major advances in chemistry. In nature, the existence and importance of boron has been fairly explored (e.g. bacterial signaling, plant development) but its role as biological catalyst was never reported. Here, we show that boric acid [B(OH) 3 ] can restore chloroperoxidase activity of Curvularia inaequalis recombinant apo-haloperoxidase's (HPO) in the presence of hydrogen peroxide and chloride ions. Molecular modeling and semi-empirical PM7 calculations support a thermodynamically highly favored (bio)catalytic mechanism similarly to vanadium haloperoxidases (V-HPO) in which [B(OH) 3 ] is assumedly located in apo-HPO's active site and a monoperoxyborate [B(OH) 3 (OOH) - ] intermediate is formed and stabilized by interaction with specific active site amino acids leading ultimately to the formation of HOCl. Thus, B(OH) 3 -HPO provides the first evidence towards the future exploitation of boron's role in biological systems. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phytochemical Analysis and Antifungal Activity of Extracts from Leaves and Fruit Residues of Brazilian Savanna Plants Aiming Its Use as Safe Fungicides.

Science.gov (United States)

Breda, Caroline Alves; Gasperini, Alessandra Marcon; Garcia, Vera Lucia; Monteiro, Karin Maia; Bataglion, Giovana Anceski; Eberlin, Marcos Nogueira; Duarte, Marta Cristina Teixeira

2016-08-01

The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity. In this study, ethanolic extracts from leaves and fruit residues (peel and seeds) of three Brazilian savanna species (Acrocomia aculeata, Campomanesia adamantium and Caryocar brasiliense) were evaluated against phytopathogenic fungi. Additionally, the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated. Extracts from C. brasiliense (pequi) peel and leaves were active against Alternaria alternata, Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 µg/mL. When incorporated in solid media, these extracts extended the lag phase of A. alternata and A. solani and reduced the growth rate of A. solani. Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid, quinic acid, ellagic acid, glucogalin and corilagin. The oral acute toxicity was relatively low, being considered safe for use as a potential natural fungicide.

Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis.

Science.gov (United States)

Amat, Isabelle; van Alphen, Jacques J M; Kacelnik, Alex; Desouhant, Emmanuel; Bernstein, Carlos

2017-01-01

Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores) where host outbreaks offer periods when egg-load is the main constraint on reproductive output. We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen's d value; Cohen, 1988). Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

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Isabelle Amat

2017-09-01

Full Text Available Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores where host outbreaks offer periods when egg-load is the main constraint on reproductive output. Methods We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen’s d value; Cohen, 1988. Results Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Discussion Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

Host switching in a generalist parasitoid: contrasting transient and transgenerational costs associated with novel and original host species.

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Jones, Thomas S; Bilton, Adam R; Mak, Lorraine; Sait, Steven M

2015-01-01

Parasitoids face challenges by switching between host species that influence survival and fitness, determine their role in structuring communities, influence species invasions, and affect their importance as biocontrol agents. In the generalist parasitoid, Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae), we investigated the costs in encapsulation, survival, and body size on juveniles when adult parasitoids switched from their original host, Plodia interpunctella (Hübner) (Lepidotera, Pyralidae) to a novel host, Ephestia kuehniella (Zeller) (Lepidoptera, Pyralidae), over multiple generations. Switching had an initial survival cost for juvenile parasitoids in the novel host, but increased survival occurred within two generations. Conversely, mortality in the original host increased. Body size, a proxy for fecundity, also increased with the number of generations in the novel host species, reflecting adaptation or maternal effects due to the larger size of the novel host, and therefore greater resources available to the developing parasitoid. Switching to a novel host appears to have initial costs for a parasitoid, even when the novel host may be better quality, but the costs rapidly diminish. We predict that the net cost of switching to a novel host for parasitoids will be complex and will depend on the initial reduction in fitness from parasitizing a novel host versus local adaptations against parasitoids in the original host.

Host and food searching in a parasitic wasp Venturia canescens: a trade-off between current and future reproduction?

NARCIS (Netherlands)

Desouhant, E.; Driessen, G.J.J.; Amat, I.; Bernstein, C.

