Abstract I.yen.da.ri.el'la. N.L. fem. n. Iyengariella , named in honor of MOP Iyengar, Indian phycologist. Cyanobacteria / Subsection V / Symphyonemataceae / Iyengariella The genus Iyengariella is characterized by true and false branching. It is a filamentous cyanobacterium, with true branching dichotomous, lateral, and less commonly pseudodichotomous and inverted V‐shaped true branching. The branches end with rounded apical cells or taper, ending with whip‐like extensions. Type species : Iyengariella tirupatienis Desikachary 1953, Figures 1–18. The genus is classified within the family: Symphyonemataceae Hoffmann, Komarek and Kaštovský 2005.
Abstract Geit.le'ri.a. N.L. fem. n. Geitleria , named in honor of Lothar Geitler (1899–1990), Austrian botanist and specialist in cyanobacteria. Cyanobacteria / Subsection V / Hapalosiphonaceae / Geitleria Geitleria is a filamentous cyanobacterium, with true branching of trichomes. Trichomes are embedded in gelatinous sheaths of extracellular polysaccharide (EPS), which are heavily calcified and permit growth and branching only at the tips of trichomes. Branching is dichotomous or V shaped and, less commonly, pseudodichotomous and lateral. All cells are interconnected by plasmodesmic pit connections. Type species : Geitleria calcarea Friedmann 1955.
AbstractNos.toch.op'sis. N.L. neut. n.Nostoc, a cyanobacterial genus; suff.‐opsis, similar to; from Gr. fem. n.opsis, aspect, appearance; N.L. fem. n.Nostochopsis, similar toNostoc.Cyanobacteria / Subsection V / Nostochopsidaceae / NostochopsisNostochopsisis a filamentous cyanobacterium with true branching (Subsection. V. in Rippka et al., 1979). The colonies are gelatinous, firm, and internally hollow. Trichomes are uniseriate with lateral T‐branches of two types: with unlimited and limited growth (1–3 cells), the latter with a terminal single‐pore heterocyst. Branch limited to a single cell that differentiates into a lateral heterocyst; intercalary heterocysts are less common.Type species:Nostochopsis lobatusWood ex Bornet and Flahault 1886, as originally described, was accepted and slightly modified by Geitler (1932, p. 475). The species name was corrected for gender by Komárek (2013, p. 546), so that in some sources it is entered asN. lobata. Nostochopsis lobatuswas collected in freshwater environments of Spain (Moreno et al., 2012), India, (Tiwari, 1978), Thailand (Thiamdao et al., 2012), and Argentina (Cáceres, 1973; Diaga et al., 2014). It was studied both using field‐collected and cultured materials; the growth was found to be modified depending on the culture conditions (Yamaguchi and Koketsu, 2016). The organism produced intercalary and more commonly terminal and lateral heterocysts.
Abstract Chlo.ro.gloe.op'sis. Gr. masc. adj. chloros , green; Gr. masc. n. gloios , sticky substance; Gr. fem. n. opsis , appearance; N.L. fem. n. Chlorogloeopsis , resembling Chlorogloea (Mitra 1950). Cyanobacteria / Subsection V / Chlorogloeopsidaceae / Chlorogloeopsis The genus Chlorogloeopsis Mitra et Pandey 1967 is a coccoid‐appearing, filamentous cyanobacterium (Subsection V in Rippka et al., 1979). The filamentous nature of this organism is unclear, except in the hormogonia. Hormogonia are composed of short chains of cylindrical or barrel‐shaped cells that, after ceasing motility, enlarge to become spherical. Colonies formed by three‐dimensional cell clusters. Heterocysts develop in both intercalary and terminal positions when levels of combined nitrogen are low. Hormogonia arise from cell aggregates. Vegetative cells enlarge to form akinetes . DNA G + C content (mol%) of the three studied strains ranges between 42.1 and 43.5, and the genome sizes from 4.7 to 5.4 × 10 9 Da (Rippka and Herdman, 1992). Type species : Chlorogloeopsis fritschii (Mitra 1950) Mitra and Pandey 1967 (some resources, e.g. Hindák 2008; Halder 2016, cite the same source as published in 1966).
