Beitrag zum Qualitäts- und Ertragspotenzial stress- und trockenheitstoleranter Sorten für Silo- und Energiemais bei optimaler Reife

Maize production trials carried out in eastern middle of Germany from 1999–2007 were used for statistical analysis of the optimum date for silage maize ripeness, quality and yield potential as well as choice of cultivar under drought conditions for silage and energy maize. The Silage maize Ripeness Index (the ratio of dry matter content of maize grains to dry matter content of stover) is more suitable for the determination of harvest date, yield maximum and silage maize quality as the dry matter content of the plant. The analysis is cheaper as well as not so material and time-consuming in comparison to the dry matter content of the silage maize of different hybrid maize populations and environments. Ensilage optimum and yield maximum correspond almost with the physiological ripeness of silage maize and are close to the grain dry matter content of 60 to 65%, to the dry matter content of stover under 24% and a ripeness index from 2,5 and higher. Only under these conditions it is possible to reach the optimal ripeness of 30 to 35% in the whole plant silage maize. In dependence on the Silage maize Ripeness Index (SRZ) parameters of silage and energy maize were created differential ripeness optimum, quality and yield potential. The aims of silage and energy maize are similar. The vitality of stover has a greater importance for energy maize. The Silage maize Ripeness Index (SRI) is, for whole plant maize, better than the Whole Plant Maize Ripeness Index (SRZ) for the choice of a hybrid in Germany. The dry matter content of grain in interaction with the dry matter of stover are better than dry matter content of the whole plant maize as ripeness indicator in the production of silage and energy maize for the harvesting time. SRI is also suitable for use as a standard in scientific trials and for better characteristic of cultivar types and environmental influence.     

Feldstudie zum Nachweis und zur Regulation von Weizenschädlingen und natürlichen Antagonisten

Wheat insect pests and the beneficial arthropod populations were assessed using sweep net across a large scale winter wheat field in Bad Lausick (Free State of Saxony, Germany) before and after insecticide applications. The insecticides used were Karate (pyrethroid), Biscaya (neonicotinoid) and NeemAzal T/S (botanical insecticide). The tested compounds were sprayed twice during the early season growth stage (Elongation- GS 32) and at the heading stage (GS 55), and their effects were evaluated on wheat insect pests. The side effects of these insecticides on associated natural enemies were also studied. Monitoring was conducted for 4 weeks after each treatment. Cereal aphids, thrips, leafhoppers, cereal leaf beetles, cereal bugs and also many natural enemies such as predators (lady beetles, lacewings, syrphids, dance flies and spiders) and parasitoids (parasitic wasps) were surveyed. The dose of these insecticides resulted in reductions of wheat insect and natural enemy populations and this reduction was corrected based on Abbott equation. The results showed that Karate is correlated with the highest percentage reduction (79.5 %) to wheat insect pests. Karate use also resulted in a percentage reduction to natural enemies (30–60 %). Biscaya and NeemAzal T/S is correlated with an equivalent mortality percents (50–65 %) to wheat insect pests and resulted in a smaller percentage reduction of natural enemies (10–40 %) compared to Karate. Thrips and cereal bugs were more affected than leafhoppers. Lacewings and dance flies were more susceptible; while spider, syrphids and parasitoid wasps were more tolerant. Compatibility between natural insecticides and natural enemies is highly required to keep the environment clean.     

