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Growth enhancing effects of banana homogenate on a glucomannan-rich orchid species: Serapias vomeracea (Burm.f.) Briq.
Get PDFGlukomannane sind pflanzliche Polymere, die hauptsächlich in der Lebensmittel- sowie in der pharmazeutischen und kosmetischen Industrie genutzt werden. Auf Grund der steigenden Nachfrage wurden in den letzten Jahren vermehrt wissenschaftliche Bemühungen unternommen, um eine landwirtschaftlich nachhaltige und ökologische Kultivierung glukomannanreicher Pflanzen zu entwickeln. Das Wurzelgeflecht der terrestrischen Orchideen ist eine reichhaltige Quelle für Glukomannan. Das Ziel dieser Arbeit war es den konzentrationsabhängigen Effekt von Bananen-Homogenat (BAN) auf die In-vitro-Entwicklung der glukomannanreichen Orchideenart Serapias vomeracea zu ermitteln. Die Keimungsrate war bei Nutzung des Kontrollmediums am höchsten. Die Zugabe von 10 g L–1 BAN zum Medium, sowohl mit als auch ohne Zugabe von Saccharose, führte allerdings zu einer statistisch sehr ähnlichen Keimungsrate. Allerdings führte die Zugabe von BAN in Abwesenheit von Saccharose in sämtlich getesteten Konzentrationen zu einer signifikant vermehrten Bildung von Protokormen. Die durchschnittlichen Spross- und Wurzellängen sowie die Anzahl der Wurzeln wurden bei einer BAN Konzentration von 30 g L–1 evaluiert. Die Knollenbildung und -entwicklung waren bei Zugabe von BAN leicht verbessert. Die Anzahl der Wurzelknollen von S. vomeracea und ihr Durchmesser waren bei Zugabe von 50 g L–1 BAN erhöht. Diese Studie legt nahe, dass BAN in der Produktion von glukomannanreichen Wurzelknollen für industrielle Zwecke genutzt werden könnte. Synthetische Pflanzenwachstumsregulatoren könnten im Zuge des nachhaltigen Anbaus von knollenbildenden Orchideen durch BAN ersetzt werden. BAN sollte weitergehend hinsichtlich seiner Eignung als Ersatz für Saccharose bei Studien zur In-vitro-Vermehrung mediterraner Orchideen untersucht werden.Glucomannan is a plant-sourced polymer used mainly in the food, pharmaceutical, and cosmetic industries. The increasing demand for the polymer makes researchers put effort into finding agriculturally sustainable and eco-friendly production methods for the source plants. The root systems of terrestrial orchids are rich sources of glucomannan. The objective of this research was to evaluate the concentration-dependent (10, 30, and 50 g L–1) effects of banana homogenate (BAN) on in vitro development of a glucomannan-rich orchid species, Serapias vomeracea. The control medium gave the highest seed germination rate. In contrast, the addition of 10 g L–1 BAN into the medium either in the presence or absence of sucrose gave statistically the same germination results with the control. However, all the BAN concentrations tested triggered protocorm formation significantly better in the absence of sucrose in the medium. The maximum mean shoot and root lengths, and root number were recorded after BAN treatments at 30 g L–1 concentration. The tuber formation and development were shown to be enhanced gradually due to BAN treatments. The successful tuberization in S. vomeracea roots was achieved after 50 g L–1 BAN, which gave more tubers in numbers with larger diameters. This study suggested that BAN could be used for tuber production for industrial demand. In the large-scale sustainable cultivation of tuberous orchids, synthetic plant growth regulators might be replaced by this natural additive. Also, BAN should be evaluated in in vitro propagation studies on Mediterranean terrestrial orchids as a substitute for sucrose
Union regulated non-quarantine pests (RNQPs) in the new legislation of the EU on Plant Health: Background and consequences
Get PDFDas seit dem 14. Dezember 2019 anzuwendende neue Pflanzengesundheitsrecht der EU (Verordnung (EU) 2016/2031) (EU, 2016) definiert erstmals die sogenannten „Unionsgeregelten Nicht-Quarantäneschädlinge“ (RNQPs). Damit erfolgt eine Anpassung des EU-Rechts an internationale Standards. RNQPs kommen im Gebiet der EU vor, sie werden hauptsächlich durch Pflanzen zum Anpflanzen verbreitet und es besteht die Einschätzung, dass sie inakzeptable wirtschaftliche Schäden bei der vorgesehenen Verwendung relevanten Pflanzenmaterials verursachen. Die für RNQPs getroffenen Maßnahmen in der EU zielen im Wesentlichen auf die Versorgung von professionellen Verwendern mit gesundem Saat- und Pflanzgut ab. Hierfür müssen spezifizierte