Landwirtschaftliches Technologiezentrum Augustenberg

Climate change, with its rising temperatures and altered precipitation patterns, is expected to reduce soil moisture during critical phases of plant growth. This will lead to increased water stress and lower crop yields. As the frequency of low-yield years rises, farmers will become increasingly interested in irrigation as a means to stabilize crop production. This trend could accelerate if government subsidies for irrigation infrastructure increase in response to recurring low yields.This shift towards increased irrigation may be particularly relevant for Germany, where in most regions irrigation is limited to few specialty crops. The present study focuses on the potential impact of increased irrigation in a 400 km² area south of Stuttgart, encompassing the morphological catchment of the Ammer River and part of the Neckar Valley near Tübingen. Since irrigation is not widely practiced in this region, it provides a unique opportunity to clearly demonstrate the effects of a possible transition to irrigation agriculture.To analyze these impacts, the crop model ExpertN was used to simulate irrigation requirements for each of the region's 300 soil-weather units. The model incorporates detailed processes, such as water flow within soil layers (Richards equation) and evapotranspiration (based on the Penman-Monteith equation), to accurately describe soil moisture dynamics. Additionally, the model includes nitrogen cycling, enabling an assessment of increased irrigation to nitrate leaching.The study highlights key outcomes, including the water demand for irrigation, additional moisture losses through evaporation, and increases in deep percolation under varying irrigation intensities. Furthermore, we evaluate the effects of irrigation on regional crop production, providing valuable insights for sustainable agricultural management under a changing climate.

A winter wheat composite cross population (CCP), created in the UK in 2001, has been grown in Germany, Hungary, and the UK since 2005 (F5 generation). In 2008/09 (F8), a cycling pattern for the populations was developed between partners to test the effects of rapidly changing environments on agronomic performance and morphological characteristics. One CCP was grown by eight partners for one year and subsequently sent to the next partner, creating “cycling CCPs” with different histories. In 2013, all eight cycling CCPs and the three non-cycling CCPs (from Germany, Hungary, and the UK) were included in a two-year experiment in Germany with three line varieties as references. Differing seed weights of the F13 at sowing affected some agronomic parameters under drought conditions in 2014/15 but not under less stressful conditions in 2013/14. In both experimental years, the CCPs were comparable to the line varieties in terms of agronomic performance, with some CCPs yielding more than the varieties under the drought conditions of 2015. The results highlight the potential of CCPs to compete with line varieties, while the overall similarity of the CCPs based on their origin and cycling history for agronomic traits indicates a high buffering potential under highly variable environmental conditions.

Abstract BackgroundFertilization with organic waste compost can close the nutrient cycles between urban and rural environments. However, its effect on yield and soil fertility must be investigated.AimThis study investigated the long‐term effect of compost on soil nutrient and potentially toxic elements (PTEs) concentration, nutrient budgets, and nitrogen (N) mineralization and efficiency.MethodsAfter 21 years of annual compost application (100/400 kg N ha–1 year–1 [100BC/400BC]) alone and combined with mineral fertilization, soil was analyzed for pH, organic carbon (SOC), nutrient (total N and P, Nmin, extractable CAL‐P, CAL‐K, and Mg), and PTE (Cu, Ni, Zn) concentrations. Yields were recorded and nutrient/PTE budgets and apparent net mineralization (ANM, only 2019) were calculated.ResultsN efficiency was the highest in maize and for mineral fertilization. Compost application led to lower N efficiencies, but increased ANM, SOC, pH, and soil N, and surpluses of N, P, and all PTEs. Higher PTE concentrations were only found in 400BC for Cu. Nutrient budgets correlated with soil nutrient concentration. A surplus of 16.1 kg P ha–1 year–1 and 19.5 kg K ha–1 year–1 resulted in 1 mg kg–1 increase in CAL‐P and CAL‐K over 21 years.ConclusionCompost application supplies nutrients to crops with a minor risk of soil‐accumulation of PTEs. However, the nutrient stoichiometry provided by compost does not match crop offtakes causing imbalances. Synchronization of compost N mineralization and plant N demand does not match and limits the yield effect. In winter wheat only 65–70% of N mineralization occurred during the growth period.

