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Leaf yield, content and composition of the essential oil of Mentha x piperita L., Mentha x spicata L. and Mentha suaveolens EHRH.
Get PDFPyrrolizidine alkaloids in Senecio vulgaris L. depending on the stage of development, considering different seasons
Get PDFBiodiversity supporting properties of flaxseed cultivation (Linum usitatissimum L.) in agricultural landscapes
Get PDFLein ist die ökonomisch bedeutendste Arzneipflanze in Deutschland und wird auf einer Fläche von über 2500 ha kultiviert. Der durch seine Blüte produzierte Nektar und Pollen stellt möglicherweise eine potentielle Nahrungsquelle für Insekten in intensiv genutzten Agrarlandschaften dar. Um diese Hypothese zu prüfen, wurden blütenökologische Untersuchungen an Lein und in der Umgebung an drei Standorten durchgeführt und Artenlisten von blütenbesuchenden Insekten angefertigt. Der Fokus lag dabei auf den Ordnungen Hymenoptera (ausgenommen Formicidae) und Diptera. Zudem wurden Pollenproben von verschiedenen Wildbienenarten genommen und der Mageninhalt von Schwebfliegen auf das Vorhandensein von Leinpollen untersucht. An zwei der drei untersuchten Standorte waren im Lein mehr Arten anzutreffen als in benachbarten Umgebungsflächen. Alle drei Standorte wiesen in der Leinkultur mehr Individuen an der Ordnung Hymenoptera auf als die jeweilige Umgebung. Bei Vertretern der Gattung Halictus und der Art Lasioglossum calceatum konnte Leinpollen an den Sammelorganen nachgewiesen werden. Zudem wurde bei der Art Syrphus ribesii Leinpollen im Verdauungssystem gefunden. Außerdem zeigte sich, dass die Wildbienen Halictus sp. und Lasioglossum calceatum potentielle Bestäuber des Leins sind und dass der Lein als Nahrungsquelle von der Schwebfliege Syrphus ribesii intensiv genutzt wird.Flaxseed is the economically most important medicinal plant in Germany. It is cultivated on an area of over 2500 ha. Its pollen and/or nectar are a potential foodresource for insects in intensively used agricultural landscapes. To test this hypothesis insects on flowering flaxseed plants and the flowering environment were collected and the species and their abundance were determined. The study focused on taxa of Hymenoptera (except Formicidae) and Diptera. In addition, pollen samples were taken from wildbees and intestinal content of hoverflies was analyzed. On two out of three study sites we found higher species numbers in flaxseed than in the flowering environment. Further, more individuals of Hymenoptera were found in cultivated flaxseed compared to the neighboring environment on all three sites. Flaxseed pollen was found on Halictus sp. and Lasioglossum calceatum, indicating that these species may serve as pollinators of flax. Moreover, flaxseed pollen was found in the digestive system of Syrphus ribesii which suggests a potential role of flaxseed as a food source for this species
Influence of arbuscular mycorrhiza fungi, rice-husk-drived biochar and compost on dry matter yield, nutrients uptake and secondary metabolites responses of Iranian borage Echium amoenum Fisch & C. A. Mey
Get PDFIn einem Gewächshausversuch wurde der Einfluss von Bio-Düngern wie vesikulär-arbuskulärer Mykorrhiza, Biochar aus Reisspreu und Biokompost auf Ertrag, Nährstoffaufnahme und sekundäre Inhaltstoffe der Medizinalpflanze Echium amoneum; Fisch & C. A. Mey (iranisches Gurkenkraut) geprüft. Die Varianten waren komplett randomisiert. Alle Behandlungen zeigten signifikante Effekte auf Trockenmasse, Nährstoffaufnahme und Gehalte an Chlorophyll, Carotinoiden, Prolin, Anthocyanen, Flavonoiden, Schleimstoffen und Kohlenhydraten.This study was carried out to investigate the effect of bio-fertilizers including mycorrhiza (MY), rice husk compost (RHC), and biochar (RHB) on dry matter yield, nutrients uptake and some secondary metabolites of the medicinal plant Echium amoenum Fisch & C. A. Mey. The experiment was conducted in a completely randomized design and executed with six treatments and six replications. Treatments comprised of T1: control, T2: MY, T3: RHC, T4: RHB, T5: RHC+MY and T6: RHB+MY. The following parameters were studied: leaf dry weight, macro and micro nutrient uptake, chlorophyll a, chlorophyll b, carotenoids, proline, anthocyanin, flavonoid, mucilage and carbohydrate content. The results show that application of RHC, RHB and MY individually or in combination significantly affected the studied parameters in comparison with the control treatment. In all cases, combined application of bio-fertilizers together with mycorrhiza application (T5 and T6) had a more positive impact on the studied parameters compared to the application of each treatment alone
Effects of canopy architecture and microclimate on grapevine health in two training systems
