@phdthesis{Biegert2023, author = {Biegert, Konni}, title = {"Smart Horticulture: Application of sensors and modelling to predict fruit growth, quality and storage behaviour of 'Braeburn' apples"}, volume = {2023}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-710}, school = {Hochschule Geisenheim University}, pages = {151}, year = {2023}, abstract = {Physiologische Lagerkrankheiten verursachen weltweit betr{\"a}chtliche wirtschaftliche Verluste bei einer Reihe von kommerziell wichtigen Kernobstsorten. Bei gleichen Lagerungsbedingungen bei derselben Sorte kann das Auftreten und die H{\"a}ufigkeit der Krankheiten in verschiedenen Jahren in einer Weise variieren, die durch eine Interaktion von Vorernte- und Nacherntefaktoren erkl{\"a}rt werden muss. Wesentliche bekannte Einflussgr{\"o}ßen sind Jahreswetterverlauf, Management in der Obstanlage, wie z.B. Blatt-Frucht Verh{\"a}ltnis, Calciumgehalt in den Fr{\"u}chten sowie Erntetermin und Lagerungsbedingungen. Bislang kann das Auftreten der Krankheiten jedoch nicht sicher vorhergesagt werden, um dadurch das Management in der Obstanlage oder im Lager entsprechend anzupassen. Analysen großer Datenmengen mithilfe K{\"u}nstlicher Intelligenz (KI) bieten neue M{\"o}glichkeiten unterschiedliche Datenarten und -s{\"a}tze zu verkn{\"u}pfen. Das Ziel der vorliegenden Arbeit ist die kleinr{\"a}umig und nicht-destruktive {\"U}berwachung der Fruchtentwicklung in der Obstanlage mit den oben genannten Managementmaßnahmen. KI Prognosemodelle wurden f{\"u}r die Sorte 'Braeburn' erstellt. 'Braeburn' ist anf{\"a}llig f{\"u}r physiologische Lagerkrankheiten, bei der im Fruchtfleisch oder unter der Schale Verbr{\"a}unungen auftreten. Mit zeltartigen Umbauungen {\"u}ber den Obstb{\"a}umen wurde die Temperatur in zwei fruchtphysiologisch wichtigen Perioden (Bl{\"u}tenblattabfall bis T-Stadium, drei Wochen vor der Ernte) erh{\"o}ht oder abgesenkt, um den Temperatureinfluss zu untersuchen. Unseres Wissens nach konnte dadurch zum ersten Mal in der Obstanlage {\"u}ber ausgewachsenen B{\"a}umen unterschiedliche Temperaturverl{\"a}ufe erzeugt werden. Dabei wurde ein positiver Einfluss auf die Reduzierung von inneren Verbr{\"a}unungen durch warme Nachttemperaturen (>10°C) vor der Ernte festgestellt. Insgesamt zeigte jedes Versuchsjahr unterschiedliche Auspr{\"a}gungen der physiologischen Fruchterkrankungen. Managementmaßnahmen und Witterungsbedingungen f{\"u}hrten zu signifikant unterschiedlichen Fruchtwachstumsverl{\"a}ufen und optischer nicht-destruktiver Punktspektroskopie. Die zweiw{\"o}chentlich wiederholten Spektroskopiemessungen an den gleichen markierten Fr{\"u}chten und deren Weiterverarbeitung in Partial Least Square Regression (PLSR) Modellen wurden einerseits auf ihre Genauigkeit {\"u}berpr{\"u}ft und zus{\"a}tzlich mit Modellen und Wetterdaten deren zuk{\"u}nftige Zust{\"a}nde vorhergesagt. Die statistische Auswertung der dreij{\"a}hrigen Daten zur n{\"o}tigen Probenanzahl und Fehler bei der destruktiven Trockensubstanz (TS) Analyse resultierte in Probenanzahlen von 100 St{\"u}ck pro Jahr, die eine Bandbreite von niedrigen bis hohen TS Werten umfassen m{\"u}ssen. Ein unbalancierter Laborfehler von 0.1-1 °Brix hat keinen Einfluss auf die modellierten TS Werte. Im Vergleich zur destruktiven TS Bestimmung im Labor konnte die Spektroskopie die TS im Mittel mit einer Abweichung von 0.5 °Brix bestimmen. Spektralmessungen in der Obstanlage nach einem Regenereignis f{\"u}hrten dabei zu keiner Ver{\"a}nderung im sichtbaren Spektralbereich. Jedoch k{\"o}nnen Kulturabdeckungen wie z.B. Regenschutzfolien {\"u}ber den Obstb{\"a}ume zu geringeren Wasserabsorptionswerten bei 975\,nm f{\"u}hren. Die Bereitststellung der Daten auf Baumsektor Ebene wurde in dieser Arbeit manuell durchgef{\"u}hrt. Jedoch wurden erste Schritte unternommen, um Fruchtwachstums- und Spektroskopiedaten per GPS Signal innerhalb einer Karte darzustellen. Die kleinr{\"a}umige Datenaufnahme auf Baumsektor Ebene ergaben f{\"u}r TS, Chlorophyll und Anthocyan Indexberechnungen, sowie auch f{\"u}r physiologische Krankheiten deutliche Unterschiede. Bei zuk{\"u}nftigen Forschungsarbeiten und Entscheidungsmodellierungen sollte dies ber{\"u}cksichtigt werden, auch wenn dies unter den gegebenen Umst{\"a}nden noch nicht voll-automatisiert umsetzbar ist. Das Prognosemodell zur Entstehung von physiologischen Krankheiten (Kernhausbr{\"a}une, Kavernen) konnte mit zweij{\"a}hrigen Daten die Entstehung der Lagerkrankheiten nach der Auslagerung und die Fruchtfleischfestigkeit zur Ernte in 90 \% der F{\"a}lle richtig vorhersagen. Somit konnte gezeigt werden, dass eine kleinr{\"a}umige Datenerhebung auf Baumsektor Ebene zur Prognose von physiologischen Lagerkrankheiten mithilfe KI Modellierungen angewendet werden kann. Weitere Forschungsarbeiten mit nicht-destruktiven Fruchtmessungen in der Obstanlage und dem Einfluss von Wetterbedingungen werden weitere Einblicke zur Qualit{\"a}tsverbesserung von {\"A}pfeln erm{\"o}glichen.