scholarly journals Infection biology as the basis of integrated control of apple canker (Neonectria ditissima) in Northern Europe

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Roland W. S. Weber ◽  
Jorunn Børve
Keyword(s):  
Vegetative Growth ◽  
Integrated Control ◽  
Field Trials ◽  
Northern Europe ◽  
Leaf Fall ◽  
Northern Germany ◽  
Long Distance ◽  
Main Trunk ◽  
Standard Tree ◽  
Apple Canker

Abstract Background European canker, caused by Neonectria ditissima, is a disease of worldwide importance in apple production, yet knowledge about it is limited, highly regional and sometimes contradictory. This is an obstacle to successful disease management. Key aspects for Northern Europe are reviewed, based on research results from Northern Germany and Norway and on international literature data. Main topics Trunk cankers developing on young trees within the first 1–3 seasons of explanting can often be traced back to latent infections initiated in the nurseries. The most important nursery infection is a lateral canker on the main trunk of ‘knip’ trees, which are the standard tree type in Northern Europe. In strongly affected batches, up to 25% of trees have to be uprooted after the first growing season due to such trunk cankers. The establishment and maintenance of healthy orchards requires clean nursery material, especially in the case of susceptible cultivars. In Northern Germany, infections within commercial orchards most often proceed through wounds caused by fruit picking or leaf fall in autumn, as shown by the appearance of cankers in the following spring and by the high efficacy of fungicide treatments at leaf fall. Ascospores, commonly thought to be relevant for long-distance spread of infections, are not released until the end of leaf fall even in wet autumn seasons in Northern Germany. Therefore, their role in the disease remains unclear. Strong nitrogen-induced vegetative growth favours apple canker. In field trials conducted under conditions of current commercial practices, autumnal sprays with copper hydroxide or copper oxide were consistently more efficacious than copper oxychloride or captan in preventing new infections. Conclusions Restricted fertilisation and other measures to curb excessive vegetative growth during the first few years of an orchard, repeated canker pruning and well-timed treatments with effective fungicides in autumn are essential for IPM of apple canker. Nonetheless, canker remains capable of severely impairing the commercial success of susceptible cultivars in regions with wet climates even if all available measures are taken. This opens up long-term perspectives for the breeding of more resistant cultivars.

scholarly journals Integrated Control of Rhizoctonia Crown and Root Rot of Sugar Beet with Fungicides and Antagonistic Bacteria

Plant Disease ◽  
2001 ◽  
Vol 85 (7) ◽  
pp. 718-722 ◽  
Author(s):  
Sebastian Kiewnick ◽  
Barry J. Jacobsen ◽  
Andrea Braun-Kiewnick ◽  
Joyce L. A. Eckhoff ◽  
Jerry W. Bergman
Keyword(s):  
Sugar Beet ◽  
Root Rot ◽  
Integrated Control ◽  
The United States ◽  
Field Trials ◽  
Sugar Yield ◽  
Economic Losses ◽  
Yield Increase ◽  
Leaf Stage ◽  
Crown And Root Rot

Rhizoctonia crown and root rot, caused by the fungus Rhizoctonia solani AG 2-2, is one of the most damaging sugar beet diseases worldwide and causes significant economic losses in more than 25% of the sugar beet production area in the United States. We report on field trials in the years 1996 to 1999 testing both experimental fungicides and antagonistic Bacillus sp. for their potential to reduce disease severity and increase sugar yield in trials inoculated with R. solani AG 2-2. Fungicides were applied as in-furrow sprays at planting or as band sprays directed at the crown at the four-leaf stage, or four- plus eight-leaf stage, while bacteria were applied at the four-leaf stage only. The fungicides azoxystrobin and tebuconazole reduced crown and root rot disease by 50 to 90% over 3 years when used at rates of 76 to 304 g a.i./ha and 250 g a.i./ha, respectively. The disease index at harvest was reduced and the root and sugar yield increased with azoxystrobin compared with tebuconazole. The combination of azoxystrobin applied at 76 g a.i./ha and the Bacillus isolate MSU-127 resulted in best disease reduction and greatest root and sucrose yield increase.