2005-01-01

Whether to invest in current or future reproduction is an important trade-off in life history evolution. For insect parasitoids, this trade-off is determined, among other factors, by the decision whether to search for hosts (immediate gain of fitness) or food (delayed fitness gains). Although host

Honey Bee Viruses in Wild Bees: Viral Prevalence, Loads, and Experimental Inoculation

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Dolezal, Adam G.; Hendrix, Stephen D.; Scavo, Nicole A.; Carrillo-Tripp, Jimena; Harris, Mary A.; Wheelock, M. Joseph; O’Neal, Matthew E.; Toth, Amy L.

2016-01-01

Evidence of inter-species pathogen transmission from managed to wild bees has sparked concern that emerging diseases could be causing or exacerbating wild bee declines. While some pathogens, like RNA viruses, have been found in pollen and wild bees, the threat these viruses pose to wild bees is largely unknown. Here, we tested 169 bees, representing 4 families and 8 genera, for five common honey bee (Apis mellifera) viruses, finding that more than 80% of wild bees harbored at least one virus. We also quantified virus titers in these bees, providing, for the first time, an assessment of viral load in a broad spectrum of wild bees. Although virus detection was very common, virus levels in the wild bees were minimal—similar to or lower than foraging honey bees and substantially lower than honey bees collected from hives. Furthermore, when we experimentally inoculated adults of two different bee species (Megachile rotundata and Colletes inaequalis) with a mixture of common viruses that is lethal to honey bees, we saw no effect on short term survival. Overall, we found that honey bee RNA viruses can be commonly detected at low levels in many wild bee species, but we found no evidence that these pathogens cause elevated short-term mortality effects. However, more work on these viruses is greatly needed to assess effects on additional bee species and life stages. PMID:27832169

Honey Bee Viruses in Wild Bees: Viral Prevalence, Loads, and Experimental Inoculation.

Science.gov (United States)

Dolezal, Adam G; Hendrix, Stephen D; Scavo, Nicole A; Carrillo-Tripp, Jimena; Harris, Mary A; Wheelock, M Joseph; O'Neal, Matthew E; Toth, Amy L

2016-01-01

Evidence of inter-species pathogen transmission from managed to wild bees has sparked concern that emerging diseases could be causing or exacerbating wild bee declines. While some pathogens, like RNA viruses, have been found in pollen and wild bees, the threat these viruses pose to wild bees is largely unknown. Here, we tested 169 bees, representing 4 families and 8 genera, for five common honey bee (Apis mellifera) viruses, finding that more than 80% of wild bees harbored at least one virus. We also quantified virus titers in these bees, providing, for the first time, an assessment of viral load in a broad spectrum of wild bees. Although virus detection was very common, virus levels in the wild bees were minimal-similar to or lower than foraging honey bees and substantially lower than honey bees collected from hives. Furthermore, when we experimentally inoculated adults of two different bee species (Megachile rotundata and Colletes inaequalis) with a mixture of common viruses that is lethal to honey bees, we saw no effect on short term survival. Overall, we found that honey bee RNA viruses can be commonly detected at low levels in many wild bee species, but we found no evidence that these pathogens cause elevated short-term mortality effects. However, more work on these viruses is greatly needed to assess effects on additional bee species and life stages.

Isolation and identification of fungi from a meju contaminated with aflatoxins.

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Jung, Yu Jung; Chung, Soo Hyun; Lee, Hyo Ku; Chun, Hyang Sook; Hong, Seung Beom