Agro-?koeffizienz im Maisanbau durch Selektion des Sortenmaterials und Ermittlung der Reifestadien von Siliermais (Silo- und Energiemais) – aus der Sicht von ?konomie und ?kologie

Data from silage maize variety trials of the years 1999?C2010 in the Central German dry region were subjected to a secondary analysis using methods of mathematical statistics: With the phenological ripeness indicators (grain dry matter content/TM of the residual plant) the differences in the ripeness dynamics of grain to residual plant and their effects on the economy and ecology compared to the current ripeness system with use-specific ripeness numbers are documented. This dependence on all directions of use in the maize of the environments and varietal types taking into account of the different plasticity of maize varieties is been quantified. The achievement of physiological ripening of the grain is the interface of all usage directions and at the same time basis for the comparable, agro-eco-efficient level of maturity (63% TM) in conjunction with the silage ripeness index (SRI of 2.8) by eco-silage maize crops. The specific characteristics of the usage directions are low and with regard to efficiency, environmental and consumer protection discussed. With the phenological stage indicator (SRI) can both replaced the DM content of the whole plant as a parameter to the harvest date of silage and energy maize as the usage-specific ripeness numbers to the variety choice for silage and grain maize. A classification of the varieties according to ripeness groups would fully correspond to the environmental maize production. In the preparation of production (breeding, approval, testing and type of election), the SRI serves as selection and during inventory management through differential ripening control in compliance with the environmental and field production conditions as ripeness index. The wide ripeness ratio between grain and residual plant is the phenotypic expression of maize varieties as indicator for the agro-eco-efficiency and multifunctional guarantee better plant health, the resource efficiency, as well as basic product safety and sustainability of the process of maize silage. A precise fixing of harvest time point (HTP) is possible only with the SRI. The correct HTP is in principle maximum possible SRI. This HTP differently from the silage optimum can be according to the environments and the type of election. Ideally a maximum high SRI of 2.9 and over to a high basic intake of ground feed when reaching for exclusive maize silage feeding ruminant more friendly, better structural efficiency and grain hardness for the bypass of starch in the small intestine. The variety and the harvest strategy are to focus their reasons of economy and ecology on a high proportion of stocks ripeness in the field of silage optimum (SRI >?2.6) reach. Standard for maximum efficiency of production process maize and its environmental and consumer protection in the field of view of social line is the reaching of the agro eco-efficient ripeness point (SRI of 2.8 at physiological ripeness of grain by 63%).     

Neophyten in Gebirgen �C Wissensstand und Handlungsbedarf

Mountains are currently less affected by plant invasions than lowland ecosystems. Since 2005 the Mountain Invasion Research Network (MIREN, www.miren.ethz.ch) investigates the risk of plant invasions into mountains and develops preventive management strategies. A database of non-native and invasive plant species in mountains worldwide includes currently some 1500 species. Particularly problematic are woody species and ornamental plants that are often pre-adapted to a mountain climate. The risk of plant invasions in mountains is expected to increase in the near future. Climate change will enable the upward movement of lowland invaders into mountain ecosystems. Increased anthropogenic land use and disturbances and a shift of land use from grazing systems to tourism, which will lead to the introduction of new non-native plants, may further increase invasion risks. Mountains, and in particular the European Alps, are among the very few ecoregions in the world not yet badly affected by plant invasions. Managers have the unique opportunity to respond in time to an emerging threat. Preventive measures are the most effective and cost-efficient management option. Regulation of the transport of potentially invasive plant species should be a management priority. With climate change the upward movement of native lowland plants may also become a conservation concern. A broad discussion of the valuation and management of the change of mountain floras is needed. Besides plants other groups of organisms such as animal and plant pests may increasingly become a problem in mountains.     

Extremwetterlagen und Schaderreger – extreme Wissenslücken

Here we reviewed the possible impacts of weather extremes on pests (weeds, insect pests and plant pathogens) of wine, hope, apple and asparagus by analyzing scientific literature published since 1945, concerning the knowledge about the influences of extreme weather on incidence of these pests. A weather extreme event is generally defined as the occurrence of a value of a weather variable above or below a threshold value near the upper or lower tails of the range of observed values of the variable (IPCC). Although there are still many open scientific questions, climate change will likely lead to increase the frequency, intensity, spatial extent, duration and timing of weather and climate extremes and can result in unprecedented extremes. After considering all the results of derivative analysis, we concluded that the knowledge gap is enormously. Only 13 papers were found. These few papers concerning the influence of storm, hail, flooding, dryness or heavy down pours on the pests of apple (10 papers), asparagus (2 papers) or wine (1 paper). Thus projections of future impacts of extreme weather on plant pests and yields cannot be made with a high level of confidence. More research to get more primary results and data is needed urgently.     