Pflanzenarten bei Einfuhr und Verbringung innerhalb der EU frei von relevanten RNQPs sein oder vorgegebene Toleranzschwellen für einen Befall dürfen nicht überschritten werden. Für bestimmte RNQPs sind zusätzlich spezifische Anforderungen zur Verhütung des Auftretens während der Produktion einzuhalten. Anerkennungsstellen oder ermächtigte Pflanzenproduzenten bzw. -lieferanten attestieren die Konformität mit den Anforderungen durch den Pflanzenpass, der an entsprechenden Lieferungen angebracht sein muss. Amtliche Kontrollen sichern die Einhaltung der RNQP-Vorschriften.The new legislation on plant health of the EU that has been applicable since December 14, 2019 (Regulation (EU) 2016/2031) (EU, 2016) defines the so-called “Union regulated non-quarantine pests” (RNQPs) for the first time. This brings the EU legislation in line with international standards. RNQPs occur in the EU, they spread mainly by plants for planting and it is assumed, that they can cause unacceptable economic impact in respect of the intended use of relevant planting material. The measures in the EU for RNQPs essentially aim at the supply of professional users with healthy seeds and planting material. For this, specified plant species must be free of relevant RNQPs during import and movement within the EU, or defined tolerance thresholds for an infestation must be observed. For certain RNQPs, there are also specific requirements to prevent their presence during production. Certification agencies or authorised plant producers and traders certify conformity with the requirements through the plant passport, which must be attached to the corresponding deliveries. Official controls ensure compliance with the RNQP regulations
Accumulated data and results from the recent study of dsRNA isolated from grapevines used in experiments of insect and graft transmission of \u27Shiraz\u27 disease
Get PDFRT-PCR amplicons of dsRNA isolated from various grapevines, which were used in the experiments of transmission of \u27Shiraz\u27 disease (SD) from \u27Cinsaut Blanc\u27 clone P163/12 to SD-susceptible \u27Merlot\u27 and \u27Shiraz\u27 using mealybug Planococcus ficus and grafting were investigated. The amplicons were generated in RT-PCR based on virus-specific or random hexamers oligonucleotide primers. Standard molecular techniques and high-throughput sequencing (HTS), respectively, were applied. The results supported the hypothesis that GVA M5v variant present in \u27Cinsaut Blanc\u27 P163/12, which is a member of group II of GVA variants associated with SD, is crucial for developing this disease. HTS data did not reveal any other grapevine viruses besides GLRaV-3 and GVA in SD-affected grapevines, except for GVE which, however, was not present in all diseased plants
Evaluation of precooling temperature and 1-MCP treatment on quality of ‘Golden Delicious’ apple
Get PDFThe presented study simulates commercial practice and focuses on the effect of time gap between harvest and the beginning of cold storage. Apple fruit ʻGolden Delicious’ was harvested in Hungary and randomly separated into 3 groups for precooling at 1, 4 and 10 °C. After 7 d cold storage, groups were randomly split half to control and the other half was subjected to gaseous 1-methylcyclopropene (1-MCP) treatment for 24 h on their cold storage temperature (1, 4 and 10 °C). All samples were stored for 6 months at 1 °C followed by 7 d shelf-life at ambient temperature. Ethylene production, firmness, total soluble solid content, surface color and disorder incidence were determined. Significant correlation was found between color parameters hue and normalized green with firmness, SSC and ethylene production. Precooling temperature and 1-MCP treatment significantly affected apple quality (p < 0.01). Initial storage at 10 °C and application of 1-MCP on this temperature had no clear effect on maintaining fruit quality compared to control after 6 months storage. On the other hand, 1 °C and 4 °C precooling and applied 1-MCP treatment could slow the softening of samples during 6 months storage and in the following shelf-life. Apple quality was observed to change faster for group of 10 °C precooling and slower for groups of 1 °C and 4 °C. According to the results, precooling of apple fruit at 1 °C can be recommended in case the 1-MCP treatment is delayed
An endophytic fungus Aspergillus violaceofuscus can be used as heat stress adaptive tool for Glycine max L. and Helianthus annuus L.