}, language = {en} } @phdthesis{Boehm2020, author = {B{\"o}hm, Matthias}, title = {Wildunf{\"a}lle in Hessen - Ursachen, Schutzmaßnahmen und neue Konzepte -}, volume = {2021}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-330}, school = {Hochschule Geisenheim University}, pages = {470}, year = {2020}, abstract = {Wildunf{\"a}lle stellen deutschlandweit und insbesondere in waldreichen Bundesl{\"a}ndern wie Hessen zeitweise bis zu einem Drittel der Gesamtunf{\"a}lle dar. Im Mittelpunkt der vorliegenden Dissertation steht die folgende Forschungsfrage: Welche Parameter bestimmen die raum-zeitliche Verteilung von Wildunf{\"a}llen und wie k{\"o}nnen Entscheidungstr{\"a}ger aus Politik, Wirtschaft und Verb{\"a}nden aktuell und angesichts der technologischen Entwicklung eine bestm{\"o}gliche Senkung der Unfallzahlen herbeif{\"u}hren? In einem zweiteiligen Ansatz wird zun{\"a}chst eine Analyse der seitens der hessischen Polizei aufgenommenen Unfalldaten der Jahre 2006 bis 2016 durchgef{\"u}hrt, um Hypothesen zu den Einflussfaktoren zu beantworten. Aufbauend auf einem Forschungsprojekt der Bundesanstalt f{\"u}r Straßenwesen (BASt) werden die zehn gravierendsten hessischen Schwerpunktstrecken ermittelt und f{\"u}r diese eine Umfeldanalyse mit beh{\"o}rdlichen GIS-Daten durchgef{\"u}hrt. Die Ergebnisse werden mit den Werten von zufallsbasiert gew{\"a}hlten, unfallunauff{\"a}lligen Abschnitten verglichen. Weiterhin werden die o. g. {\"u}ber 170.000 Unfallreporte ausgewertet. Die Resultate der Analysen werden anhand der Fachliteratur mit dem aktuellen Stand der Forschung verglichen. Im zweiten Schritt wird die in die Unfallpr{\"a}ventionsarbeit involvierte Akteurslandschaft mittels Szenariotechniken zur Strategieentwicklung untersucht. Anhand der gewonnenen Erkenntnisse {\"u}ber die Dynamiken und Potenziale wird ein Handlungskonzept erarbeitet und mit Vertretern der Stakeholder diskutiert. Abschließend werden auf der Grundlage des in den beiden Arbeitsschritten gewonnenen Wissens Entscheidungsgrundlagen und Handlungsempfehlungen f{\"u}r die beteiligten Akteure erarbeitet. Den deutlichsten Einfluss auf das Unfallrisiko hat der Faktor D{\"a}mmerung, w{\"a}hrend der sich je nach Tierart bis zu zwanzigmal so viele Kollisionen als {\"u}ber vergleichbare Zeitspannen bei Tageslicht ereignen. In der Analyse der jahreszeitlichen Verteilung zeigen sich zudem deutliche Schwerpunkte w{\"a}hrend der Paarungszeiten und Revierk{\"a}mpfe. Hinsichtlich der Landschaftsmatrix f{\"u}hren erh{\"o}hte Anteile von Landwirtschafts- und Waldfl{\"a}chen nicht zwingend zu der Entstehung von Unfallschwerpunktstrecken, vielmehr muss die individuelle Komposition der {\"O}rtlichkeit untersucht werden. Die N{\"a}he von großen Fließgew{\"a}ssern und Seen hingegen bewirkt einen steigernden Einfluss auf die Unfallzahlen. Dichteunterschiede der Wildunfallh{\"a}ufigkeit je nach Tierart zeigen sich meist nur im gr{\"o}ßeren Maßstab; im Westen Hessens dominieren Reh-, im S{\"u}den Schwarzwildunf{\"a}lle. Die Unf{\"a}lle geschehen zu 70 \% m{\"a}nnlichen Fahrern, insbesondere in den Altersgruppen 20-24 sowie 45-50 Jahren. Insbesondere der Herbst bietet sich f{\"u}r Warnaktionen an, beispielsweise durch tempor{\"a}r aktivierte LED-Schilder. Bez{\"u}glich der effektivsten klassischen Gegenmaßnahme, dem Wildschutzzaun, besteht die Notwendigkeit zu einer besseren Datenhaltung der Beh{\"o}rden sowie einer Novellierung der Richtlinie zu den Einsatzkriterien f{\"u}r und der Konstruktion der Zaunsysteme. Die Prozesslandschaft zeichnet sich dadurch aus, dass die meisten Akteure nur wenig Initiative zeigen und gleichzeitig lediglich geringem Handlungsdruck unterliegen. Es bestehen keine Interessenskonflikte, sondern eher zeigt sich Synergiepotenzial. Zentral ist zuallererst, die haupts{\"a}chlich organisatorischen Aufgabenstellungen wie ein {\"u}bergeordnetes Großprojekt zu starten und eine zentrale Open-Data Meldeplattform einzurichten. Hier sind die Politik und Einrichtungen wie die Bundesanstalt f{\"u}r Straßenwesen gefordert. Nur mit ihrer Initiative k{\"o}nnen klassische Maßnahmen optimiert, innovative L{\"o}sungen in Kooperation mit der Automobilindustrie und IT-Dienstleistern eingef{\"u}hrt und das volle Potenzial der sich aktuell weiterentwickelnden Technologie zur Unfallpr{\"a}vention ausgesch{\"o}pft werden.}, language = {de} } @phdthesis{Stollberg2024, author = {Stollberg, Maren}, title = {Vertical planting design: The suitability and microclimatic effect of perennials in a textile living wall system.}, volume = {2024}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-924}, school = {Hochschule Geisenheim University}, pages = {I -- 211}, year = {2024}, abstract = {Urban green infrastructure has gained significant attention in the context of adaptation to climate change because of its positive effects. One approach to enhancing urban green infrastructure is through the use of Living walls (LW), also known as vertical greenery systems. While considerable knowledge and studies on traditional green facades already exist, there is limited information available on LW. Both green facades and LW are associated with numerous well-documented benefits (e.g., biodiversity and clean air), but these benefits depend on the functionality and vitality of the plants. Our knowledge of plants suitable for LW is limited to only a few climate zones and empirical values that lack confirmed validity. To address this gap, we conducted a three-year experiment using a novel, modular LW system on experimental walls exposed with different exposures. The aim of the research was to develop a textile-based, substrate-free Living Wall, which displays a perennial, attractive and diverse plant image and contributes to cooling. In this experiment, we documented the development of the plants, assessed their suitability, and measured the effect of the plants on the ambient temperature. The experiment took place over three years (2017-2019) in Geisenheim, Germany, which has a temperate oceanic climate and falls under the winter hardiness Zone 8a. For the LW system, we utilized a textile-based mat without soil (1 m²) and selected plants from