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The effect of arbuscular mycorrhiza, rice husk compost and biochar on Iranian borage Echium amoenum Fisch & C. A. Mey and post-harvesting soil properties
Get PDFIn einem Gewächshausversuch wurde der Einfluss von Bio-Düngern, wie vesikulär-arbuskulärer Mykorrhiza, Compost und Biochar aus Azolla-Algen auf Ertrag, Ertragsstruktur sowie die Aufnahme an Haupt- und Spurenelementen von iranischem Gurkenkraut geprüft. Gegenstand der Untersuchung war auch der Nährstoffgehalt der Böden nach der Ernte, sowie deren biologische Aktivität. Alle geprüften Behandlungen zeigten im Vergleich zu den Kontrollen signifikante Effekte auf Ertrag und Nährstoffaufnahme. Höhere Bodenatmung und eine höhere mikrobielle Biomasse indizieren eine Steigerung der Fruchtbarkeit der Böden durch die Behandlungen. DOI: 10.5073/JfK.2019.01.02, https://doi.org/10.5073/JfK.2019.01.02This study was conducted to investigate the effect of rice husk compost (RHC), rice husk biochar (RHB) and mycorrhization (MY) on some properties of Iranian Echium amoenum Fisch & C. A. Mey and also on some selected post-harvesting soil properties. A completely randomized design experiment was conducted with six treatments and six replications. Treatments comprised T1: control, T2: MY, T3: RHC, T4: RHB, T5: RHC + MY and T6: RHB + MY. Studied parameters included; shoot and root fresh weights, root and leaf length, shrub height, leaf number, shoot and root NPK content, shoot and root Fe, Zn, Cu and Mn concentration, root colonization percentage, soil NPK status, soil micronutrients concentrations, soil respiration and microbial biomass. Results revealed that application of RHC, RHB and MY individually or in combination with other treatments significantly affected studied parameters. In all cases except for root colonization, combined application (T5 and T6) had more satisfied impacts compared with a single application of treatments. DOI: 10.5073/JfK.2019.01.02, https://doi.org/10.5073/JfK.2019.01.0
Comparison of spectral indices to detect nitrogen uptake in winter wheat
Get PDFDie vorliegende Arbeit beschäftigte sich mit dem Einsatz von Spektralsensoren unter Verwendung von Spektralindices zur gezielten Erfassung der Stickstoffaufnahme bei Winterweizen (Triticum aestivum). Ziel war es, die Güte und die Genauigkeit bekannter Vegetationsindices zu quantifizieren und diese zu vergleichen. Darüber hinaus wurden für den Wellenlängenbereich 400 bis 900 nm in 2,8 nm-Schritten alle möglichen Zwei-Band-Indices errechnet und anhand von Korrelationsmatrizen deren Güte als Indikator für die Stickstoffversorgung beurteilt. Zu den Terminen EC 32, EC 39 und EC 65 wurden Spektralmessungen durchgeführt und anschließend ausgewertet. Zur Beurteilung der Qualität der Indices wurden parallel zu den Spektralmessungen destruktive Datenerhebungen an Pflanzenbeständen im Winterweizen durchgeführt. Zwischen der N-Aufnahme und den Indices PLSR, YARA_ALS und REIP_700 errechneten sich Bestimmtheitsmaße (R2) von bis zu 0,9.
Neben den R2-Werten wurde außerdem die Sättigung, also die Veränderung der Messwerte gegenüber der divergierenden Stickstoffaufnahme der Pflanzen ermittelt. Als Vegetationsindices mit besonders hoher Sättigung erwiesen sich der NDVI und der SAVI.The present work deals with the use of spectral sensors with spectral indices for the targeted detection of nitrogen uptake in winter wheat (Triticum aestivum). The aim was to quantify and compare the quality and accuracy of known vegetation indices. In addition, for the wavelength range 400 to 900 nm in 2.8 nm steps, all possible two-band indices were calculated and their quality was evaluated as an indicator for the nitrogen supply by means of correlation matrices. The spectral measurements were carried out at defined measurement data for EC 32, EC 39 and EC 65 and then evaluated. In order to assess the quality of the indices, destructive data collections on plant populations in winter wheat were carried out parallel to the spectral measurements. Between the N-record and the indices PLSR, YARA_ALS and REIP_700, coefficients of determination (R2) of up to 0.9 were calculated.