North European Rock Art

2017 ◽  
Author(s):  
Joakim Goldhahn
Keyword(s):  
Bronze Age ◽  
Iron Age ◽  
Rock Art ◽  
Northern Europe ◽  
Long Distance ◽  
Migration Period ◽  
Farming Communities ◽  
And Migration ◽  
The Bronze Age

This chapter offers a long-term perspective on rock art in northern Europe. It first provides an overview of research on the rock art traditions of northern Europe before discussing the societies and cultures that created such traditions. It then considers examples of rock art made by hunter-gatherer societies in northern Europe, focusing on the first rock art boom related to Neolithization. It also examines the second rock art boom, which was associated with social and religious changes within farming communities that took place around 1600–1400 bc. The chapter concludes by analysing the breakdown of long-distance networks in the transition from the Bronze Age to the Iron Age and its consequences for the making of rock art within the southern traditions, as well as the use of rock art sites during the Pre-Roman Iron Age, Roman Iron Age, and Migration Period.

Rural Centres, Trade, and Non-Agrarian Production

2002 ◽  
Author(s):  
Helena Hamerow
Keyword(s):  
State Formation ◽  
Craft Production ◽  
Northern Europe ◽  
Viking Age ◽  
Rural Settlements ◽  
Long Distance ◽  
Farming Communities ◽  
Before And After ◽  
Trade And Exchange ◽  
High Level

In contrast to the relative scarcity of publications dealing with the buildings and layouts of rural settlements, many volumes have been devoted to the development of early medieval trade and craft production (e.g. Jankuhn et al. 1981; 1983; K. Düwel et al. 1987, vols. 1–4; Hodges and Whitehouse 1983). Archaeological research into these topics has been made more fruitful—as well as more complex—by the contributions of neighbouring disciplines such as history, geography, and numismatics. It has, however, tended to focus almost exclusively on towns, monasteries, and royal centres, yet craft production, trade, and exchange also played a significant role in farming communities before and after the emergence of such specialized centres. Indeed, the rural settlements of northwest Europe were already significantly differentiated in their economies in the Migration period, suggesting a high level of socio-economic complexity several centuries earlier than has generally been supposed. The evidence now available for trade and non-agrarian production, which derives almost wholly from archaeology, calls for a thoroughgoing reassessment of when and how centralized authorities emerged in northern Europe after the collapse of the western Empire. This is particularly true for northern Germany and southern Scandinavia, where early state formation has conventionally been dated to the late Viking period. Research into state formation has in the past focused on the origins of towns and market centres, the latter usually seen as arising from participation in long-distance trade which was controlled by kings or magnates. Yet, several centuries before there were kings or towns in northern Europe, rural settlements emerged which point to a degree of political centralization. This chapter considers the evidence for these rural centres and the role of non-agrarian production and exchange in rural settlements generally: what was the scale and context of the production, distribution, and consumption of non-agrarian goods? Who controlled these activities, and how, if at all, did the long-distance trade networks which fuelled the nascent towns of Merovingian and Viking Age Europe affect the economies of the communities which lay in their hinterlands?

Amber Sources and Trade in the Prehistory of the Iberian Peninsula

2012 ◽  
Vol 15 (2) ◽  
pp. 187-216 ◽  
Author(s):  
Mercedes Murillo-Barroso ◽  
Marcos Martinón-Torres
Keyword(s):  
Iberian Peninsula ◽  
Northern Europe ◽  
Review Of The Literature ◽  
Long Distance ◽  
Trade Networks ◽  
Ftir Characterization ◽  
Fossil Resin ◽  
Chalcolithic Period ◽  
The Fourier Transform