2012-12-01

A home-made meju sample contaminated naturally with aflatoxins was used for isolation of fungal strains. Overall, 230 fungal isolates were obtained on dichloran rosebengal chloramphenicol (DRBC) and dichloran 18% glycerol (DG18) agar plates. Morphological characteristics and molecular analysis of a partial beta-tubulin gene and the internal transcribed spacer (ITS) of rDNA were used for the identification of the isolates. The fungal isolates were divided into 7 genera: Aspergillus, Eurotium, Penicillium, Eupenicillium, Mucor, Lichtheimia, and Curvularia. Three strains from 56 isolates of the A. oryzae/flavus group were found to be aflatoxigenic A. flavus, by the presence of the aflatoxin biosynthesis genes and confirmatory aflatoxin production by high-performance liquid chromatography (HPLC). The predominant isolate from DRBC plates was A. oryzae (42 strains, 36.2%), whereas that from DG18 was A. candidus (61 strains, 53.5%). Out of the 230 isolates, the most common species was A. candidus (34.3%) followed by A. oryzae (22.2%), Mucor circinelloides (13.0%), P. polonicum (10.0%), A. tubingensis (4.8%), and L. ramosa (3.5%). A. flavus and E. chevalieri presented occurrence levels of 2.2%, respectively. The remaining isolates of A. unguis, P. oxalicum, Eupenicillium cinnamopurpureum, A. acidus, E. rubrum, P. chrysogenum, M. racemosus, and C. inaequalis had lower occurrence levels of < 2.0%.

Does kin recognition and sib-mating avoidance limit the risk of genetic incompatibility in a parasitic wasp?

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Marie Metzger

2010-10-01

Full Text Available When some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination, and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness.In this paper, we tested the hypothesis of genetic incompatibility avoidance by investigating sib-mating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In "no-choice" tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males.Our results are compatible with the genetic incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a "self-referent phenotype matching" mechanism.

Intraspecific competition: the role of lags between attack and death in host-parasitoid interactions.

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Cameron, T C; Metcalfe, D; Beckerman, A P; Sait, S M

2007-05-01

Many natural enemies do not immediately kill their host, and the lag this creates between attack and host death results in mixed populations of uninfected and infected hosts. Both competition and parasitism are known to be major structuring forces in ecological communities; however, surprisingly little is known about how the competitive nature of infected hosts could affect the survival and dynamics of remaining uninfected host populations. Using a laboratory system comprising the Indian meal moth, Plodia interpunctella, and a solitary koinobiont parasitoid, Venturia canescens, we address this question by conducting replicated competition experiments between the unparasitized and parasitized classes of host larvae. For varying proportions of parasitized host larvae and competitor densities, we consider the effects of competition within (intraclass) and between (interclass) unparasitized and parasitized larvae on the survival, development time, and size of adult moths and parasitoid wasps. The greatest effects were on survival: increased competitor densities reduced survival of both parasitized and unparasitized larvae. However, unparasitized larvae survival, but not parasitized larvae survival, was reduced by increasing interclass competition. To our knowledge, this is the first experimental demonstration of the competitive superiority of parasitized over unparasitized hosts for limiting resources. We discuss possible mechanisms for this phenomenon, why it may have evolved, and its possible influence on the stability of host-parasite dynamics.

The alpha-amylase inhibitor acarbose does not affect the parasitoid Venturia canescens when incorporated into the diet of its host Ephestia kuehniella

Czech Academy of Sciences Publication Activity Database

Kaufnerová, J.; Münzbergová, Zuzana; Jarošík, Vojtěch; Hubert, J.

2007-01-01

Roč. 124, č. 1 (2007), s. 17-25 ISSN 0013-8703 R&D Projects: GA ČR(CZ) GA522/04/1286; GA MŠk(CZ) LC06073 Grant - others:GA MŠk(CZ) 1P04OC842.20 Program:1P Institutional research plan: CEZ:AV0Z60050516 Keywords : Ichneumonidae * Lepidoptera * Pyralidae Subject RIV: EF - Botanics Impact factor: 1.483, year: 2007

