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Aufsatz
Low-altitude aerial photography for optimum N fertilization of winter wheat on the North China Plain
(2004)
Previous research has shown that site-specific nitrogen (N) fertilizer recommendations based on an assessment of a soil’s N supply (mineral N testing) and the crop’s N status (sap nitrate analysis) can help to decrease excessive N inputs for winter wheat on the North China Plain. However, the costs to derive such recommendations based on multiple sampling of a single field hamper the use of this approach at the on-farm level. In this study low-altitude aerial true-color photographs were used to examine the relationship ...
Aufsatz
Bacterial ecology of ancient Saharan salt-enrichment ponds at Teguidda-n-Tessoumt
(2005)
Little is known about the bacterial ecology of evaporative salt-mining sites (salterns) of which Teguidda-n-Tessoumt at the fringe of the West-African Saharan desert in Niger is a spectacular example with its many-centuries-old and very colorful evaporation ponds. During the different enrichment steps of the salt produced as a widely traded feed supplement for cattle, animal manure is added to the crude brine, which is then desiccated and repeatedly crystallized. This study describes the dominant Bacteria and Archaea ...
Technischer Report
Evaluating the state of the art of parallel programming systems
(Universität Kassel, FB 16, Elektrotechnik/Informatik, 2005-12-20)
This paper describes our plans to evaluate the present state of affairs concerning parallel programming and its systems. Three subprojects are proposed: a survey among programmers and scientists, a comparison of parallel programming systems using a standard set of test programs, and a wiki resource for the parallel programming community - the Parawiki. We would like to invite you to participate and turn these subprojects into true community efforts.
Aufsatz
Plant genetic diversity, irrigation and nutrient cycling in traditional mountain oases of northern Oman
(Li, C. J. (u.a.) (Hrsg.), 2005)
Little is known about plant biodiversity, irrigation management and nutrient fluxes as criteria to assess the sustainability of traditional irrigation agriculture in eastern Arabia. Therefore interdisciplinary studies were conducted over 4 yrs on flood-irrigated fields dominated by wheat (Triticum spp.), alfalfa (Medicago sativa L.) and date palm (Phoenix dactylifera L.) in two mountain oases of northern Oman. In both oases wheat landraces consisted of varietal mixtures comprising T. aestivum and T. durum of which ...
Aufsatz
A note about Triticum in Oman
(2003)
Little is known about the diversity of wheat (Triticum spp.) in Oman. Results of a survey conducted in two remote mountain oases of northern Oman indicate that there exists considerable morphological variation within and among the five traditional landraces of wheat cultivated. Within two of the landraces grown on irrigated terraces, 2 sized between 2 and 100 m , two new botanical wheat varieties (Triticum aestivum var. baladseetense and var. maqtaense) were identified of which the agronomic properties, in particular ...
Dissertation
Pathogens occuring in the winter pea-maize-winter wheat rotation, their host specificity and the potential of compost in suppressing foot and root disease of peas
(2015-09-17)
The overall aim of the work presented was to evaluate soil health management with a specific focus on soil borne diseases of peas. For that purpose field experiments were carried out from 2009 until 2013 to assess crop performance and pathogen occurrence in the rotation winter pea-maize-winter wheat and if the application of composts can improve system performance. The winter peas were left untreated or inoculated with Phoma medicaginis, in the presence or absence of yard waste compost at rate of 5 t dry matter ha-1. ...
Dissertation
Etiology of Maize Root rot in Oman: Causal agents and effects of a compost based organic growing system
(2018-08-16)
Summary:
In Oman, the main cereal crop Maize is facing serious problems due to high salinity, alkaline soils with low organic matter, high temperatures, and root rot diseases. Production peaked at 40,000 t in 2011 but dropped to less than 15,000 t in 2014.
A survey on maize root rot in eight maize growing governorates in Oman yielded nine fungal and oomycetes species of which Pythium arrhenomanes and Fusarium fujikuroi were first reports on maize in Oman. Both are able to attack multiple hosts. Under controlled ...
Dissertation
Studies on the diversity of the main necrotrophic pathogens on wheat and barley Pyrenophora tritici-repentis and Cochliobolus sativus
(2017-10-30)
Leaf blights such as tan spot of wheat (Pyrenophora tritici-repentis) and spot blotch of barley (Cochliobolus sativus) are among the main constraints in achieving high and stable yields and are the main concerns among the several intrinsic drawbacks of narrow cropping sequencesas both are residue borne. The development of useful and durable resistance against prevalent races requires detailed information on the virulence diversity of the pathogen and the type of resistances available in the host. Thus, the focus of ...
Dissertation
Flächenhafte und funktionale Analyse kleinräumiger standortbedingter Variationen der Grünlandvegetation und -produktivität
(2009-07-27)
Zur Abbildung heterogener Standorteigenschaften und Ertragspotenziale werden zunehmend flächenhafte Daten nachgefragt. Insbesondere für Grünland, das häufig durch ausgeprägte Standortheterogenität gekennzeichnet ist, ergeben sich hohe Anforderungen an die Wiedergabequalität, denn die realen Verhältnisse sollen in praktikabler Weise möglichst exakt abgebildet werden. Außerdem können flächenhafte Daten genutzt werden, um Zusammenhänge zwischen teilflächenspezifischen Standorteigenschaften und Grünlandaspekten detaillierter ...
Dissertation
The status and barriers to the implementation and continuation of the school gardening projects in Germany, Nigeria and the United States of America
(2010-10-25)
In drawing a conclusion for this study, care must be taken in generalizing findings since the population of students and teachers investigated were limited to certain levels in the different schools and countries. This study recognized some complexity of the factors underlying the status of school gardening instruction and activities in Germany, Nigeria and the U.S. as inadequate time for decision-making in the process of gardening, motivation of teachers and students. This was seen as the major impediments that ...