The use of amber is documented in the Iberian peninsula since the Palaeolithic. The procurement and trade of this fossil resin has often been considered in discussions of long-distance trade and the emergence of social complexity, but so far no comprehensive view of the Iberian evidence has been produced to allow a more overarching interpretive model. This paper presents the Fourier-transform infrared spectroscopy (FTIR) characterization of archaeological amber from three Iberian prehistoric sites: a necklace recovered from the megalithic site of Palacio III (Almadén de la Plata, Sevilla), a pommel from PP4 Montelirio (Valencina de la Concepción, Sevilla), and a necklace from the Muricecs de Cellers cave (Llimiana, Pallars Jussà, Lleida). Based on these new data and a review of the literature, we present an overview that outlines fluctuations in the use of amber since the Upper Palaeolithic and demonstrates long-distance amber exchange connecting Iberia with northern Europe and the Mediterranean region since the Chalcolithic period at least. We discuss changes in the origins and cultural use of amber and their implications for the consolidation of trade networks.

Factors Affecting the Structure of Song and the Singing Behaviour of Some Northern European Passerine Birds

Behaviour ◽  
1986 ◽  
Vol 98 (1-4) ◽  
pp. 286-304 ◽  
Author(s):  
Jorma Sorjonen
Keyword(s):  
Northern Europe ◽  
Passerine Birds ◽  
Long Distance ◽  
Factors Affecting ◽  
The North ◽  
Northern European ◽  
Northern Areas ◽  
Size Limitation ◽  
Short Time ◽  
Forest Habitats

AbstractIn this study the effects of bird size, genus, habitat, song community and geographical distribution on song structure and singing behaviour of some passcrine species in northern Europe were simultaneously studied. Most species tend to improve their long distance song propagation in their specific habitat and song community. Song propagation correlates strongest with the use of low-pitched elements but not all birds are able to use these because of size limitation. In forest habitats whistles and modulated elements were used to improve song propagation. In open habitats high-pitched elements as well as repeated and trilled syllables were often used for better propagation of acoustic information. In song communities with a great number of species, the birds reduce song interference by other singers, by singing short songs and using modulated elements and long intersong pauses. When the birds greatly profit from effective long distance song propagation, like in northern areas with only short time for pair formation, the birds can segregate in singing time by using the light nights for singing. In these communities with low numbers of species the birds have been freed from song interference and have long songs and short intersong pauses and they can increase in this way their singing rate. The effect of song community on song length, intersong pause and the use of modulated elements in the song is stronger than that of habitat. The effect of the song community increases towards the north.

Studies on the Potential of Winged Bean as a Multipurpose Legume Cover Crop in Tropical Regions

1984 ◽  
Vol 20 (4) ◽  
pp. 297-301 ◽  
Author(s):  
Anjana Banerjee ◽  
D. K. Bagchi ◽  
L. K. Si
Keyword(s):  
Vegetative Growth ◽  
Cover Crop ◽  
Dry Matter ◽  
Field Trials ◽  
Winged Bean ◽  
Tropical Regions ◽  
Growing Period ◽  
Whole Plant ◽  
Legume Cover Crop ◽  
Cultivation Methods

SUMMARYThe potential of winged bean as a multipurpose legume cover crop was shown in field trials by its abundant vegetative growth throughout the growing period of two years. Protein contents of the dry matter of the whole plant, vegetable pods, seeds and tubers were in the range 22–34, 25–30, 32–38 and 16–19%, respectively. In a comparison of two cultivation methods, significantly higher yields were obtained from staked plants than from those grown without supports; protein contents, however, remained constant.

scholarly journals The comparison of several soil cultivation methods in the Tokaj-wine region

2008 ◽  
Vol 14 (3) ◽  
Author(s):  
J. Göblyös ◽  
A. Ulcz
Keyword(s):  
Moisture Content ◽  
Vegetative Growth ◽  
Titratable Acidity ◽  
Long Distance ◽  
Soil Cultivation ◽  
Straw Mulch ◽  
Grape Quality ◽  
Cultivation Methods ◽  
Wine Region