Abstract A recycling of Phosphorus (P) from the human food chain is mandatory to secure the future P supply for food production. However, many available recycled P fertilizers from sewage sludge do not have an adequate P bioavailability and, thus, are not suitable for their application in soils with pH >5.5–6.0, unless being combined with efficient mobilization measures. The aim of the study was to test the P mobilization ability of red clover ( Trifolium pratense L.) from two thermally recycled P fertilizers for a subsequently grown maize. Two sewage sludge ashes (SSA) were investigated in a pot experiment at soil pH 7.5 with red clover differing in its nitrogen (N) supply (added N fertilizer or biological N 2 fixation (BNF)), followed by maize ( Zea maize L.). Shoot dry matter of maize was almost doubled when N supply of previous grown clover was covered by BNF, instead of receiving added N fertilizer. Similarly, shoot P removal of maize following clover with BNF was significantly increased. It is suggested that the P mobilization is related to the BNF, and a proton release of N 2 fixing clover roots led to the measured decrease in soil pH and thereby increased P availability of the tested fertilizers.

Identifying migratory corridors of animals is essential for their effective protection, yet the exact location of such corridors is often unknown, particularly for elusive animals such as bats. While migrating along the German coastline, Nathusius' pipistrelles (Pipistrellus nathusii) are regularly killed at wind turbines. Therefore, we explored the paths taken on their annual journey. We used isotope ratio mass spectrometry to measure stable hydrogen and strontium isotope ratios in fur keratin of 59 Nathusius' pipistrelles captured on three offshore islands. Samples were pre-treated before analysis to report exclusively stable isotope ratios of non-exchangeable hydrogen. We generated maps to predict summer origins of bats using isoscape models. Bats were classified as long-distance migrants, mostly originating from Eastern Europe. Hydrogen analysis suggested for some bats a possible Fennoscandian origin, yet additional information from strontium analysis excluded this possibility. Instead, our data suggest that most Nathusius' pipistrelles migrating along the German coastline were of continental European summer origin, but also highlight the possibility that Nathusius' pipistrelles of Baltorussian origin may travel offshore from Fennoscandia to Germany. Our findings demonstrate the benefit of using complementary isotopic tracers for analysing the migratory pathways of bats and also potentially other terrestrial vertebrate species. Furthermore, data from our study suggest an offset of fur strontium isotope ratios in relation to local bedrock.

Recent examples for the introduction of wood-breeding beetles in Europe include the asian longhorn beetles Anoplophora spp. and Aromia bungii (red-necked longhorn beetle). These and other woodboring beetle species pose a high risk of economic damage to trees and wood products. Smaller beetles like the powderpost beetles from the families Bostrichidae and Lyctidae also have the potential for causing considerable damage. These are often not identified adequately during inspections of wood packaging materials, making it impossible to assess their risk for becoming invasive. This project will aim at closing that gap. Our project PHID-Coleo (= Plant Health Identification of Coleoptera) has the objective to develop new diagnostic tools for the identification of potentially invasive and economically important beetles that can be found in wood packaging materials. The identification methods include classical identification keys based on morphological characters as well as molecular methods based on DNA analysis by PCR (barcoding). The methods for species identification will be supplemented by molecular analyses of introduced populations to clarify within species variations. Such methods will make it possible to determine the taxonomic relationship of samples from different areas and to draw conclusions about the introduction pathways, resulting in more efficient monitoring of the invasive species and preventing their spread. PHID-Coleo will build a freely accessible database of relevant species which are potentially invasive.

Im Sommer 2017 kam es in einer Apfelanlage bereits drei Monate nach der Pflanzung zu Baumausfallen. Die absterbenden Baume wiesen eine deutliche Kragenfaule auf, aus der sich der Pilz Athelia rolfsii (Curzi) C. C. Tu & Kimbr. (Anamorph: Sclerotium rolfsii Sacc.) isolieren lies. In einem Biotest wurde die Pathogenitat des Isolats an neun Malus Unterlagen gepruft. Fast alle Unterlagen erwiesen sich als anfallig, wenn die Inokulation in eine Wunde erfolgte. Aus der Faule lies sich A. rolfsii re-isolieren, womit die Koch’schen Postulate erfullt sind.