Whiteflies are sap-sucking insects responsible for high economic losses. They colonize hundreds of plant species and cause direct feeding damage and indirect damage through transmission of devastating viruses. Modern agriculture has seen a history of invasive whitefly species and populations that expand to novel regions, bringing along fierce viruses. Control efforts are hindered by fast virus transmission, insecticide-resistant populations, and a wide host range which permits large natural reservoirs for whiteflies. Augmentative biocontrol by parasitoids while effective in suppressing high population densities in greenhouses falls short when it comes to preventing virus transmission and is ineffective in the open field. A potential source of much needed novel control strategies lays within a diverse community of whitefly endosymbionts. The idea to exploit endosymbionts for whitefly control is as old as identification of these bacteria, yet it still has not come to fruition. We review where our knowledge stands on the aspects of whitefly endosymbiont evolution, biology, metabolism, multitrophic interactions, and population dynamics. We show how these insights are bringing us closer to the goal of better integrated pest management strategies. Combining most up to date understanding of whitefly–endosymbiont interactions and recent technological advances, we discuss possibilities of disrupting and manipulating whitefly endosymbionts, as well as using them for pest control.
With the ongoing proliferation of satellite data, in particular open-access satellite imagery, from both optical and synthetic aperture radar (SAR) sensors, the number of downstream applications is rapidly growing. Developers of Earth Observation (EO)-based products and services, as well as expert and non-expert users of such tools, thus need access to a cloud computing infrastructure offering interoperable analysis functionality. Here, we present the versatility of such a cloud-based infrastructure called WASDI. WASDI, a web-advanced space development interface, is an online EO analytics platform where EO experts can develop and deploy applications (apps) and users can use them to processes satellite images on demand to generate value-added content.
Whiteflies are sap-sucking insects responsible for high economic losses. They colonize hundreds of plant species and cause direct feeding damage and indirect damage through transmission of devastating viruses. Modern agriculture has seen a history of invasive whitefly species and populations that expand to novel regions, bringing along fierce viruses. Control efforts are hindered by fast virus transmission, insecticide-resistant populations, and a wide host range which permits large natural reservoirs for whiteflies. Augmentative biocontrol by parasitoids while effective in suppressing high population densities in greenhouses falls short when it comes to preventing virus transmission and is ineffective in the open field. A potential source of much needed novel control strategies lays within a diverse community of whitefly endosymbionts. The idea to exploit endosymbionts for whitefly control is as old as identification of these bacteria, yet it still has not come to fruition. We review where our knowledge stands on the aspects of whitefly endosymbiont evolution, biology, metabolism, multitrophic interactions, and population dynamics. We show how these insights are bringing us closer to the goal of better integrated pest management strategies. Combining most up to date understanding of whitefly-endosymbiont interactions and recent technological advances, we discuss possibilities of disrupting and manipulating whitefly endosymbionts, as well as using them for pest control.
In precision agriculture, pesticides and other inputs shall be used precisely when (and where) they are needed. European Directive 2009/128/EC calls for respecting the principles of integrated pest management (IPM) in the member states. To clarify the question, when, for instance, fungicide use is needed, the well-established economic principle of IPM may be used. This principle says that pests shall be controlled when the costs of control correspond with the damage the pests will cause. Disease levels corresponding with the costs of control are referred to as control thresholds in IPM. Several models have been developed in plant pathology to predict when epidemics will occur, but hardly any of these models predicts a control threshold directly limiting their usefulness for answering the question when pest control is needed according to the principles of IPM. Previously, we quantified the temporal distance between critical rainfall periods and the breaking of the control threshold of Zymoseptoria tritici on winter wheat as being affected by temperature, based on data from 52 field experiments carried out in Luxembourg from 2005 to 2016. This knowledge was used to construct the ShIFT (SeptorIa ForecasT, https://shift.list.lu/ ) model, which has been validated using external data recorded between 2017 and 2019. Within the efficacy period of a systemic fungicide, the model allowed correct predictions in 84.6% of the cases, while 15.4% of the cases were predicted falsely. The average deviation between the observed and predicted dates of epidemic outbreaks was 0.62 ± 2.4 days with a maximum deviation of 19 days. The observed and predicted dates were closely correlated (r = 0.92, P < 0.0001). Apart from outliers, the forecast model tested here was reliable within the period of efficacy of current commercial fungicides.