wet/fresh habitats to enhance evaporative cooling. We maintained frequent irrigation with a nutrient solution, resulting in the mat being consistently overwatered. Based on common designs used in landscape architecture and on the conditions of wet habitats, we created three variants: one which was seeded: "Meadow" and two plant modules: "Cascade" and "Ground Cover". Together these modules consisted of 34 perennials and geophytes. Additionally, we sowed seed mixtures of over 30 species on the textile mat (Meadow/Seeding). We also included a Control group without plants, in which moss and weeds developed and were partially removed. After a pre-growing period on horizontal greenhouse tables, we placed the green mats vertically on experimental walls facing north, south, east, and west. Four replicates of each variant were randomly installed. We assessed plant development using various methods, including visual evaluation of aesthetics and growth form, height measurements, photographs, analysis of species coverage and visibility, canopy analysis, winter survival rate, biomass measurement, root position, and leaf area. Additionally, we employed temperature sensors and an infrared (IR) camera to measure the temperature effects of the plants on and of the ambient temperature under different setups. Through the experiment, we gained valuable insights into the techniques, cultivation, and maintenance of LW. Overall, we observed differences in plant development depending on the exposure, season, plant variant, and spontaneous vegetation. The tested plants exhibited a special vertical growth form and height. We noticed delayed growth on the north exposure, with complete coverage achieved in the third year. The south exposure showed particularly high growth, while the east and west exhibited similar but slightly lower growth compared to the south. The perennials retained their visual appearance throughout the year, with almost all variants looking attractive from May to September. Until the onset of winter, all variants had an appealing appearance. Unexpectedly, we observed the establishment of moss. Most plants survived the mild winters (2018/2019), although a cold winter (2017/1018) with a late frost resulted in damage and mortality for many plants. We conducted a detailed analysis of the different plant variants, as follows: The Ground cover variant exhibited an attractive appearance and foliage decoration throughout the year. At the east, west, and north exposures, the plants showed an attractive appearance shortly after winter, while on the south wall, it took until May for the species to start regrowing. In particular, Waldsteinia ternata displayed a nice leaf texture and, together with Pachysandra terminalis, was the most visually appealing. Ajuga tenorii 'Mauro', Alchemilla caucasica, Glechoma hederacea, and Geum coccineum 'Carlskaer' demonstrated beautiful ornamental effects and flowered during the summer. The Cascade variant showcased its attractiveness during the summer season, as most of the plants became less prominent during the winter. We observed that Tellima grandiflora 'Rubra' and Heuchera Hybrid 'Purple Petticoats' were the most visually appealing in this variant. Hosta sieboldii 'Harry van Trier' exhibited a pleasing ornamental effect and flowered during the summer. The ferns exhibited delayed growth but gradually developed a nice leaf texture. Self-settled moss complemented the planting, covering the entire mat. In the Meadow / Seeding variant, we observed increasing growth in height and vegetation coverage that extended from April to October. Initially, we sowed 32 different plant species, but only 10 were able to establish and become visible. These included Galium (album and palustre), Lycopus europaeus s. str., Stachys palustris, Anthoxanthum odoratum s. str., Festuca spp., and Poa spp. It is important to follow maintenance steps for the Meadow-LW. We noticed that the vegetation recovered within a few weeks after cutting. We recommend one complete cut during the summer and the removal of dead plant material after the frost period ends in spring. To examine the temperature effects of the plants on the ambient temperature and the climatic conditions to which they were exposed, we measured the temperature in different setups. The vegetation temperature depends on factors such as air temperature, measurement position, planting variant, and plant species. We observed a cooling effect only at a short distance from the LW, indicating a microclimatic impact. In conclusion, it is possible to effectively green a textile-based, soilless LW system. However, an automated irrigation system and regular monitoring and maintenance are essential. We identified suitable perennial species for each exposure and compiled a list of plants suitable for LW, along with their specific requirements. Seeded meadow-LW can easily be established. Furthermore, we recommend continuing our methodological approaches to obtain temperature measurements in LW in future studies.}, language = {mul} } @phdthesis{Hessdoerfer2015, author = {Heßd{\"o}rfer, Daniel}, title = {Untersuchungen zur kontinuierlichen Wasserpotentialmessung sowei des Einflusses verschiedener Tropfbew{\"a}sserungssysteme auf die generative und vegetative Wuchsleistung von Vitis vinifera (cv. Silvaner)}, volume = {2015}, edition = {1. Auflage}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-117}, school = {Hochschule Geisenheim University}, pages = {XV, 144 S.