Get PDFHigh temperature is one of the leading threats to the plants that severely affects crop quality as well as quantity. Endophytic fungi might be a new tool to safeguard crops against the perilous effects of global warming. In this context, we isolated a thermal stress mitigating endophytic fungus from the fern Dryopteris filix L. The phylogenetic study and 18S rRNA sequence similarity confirmed the potential strain as Aspergillus violaceofuscus. The culture filtrate of A. violaceofuscus exhibited higher concentration of secondary metabolites that enhanced the total chlorophyll content, plant height and biomass of sunflower and soybean seedlings under heat stress. Conversely, the A. violaceofuscus associated plants achieved low levels of reactive oxygen species, abscisic acid, catalase, ascorbic acid oxidase, proline and an overall improved the nutritional value. The current study suggests that A. violaceofuscus can be used as heat stress adaptive tool in crops to achieve sustainable agriculture
Estimation of daily carbon demand in sweet cherry (Prunus avium L.) production
Get PDFIn cherry production, the assimilate supply to the fruit is a crucial factor for growth and formation of quality parameters. The assimilate supply per fruit is limited by the relative growth capacity of trees, represented by the leaf area to fruit ratio (LA:F). In the present study, the required leaf area per fruit (LAdemand [cm² fruit-1]) of two sweet cherry cultivars, \u27Bellise\u27 and \u27Regina\u27, was estimated in 2018 and 2019, based on measured and interpolated values of fruit growth and fruit respiration rates. LAdemand changed daily with an overall increase during fruit development, showing average values in stage III in 2018 and 2019 of 139 cm² and 175 cm² in \u27Bellise\u27, while 199 cm² and 212 cm² were found in \u27Regina\u27, respectively. Estimated LAdemand for both cultivars was compared with measurements in cherries grown on girdled branches. In both years, estimated values exceeded measured values. In both years, positive correlation between LA:F and fresh mass, soluble solids content, and coloration was observed. The data obtained can be applied to evaluate the tree’s crop load for precise management
Experimental validation of an electronic counting device to determine flight activity of honey bees (Apis mellifera L.)
Get PDFEin Funktionsprototyp des Bienenzählers BeeCheck sollte in dieser Arbeit auf seine Genauigkeit hin überprüft werden, um seine Tauglichkeit für den wissenschaftlichen Einsatz zu validieren. Hierzu wurden zwei unterschiedliche Ansätze verfolgt: (i) Vergleich der elektronischen Daten des Zählgerätes durch Videoaufnahmen von Ein- und Ausflügen mit manueller Auswertung durch einen Beobachter sowie (ii) die Validierung mittels „Räubertest“ im bienendichten Zelt. Die Ergebnisse zeigten eine zu erwartende Temperatur Abhängigkeit der Flugaktivität sowie die Fehleranfälligkeit bei gewissen Aktivitäten am Flugloch. So waren unterschiedliche Geschwindigkeiten, sich entgegenkommende oder im Flugloch verharrende Bienen, sowie sich vor- und rückwärts bewegende Bienen eine Herausforderung für den Algorithmus, der aus den gemessenen Sensordaten die Bienentransaktionen ableitet. Um diese Grenzfälle zu minimieren und die Zählgenauigkeit zu erhöhen, ist es notwendig den Algorithmus entsprechend korrektiv anzupassen. Dies soll im Folgeprojekt „Etablierung digitaler Indikatoren der Bienenvitalität in Agrarlandschaften – V-I-Bee“ angegangen werden.In this work, a functional prototype of the BeeCheck counting device was evaluated for its accuracy to validate its suitability for scientific purposes. Two different approaches were applied: (i) we manually compared electronic data of the counting device by video recordings of entry and exit events, and (ii) by using the so-called “robber’s test” in a tunnel tent. The results showed an expected temperature dependency of the general flight activity. Difficulties occurred with certain activities at the hive entrance. The various running speeds of individuals, approaching or stuck bees, and bees moving back and forth in the tube were a challenge for sensor technology and the mathematical algorithm. To minimize such mistakes and to increase the counting accuracy, it is necessary to correct the algorithm accordingly. This will be addressed in the “V-I-Bee” follow-up project and future perspectives of using an improved counting device are discussed