In addition to the R2 values, the saturation, i.e. the change in the measured values in comparison to the divergent nitrogen uptake of the plants, was also determined. Particularly high saturating vegetation indices were the NDVI and the SAVI
Clusters for the regional evaluation and analysis of pesticide use intensity (CEPI) in arable crops
Get PDFDie Analysen und regionalen Auswertungen der Intensität der Anwendung von Pflanzenschutzmitteln im Ackerbau im „Netz Vergleichsbetriebe Pflanzenschutz“ erfolgten bisher in Deutschland für die Großregionen Norden, Osten, Süden und Westen. Die Grundlage dafür bildeten die Boden-Klima-Räume. Allerdings ließen sich in den Großregionen die regionalen Spezifika oft nur unzureichend erklären. Deswegen wurde ein Vorschlag für eine neue Gebietsgliederung zur Berechnung regionaler Behandlungsindizes auf Grundlage der bestehenden Boden-Klima-Räume erarbeitet. Die Neugruppierung erfolgte anhand der geoklimatischen Hauptfaktoren für die Intensität der Anwendung von Pflanzenschutzmitteln. Mit einer Clusteranalyse wurden diese Faktoren aufgrund ihrer Ähnlichkeit gruppiert. Es entstanden acht Cluster, die hinsichtlich einer sinnvollen Anzahl von Erhebungsbetrieben pro Cluster für die Auswertung zu sechs Clustern für die regionale Erhebung und Analyse der Pflanzenschutzintensität (CEPI) im Ackerbau zusammengefasst wurden. Im Vergleich zu den Großregionen wird mit den CEPI eine bessere Aussagekraft zu regionalen Unterschieden der Behandlungsintensität erreicht. Regionale sowie jahresbedingte Unterschiede treten stärker hervor und ermöglichen somit eine valide wissenschaftliche Interpretation der Erhebungsergebnisse.To date, the analyses and regional evaluation of pesticide use intensity in arable crops in the Reference Farms Network were conducted based on the division of Germany into the large geographic regions, North, East, South and West. The soil-climate-areas formed the initial basis. The large geographic regions often explained only unsatisfactorily the regional specificities in the evaluation results. Hence, a new proposal was developed for a new regional spatial consolidation based on the existing soil-climate-areas. The geo-climatic key factors for pesticide use intensity served as attributes for the new consolidation of the soil-climate-areas. The factors were clustered based on their similarity in a cluster analysis. As a result of the cluster analysis eight clusters emerged and were merged to six clusters for regional evaluation and analysis of pesticide use intensity in arable crops (CEPI) after distributing the number of Reference Farms to the clusters and in order to enable a sound evaluation. The CEPI explain better the regional differences of the treatment index compared to the large geographic regions. Regional and annual differences are revealed more distinctively and enable a better scientific interpretation of the results
Stem starch reserves studied by on-solid reactions coupled with reflectance detections in water stressed grapevines
Get PDFWine grape is usually grown under water deficit conditions that could negatively impact plant reserves, including the organic carbon storage in perennial organs such as woody stems. Assessing the carbohydrate status in woody organs is therefore of interest as it can influence vegetative growth in the successive season. In this study, we aimed to apply an on-solid colour reaction (using Lugol\u27s iodine solution) coupled with reflectance spectroscopy detection to assess the grapevine canes\u27 starch accumulation in response to short drought periods. We used two Vitis vinifera cultivars (\u27Cabernet Sauvignon\u27 and \u27Syrah\u27) that were subjected to three different water conditions (well-watered; early water stress; late water stress) during the growing season as case study. We sampled woody stem tissue during winter rest. The results showed that water stress reduced the starch storage in \u27Syrah\u27, especially when imposed late and recovery time was not enough for carbon restoration, while \u27Cabernet Sauvignon\u27 was not affected. The results showed that the sensitivity of the method used here is adequate to assess starch accumulation differences due to drought treatments in grapevine canes. Moreover, the analytical approach appears fast, low cost, and promising for future physiological and agronomical research applications