}, year = {2015}, abstract = {In den Jahren 2011 und 2012 wurde im Versuchsfeld am „Th{\"u}ngersheimer Scharlachberg" des Sachgebietes Weinbaumanagement der Bayerischen Landesanstalt f{\"u}r Weinbau und Gartenbau bei der Rebsorte Silvaner kontinuierlich das Wasserpotential mittels temperaturkorrigierter In-situ-Psychrometer gemessen. Ziel der durchgef{\"u}hrten Arbeiten war es, die Wasserpotentialdynamik von Reben an ihrem nat{\"u}rlichen Standort und die Pflanzenreaktion auf wechselnde Witterungseinfl{\"u}sse zu untersuchen. Zus{\"a}tzlich wurde die Ver{\"a}nderung der hydraulischen Leitf{\"a}higkeit der Gesamtpflanze bei unterschiedlichem Evaporationsanspruch und Bodenwasserstatus betrachtet. Die kontinuierliche Wasserpotentialmessung an Reben wurde in den Versuchsjahren am Rebstamm und an traubentragenden einj{\"a}hrigen Trieben durchgef{\"u}hrt. Dabei konnte festgestellt werden, dass sich das Messgewebe des Triebes besser eignet, um das Wasserpotential {\"u}ber einen l{\"a}ngeren Zeitraum kontinuierlich mittels In-situ-Psychrometer an Reben zu ermitteln. Anhand der Tagesg{\"a}nge ließen sich deutliche Beziehungen zwischen der Wasserpotentialdynamik und den verschiedenen Witterungsfaktoren feststellen. So hatten die beiden Faktoren VPD und Temperatur den gr{\"o}ßten Einfluss auf das Stammwasserpotential der Reben. Dementgegen wurde zwischen der Globalstrahlung und dem Stammwasserpotential kein Zusammenhang ermittelt. Der engste kurvilineare Zusammenhang wurde jedoch zwischen dem VPD und dem Wasserpotentialgradienten, der treibenden Kraft f{\"u}r den Transpirationsstrom der Pflanze, ermittelt. Der Einfluss des Bodenwasserstatus auf die Stammwasserpotentialdynamik der Reben war relativ gering. Große Unterschiede im Wasserpotentialverlauf des Tages wurden durch eine Rebenbew{\"a}sserung induziert. Demnach f{\"u}hrte der verbesserte Wasserstatus zu einem reduzierten Potentialgradienten der bew{\"a}sserten Reben zur Aufrechterhaltung der Transpiration im Vergleich zu den nicht bew{\"a}sserten Reben. In den Jahren 2011 bis 2013 wurde Exaktversuch zur Pr{\"u}fung der Auswirkungen einer Rebenbew{\"a}sserung mit bestimmten Bew{\"a}sserungsschwellenwerten durchgef{\"u}hrt. Ziel dieses Feldversuchs war es, den Einfluss verschiedener Bew{\"a}sserungsmethoden und Bew{\"a}sserungsintensit{\"a}ten auf die generative und vegetative Wuchsleistung der Rebsorte Silvaner zu untersuchen. Das versuchstechnisch vorgegebene Bew{\"a}sserungsmanagement der Varianten moderate {\"U}berflurbew{\"a}sserung, intensive {\"U}berflurbew{\"a}sserung, moderate Unterflurbew{\"a}sserung und intensive Unterflurbew{\"a}sserung wurde mittels des fr{\"u}hmorgendlichen Wasserpotentials exakt gesteuert. Gleichzeitig wurde innerhalb des Versuchsfeldes der Verlauf der Bodenfeuchtigkeit innerhalb der Kontrollvariante mittels der FDR-Technologie gemessen. Zus{\"a}tzlich wurde nach der Lese von jeder Variante das C12 / C13 Stabilisotopenverh{\"a}ltnis, der δ13C-Wert, im Mostzucker ermittelt. Um den Einfluss der verschiedenen Bew{\"a}sserungsintensit{\"a}ten und -methoden auf die generative und vegetative Wuchsleistung zu untersuchen, wurden die erzielten Traubenertr{\"a}ge, Mostgewichte (°Oe), Mosts{\"a}uren und Schnittholzertr{\"a}ge bestimmt. Der Bew{\"a}sserungsversuch zeigte auf, dass eine Zusatzbew{\"a}sserung bei der Rebsorte Silvaner einen starken Einfluss auf das vegetative Wachstum aus{\"u}bte und kein signifikanter Einfluss auf die erzielten Traubenertr{\"a}ge festzustellen war.}, language = {de} } @phdthesis{Muschkullus2023, author = {Muschkullus, Thomas}, title = {Umgang mit der Komplexit{\"a}t naturschutzrelevanter Großprojekte}, volume = {2023}, edition = {1. Auflage}, publisher = {Gesellschaft zur F{\"o}rderung der Hochschule Geisenheim}, address = {Geisenheim}, isbn = {13978-3-934742-90-1}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-664}, school = {Hochschule Geisenheim University}, pages = {507}, year = {2023}, abstract = {Großprojekte der Verkehrsinfrastruktur sind komplex und beeinflussen Schutzg{\"u}ter in hohem Maße; sie besitzen somit in aller Regel eine starke Relevanz f{\"u}r Ziele des Naturschutzes. Die Komplexit{\"a}t hat zur Folge, dass planerische Entscheidungen unter hohen Risiken und nicht dergestalt abgewogen werden, wie dies u.a. gem{\"a}ß dem Gesetz {\"u}ber die Umweltvertr{\"a}glichkeitspr{\"u}fung (UVPG) erforderlich ist. Die vorliegende Dissertation geht der Frage nach, wie mit dieser Komplexit{\"a}t umgegangen werden kann, um den Erfolg der Vorhaben zu optimieren.}, language = {de} } @phdthesis{Cotea2022, author = {Cotea, Victor}, title = {The removal of volatile phenols from Brettanomyces-contaminated wine using Molecularly Imprinted Polymers}, volume = {2022}, edition = {1. Auflage}, publisher = {Gesellschaft zur F{\"o}rderung der Hochschule Geisenheim}, address = {Geisenheim, Deutschland}, isbn = {13 978-3-934742-89-5}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-747}, school = {Hochschule Geisenheim University}, pages = {I -- 239}, year = {2022}, abstract = {Brettanomyces infections represent one of the major red wine quality spoilers affecting the industry worldwide and will most likely continue to be so in the years to come. When attempting to correct or "cure" a Brettanomyces tainted wine, the most problematic metabolites to be removed are volatile phenols, particularly 4-ethylphenol. Molecular imprinting represents one of the technologies which promise to bridge the gap between the precision and selectivity of chemical analytical methods for investigating liquid matrices, and that of industrial filtration and separation technologies currently in use. In this work, the removal of 4-ethylphenol from wine with the aid of molecularly imprinted polymers was studied. Overall, the materials investigated in this work show promise when investigated in lab-scale conditions with model solutions. They can be effective in treating wine if the treatment conditions are appropriate and involve multiple regeneration steps.