MENTIMUN(Cucumis Sativus L DI DESA TIRTA MULYA KECAMATAN MAKARTI JAYA KABUPATEN BANYUASIN II

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Irham Falahudin

2015-08-01

Full Text Available Cucumber plants (Cucumis sativus L. that includes or creeping vines and is one type of vegetable-fruit of the gourd family labuan (Cucurbitaceae that has been popular throughout the world and favored from Asia. Cucumber cultivation in Indonesia, found almost in every region, ranging from lowland to highland hot climate (tropical and moderate. One animal that has an abundant amount in cucumber plants are insects. This study aims to know the different types of species that exist on the Order Coleoptera cucumber farm in the village of Tirta Mulya District of makarti Jaya Banyuasin II and determine the role of the Order Coleoptera insects on cucumber plantations in the village of Tirta Mulya District of makarti Jaya Banyuasin II. This is a qualitative study conducted in October-November 2014 held in Cucumber Plants in the village of Tirta Mulya District of makarti Jaya Banyuasin II. Catching insects done using transect method and pitfall traps such as sweeping the net, pit fall traps and light traps, results in identification in the laboratory penelitanya UIN Raden Fatah Palembang. The results of this study indicate that insects are caught in a cucumber plantation obtained as many as 113 individual 3 families and 7 species. Insects which dominates in the village of Tirta Mulya District of makarti Jaya Banyuasin II is Cocinella repanda, Curinus coeruleus, Coelophora inaequalis, and Aulacophora similis, and insects that have the fewest number is Micraspis discolor, Micraspis vincta and Oryctes rhinoceros. The role of the Order Coleoptera Insects in general predators of the family Coccinellidae to eradicate mites while the family Chrysomelidae Scarabacidae and are pests that attack on cucumber plants that can cause death.

Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

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López-Uribe, Margarita M; Morreale, Stephen J; Santiago, Christine K; Danforth, Bryan N

2015-01-01

Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing

Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

Directory of Open Access Journals (Sweden)

Margarita M López-Uribe

Full Text Available Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011. Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting

The genomic features of parasitism, Polyembryony and immune evasion in the endoparasitic wasp Macrocentrus cingulum.

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Yin, Chuanlin; Li, Meizhen; Hu, Jian; Lang, Kun; Chen, Qiming; Liu, Jinding; Guo, Dianhao; He, Kang; Dong, Yipei; Luo, Jiapeng; Song, Zhenkun; Walters, James R; Zhang, Wenqing; Li, Fei; Chen, Xuexin

2018-05-30

Parasitoid wasps are well-known natural enemies of major agricultural pests and arthropod borne diseases. The parasitoid wasp Macrocentrus cingulum (Hymenoptera: Braconidae) has been widely used to control the notorious insect pests Ostrinia furnacalis (Asian Corn Borer) and O. nubilalis (European corn borer). One striking phenomenon exhibited by M. cingulum is polyembryony, the formation of multiple genetically identical offspring from a single zygote. Moreover, M. cingulum employs a passive parasitic strategy by preventing the host's immune system from recognizing the embryo as a foreign body. Thus, the embryos evade the host's immune system and are not encapsulated by host hemocytes. Unfortunately, the mechanism of both polyembryony and immune evasion remains largely unknown. We report the genome of the parasitoid wasp M. cingulum. Comparative genomics analysis of M. cingulum and other 11 insects were conducted, finding some gene families with apparent expansion or contraction which might be linked to the parasitic behaviors or polyembryony of M. cingulum. Moreover, we present the evidence that the microRNA miR-14b regulates the polyembryonic development of M. cingulum by targeting the c-Myc Promoter-binding Protein 1 (MBP-1), histone-lysine N-methyltransferase 2E (KMT2E) and segmentation protein Runt. In addition, Hemomucin, an O-glycosylated transmembrane protein, protects the endoparasitoid wasp larvae from being encapsulated by host hemocytes. Motif and domain analysis showed that only the hemomucin in two endoparasitoids, M. cingulum and Venturia canescens, possessing the ability of passive immune evasion has intact mucin domain and similar O-glycosylation patterns, indicating that the hemomucin is a key factor modulating the immune evasion. The microRNA miR-14b participates in the regulation of polyembryonic development, and the O-glycosylation of the mucin domain in the hemomucin confers the passive immune evasion in this wasp. These key findings provide

The Use of Copper Pesticides in Germany and the Search for Minimization and Replacement Strategies