The aim of the present investigations was to simulate the annual risk of bunch rot (Botrytis cinerea) on Vitis vinifera L. cv. Riesling grapes based on three long-term (n = 3 × 7 = 21 cases) assessment data sets originating from three Central European grape-growing regions. Periods when meteorological parameters were significantly (p < 0.01) correlated with the cumulative degree day (CDD7;18;24) reaching 5% disease severity were determined by Window Pane analysis. Analyses revealed five critical weather constellations ("events") influencing annual epidemics: relatively low temperatures after bud break, dry conditions during flowering, high temperatures after flowering, and low temperatures and high precipitation sums during/after veraison were all associated with thermal-temporal early epidemics. Meteorological data in each of the five events served as input for the bunch rot risk model "BotRisk." The multiple linear regression model resulted in an adjusted coefficient of determination (R2adj.) of 0.63. BotRisk enables (i) the simulation of the thermal-temporal position of the annual epidemic and, based on this, (ii) the classification of the annual bunch rot risk into three classes: low, medium, or high risk. According to leave-one-out cross-validation, 11 of 21 case studies were correctly classified. No systematic bias caused by location was observed, indicating that the transfer of the model into other locations with comparable climatic conditions could be possible. BotRisk (i) represents a novel viticultural decision support tool for crop cultural and chemical measures against bunch rot and (ii) enables an estimation of the bunch rot risk under changing environmental conditions.
Chemische Unkrautbekampfung wird aufgrund von okotoxikologischen Bedenken diskutiert. Um Landwirten zu helfen, die Ausbreitung von Unkrautern auch bei sinkender Verfugbarkeit von Herbiziden begrenzen zu konnen, wurden Projekte zu modifizierten Fruchtfolgen zur Reduzierung des Unkrautdruckes, digitale Ansatze fur bessere Entscheidungen zum Herbizideinsatz und zur besseren Integration von nicht-chemischen Unkrautbekampfungsmasnahmen begonnen. In einem ersten Monitoring in den Rapsbestanden Luxemburgs wurden relativ weit verbreitete Arten wie Stellaria media, Viola arvensis, Polygonum aviculare sowie Poa annua, Elymus repens, und Apera spica-venti gefunden. Chenopodium album wurde neben den im Fruhjahr keimenden Polygonum-Arten in moderater bis hoher Individuenzahl im Mais gefunden. Polygonum convolvulus wurde nach chemischer Bekampfung in hoher Dichte am Standort Kuborn gefunden, wohingegen C. album schlecht von mechanischen Methoden bekampft wurde. Alopecurus myosuroides-Pflanzen mit reifen Samen wurden nahezu ausschlieslich im Suden Luxemburgs gefunden. Alle 35 bislang getesteten A. myosuroides Samlingsproben waren resistent gegen Stomp® Aqua (mit dem K1 Hemmstoff Pendimethalin). Im Fall von Sigma® Maxx (mit den ALS-Inhibitoren Iodosulfuron+Mesosulfuron), waren jeweils 2 von 35 Proben sensitiv bzw. moderat resistent. 31 Proben waren resistent gegenuber Sigma® Maxx. 17 von 35 Proben waren sensitiv gegenuber Axial® (mit dem ACC-ase Inhibitor Pinoxaden), wahrend 18 Proben resistent gegenuber Axial® waren.
The low-input viticultural training system Semi-minimal pruned hedge' (SMPH) is progressively being more widely applied in the Central European grapegrowing regions. The present study examined the influence of (i) the training system (SMPH versus the vertical shoot position (VSP) system), (ii) the timing of shoot topping in SMPH, and (iii) the effects of mechanical thinning in SMPH on the bunch rot epidemic, grape maturity, and yield. Six-year field trials on Pinot blanc in Luxembourg demonstrated that yield levels in non-thinned SMPH treatments were 74% higher, and total soluble solids (TSS) at harvest 2.2 brix lower than in VSP. Non-thinned SMPH delayed the bunch rot epidemic and the maturity progress by 18 and 11 days compared to VSP, respectively. Different shoot-topping timings in SMPH did not affect the tested parameters. Mechanical thinning regimes reduced the yield by 28% (moderate thinning) and 53% (severe thinning) compared to non-thinned SMPH and increased TSS by 0.8 and 1.3 brix, respectively. Delayed bunch rot epidemic and maturity progress give rise to the opportunity for a longer maturity period in cooler conditions, making this system of particular interest in future, warmer climatic conditions. Providing that yield levels are managed properly, SMPH might represent an interesting climate change adaptation strategy.