Pflanzliche Immunit?t und ihre Anwendung im Pflanzenschutz

Intensive research on plant immunity revealed detailed knowledge on how plants recognize and defend plant pathogens. This knowledge is ready to use for genetic plant protection of crop plants, which does not rely on xenobiotic principals. Here, we report on important success in research on plant immunity and on recent and future possibilities of biotechnological plant protection that builds on intrinsic plant immunity.     

Vorratssch?digende Lepidoptera und Coleoptera in Berlin w?hrend der Jahre 1991–1997—überblick und Tendenzen

During 1991 to 1997 4078 samples sent in by public and private institutions were tested for their attack by arthropods. 5994 determinations were done. Seven the store damaging species of Lepidoptera were observed.Plodia interpunctella was the prime pest (305 determinations, mainly in cornflakes, muesli, sunflower seeds, nuts, feed, milk porredge and chocolate products). The percentage ofP. interpunctella increased from 4,3% (1991) to 5.6%–8.4% (for 1993). Larvae and adults and pure larvae samples ofP. interpunctella were mainly noticed from September to November. Pure adults samples could be counted for the most part from March to September. 27 the store damaging Coleoptera-species were determined.Stegobium paniceum was the prime pest (164 samples). 4% of the samples involvedS. paniceum. Further mainly observed beetle-species were:Lasioderma serricorne (36 samples),Tenebrio molitor (in 75 samples) andTrogoderma angustum (134 samples).

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Aktualisierte Fassung des auf der Jahrestagung des Arbeitskreises Medizinische Arachno-Entomologie der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie (K?ln/ Monheim, 1 und 2. 10. 1997) gehaltenen Vortrages.     

Pflanzenkrankheiten und Schädlinge im ökologischen Ackerbau

Zusammenfassung Auf der ökologisch bewirtschafteten Versuchsfläche des Versuchbetriebes Sickte der Biologischen Bundesanstalt wurden in der Vegetationsperiode 2002/2003 Feldversuche zur Untersuchung des Auftretens von Krankheiten und Schädlingen im ökologischen Ackerbau durchgeführt. Durch Auswertung der Ackerschlagkarteien der ökologisch bewirtschafteten Fläche und einer angrenzenden konventionell bewirtschafteten Fläche war ein ökonomischer Vergleich beider Anbausysteme unter gleichen Boden- und Klimabedingungen möglich.Insgesamt war auf Grund der trockenen Witterung das Krankheitsauftreten gering. Im Winterweizen war nach Vorfrucht Kleegras im Vergleich zur Vorfrucht Raps ein höherer Befall mit Mehltau (Erysiphe graminis) und in geringerem Umfang auch höherer Braunrostbefall (Puccinia recondita) festzustellen. Septoria-Blattdürre (Septoria tritici) wies von den genannten Krankheiten die höchste Befallshäufigkeit auf und zeigte keine Abhängigkeit von der Vorfrucht. Die Erträge variierten von 35,3 dt/ha (Sorte Bussard nach Raps) bis 70,1 dt/ha (Sorte Magnus nach Kleegras). Der Mischanbau von Weizensorten zeigte einen schwächeren Befall mit Braunrost (P. recondita), aber keinen geringeren Septoria-Befall als der Anbau der Einzelsorten.In der Sommergerste traten nur Netzflecken (Drechslera teres) mit Befallshäufigkeiten zwischen 25 und 100% in Abhängigkeit von der Sorte auf. Die Erhöhung der Aussaatstärke von 150 auf 500 Körner/m² führte zu einer leicht erhöhten Bestandsdichte und einer Ertragszunahme von 53,1 auf 68,9 dt/ha, nicht aber zu einem verstärkten Befall mit D. teres.An 5 verschiedenen Erbsensorten waren signifikante Unterschiede im Ertrag, in der Lagerneigung und hinsichtlich der Fraßschäden durch den Erbsenwickler (Cydia nigricana) feststellbar.Eine erste ökonomische Auswertung des ökologischen Ackerbaus im Vergleich zum konventionellen Anbau zeigte Vorteile für den ökologischen Anbau. Gründe hierfür sind der durch die Trockenheit hervorgerufene geringe Ertragsabstand zwischen beiden Systemen sowie die hohen Erlöse aus dem ökologischen Kartoffelanbau.     