Effects of living mulch on young vine growth and soil in a semi-arid vineyard
Get PDFAlthough the use of under-trellis plants as weed control (living mulch) in vineyards has been gaining popularity, its effects on soil quality and especially soil biology have not been well studied. Due to functional trait differences, plants may differ in how they compete with vines, and may also change abiotic and biotic soil properties. A living mulch trial was established in the semi-arid Okanagan valley of British Columbia comparing vine growth as well as soil abiotic and biotic outcomes for four living mulch treatments: buffalo grass (Bouteloua dactyloides), Chewing\u27s fescue (Festuca rubra ssp. commutata), birdsfoot trefoil (Lotus corniculatus), and shepherd\u27s purse (Capsella bursa-pastoris) with two industry standards: herbicide and cultivation. After two seasons, strong vine growth responses were seen that depended on living mulch identity, e.g., reduction in leaf N status with grasses, reduction in leaf water potential with the legume, birdsfoot trefoil. These effects were related to plant-induced changes to soil C:N ratio and soil moisture. Although treatments did not change abundance of the measured fungal guilds in bulk soil, abundance of arbuscular mycorrhizal fungi in vine roots was lowest with birdsfoot trefoil as living mulch. This study may help growers to select living mulch species appropriate for the soil conditions and resource availability of their site
Reproductive potential of the functionally female native Croatian grapevine \u27Grk bijeli\u27
Get PDFA native Croatian grapevine \u27Grk bijeli\u27, sharing a parent-offspring relationships with \u27Tribidrag\u27 (aka \u27Zinfandel\u27), is grown exclusively on the Adriatic island of Korčula. It is one of the grape cultivars with female-only functional flowers, causing reduced fertilisation and leads to problems in grape production and wine quality. A typical cluster of \u27Grk bijeli\u27 at maturity contains fully developed seeded berries, in addition to a highly variable proportion of undersized seedless berries. The aim of this study was to identify the cause of the reduced reproduction potential of \u27Grk bijeli\u27 in order to establish a better growing environment for improved yield and grape quality. \u27Grk bijeli\u27 female gametophyte develops normaly and at maturity contains both egg and central cell, together with two synergid cells and three antipodal cells. On the other hand, \u27Grk bijeli\u27 pollen grains show developmental deviations. Specifically, most of the pollen grains undergo the first pollen mitosis and contain one vegetative cell and one generative cell, while 20 % of ungerminating grains also accomplish the second pollen mitosis, giving rise to two sperm cells and one vegetative cell. Morover, \u27Grk bijeli\u27 pollen has acolporate morphology, which prevents germination and contributes to reduced reproduction. Furthermore, fertilisation after pollination with other varieties results in various degrees of ovule abortion depending on the pollinator, revealing Croatian cultivars \u27Plavac mali crni\u27 and \u27Pošip bijeli\u27 as favourable varieties. Although this study describes a highly valuable cultivar of local importance, it also contributes to fundamental knowledge of grapevine reproductive biology and offers a strategy for improvement of wine production and oenological performance of semi-fertile varieties in general
German Fruit Genebank – looking back 10 years after launching a national network for sustainable preservation of fruit genetic resources