Get PDFSemi minimal pruned hedge (SMPH) is a time and cost saving grapevine training system, which is becoming more and more popular in German viticulture. In this study we compared the canopy architecture and its effect on the microclimate of SMPH trained grapevines with those of plants trained in vertical shoot positioning (VSP). We detected a 3 % points higher humidity and a 0.9 °C lower mean temperature within the complex canopy architecture of SMPH trained vines compared to VSP. Moreover, we investigated the influence of the differing microclimate, canopy and bunch architecture, as well as berry skin characteristics of the two training systems on the incidence of the major fungal grapevine diseases Downy Mildew, Powdery Mildew and Botrytis Bunch Rot, as well as on the occurrence and damage of the invasive insect pest Drosophila suzukii. We demonstrate that SMPH trained vines can be more susceptible to Downy Mildew and Powdery Mildew than VSP trained vines. The incidence of Botrytis Bunch Rot can be higher in the latter system, even if berry skin characteristics are the same in both training systems. We trapped a higher number of D. suzukii in SMPH canopies, however no increased berry damage was observed. Based on our results we recommend a more adapted plant protection regime for SMPH trained vines due to their higher susceptibility to the major fungal diseases. Furthermore, we propose a combination of SMPH and fungal resistant grapevine cultivars, e.g. \u27Reberger\u27, to achieve a more competitive, environmentally friendly and high quality grapevine production
14-3-3 proteins from Vitis vinifera bind to and modulate the anthocyanidin synthase activity in vitro
Get PDF14-3-3 proteins are regulatory proteins that play a major role in a lot of important processes in plants, but their role in the regulation of the secondary metabolism is still poorly documented. For the first time, we demonstrated that the activity of ANS, an important enzyme of the flavonoid pathway, can be modulated in vitro by 14-3-3 proteins in grapevine
Portulaca oleracea L. (Purslane) extracts display antioxidant and hypoglycaemic effects
Get PDFPurslane (Portulaca oleracea L.) is a member of the family Portulacaceae. Due to its many health benefits, it is listed in a World Health Organization database. The aim of this work is to investigate the purslane extracts for their chemical profile and bioactivity.In this study, two different solvents (MeOH/H2O and EtOH) were applied to fresh and dried leaves. The extracts were analysed using HPLC-DAD. Phenolic acids (caffeic acid, p-coumaric acid and ferulic acid) and flavonoids (apigenin, kaempferol, luteolin, quercetin, isorhamnetin, kaempferol-3-O-glucoside and rutin) were identified in all samples. Quercetin and p-coumaric acid were the most abundant compounds. Total antioxidant activity was measured by using the ABTS and DPPH tests, and the ferric reducing antioxidant power (FRAP) assay. Hypoglycaemic properties were investigated via the inhibition of carbohydrate-hydrolysing enzymes, α-amylase and α-glucosidase.Fresh hydroalcoholic purslane extract exhibited the highest radical scavenging potential in both ABTS and DPPH test (IC50 values of 52.86 and 66.98 μg/mL, respectively), whereas dried hydroalcoholic purslane extract showed the highest α-glucosidase inhibitory potential (IC50 value of 45.05 μg/mL). Collectively these data show the health properties of this widely consumed salad plant
Analysis of nutritional composition and antioxidant activity of sweet potato (Ipomoea batatas L.) leaf and petiole
Get PDFTwo cultivars of sweet potatoes, Pumpkin and Chestnut, were planted in the didactic field of the Faculty of Horticulture, Craiova, and biochemical determinations were carried out from the blades and petioles of the leaves. This study highlights the antioxidant properties of these species, which are not well known in Romania, to encourage consumption of the vegetative parts of the plant, as well as use of the leaves in the future to develop natural antioxidants. The chlorophyll and carotene content in the blade and petiole were determined, highlighting the large amounts of petiole, depending on the cultivar. Catalase (CAT), peroxidase (POX), and vitamin C content, as well as total dry matter (TDM), reducing sugars, phenolic compounds, and antioxidant activity, were also measured. The petioles exhibited high antioxidant activity, with 62.186 μmol TE/g FW in Pumpkin and 95.168 μmol TE/g FW in Chestnut. The cultivars also exhibited differences at the blade level, with high values recorded for the Chestnut cultivar. Positive correlations between total polyphenols and reducing sugars (r = 0.89), antioxidant activity and reducing sugars (r = 0.48), and antioxidant activity and phenolic compounds (r = 0.53) were found. This study demonstrates that sweet potato leaves are a potential, inexpensive and beneficial source of natural antioxidants
Phytochemical characterization of Izote (Yucca elephantipes) flowers
Get PDFFlowers of the Izote (Yucca elephantipes) are traditionally consumed in different dishes in the Mexican cuisine. Although the use of the flowers in Salvador, Guatemala and México is quite popular, there are no scientific reports of their physicochemical properties and phytochemical composition of petals, carpels and stamens. As part of our research program on characterization of edible wild plants, we have analysed the composition and content of phenolic com-pounds in methanol crude extracts of petals, carpels and stamens from Y. elephantipes. The petals exhibited eighteen phenolic compounds, including 4-coumaric acid, rutin, ferulic acid, 4-hydroxybenzoic acid, caffeic acid, quercetin 3-glucoside, trans-cinnamic acid, among others. The principal phenolic compound found in petals, carpels and stamens was 4-coumaric acid, with 1154.20, 526.19 and 484.50 μg/g, respectively. In addition, carpel and petals were found to be rich in fatty acids, including linoleic, oleic, and palmitic acid. The petals also contained the highest amount of total dietary fiber. Based on these results, the flowers of Y. elephantipes appear to be a good source of phenolic compounds. This information may be useful in identifying these types of flowers and contribute in future research related to their use in the food area