Fusarium oxysporum- und F. proliferatum-Isolate aus Spargel und deren Pathogenit?ts��berpr��fung in einer modifizierten in vitro-Schnelltestmethode

Fusarium oxysporum and Fusarium proliferatum are important causal agents of crown and root rot of asparagus. In order to detect differences in pathogenicity and aggressiveness, two F. proliferatum and five F. oxysporum single spore isolates from asparagus spears from plantings in Austria and Germany, 55 pure cultures of F. oxysporum from asparagus roots from a planting in Hesse, Germany, and a single F. oxysporum isolate from an asparagus shoot collected in Austria were evaluated in a 28-day quick test on Hoagland??s agar in glass culture tubes. Plantlets were inoculated with spore suspensions from each respective isolate after 14 days of growth under sterile, controlled conditions in a growth chamber. A severity scale was used to assess symptoms on roots two weeks after inoculation. The effects of the single-spore isolates on root and shoot fresh weights of the plantlets were also determined. The pathogenicity of the majority of the F. proliferatum and F. oxysporum isolates included in this study was confirmed. Inoculation with pure and single-spore cultures resulted in elevated disease severity in comparison to non-inoculated controls. In particular, the two F. proliferatum isolates were found to be more aggressive than the F. oxysporum isolates. Moreover, all single spore isolates caused a reduction in fresh weight of roots and shoots in comparison to the controls. With respect to differences among asparagus cultivars, ??Ramos??, was found to be more susceptible than ??Ravel??. Overall, the quick test method was found to be capable of evaluating the pathogenicity and aggressiveness of the tested F. oxysporum and F. proliferatum isolates towards asparagus within 28 days.     

Extremwetterlagen und Auswirkungen auf Schaderreger – extreme Wissenslücken

Climate Change is likely to increase the frequency, intensity, spatial extent, duration and timing of weather and climate extremes and can result in unprecedented extremes. Managed systems like agriculture are not immune to them. Studying the rapidly growing body of climate change literature it has been noted that there are only a few papers concerning the influences of extreme weather on agriculture. Projections of future impacts of extreme weather cannot always be made with a high level of confidence. Pests (weeds, insect pests and plant pathogens) represent a major constraint to crop production. The present paper analyses scientific literature published since 1945 concerning the knowledge about the influences of extreme weather on incidence of pests in wheat, barley, maize, beet, potato, rape, forage crops and grassland. Only 63 papers were found. Insect pests and plant pathogenic fungi of maize and wheat are most investigated. The most papers describe the influences of drought, dryness heat and heavy down pours. There are enormously knowledge gaps. On the basis of this it is not possible to assess the influences of weather extremes in a changing climate on pests and yield loss current. More research in this field is needed urgently.     

Entwicklung, Samenbildung und Biomasseproduktion ausgewählter Problemunkrautarten in Rapshalbzwerghybriden

Recently semi-dwarf oilseed rape varieties appeared in practical cropping. So far, only few studies about their properties in combination with weeds are available. Recently however an increasing number of weeds that are difficult to control are observed in oilseed rape. For the experiment Anchusa arvensis (L.) M.??Bieb., Sisymbrium officinale (L.) Scop. and a mixture of three different Geranium species were selected to study their development, seed and biomass production. Consequences for cropping on semi-dwarf oilseed rape cultivars were derived from the results. Three rape cultivars different in plant height were chosen for the experiments: the normal growing variety “Viking”, the semi-dwarf variety “PR45D01” and a full dwarf rape biotype for breeding purposes. In contrast oilseed rape with normal height, infestation of light-indigently and high growing weeds is more probable in semi-dwarf oilseed rape varieties. These weeds show increased biomass production and higher seed production per plant.     