}, language = {en} } @phdthesis{Brandt2021, author = {Brandt, Melanie}, title = {The influence of abiotic factors on the composition of berries, juice and wine in Vitis vinifera L. cv. Riesling}, volume = {2021}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-260}, school = {Hochschule Geisenheim University}, pages = {269}, year = {2021}, abstract = {Grapevine physiology and berry composition are highly influenced by abiotic factors, and this, in turn, affects wine composition and aroma. Primary metabolites, like sugars and acids, and also secondary metabolites, like phenols and terpenes, are sensitive to climatic conditions. However, the developmental stage of the berries and the environmental conditions within the bunch zone play a crucial role determining the different pathways of the metabolites and hence its concentration. This study aimed to investigate the influence of abiotic factors on the composition of berries, juice and wine of Vitis vinifera L. cv. Riesling. Field experiments were carried out in an experimental site of Hochschule Geisenheim University [Eibinger Magdalenenkreuz, Germany (49° 59'20'' N; 7° 55'56'' E)] using Riesling [clone 198-25Gm; grafted on rootstock SO4 Gm47 (Vitis berlandieri x V. riparia)]. In a non-irrigated vineyard, planted in 2007, the vines were trained to a vertical shoot position canopy system. The impact of global warming and rising temperature was one of the main questions of this thesis, and was simulated by an open heating system (OHS) in the vineyard. The tent-like construction passively heated the bunch zone. The effect of higher sun exposure on berries was trialed by the defoliation of the bunch zone at different stages of berry development. The removal of leaves around bunches is commonly used in coolclimate viticulture to improve the health status of berries and influence the aroma profile. Due to the increasing numbers of sunshine hours as well as the rising temperatures caused by climate change, the question then arises if in future defoliation practices will be the method of choice. Additionally, and in contrast, some bunches were placed in light-excluding boxes to simulate full shading. On days with high radiation, the open heating system clearly elevated temperatures compared to the control and the defoliation treatments. In the bunch zone above the open heating system, the air temperature was 4 °C higher compared to the other treatments. Inside the open heating system, the temperature was up to 13 °C higher. On days with low radiation, there was a minimal temperature difference between the treatments. The porosity of the bunch zone was quantified by a novel approach using lightsensitive films which provide a simple and accurate method for characterizing light conditions and quantifying cumulative radiation within the canopy. Different lightsensitive film qualities allow the measurement over a short period (3-7 days) or a more extended period (1-3 weeks). One of the significant advantages of this method will be that simultaneous measurement of several points will be possible. The health status of the berries was improved by defoliation and the infection (incidence and severity) of Botrytis cinerea reduced compared to the control providing a faster drying of bunches after morning dew or rainfall. Similarly, the OHS promoted airflow inside the bunch zone, causing same effects. Higher temperatures significantly reduced the berry weight, with the effect more pronounced if higher temperatures occurred before v{\´e}raison. Berries grown under higher temperatures showed lower total soluble solids and the glucose to fructose ratio was impacted by lower glucose concentrations. A change in the glucose to fructose ratio will be of relevance for the fermentation since most yeasts prefer glucose over fructose. Defoliation treatment had no impact on the total soluble solids. In contrast, intense radiation or shading did not affect the berry size while extreme shading of the bunches reduced total soluble solids. Tartaric acid was not significantly influenced by higher temperatures or radiation, but malic acid concentrations strongly declined under warmer conditions. This decreased the total acidity in juice and wine, which is of particular importance for the wine profile of Riesling. The defoliation practices showed only little effect on the acid concentrations whilst the extreme shading treatments strongly increased the acidity. The analysis of phenols in berry skin was performed by high-performance liquid chromatography (HPLC) coupled to a photodiode array (PDA) detector and quantified with an external calibration. Flavonols, in particular, were influenced by higher sun exposure, with significantly higher flavonol concentrations found in the defoliation treatments. The time point when defoliation was applied had only small effects on the final total flavonol concentration. On the other hand, when a sunny period occurred after v{\´e}raison flavanols revealed high concentrations after defoliation. Sunny periods before v{\´e}raison or a ripening period with low sunshine hours did not increase the flavanol concentration compared to the control. No impact of the defoliation