Our results show that the different cultivation methods have higher effect on the yield than on the grape quality. In 2007 the weather was extreme dry (from May to August only 195 mm precipitation was recorded) the straw mulch proved to be the best solution regarding the yield and the grape quality. Although no significant differences were observed in the sugar- and titratable acidity content of the must, the ratio of noble rotted berries was higher on the straw mulched plots. Straw mulch could conserve the moisture content of the soil and it seems to be contributed to the conformation of suitable microclimate for Botrytis infection, but for long distance conclusions further examinations need to be investigated. The less yield and ratio of rot was observed in case of barely covered vines and the vegetative growth of the grape was less intensive in case of these vines.

Dating Late Paleolithic Harpoons from Lake Lubāns, Latvia

Radiocarbon ◽  
2014 ◽  
Vol 56 (02) ◽  
pp. 581-589 ◽  
Author(s):  
John Meadows ◽  
Berit V Eriksen ◽  
Ilga Zagorska ◽  
Alexander Dreves ◽  
Joanna Simpson
Keyword(s):  
Mass Spectrometry ◽  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Isotope Analysis ◽  
Northern Europe ◽  
Northern Germany ◽  
National History ◽  
History Museum ◽  
Late Paleolithic ◽  
Ams Dating

Over 3000 prehistoric bone and antler artifacts, collected in the late 1930s from the former lakebed of Lake Lubāns, are held by the National History Museum of Latvia. This collection is remarkable not only as one of the largest known assemblages of bone implements in northern Europe, but also in terms of diversity of forms. The most elaborately worked objects include harpoons, often with two rows of barbs and spade-shaped bases, which are believed to date to the Late Paleolithic, and to be among the oldest organic artifacts ever found in Latvia. Four broken specimens were sampled in 2011 for accelerator mass spectrometry (AMS) dating, stable isotope analysis, and taxonomic attribution by ZooMS. The results support the interpretation that these artifacts were made from large cervid bones, and date all four objects to the early Preboreal (mid-10th millennium cal BC). The Lake Lubāns harpoons therefore fall in the same period as similar harpoons from Denmark, northern Germany, and Poland, although only a handful of these have been dated directly.

Dispersal of white spruce seed in mature aspen stands

1998 ◽  
Vol 76 (2) ◽  
pp. 181-188 ◽  
Author(s):  
James D Stewart ◽  
Edward H Hogg ◽  
Patrick A Hurdle ◽  
Kenneth J Stadt ◽  
Peter Tollestrup ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Populus Tremuloides ◽  
Picea Glauca ◽  
White Spruce ◽  
Simulation Modelling ◽  
Dispersal Distance ◽  
Leaf Fall ◽  
Long Distance ◽  
Artificial Seed ◽  
The Mean

The dispersal of white spruce (Picea glauca (Moench) Voss) seed through trembling aspen (Populus tremuloides Michx.) forests was investigated by releasing artificial seed (confetti) from different heights on a meteorological tower, and, secondly, by observing the distribution of spruce regeneration along transects radiating out from small isolated patches of mature spruce seed trees. Mean dispersal distance of confetti increased with height of release. Before leaf fall of the aspen canopy, most confetti landed close to and in all directions around the tower. After leaf fall, no confetti was observed upwind from the tower and the mean dispersal distance increased, with peak densities occurring at a distance of 15 m in the downwind direction. The rate of decrease in regeneration density with distance from patches of mature, seed-bearing white spruce was much less than that observed during confetti release experiments. Furthermore, regeneration densities were significantly greater in the prevailing downwind direction (toward the east). The results indicate that stronger than average winds, primarily from the northwest, west, and southwest, play a major role in the dispersal of white spruce seed. Simulation modelling of the observed distribution of regeneration suggests that long-distance (>250 m) dispersal may be an important mechanism for the persistence of white spruce in the fire-prone boreal forest of western Canada.Key words: seed dispersal, boreal forest, mixedwood, wind dispersal, artificial seed.

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