Richtlinien der Verbände des ökologischen Landbaus zum Vorratsschutz

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

Development of protocols for detection of Colletotrichum acutatum and monitoring of strawberry anthracnose using real-time PCR

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

A systematic review of the literature reveals trends and gaps in integrated pest management studies conducted in the United States

Integrated pest management (IPM) is a broad‐based approach for addressing pests that negatively affect human and environmental health and economic profitability. Weeds, insects and disease‐causing pathogens (diseases) are the pests most often associated with IPM. A systematic review, widely used in other scientific disciplines, was employed to determine the most commonly studied IPM topics and summarize the reasons for these trends and the gaps. In a field synopsis of the literature, 1679 relevant published papers were identified and categorized into one of the following five broad areas: IPM and organic (organic), climate change and pests (climate), rural and urban IPM (rural and urban), next‐generation education (education) and advanced production systems (technology). Papers were examined in greater detail for at least one of the three main pests in a systematic review. A majority (85%) of IPM papers have been in the area of rural and urban IPM, primarily addressing agriculture (78%). Professionals, landowners and the general public were the focus of a majority (95%) of IPM papers on education. Technology is an increasing area of focus in the literature. Over the past 40 years, IPM papers have primarily (75%) addressed insects and been limited mostly to rural and urban settings. Climate change, technology and education specific to pest management studies are increasingly being published and will help broaden the focus that could result in increased adoption and development of IPM. © 2017 Society of Chemical Industry     

Thermal and hormonal regulation of the dormancy–germination transition in Amaranthus tuberculatus seeds

The transition from seed dormancy to germination is a multi‐step process. However, distinguishing between physiological processes involved in seed dormancy alleviation and those involved in germination has been difficult. We studied the seed dormancy alleviation process in Amaranthus tuberculatus, an important weed species in midwestern USA. Using three A. tuberculatus biotypes that differ in dormancy level, it was determined that stratification reduced seed dormancy from a high to a low level. Temperature alternation alleviated low seed dormancy and triggered germination. Exogenously applied abscisic acid (ABA) and gibberellic acid (GA) had no effect on seeds with high dormancy. However, ABA and paclobutrazol (a GA biosynthesis inhibitor) significantly reduced germination of seeds with low dormancy. Hormones could not replace the effects of stratification or temperature alternation on dormancy alleviation. Based on our results, we propose a seed dormancy–germination transition model in which the dormancy of A. tuberculatus seeds is progressively reduced from a high to a low level; but environmental conditions (i.e. stratification) can accelerate the dormancy alleviation process. Under low dormancy levels, the seed is more sensitive to environmental cues that are responsible for removing dormancy and triggering germination (i.e. temperature alternation). Finally, ABA and GA regulation occurs primarily during the final transition from low dormancy to germination rather than the alleviation of high dormancy.     

Description ofPauesia (Pauesia)anatolica (Hymenoptera: Braconidae, Aphidiinae) sp. nov., a parasitoid of the cedar aphidCinara cedri

The first parasitoid species reared from a population of the cedar aphid,Cinara cedri Mimeur, 1935 (Hemiptera: Aphididae), from the peninsula of Anatolia in Turkey is described.Pauesia anatolica (Hymenoptera: Braconidae, Aphidiinae) is closely related to some species of thelaricis group ofPauesia from which it differs in the number of antenomers, the propodeum and features of the female genitalia. Its potential use as a natural enemy in areas where the aphid has been introduced is discussed. http://www.phytoparasitica.org posting Aug. 28, 2005.     

Current statistical issues in Weed Research

The correct design of experimental studies, the selection of the appropriate statistical analysis of data and the efficient presentation of results are key to the good conduct and communication of science. The last Guidance for the use and presentation of statistics in Weed Research was published in 1988. Since then, there have been developments in both the scope of research covered by the journal and in the statistical techniques available. This paper addresses the changes in statistics and provides a reference work that will aid researchers in the design and analysis of their work. It will also provide guidance for editors and reviewers. The paper is organised into sections, which will aid the selection of relevant paragraphs, as we recognise that particular approaches require particular statistical analysis. It also uses examples, questions and checklists, so that non-specialists can work towards the correct approach. Statistics can be complex, so knowing when to seek specialist advice is important. The structure and layout of this contribution should help weed scientists, but it cannot provide a comprehensive guide to every technique. Therefore, we provide references to further reading. We would like to reinforce the idea that statistical methods are not a set of recipes whose mindless application is required by convention; each experiment or study may involve subtleties that these guidelines cannot cover. Nevertheless, we anticipate that this paper will help weed scientists in their initial designs for research, in the analysis of data and in the presentation of results for publication.     

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

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

Plant Viruses Transmitted by Whiteflies

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

Electrophoretic and serological comparisons of pathogenesis-related (b) proteins from different plant species

Preparations of pathogenesis-related (b) proteins (PRs) from differentNicotiana species, tomato,Gynura aurantiaca, bean, and cowpea were compared to each other and to bean chitinase and a constitutive apple agglutinin by electrophoresis in polyacrylamide gels both in the absence and in the presence of SDS, and by serological double diffusion analysis using antisera against tobacco PRs and bean chitinase. PRs from different plant genera displayed a similar but not identical range of relative mobilities in both native and SDS gels, whereas bean chitinase and apple agglutinin were clearly different. None of the antisera reacted with any of the PR preparations from plant genera other than the one from which the antigen(s) had been derived. Whilst PRs within the genusNicotiana are serologically related and can be identical, PRs from different plant genera seem to be sufficiently different to be considered as genus-specific.