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In vitro evaluation of berries of various Vitis genotypes for disease resistance to Botrytis cinerea
Get PDFBerries of 41 Vitis genotypes were evaluated for resistance to B. cinerea. Evaluation revealed that four genotypes were highly resistant (HR), eight resistant (R), eighteen susceptible (S) and eleven highly susceptible (HS). We further evaluated HR genotype \u27Dong fang zhi xing\u27 and HS genotype \u27Gold finger\u27 by comparing the fungal growth, reactive oxygen species (ROS) responses, jasmonic acid (JA) levels, anti-oxidants, e.g., Peroxidase (POD), Superoxide dismutase (SOD) and Malondialhydrate (MDA) content changes after infection with B. cinerea. Our results confirmed that the elevated resistance of \u27Dong fang zhi xing\u27 was due to weak fungal development, low ROS production, timely elevation of anti-oxidative functions, and high JA levels. Moreover, HS \u27Gold finger\u27 infection was severe and sustained ROS production which may be due to its relatively unchanged anti-oxidative activities and low JA level. Our results could help grape breeders to select suitable germplasm for future research work
VALOVITIS, the value of minority or endangered vine varieties in the Pyrenean foothills
Get PDFThe VALOVITIS project aims at improving the competitiveness of the wineries in the Pyrenean piedmont area through innovation and differentiation in a global market. During two consecutive harvests (2016-17), VALOVITIS monitored and characterised the agronomic behaviour of 20 grape varieties in the vineyards of the Germplasm Bank of the Government of Aragon in La Alfranca, Pastriz (Zaragoza). This work also assessed the technological and sensory properties of the wines produced following a basic winemaking protocol. Some of the varieties selected in this project, like the white variety \u27Greta\u27 and the red variety \u27Parrel\u27, showed a high potential to adapt to arid climates and to produce wines with a singular organoleptic profile
In situ immunofluorescence localization: A method for rapid detection of Beauveria spp. in the rhizosphere of Quercus robur saplings
Get PDFZur biologischen Bekämpfung von Pflanzenschädlingen, z.B. Maikäfer-Engerlingen, in der Rhizosphäre von Eichen, Apfelbäumen oder Kiefern werden zunehmend entomopathogene Beauveria-Spezies eingesetzt. Für eine erfolgreiche Anwendung ist es wichtig, die Ausbreitung und Persistenz der ausgebrachten Pilze qualitativ und quantitativ zu erfassen. Die Bestimmung beider Größen durch Ausplattieren auf selektiven Nährmedien oder durch molekulare Methoden wie PCR ist mühsam und oft ungenügend. Ziel der vorliegenden Studie war daher, eine spezifische In-situ-Methode durch Immunfluoreszenzmarkierung von Beauveria spp. zu entwickeln, hier an jungen Feinwurzeln dreijähriger Stieleichen. Durch Anfärben mit dem unspezifischen Farbstoff Blankophor wurde sichtbar, dass alle untersuchten Feinwurzeln ein dichtes Netz von Bodenpilzen trugen. Polyklonale Beauveria-Antikörper markierten an nicht beimpften Wurzeln keinen dieser natürlich wachsenden Pilze. Mit Beauveria brongniartii beimpfte Wurzeln zeigten bis zu zehn Monate nach der Inokulation eine spezifische Markierung. Während die natürlich vorkommenden Rhizosphären-Pilze in den Interzellularräumen der Wurzelrinde wuchsen, waren Hyphen von inokulierter B. brongniartii nie im Wurzelgewebe zu finden, sondern nur oberflächlich auf der Rhizodermis. Diese Beobachtungen zeigen, dass B. brongniartii bei Eichenwurzeln nicht endophytisch wächst, und dass die verwendete Methode die Unterscheidung von B. brongniartii von der in der Eichen-Rhizosphäre lebenden Pilzflora ermöglicht. Immunfluoreszenzmarkierung, wie in der aktuellen Studie eingesetzt, kann eine nützliche Methode sein, um B. brongniartii in der Rhizosphäre nachzuweisen und quantitativ zu erfassen und somit eine Langzeitkontrolle von Schädlingen mit Entomopathogenen zu ermöglichen.For biological control of plant pests, e.g. cockchafer grubs, in the rhizosphere of oak, apple or pine trees, entomopathogenic Beauveria spp. are increasingly applied. For successful use, it is important to monitor the spread and persistence of the inoculated fungi, both qualitatively and quantitatively. The determination of both parameters by plating on selective nutrient media or by molecular methods such as PCR of soil samples are quite laborious and often do not yield satisfactory results. Therefore, the aim of the present study was to develop a specific in situ method using immunofluorescence labelling of Beauveria spp. growing on young fine roots of three-year old oak saplings. All fine roots investigated were covered with a dense net of soil rhizosphere fungi, as visualized by staining with the nonspecific dye blankophor. On non-inoculated roots, polyclonal Beauveria antibodies did not label any of these naturally growing fungi. Only samples of roots inoculated with Beauveria brongniartii displayed specific labelling up to ten months after inoculation. Whereas the natural rhizosphere fungi were detected growing in the intercellular space of the root cortex in an ectomycorrhiza-like manner up to the endodermis, hyphae of the inoculated B. brongniartii were never seen within the root tissue but only growing on the surface of the rhizodermis. These observations indicate that B. brongniartii does not grow endophytically, and that the method used allows to discriminate B. brongniartii from the resident fungal flora in the oak tree rhizosphere. Detection by immunofluorescence labelling employed in the current study may be a useful tool to follow B. brongniartii in experiments aimed at establishing the entomopathogen in the rhizosphere and to monitor its fate in long-term control of entomopathogens
