Untersuchungen zur Ätiologie von Phytophthora-Primärbefall an Kartoffeln

Phytophthora-Primärbefall an Kartoffeln hat in den letzten Jahren zunehmend an Bedeutung gewonnen. Über die Ursachen und die auslösenden Faktoren von Primärbefall herrscht noch viel Unklarheit

Spectrophotometry of planets, asteroids and satellites from the international ultraviolet explorer satellite

A total of 14 8 hour I.U.E. observing sessions resulted in 39 spectra of 11 asteroids and 9 solar type stars as well as 57 spectra at various locations on the disk of Jupiter. The Jupiter observations include a total of 5 center to limb series of spectra at various latitudes and a North South series along the central meridian. In the range from 2000-3000 A, the planet shows a striking decrease in brightness at latitudes greater than about 30 degrees, and exhibits limb brightening at low latitudes and limb darkening at high latitudes. Preliminary results indicate that about 6 km-amagats of clean hydrogen are required above a haze of absorbing aerosols to reproduce the limb brightening observed at 2500 A in the equatorial regions. At higher latitudes, the aerosols extend to even higher levels of the atmosphere. Comparison of the Jovian data with detailed model calculations and the analyses of the asteroid spectra are still in progress with other support

Reduzierung des Phytophthora-Primärbefalls durch eine Kupferbeizung unter den besonderen Bedingungen des Ökologischen Kartoffelanbaus

Im ökologischen Kartoffelanbau stellt der Primärbefall ein großes Problem dar, weil er mit Kupferspritzungen nur schwer zu kontrollieren ist und schnell zum vorzeitigen Ausbruch von Sekundärbefall führen kann. Nach ergiebigen Niederschlägen und hoher Bodenfeuchte kann der Erreger Phytophthora infestans entweder von der latent infizierten Pflanzknolle im Stängel nach oben wachsen oder auf der Oberfläche der Pflanzknolle sporulieren. Unter für den Erreger optimalen Witterungsbedingungen können beide Infektionswege einen Primärbefall am Stängel auslösen

Strategien zur Minimierung des Einsatzes kupferhaltiger Fungizide bei der Krautfäulebekämpfung im Ökologischen Kartoffelanbau – ein vom Bundesprogramm Ökologischer Landbau gefördertes Forschungsprojekt

Ziel des Projektes ist es, auf Basis der witterungsbedingten Epidemiebewertung, die Kupferaufwandmengen auf das absolut notwendige Maß zu begrenzen. Dazu werden verschiedene Strategien verfolgt. Zum einen soll durch eine Pflanzgutbeizung mit Kupferpräparaten das Auftreten von Primärbefall reduziert werden, um den Epidemiebeginn und somit auch den Spritzstart nach hinten verlagern zu können. Zum andern werden zur Kontrolle des Sekundärbefalls Applikationsstrategien erarbeitet, bei denen die Kupferaufwandmengen und die Spritzabstände variabel an den Infektionsdruck angepasst werden, um mit möglichst niedrigeren Mengen auszukommen

Population Update, Report Number 3

There is more to population study than merely knowing how many people live in a geographical location. Two of the most important other aspects of demography are the age and sex composition of a population. Should planners be thinking about adding space to a grammar school or to a retirement center? By studying age and sex compositions, they will make more accurate decisions. The distribution of a population by age and sex is often shown in a pyramid. The bars in the pyramid (see inside) represent age groups spaced at 5-year intervals. The pyramid is also divided in the middle, with the males at the left and the females at the right. State pyramids for 1960, 1970, and 1975 point up interesting trends. One of the most significant is a lowered birth rate. Thus, the base of the pyramid reflecting the children is shrinking. Statewide services required for the very young may not need expansion. On the other hand, those born around 1960, when the birth rate was higher, are now young adults and form an exaggerated proportion of the state\u27s population. Jobs and higher education are their major concerns. Should we build more colleges and technical schools to accommodate these young people? Look at the age structure at the bottom of the pyramid. In 10 years who is going to fill those schools? Perhaps educators should think in terms of temporary measures to alleviate present difficulties- extension courses, night classes, and the like. Population ratios and indexes like those under the detailed state totals can also be useful. Although pyramids are not portrayed, indexes and ratios as described below are provided for each county