on the group of hydroxycinnamic acids, non-flavanoids, was The sensory assessment with small scale-vinifications was diverse. Only in the younger vintage, the panellists were able to detect differences in wines, which were mainly based on total acidity. The influence of the treatments to the grapes, which were observed for primary and secondary metabolites in berries and juice, were found in wine as well. The only expectation was TDN. In wines, higher TDN concentrations were always detected for the late defoliation. The early defoliation contained higher TDN concentrations if a sunny period occurred before v{\´e}raison. Also, elevated temperatures caused higher TDN levels in wine. The prediction of the precise temperature and light conditions influencing TDN will require detailed investigations. A new approach was developed to analyse and quantify free and glycosidically bound monoterpenes and C13-norisoprenoids in berries, juice and wine. The sample volume was reduced by 90\% and free analytes were directly analysed from the matrix with only little sample preparation. This simplified the analysis, saved time and made the use of organic solvents and solid-phase extraction cartridges redundant. The method was validated and compared to other methods in literature. In juice and wine 15 monoterpenes and four C13-norisoprenoids could be analysed simultaneously and the typically concentration ranges of the samples were covered.}, language = {en} } @phdthesis{Grebneva2022, author = {Grebneva, Yevgeniya}, title = {The formation, sensory contribution and management of 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) in grapes and wines of Vitis vinifera L.cv. Riesling}, volume = {2022}, edition = {1. Auflage}, publisher = {Gesellschaft zur F{\"o}rderung der Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-387}, school = {Hochschule Geisenheim University}, pages = {220}, year = {2022}, abstract = {Wine from Vitis vinifera cv. Riesling grapes is one of the most internationally renowned white wine styles worldwide. There are several aroma compounds that are fundamental to the sensory properties of Riesling wines. Two such classes of compounds are monoterpenes and C13-norisoprenoids, both of which can be influenced in the vineyard, the winery and in the bottle. The overall objective of this study was to investigate the role of certain vineyard and winemaking practices on the development of sensorial important flavour compounds in Riesling, with particular emphasis on 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN). Chapter 2 investigates the effect of a manipulated light environment during grape ripening on Australian Riesling over two consecutive vintages. The application of coloured shade cloth was used to alter not only the quantity of light but also the quality of light reaching grape leaves and berries. Changes in both grape and wine composition were observed. A reduction solely in the quantity of light resulted in a significant reduction in free and total TDN concentrations. However, sensory descriptive analysis of finalised wines demonstrated a conflicting result, as increased 'kerosene-like' aroma (a common descriptor for TDN) was not always linked to higher TDN concentrations. The starting point of TDN formation is the availability of its precursors; carotenoids and their subsequent glycosylated breakdown products. Chapter 3 comprises the analysis of major grape carotenoids present in grapes under various light conditions. While several complex mechanisms involved in photosynthesis and notably the photoprotection triggered by different light qualities during the ripening period were observed, the reduction in concentration of carotenoids was significantly higher in sun-exposed samples compared to other treatments during grape ripening. The degree of carotenoid degradation could be a useful marker for the decision regarding TDN management in wine during winemaking or storage. Furthermore, Chapter 3 provides results from the analysis of C13-norisoprenoid glycosides in wines made from grapes grown under different shade cloth in correlation to their corresponding TDN concentrations. For this experiment two approaches were considered, firstly the untargeted profiling and then targeted analysis of the glycosides in wine. Glycosides related to TDN evolution in wine were tentatively identified. While trials conducted in Australia evaluated the effect of shading on the evolution of important grape and wine components in Riesling, Chapter 4 describes the significance of increased solar exposure (leaf removal) on Riesling grape and wine compositional behaviour in combination with different row orientations (East-West, Northeast-Southwest, North-South) under German field conditions. Microclimatically, East-West orientated rows maintained the lowest interior canopy light interception, Northeast-Southwest and North-South orientations lead to the highest light exposure values, peaking in the morning and afternoon, respectively. Pronounced differences in secondary metabolites were found between the different exposure levels introduced by leaf removal. Highly exposed grapes showed significantly higher bound and free TDN concentrations, however, no direct correlation was observed between elevated free TDN levels and the perception of 'kerosene-like' aroma in the wines. Finally, Chapter 5 comprises a comparative analysis of oenological practices of grape pressing and yeast selection including enzyme (β-glycosidase) addition on the extraction of TDN and related C13-norisoprenoids in