Annotations to the nomenclature of Monilia coryli
Get PDFDie als Monilia coryli benannte Monilia-Form an Haselnüssen muss gemäß nomenklatorischer Vorgaben mit ihrem sexuellen Stadium Ciboria coryli bezeichnet werden. DOI: 10.5073/JfK.2019.02-03.03, https://doi.org/10.5073/JfK.2019.02-03.03According to nomenclatural rules Monilia coryli, the Monilia of hazelnuts, is named after its sexual phase Ciboria coryli. DOI: 10.5073/JfK.2019.02-03.03, https://doi.org/10.5073/JfK.2019.02-03.0
Characterisation of different GLRaV-3 variant infections by determining virus concentration ratios and miRNA expression profiles
Get PDFGrapevine leafroll disease (GLD) is present in all grape-growing regions of the world and is considered the most significant grapevine viral disease. Grapevine leafroll-associated virus 3 (GLRaV-3) is considered the primary cause of GLD and in South African vineyards five genetic variant groups (I, II, III, VI and VII) have been confirmed. Biological distinctions between GLRaV-3 variants have not been fully validated. By characterising virus concentration and stress-responsive microRNA expression in GLRaV-3 infected plants, this study aimed to glean a better understanding of the possible biological distinctions between GLRaV-3 variants. Quantitative reverse transcription PCR was utilised for virus concentration ratio (VCR) determination and miRNA quantitation in GLRaV-3 positive and negative grapevines grown under greenhouse and field conditions. This study found statistically significant differences in VCRs in plants singly infected with different GLRaV-3 variants. Interestingly, no difference in mean VCRs were observed between data sets, despite notable differences in plant age, duration of GLRaV-3 infection, scion/rootstock combination and growing conditions. Several miRNAs showed statistically significant expression modulation between infected and healthy samples. miRNA expression between data sets varied substantially and a greater overall miRNA response was observed in plants with more established GLRaV-3 infections. The lack of significant differences in mean VCRs between data sets, coupled with the consistent modulation of certain miRNAs in plants that have likely been infected for longer is a promising result. This finding could indicate that successful inhibition of further virus replication by plant defence mechanisms occurred, and that these miRNAs are implicated in this response
Efficient identification, localization and quantification of grapevine inflorescences and flowers in unprepared field images using Fully Convolutional Networks
Get PDFYield and its prediction is one of the most important tasks in grapevine breeding purposes and vineyard management. Commonly, this trait is estimated manually right before harvest by extrapolation, which mostly is labor-intensive, destructive and inaccurate. In the present study an automated image-based workflow was developed for quantifying inflorescences and single flowers in unprepared field images of grapevines, i.e. no artificial background or light was applied. It is a novel approach for non-invasive, inexpensive and objective phenotyping with high-throughput.First, image regions depicting inflorescences were identified and localized. This was done by segmenting the images into the classes "inflorescence" and "non-inflorescence" using a Fully Convolutional Network (FCN). Efficient image segmentation hereby is the most challenging step regarding the small geometry and dense distribution of single flowers (several hundred single flowers per inflorescence), similar color of all plant organs in the fore- and background as well as the circumstance that only approximately 5 % of an image show inflorescences. The trained FCN achieved a mean Intersection Over Union (IOU) of 87.6 % on the test data set. Finally, single flowers were extracted from the "inflorescence"-areas using Circular Hough Transform. The flower extraction achieved a recall of 80.3 % and a precision of 70.7 % using the segmentation derived by the trained FCN model.Summarized, the presented approach is a promising strategy in order to predict yield potential automatically in the earliest stage of grapevine development which is applicable for objective monitoring and evaluations of breeding material, genetic repositories or commercial vineyards