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Stefan Kuehne

2017-02-01

Full Text Available Copper pesticides used to control fungal and bacterial diseases such as grapes downy mildew (Plasmopara viticola, downy mildew of hops (Pseudoperonospora humili, apple scab (Venturia spp., fireblight (Erwinia amylovora and potato late blight (Phytophthora infestans, play an important role in plant protection. In a 2013 survey of copper application in Germany we found, that while the amounts of copper used per hectare in conventional grape (0.8 kg ha−1, hop (1.7 kg ha−1 and potato-farming (0.8 kg ha−1 were well below those used in organic farming (2.3, 2.6 and 1.4 kg ha−1, respectively, they were nearly identical to those used in apple growing (1.4 kg ha−1. Due to the smaller farming area, only 24% (26.5 tonnes of the total amount of copper was applied in organic farming compared to 76% (84.8 tonnes in conventional farming. Since 2001, the Federal Agency for Agriculture and Food (BLE promoted a copper research and minimization strategy which was funded with a total of C10.2 million. Our status quo analysis of research in this field shows that some progress is being made concerning alternative compounds, resistant varieties and decision support systems. However, it also shows that new approaches are not yet able to replace copper pesticides completely, especially in organic farming. In integrated pest management, copper preparations are important for the necessary active substance rotation and successful resistance management. The availability of such products is often essential for organic grapes, hops and fruit production and for extending the organic farming of these crops. We conclude that the complete elimination of copper pesticides is not yet practicable in organic farming as the production of several organic crops would become unprofitable and may lead to organic farmers reverting to conventional production. Several existing copper reduction strategies were, however, identified, and some, like modified forecast models adapted to

A revision of the New Zealand weevil genus Irenimus Pascoe, 1876 (Coleoptera: Curculionidae: Entiminae).

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Brown, Samuel D J

2017-05-08

The taxonomy of the New Zealand weevil genus Irenimus Pascoe, 1876 is revised, resulting in a narrower concept of the genus than has been considered in recent decades. In total, the genus now contains only seven species. In addition to the type species, I. parilis Pascoe, 1876, the genus contains I. duplex (Broun, 1904) and five newly described species: I. aniptus new species (type locality, Oamaru, DN), I. crinitus new species (type locality, Hakataramea Valley, SC), I. minimus new species (type locality, Alexandra, CO), I. stichus new species (type locality, Tekapo, MK) and I. thoracicus new species (type locality, Oamaru, DN). The genus Chalepistes new genus is established to contain the majority of species previously described in the genus Catoptes Schönherr, 1842, but also including species described in Brachyolus White, 1846; Irenimus Pascoe, 1876; Inophloeus Pascoe, 1875; and Nicaeana Pascoe, 1877. A total of 27 valid described species are new combinations with Chalepistes: C. aequalis (Broun, 1895) (from Irenimus), C. albosparsus (Broun, 1917) (from Irenimus), C. apicalis (Broun, 1923) (from Catoptes), C. asperatus (Broun, 1914) (from Brachyolus), C. compressus (Broun, 1880) (from Irenimus), C. costifer (Broun, 1886) (from Inophloeus), C. curvus (Barratt & Kuschel, 1996) (from Irenimus), C. dehiscens (Broun, 1917) (from Catoptes), C. dugdalei (Barratt & Kuschel, 1996) (from Irenimus), C. egens (Broun, 1904) (from Irenimus), C. inaequalis (Sharp, 1886) (from Brachyolus), C. instabilis (Marshall, 1931) (from Catoptes), C. latipennis (Broun, 1893) (from Catoptes), C. limbatus (Broun, 1909) (from Catoptes), C. lobatus (Broun, 1921) (from Catoptes), C. patricki (Barratt & Kuschel, 1996) (from Irenimus), C. pensus (Broun, 1914) (from Inophloeus), C. placidus (Broun, 1914) (from Nicaeana), C. posticalis (Broun, 1893) (from Irenimus), C. rhesus (Pascoe, 1875) (from Inophloeus), C. rubidus (Broun, 1881) (from Inophloeus), C. similis (Barratt & Kuschel, 1996) (from