Behandlung von Reis mit Neem und Diatomeenerde zur Bek?mpfung der vorratssch?dlichen Coleopteren Sitophilus oryzae und Tribolium castaneum

The commercial available diatomaceous earth Fossil Shield® and the neem product Neem Azal-T/S® are tested as single treatments and in combination as controls for the stored product pests Sitophilus oryzae (L.) and Tribolium castaneum (Herbst). The diatomaceous earth, applied in concentrations of 0.5 g, 1 g and 2 g kg^-1 rice, reduced numbers of surviving beetles significantly (over a period of 3 weeks). A single treatment with the neem product, in concentrations of 0.01 g, 0.1 g, 0.2 g and 1 g azadirachtin kg^-1 rice, increased the mortality rate for both species significantly. The combination of neem and diatomaceous earth (1 g diatomaceous earth with 0.2 g or 1 g azadirachtin kg^-1 rice) was more effective than the single treatment in reducing numbers of surviving beetles.     

Behandlung von Reis mit Neem und Diatomeenerde zur Bek?mpfung der vorratssch?dlichen Coleopteren Sitophilus oryzae und Tribolium castaneum

The commercial available diatomaceous earth Fossil Shield® and the neem product Neem Azal-T/S® are tested as single treatments and in combination as controls for the stored product pests Sitophilus oryzae (L.) and Tribolium castaneum (Herbst). The diatomaceous earth, applied in concentrations of 0.5 g, 1 g and 2 g kg^-1 rice, reduced numbers of surviving beetles significantly (over a period of 3 weeks). A single treatment with the neem product, in concentrations of 0.01 g, 0.1 g, 0.2 g and 1 g azadirachtin kg^-1 rice, increased the mortality rate for both species significantly. The combination of neem and diatomaceous earth (1 g diatomaceous earth with 0.2 g or 1 g azadirachtin kg^-1 rice) was more effective than the single treatment in reducing numbers of surviving beetles.     

Standorteigenschaften und Anbaumanagement erklären regionale Unterschiede im Kohlherniebefall in Deutschland

In the years 2013 and 2014 the presence and the infestation level of Plasmodiophora brassicae in six federal states of Germany were assessed using a bioassay method. Soils were sampled from 237 oilseed rape fields and the farmers provided information about the soil type, the soil pH values and the last year of oilseed rape cultivation. Clubroot was detected in 66 % of the fields investigated with a mean disease severity (BI) of 0.34. Between and within the federal states differences in presence and infestation level of P. brassicae were detected. In Schleswig-Holstein significantly more fields were infected by P. brassicae (90 %) and BI was relatively high (0.49) compared to Lower Saxony, Mecklenburg-Western Pomerania and North Rhine-Westphalia with 50 % infected fields and a mean BI of 0.27. Highly infested fields (BI > 0.8) were prevalent on 15 and 25 % of fields investigated in every federal state. Within the federal states the soil climate regions (BKR) differed significantly from each other. In BKR with light and sandy soils P. brassicae was less widespread compared to neighboring BKR with loamy soils. In addition, BKR with high infestation levels on fields investigated revealed a high presence of clubroot infested fields within this BKR. The infestation level in our study was significantly influenced by soil type, content of sand and soil pH value: soil types with a sand content of 30–35 % and a pH values lower than 5.6 showed high clubroot severity and disease incidences.     