finished wines. Insignificant differences were observed between the effect of whole-bunch and crushed/destemmed fruit pressings. While the choice of yeast during alcoholic fermentation did not affect TDN formation, the addition of glycosidases to musts resulted in an approximately 15\% to 25\% increases in free TDN concentrations after the wines were submitted to accelerated ageing. However, these changes were negligible when compared to the consequence of viticultural management practices. This thesis represents a valuable contribution to the understanding of the formation, management and sensory contribution of TDN in Riesling. Furthermore, this study investigated for the first time the effect of different light regimes (shade cloth) on TDN evolution which can be used to advance the management of Riesling grape production, especially during hotter summers.}, language = {en} } @phdthesis{Ponchon2024, author = {Ponchon, Mathilde}, title = {The entomopathogenic fungus Metarhizium robertsii and its endophytic potential in grapevine to regulate radicicole grape phylloxera populations}, volume = {2024}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim University}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-865}, school = {Hochschule Geisenheim University}, pages = {3 -- 212}, year = {2024}, abstract = {Grape phylloxera Daktulosphaira vitifoliae destroyed 30\% of the European vineyard by the end of the 19th century, attacking the woody roots of the grapevine Vitis vinifera (L.). To date, grafting grapevine on American resistant rootstocks is the leading solution to control the pest. However, grape phylloxera is present in most wine-growing soils and remains a threat in regions planted with non-grafted vines. Thus, alternative control solutions are investigated. The entomopathogenic fungus Metarhizium robertsii is known for its capacity to parasitize insects. Besides, the fungus can colonize plant rhizosphere and establish as an endophyte (i.e., within plant tissues) in many plant species. The thesis aimed to investigate if M. robertsii could persistently associate with the rhizosphere and as an endophyte in non-grafted grapevine V. vinifera without harming its growth while preventing the development of the grape phylloxera radicicole forms. Four M. robertsii strains native to four different vineyards were used and came from: i) the center-West Argentina (MsoilAR4.3), ii) the south of Australia (M224B), iii) the south-west of France (EF3.5(2)) and iv) the west of Germany (EF047). Greenhouse experiments were conducted to assess the association between M. robertsii and potted non-grafted grapevines. First, the comparison of the kinetic of grapevine rhizosphere and endosphere colonization was made, comparing the strain EF3.5(2) with a laboratory strain non-native to the vineyard (ARSEF-2575-GFP) to evaluate if a vineyard-native strain had a more durable colonization. Droplet Digital PCR (ddPCR), a culture-based method, and confocal imaging of root segments were used to characterize the associations. The strain EF3.5(2) had a higher establishment in the rhizosphere and root-endosphere of non-grafted grapevine than the strain ARSEF-2575-GFP. Both strains were established for up to 96-98 days post-inoculation (dpi) in both compartments. Then, the potential of association with the non-grafted grapevine of all four-vineyard native M. robertsii strains was compared. The rates of rhizospheric colonization at 68-70 dpi ranged from 60\% for the Argentinian MsoilAR4.3 strain, 65\% for the Australian M224B strain, 76\% for the French EF3.5(2) strain, to 100\% for the German EF047 strain. The rates of root endosphere colonization were 14\%, 10\%, 5\%, and 33\% at 68-70 dpi, respectively. No significant differences of rhizosphere and root-endosphere colonization between tested strains were recorded. Also, the fungal association unaffected the grapevine's growth and leaf pigment content during the experimental period. Finally, the effect of direct parasitism of the strain EF3.5(2) on the survival and development of radicicole grape phylloxera clone 'Pcr7' was evaluated in the woody root section bioassay. Depending on the method used to infect the insect, a significant reduction of 90 \%, 70 \%, and 86\% in survival probability was found, and 92\%, 89\%, and 93 \% in reduction of adults' development compared with control treatments. Also, the symptoms induced by grape phylloxera on non-grafted grapevines co-inoculated with M. robertsii were reduced by 91\% (mean of 4.8 ± 8.4 nodosities) compared with the phylloxera infested-plants (mean of 52.7 ± 50.7 nodosities). The qPCR analysis performed on grapevine inoculated with strain EF3.5(2) showed after 24h, the up- regulation of the VvWRKY-75, VvPR3.2, VvPR4, and VvG1, which are phylloxera-responsive defense genes involved in the resistance against phylloxera. In conclusion, M. robertsii's persistent association with non-grafted grapevine represents an alternative protection strategy against radicicole grape phylloxera, especially for wine-growing regions planted with non-grafted vines. Further field experiments should be carried out to determine the environmental factors affecting the effectiveness and persistence of M. robertsii associated with grapevine.