Über eine Besonderheit in der Entwicklung der Fundatrigenien von Myzodes persicae Sulzer im Jahre 1952 in NW-Deutschland     

Dr. Wolfgang Rönnebeck 《Journal of pest science》1953,26(3):35-37

Ohne Zusammenfassung  相似文献   

Untersuchungen zur Biologie,Morphologie und Verbreitung von Herpotrichia parasitica (Hartig) E. Rostrup (vormals Trichosphaeria parasitica Hartig)     

K. Von Freyur 《Forest Pathology》1976,6(4):222-238

Studies on the biology, morphology and spread of Herpotrichia parasitica (Hartig) E. Rostrup (formerly Trichosphaeria parasitica Hartig). Part II: Method of infection, hosts and pure culture. H. parasitica (Hartig) E. Rostrup (conidial stage Pyrenocbacta parasitica Preyer et van der Aa) overwinters by means of both types of fruit bodies on the needles of hosts but also by means of mycelium which grows along the under sides of shoots during the growing season, reaches the buds and penetrates under the outer bud scales. Spread of the fungus is thus independent of spores. As well as Abies alba, other silver firs are attacked. Contact infection with mycelium on Picea sitchensis was also observed. Studies with pycnospores showed that germination on needles of host species varied with humidity. In culture the fungus grew best on 2 % malt agar, pH 6 at 21°C.  相似文献   

Bemerkungen zur Lebensweise und Bekämpfung des KieferntriebwicklersEvetria (Rhyacionia) buoliana Schiff     

Wolfgang Wachtendorf 《Journal of pest science》1959,32(4):59-61

Zusammenfassung In den Jahren 1950 bis 1955 trat in Bayern der KieferntriebwicklerEvetria (Rhyacionia) buoliana Schiff. in Massenvermehrung. Innerhalb der bayrischen Kieferngebiete lagen die Hauptschadensstellen sämtlich auf armen Sandoder Schotterböden. Bei mehrjährigen Angriffen wurde der Höhenzuwachs ganz ausgeschaltet, wobei kennzeichnende Wuchsformen entstehen. Zur Beendigung der Gradation trugen die Winter 1954/55 und 1955/56 mit ihren tiefen Temperaturen durch stark erhöhte Raupensterblichkeit das meiste bei, Parasitenbefall trat demgegenüber stark zurück.Die Bekämpfungsversuche wurden mit dem innertherapeutischen Präparat Systox begonnen, später wurde das weniger giftige Metasystox dazugenommen. Der Phosphorsäureester Dipterex-Emulsion, kein echtes innertherapeutisches Insektizid, zeichnete sich dennoch durch beträchtliches Eindringvermögen aus und zeigte großte Toxizität gegenüber den Wicklerraupen, so daß er unter den drei untersuchten Mitteln am besten wirkte. Die erforderlichen hohen Konzentrationen lassen die Systox-Spritzbrühe als so bedenklich erscheinen, daß dieses Präparat in diesem Falle für die Praxis nicht empfohlen werden kann. Bei Metasystox oder Dipterex bestehen diese Bedenken nicht.Nachdem die ersten Versuche bei den üblichen Konzentrationen keine befriedigenden Ergebnisse brachten, wurden die Konzentrationen auf das 10–20fache (0,5% bis 1%) erhöht. Damit ließen sich gute Erfolge erzielen. wenn auch nicht immer restlose Abtötung erreicht wurde. Falsch wäre es jedoch, an den Mittelkosten sparen zu wollen, da damit der Erfolg stark in Frage gestellt wird. Phytotoxische Erscheinungen traten in keinem Falle auf.Für eine erfolgreiche Bekämpfung kommt nur der Zeitraum von August bis November in Frage. Eine Frü hjahrsbehandlung ist mit einer beträchtlichen Wirkungseinbuße verbunden, so daß sie nicht empfohlen werden kann.Die Verwendung von Dieselöl als Trägermittel der Insektizide erwies sich — bei sehr guter Wirkung — wegen mehrfachen Pflanzenschädigungen als ungeeignet.Für die gewährte Unterstützung bei dieser Untersuchung sei den Amtsvorständen der Forstämter Amberg, Geisenfeld, Neuhaus/P., Schnaittenbach und Selb an dieser Stelle herzlich gedankt. Die verwendeten Insektizide stellten die Farbenfabriken Bayer, Leverkusen freundlichst zur Verfügung, wofür ebenfalls gedankt sei.  相似文献   

Effect of parent genotype on somatic embryogenesis in Scots pine (Pinus sylvestris)     

Niskanen AM  Lu J  Seitz S  Keinonen K  Von Weissenberg K  Pappinen A 《Tree physiology》2004,24(11):1259-1265

Controlled crosses of seven Scots pine (Pinus sylvestris L.) trees produced 49 families that included both reciprocals and selfings. Embryogenic cultures were initiated from immature megagametophytes and after 6 months in maintenance culture, mature somatic embryos were produced from the surviving 166 lines. The effect of parent genotypes on the cultures was evaluated at initiation of the tissue culture period, after 6 months in maintenance culture and at embryo maturation. The effect of the maternal parent was most pronounced at culture initiation. After 6 months in tissue culture, the maternal effect had decreased and the effects of both parents were significant. By the somatic embryo maturation stage, the maternal effect was still considerable but the paternal effect was no longer detectable. There was little correlation between the ranking of mothers and fathers, indicating that the maternal effect was caused by factors other than the paternal effect. No mother x father interaction was found, indicating that mothers successful at initiation and after 6 months in tissue culture, pollinated by any of the successful fathers, produced somatic lines and mature somatic embryos.  相似文献   