Population Update, Report Number 2

It might be suggested that economics are important in a reverse sort of way. No longer can urban centers offer economic opportunity to potential rural outmigrants, and these people are simply staying at home. Between 1960 and 1970, 53 of South Dakota\u27s 67 counties were losing population. At an extreme, Stanley County dropped 40%; Fall River 30%; and Clark, Harding and Jackson lost nearly one fourth of their inhabitants. In the next 5 years (1970-1975) these same counties had not only stopped losing, but were actually gaining population. While only 14 counties gained population between 1960 and 1970, 38 showed gains between 1970 and 1975. Of the 29 counties still losing population, 19 lost a smaller percentage from 1970 to 1975 than in the decade from 1960 to 1970. Only two counties that gained population between 1960 and 1970 (Yankton and Lawrence) lost population between 1970 and 1975

Harold Jeffreys's Theory of Probability Revisited

Published exactly seventy years ago, Jeffreys's Theory of Probability (1939) has had a unique impact on the Bayesian community and is now considered to be one of the main classics in Bayesian Statistics as well as the initiator of the objective Bayes school. In particular, its advances on the derivation of noninformative priors as well as on the scaling of Bayes factors have had a lasting impact on the field. However, the book reflects the characteristics of the time, especially in terms of mathematical rigor. In this paper we point out the fundamental aspects of this reference work, especially the thorough coverage of testing problems and the construction of both estimation and testing noninformative priors based on functional divergences. Our major aim here is to help modern readers in navigating in this difficult text and in concentrating on passages that are still relevant today.Comment: This paper commented in: [arXiv:1001.2967], [arXiv:1001.2968], [arXiv:1001.2970], [arXiv:1001.2975], [arXiv:1001.2985], [arXiv:1001.3073]. Rejoinder in [arXiv:0909.1008]. Published in at http://dx.doi.org/10.1214/09-STS284 the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Strategien zur Reduzierung der Kupferaufwandmengen im ökologischen Kartoffelanbau – Projekt “ÖKO-SIMPHYT“

Potato late blight (Phytophthora infestans) is still an unsolved problem in organic farming. Up to now the disease can only be controlled by copper fungicides. Our project is aiming to reduce the application of copper-containing fungicides by introduc-tion of the new blight forecasting system “ÖKO-SIMPHYT” based on meteorological parameters. Primary stem infections should be reduced by seed treatment with copper fungicides thus to postpone the beginning of the blight epidemic as well as the start of spraying. To control secondary infections on the foliage, fungicide strategies should be elaborated to achieve best efficacy with reduced amounts of copper. Therefore copper amounts and spraying intervals should be adjusted to the infection pressure. Based on the biological and epidemiological conditions for primary and secondary infections the new developed potato blight forecast system ÖKO-SIMPHYT should be optimized

Möglichkeiten zur Optimierung der Kupferwirkung gegen Krautfäule im Ökologischen Kartoffelanbau

Die Regulierung der Kraut- und Knollenfäule, verursacht durch Phytophthora infestans, stellt im ökologischen Landbau nach wie vor ein nur schwer zu lösendes Problem dar. Bislang ist eine befriedigende Befallsreduktion nur durch den Einsatz kupferhaltiger Pflanzenschutzmittel möglich, deren Einsatz durch die Anbauverbände, sofern überhaupt gestattet, auf 3kg pro Jahr begrenzt ist. Im Rahmen des Projekts „ÖKO-SIMPHYT“ wurden daher verschiedene Kupferapplikationsverfahren zur Bekämpfung der Phytophthora infestans-Sekundärinfektionen untersucht, um die zur Verfügung stehenden Kupfermengen optimal einzusetzen