}, language = {en} } @phdthesis{Wersebeckmann2024, author = {Wersebeckmann, Vera}, title = {Terracing in steep slope viticulture and its potential to promote biodiversity in vineyard ecosystems}, volume = {2024}, edition = {1. Auflage}, publisher = {Hochschule Geisenheim}, address = {Geisenheim}, url = {http://nbn-resolving.de/urn:nbn:de:hebis:2083-760}, school = {Hochschule Geisenheim University}, pages = {212}, year = {2024}, abstract = {A substantial area of the terrestrial surface is used for agricultural production. In Europe, many farmland species and ecosystems have evolved with traditional agricultural practices and rely on extensive cultivation for their survival. Today, agrobiodiversity is threatened by the abandonment of traditional agricultural land use. The cultivation of wine is one of the oldest forms of agriculture. On steep slopes, viticulture has shaped landscapes, cultural traditions, and unique ecosystems in many regions. In Germany, steep slope viticulture has been declining dramatically in recent decades due to insufficient profitability. The abandonment of these traditional cultural landscapes threatens the cultural heritage and the flora and fauna adapted to viticultural management. One solution to halt the decline of steep slope viticulture could be a change of cultivation system from vertically oriented rows to modern terraced vineyards. Here, the rows run parallel to the hillside, facilitating cultivation, and thus reducing production costs. At the same time, a large portion of terraced vineyard consists of uncultivated embankments, which can provide valuable habitats within the agricultural system. However, little is known about the effects of a cultivation system change and vineyard abandonment on biodiversity. In addition, information on how to sustainably revegetate terrace embankments is missing. Within the framework of this dissertation, the overall aim was to evaluate the potential of terraced vineyards to promote biodiversity and investigate measures for sustainable revegetation of terrace embankments. In addition, the effects of distinct vineyard management (vertically oriented vs. terraced) and vineyard abandonment on biodiversity were assessed. The main part of this thesis is based on a field study comparing three vineyard types (vertically oriented vineyard, terraced vineyard, abandoned vineyard) that were arranged in 15 triplets along the Upper Middle Rhine Valley (UMRV) in Germany. The effects of vineyard types, local vineyard parameters, and landscape structure on biodiversity were evaluated using four species groups. Studied groups represented plants and arthropod species (grasshoppers, wild bees, spiders). In a second field study, three newly constructed terrace embankments were revegetated using different seeding techniques and seed mixtures. In addition, measures to support plant establishment were evaluated. Plant establishment was assessed for three consecutive years in permanent vegetation plots. The first study on the three vineyard types revealed that there was no uniform positive effect of one vineyard type on all investigated groups. Instead, the responses were group and taxon-specific and driven by management-related disturbance intensities, local vegetation structures, soil and landscape structure. In total, the heterogeneous landscape and small-structured vineyard agroecosystem of the UMRV supported high species diversity, hosted high numbers of rare and threatened species, and diverse species communities across vineyard types. Plant species richness was enhanced by vineyard management and particularly benefited from terraced vineyards and rather nutrient-poor and extensively managed embankments. In comparison, plant communities of fallows were completely different with lower plant diversity. Grasshoppers were supported by vineyard management, and bare ground in vineyard inter-rows supported heat- and open-adapted species. Taller vegetation stands on terrace embankments enhanced grasshopper species richness while woody structures and vineyard abandonment reduced grasshopper diversity and abundance at the local and landscape scale. Wild bee species richness and abundance were strongly determined by their nesting needs. For ground-nesting bees, the suitability of soils for nesting was important, irrespective of vineyard management types whereas above-ground nesting bees were enhanced by woody structures of fallows at the local and landscape scale. Moreover, fallows further provided valuable floral and non-floral resources for both ground- and above-ground nesting bees. For spiders, there was no difference in species richness and abundance between vineyard types but many xerophilic species adapted to open habitat structures prevailed in terraced vineyards. Vineyard fallows supported highly distinct spider communities, including some late-successional species. In conclusion, the vineyard cultural landscape of the UMRV with both actively managed and abandoned vineyards led to a high diversity of plant and arthropod communities. Hence, for its preservation, a spatially heterogeneous landscape comprising both (semi) natural and viticultural-management elements is important. Results from the second study showed that terraced vineyards and especially terrace embankments can contribute to promoting biodiversity, especially if they are revegetated with regional seed mixtures. Seeds of locally adapted populations and hydro-seeding provided higher vegetation cover which is needed to prevent severe erosion whilst non-locally adapted standard seed mixtures and manual seeding had a higher failure risk and were more prone to severe precipitation events. Taken together, vineyard terracing appears to be a win-win solution for both winegrowers and biodiversity and thus helps to maintain viticulture on steep slopes.}, language = {en} }