Get PDFDas Nationale Fachprogramm zur Erhaltung und nachhaltigen Nutzung pflanzengenetischer Ressourcen landwirtschaftlicher und gartenbaulicher Kulturpflanzen ist die Arbeitsgrundlage aller Aktivitäten auf dem Gebiet der Erhaltung obstgenetischer Ressourcen in Deutschland. Die Erhaltung obstgenetischer Ressourcen, die in Deutschland bereits eine sehr lange Tradition hat und bis in die frühen Jahrzehnte des 20. Jahrhunderts zurückreicht, ist die Grundlage für eine langfristige Sicherung des Obstbaus. Bereits seit dieser Zeit wird eine Vielzahl an Sorten unterschiedlicher Obstarten in staatlichen und nichtstaatlichen Sammlungen erhalten. Die Deutsche Genbank Obst (DGO) wurde als dezentrales Netzwerk vor 10 Jahren mit dem Ziel gegründet, die Erhaltung verschiedener Sammlungen von genetischen Ressourcen zu koordinieren, um somit das Risiko eines Verlustes von Obstsorten zu minimieren. Die DGO besteht zum gegenwärtigen Zeitpunkt aus sechs obstartenspezifischen Netzwerken mit insgesamt 41 Sammlungen, die von Partnern sowohl an Bundes- und Landeseinrichtungen als auch in Landkreisen und Kommunen sowie von Vereinen und Privatpersonen erhalten werden. Da der Echtheitsüberprüfung der Obstsorten höchste Priorität beigemessen wird, war es in den letzten Jahren das Ziel, in den Sammlungen der Partner Bestimmungen der Sortenechtheit sowohl pomologisch als auch molekulargenetisch durchzuführen. 75% der Apfelsorten, die für die DGO ausgewählt wurden und ca. 60% der Kirschsorten konnten bisher als sortenecht bestimmt werden. Aufbauend auf diesen Ergebnissen wurde der erste Reiseraustausch zum Aufbau von Duplikaten in den Sammlungen organisiert, um das in den Kooperationsvereinbarungen gestellte Ziel, Erhaltung der Sorten an mindestens zwei verschiedenen Standorten mit jeweils mindestens zwei Bäumen, schrittweise zu erfüllen. Die Öffentlichkeitsdarstellung der DGO erfolgt über die Webseite www.deutsche-genbank-obst.de, wobei die Datenbank mit den Sorten- und Akzessionsdaten den Schwerpunkt des Internetauftrittes bildet. Zukünftig werden schrittweise Charakterisierungs- und Evaluierungsdaten sowie Fotos für alle Sorten der Sammlungen integriert. DOI: 10.5073/JfK.2019.02-03.01, https://doi.org/10.5073/JfK.2019.02-03.01In Germany, all activities of long-term preservation, utilization, research and development of fruit genetic resources are based on the German National Program for Genetic Resources of Agricultural and Horticultural Plants. The preservation of fruit genetic resources is the basis for ensuring a sustainable fruit production in Germany. It has a long-lasting tradition, which reaches back to the early decades of the 20th century. Ever since, a multitude of cultivars of different fruit crop species is preserved in public and private germplasm collections. The German Fruit Genebank has been established as a decentralized network 10 years ago aiming at the coordination of the different germplasm collections in Germany to minimize the risk of losing fruit genetic resources. The German Fruit Genebank is organized in species-specific networks. Currently, six of those networks consisting of 41 different collections are held at federal and state governmental institutions as well as in communities and towns, non-governmental organizations, and by private individuals. Because of high priority, the first projects characterizing the genetic resources on trueness-to-type based on pomological and molecular characters were completed in the last few years. About 75% of the apple cultivars belonging to German Fruit Genebank and ~60% of the cherry cultivars could be determined as true-to-type. Based on the results exchange of plant material will be organized between the partners of the German Fruit Genebank in order to duplicate the cultivars within the established fruit-specific networks and fulfil the aim of the cooperation agreement. The German Fruit Genebank is represented at the web site www.deutsche-genbank-obst.de, including the database of the cultivars and accession data as focal point. Data from systematic characterization and evaluation along with photographs will be uploaded for all the cultivars preserved in this decentralized network. DOI: 10.5073/JfK.2019.02-03.01, https://doi.org/10.5073/JfK.2019.02-03.0