Auswirkungen des Herbizids Basta® auf die Weinrebe und den Falschen Mehltau

A field experiment was conducted in order to analyse the effects of the herbicide Basta^® with glufosinate-ammonium as the active ingredient (that inhibits specifically the enzyme glutamine-synthetase) on the grapevine plant and the infestation with Plasmopara viticola, the downy mildew pathogen. The herbicide was applied at sublethal concentrations and the toxic effects on leaves and berries based on different quality parameters were estimated. Low concentrations of glufosinate-ammonium (<?0,625?mM) did not affect the chlorophyll and amino acid concentrations in leaves. This was also the case for the content of salicylic acid and phenolic compounds. Furthermore, must parameters such as sugars (glucose and fructose), acids (tartaric acid, malic acid, total acids and volatile acids), and alcohol (ethanol and glycerine) also remained unchanged compared to the fungicide-treated or untreated control, whereas the concentrations of nitrogenous components metabolically available to yeasts increased with increasing concentrations of glufosinate-ammonium. The amount of berries harvested at the end of the experiment depended on the glufosinate-ammonium concentration applied. The harvest was highest when glufosinate-ammonium was applied as a 0.1?mM solution and differed not significantly from the fungicide-treated control, but decreased with increasing herbicide doses. However, the infestation of leaves with P. viticola was significantly reduced by the application of the herbicide, even though not each infection was eradicated due to the non-systemic mode of action of the herbicide. The particular influence of the herbicide onto this host-parasite interaction still remains unclear. Since applications of glufosinate-ammonium at low concentrations seem not to affect grapevine plants negatively, but were able to reduce the infestation with downy mildew, the specific mode of action may reveal new alternatives for the control of fungal pathogens.     

Biotechnische Regulierung der Kohlmottenschildlaus in Kohlgem��se �C Sachstand und Perspektiven

The cabbage whitefly,Aleyrodes proletella, has developed to a key pest in brassica vegetable crops throughout Germany. In a 3-year project we investigated a biotechnical approach employing netting (0.8?×?0.8 mm meshsize) in combination with the native parasitoidEncarsia tricolor in an inoculative-inundative approach in organic Brussels sprouts under field conditions. In small scale plot experiments continuous netting from transplanting in May till October alone reduced whitefly larval densities by 77 % at peak infestation in all years. Remaining whitefly infestation under net was associated with the necessity of temporary net removal for the purpose of mechanical weeding, which caused primary whitefly infestation. Release of mass rearedE. tricolour under net at the first signs of larval infestation significantly increasedA. proletella-parasitation and reduced infestation compared to netted controls without release. Furthermore, at highest dosage in 2009,E. tricolor had a significant enhancing effect on raw yield and the quality level of marketable yield. Additional on-farm experiments without netting in 2008 and 2009 confirmed the control potential ofE. tricolor. Although the most important project mile stones have been achieved, namely (a)E. tricolour-establishment under net and in the open field, (b) enhanced parasitation corresponding with pest density decline and (c) a positive impact on yield and quality parameters, further research will be necessary. The focus should be on the initial infestation period, optimizing the timing, frequency and required dosage.     

Alt?gyptische Fliegen- und K?ferrelikte in einem Priestersarg der achtzehnten Dynastie

Ancient Egyptian insect relics were accidentally enclosed in embalming resin which leaked from a priest's mummy and solidified on the floor of a wooden coffin from the end of the XVIII^th Dynasty (presumably 1323–1295 BC). The preserved insect relics were blowflies (Calliphoridae) recognized as Chrysomya marginalis or Chrysomya megacephala whose larvae had developed by feeding on the deceased's body prior to mummification as well as furniture beetles (Anobiidae) being either Oligomerus ptilinoides or Priobium carpini whose larvae had ingested the coniferous wood of the coffin. It is most likely that the human corpse and coffin were first attacked by the blowflies and furniture beetles prior to embalming, while infestation of the insect remains and textiles by Anthrenus sp. (Dermestidae) occurred in our time.