Rosellinia minor (Höhn.) Francis in Christbaumkulturen     

Von T. Cech 《Forest Pathology》1990,20(2):113-117

Damages in Christmas tree-plantations of Norway spruce by Rosellinia minor (Höhn.) Francis. In a plantation of Christmas trees of Norway spruce in the valley of Rhine (Vorarlberg, Austria) an epidemy of Rosellinia minor (Höhn.) Francis occurred in 1987 and 1988. 10 years old trees were totally affected by the fungus. Differences in fruiting-structures between R. minor, R. herpotrichoides (Hept. and Davids.) and R. aquila (Fr.) de Not. are discussed.  相似文献   

Quantitative und qualitative Totholzerfassung in Buchenwirtschaftswäldern     

M. Von Erdmann  H. Wilke 《European Journal of Forest Research》1996,116(1-6):16-28

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Agroforestry in central,northern, and eastern Europe     

H. -J. Von Maydell 《Agroforestry Systems》1995,31(2):133-142

Integrated management of natural resources and the multiple use of trees and forests have prevailed in most European societies since prehistoric times. In the Middle Ages, expanding and intensified agriculture resulted in the separation of trees from agricultural fields. During the last century, with the introduction of sustainable and highly productive forest management, the goal of increased wood production has been achieved in most parts of central, northern, and eastern Europe. Today, agroforestry is not considered to be an important land-use option within the region; however, there are many practices that could rightfully be classified as agroforestry. These include tree/crop systems in which trees provide products and/or environmental benefits, and tree/animal systems in which animals are grazed in forests or open woodlands.The future seems to offer some prospects for agroforestry. Large areas, hitherto used for food production, are either marginally suited to agriculture, or will probably be taken out of production due to agricultural policy considerations. Agroforestry may, at least in part, offer alternatives for the use of such lands. The availability of (surplus) fertile soils, capital, and labor may provide incentives for site-adapted forms of agroforestry, including improved fallow management. The focus of such systems would be on maintenance of biodiversity in the landscape, environmental protection, recreation, and product diversification.There are numerous expectations as to what agroforestry might provide for the land holder and for society as a whole. These expectations should be carefully analyzed and evaluated prior to political decisions on future land use. The promotion of agroforestry requires overall investment; agroforestry does not happen by itself. A set of integrated actions — not isolated efforts — must be implemented if agroforestry is to become a successful land-use option.  相似文献   

Methylcarbamate inhibition of phenylcarbamate metabolism in soil   总被引：1，自引：0，他引：1  

D D Kaufman  P C Kearney  D W Von Endt  D E Miller 《Journal of agricultural and food chemistry》1970,18(3):513-519

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Evidence for formation of heterooligosaccharides by Lactobacillus sanfranciscensis during growth in wheat sourdough     

Tieking M  Kühnl W  Gänzle MG 《Journal of agricultural and food chemistry》2005,53(7):2456-2461

Lactobacillus sanfranciscensis is a key organism of the lactic microflora in traditional and industrial sourdough fermentations. In this paper we provide evidence for the formation of heterooligosaccharides (HeOS) by L. sanfranciscensis during growth in sourdough. To identify the HeOS based on HPAEC-PAD analysis, HeOS standards were synthesized by enzymatic reactions with L. sanfranciscensis levansucrase in a chemically defined system in the presence of raffinose, maltotriose, maltose, xylose, or arabinose as acceptor carbohydrates. The oligosaccharides known to originate from the corresponding acceptor reactions, 1(F)-beta-fructosylraffinose, 1(F)-beta-fructofuranosylmaltotriose, erlose (1(F)-beta-fructofuranosylmaltose), xylsucrose, 1(F)-beta-fructosylxylsucrose, and arabsucrose, were identified by HPAEC-PAD. Evidence for the formation of further tri-, tetra-, and pentasaccharides was provided. Wheat doughs with sucrose were fermented with L. sanfranciscesis TMW 1.392 or the isogenic, levansucrase-negative strain TMW 1.392Deltalev, and the analysis of dough extracts or invertase-treated dough extracts provided evidence for the formation of arabsucrose and erlose in sourdough in addition to 1-kestose and nystose.  相似文献   

Variations of soil phosphorus accumulation in Nanjing,China as affected by urban development     

Da‐Gang Yuan  Gan‐Lin Zhang  Zi‐Tong Gong  Wolfgang Burghardt 《植物养料与土壤学杂志》2007,170(2):244-249

Human activities can affect the biogeochemical cycling of phosphorus substantially. However, the relationship between P accumulation and urban development process is largely unknown. This study investigated the influence of urban development on the P accumulation in urban and suburban soils, using Nanjing (China) as a case. Based on its urban development history, Nanjing was divided into suburban and urban area, and the urban area was subdivided into urban north and urban south. Soil total P (TP) and available P (AP) of 578 samples from 68 pedons at different locations were measured. Thickness‐weighted mean P content of each pedon (P_w), P content of the surface soil layer (P_s), the highest P content of each pedon (P_h), and the lowest P content (P_l) of each pedon were selected as statistical indices. Compared with the background value, urban and suburban soils were enriched in P. The highest TP content was up to 11.14 g P kg^–1, and the highest AP content was up to 360 mg P kg^–1. However, analysis of variance (ANOVA) and multiple comparisons of P_w, P_s, P_h, P_l showed that urban south with longest residential history had the highest TP_w, TP_s TP_h, and AP_w, AP_l contents, and urbanizing suburban had the lowest TP_w and AP_w, AP_l contents. For both APs and AP_h, there was no significant difference between suburban and urban area. However, significant differences between urban south and urban north were observed. The results demonstrated that urban development process, including population quantity and level of urban infrastructure, could influence soil P accumulation and distribution in urban environment. A more detailed assessment is required to avoid the potential secondary eutrophication caused by excess P release from those anthropogenic high‐P soils.  相似文献