Pesticide residues (112 compounds) were quantified by GC-MS/MS or LC-MS/MS in 85 bee bread samples and 154 pollen samples obtained from five apiaries each with three or four colonies (genotype Buckfast) in Luxembourg over the period 2011–2013. Thiacloprid, chlorfenvinphos, tebuconazole, and methiocarb were found most frequently in bee bread while thiacloprid, permethrin-cis, and permethrin-trans were detected most frequently in the pollen samples. Three neonicotinoid insecticides (clothianidin, imidacloprid, and thiamethoxam) that were restricted by an EU regulation in 2013 after our sampling campaign was finished were each found in less than 8% of the pollen or bee bread samples. The maximum concentrations of thiacloprid, metazachlor, and methiocarb measured in the pollen collected by a group of honeybee colonies (n = 5) without survivors within the 3-year period of observation were 86.20 ± 10.74 ng/g, 2.80 ± 1.26 ng/g, and below the limit of quantification, respectively. The maximum concentrations of the same compounds measured in the pollen collected by a group of honeybee colonies with significantly (P = 0.02) more survivors (7 out of 9) than expected, if the survivors had been distributed randomly among the groups of colonies, were 11.98 ± 2.28 ng/g, 0.44 ± 0.29 ng/g, and 8.49 ± 4.13 ng/g, respectively. No honeybee colony that gathered pollen containing more than 23 ng/g thiacloprid survived the 3-year project period. There was no statistically significant association between pesticide residues in the bee bread and the survival of the colonies. Actions already taken or planned and potential further actions to protect bees from exposure to pesticides are discussed.
Grape bunch rot caused by Botrytis cinerea is one of the major fungal diseases of grapevine (Vitis vinifera L.) worldwide. Besides crop cultural measures, botryticides are used on a regular basis for controlling bunch rot. To investigate the impact of (i) the time of application and (ii) the meteorological conditions on the efficacy of a single botryticide treatment per year (active ingredient: fenhexamid), field trials were conducted over a six year period (2011–2016) on the cultivars Riesling and Pinot gris. The median levels of efficacy compared to the untreated control at 100 days after growth stage BBCH 68 were 6.7%, 23.1%, 34.8%, 25.6%, 16.0%, 34.5% or 9.0% for Riesling and 13.9%, 16.5%, 23.7%, 9.8%, 6.6%, 9.3% or 14.1% for Pinot gris for applications at 0, 2, 4, 6, 8, 10 or 12 weeks after BBCH 68, respectively. Generally, the levels of efficacy as well as the delays of the epidemics caused by the fenhexamid treatment (i) were lower than those attainable by cultural measures and (ii) decreased with increasing temporal distance between BBCH 68 and the date of assessment as well as with the level of disease severity. Results indicate that in Riesling, fenhexamid treatments before bunch closure and shortly after veraison were most effective, whereas this was the case for Pinot gris only around bunch closure. The rather low overall efficacies suggest that a limited number of targeted botryticide applications may represent a facultative component in the complex bunch rot control strategy primarily based on efficient crop cultural measures. The delay of the epidemic induced by a single fenhexamid treatment was significantly affected by the annual meteorological conditions in the different stages of grape development even outside the application period suggesting that plant physiological factors also contribute to the overall effect.
Botrytis bunch rot is a major fungal disease of grapevines, and causes severe economic damage worldwide. Under humid climatic conditions, the development of bunch rot on grapes cannot be suppressed completely. Selection of planting material with lower bunch rot susceptibility represents one of the most efficient long-term tools in the complex bunch rot minimisation strategy. The present investigation conducted over four consecutive years (2013-2016) under the environmental conditions of the Moselle valley aimed at (i) detecting consistent differences in the bunch rot susceptibility within a group of nine commercially available Vitis vinifera L. 'White Riesling' clones, (ii) investigating potential underlying causes and (iii) deriving recommendations for 'Riesling' clone selection in practical viticulture. Disease severity and grape maturity (total soluble solids) progress could be well simulated by sigmoidal curves (R2 > 0.89; P < 0.038). On average of all four years, the dates when 5 % bunch rot disease severity were reached differed significantly by 9 days between the clone with the earliest epidemic (Trier 34) and the clone with the latest epidemic (Heinz 65). Multi-annual results enabled a classification of the nine clones according to (i) their relative bunch rot susceptibility as well as (ii) their relative precocity. Based on this, practical recommendations concerning a targeted clone selection as an integral long-term tool (i) in Integrated Pest Management contributing to pesticide reduction in viticulture as well as (ii) in the viticultural climate change adaptation strategy were derived.
Sets of treatments that were applied against varroa mites in the Luxembourgish beekeeper community were surveyed annually with a questionnaire between the winters 2010/11 and 2014/15. The average temperature and the precipitation sum of the month, when the respective varroa control method was applied were considered as co-variables when evaluating the efficacy of varroa control regimes. Success or failure of control regimes was evaluated based on the percentage of colonies lost per apiary in the winter following the treatment(s). Neither a positive nor a negative effect of formic acid (concentration 60%, w/v) on the colony losses could be found, irrespective of the weather conditions around the time of application. The higher concentration of 85% formic acid was linked with reduced colony losses when applications were done in August. Colony losses were reduced when Thymovar was applied in July or August, but applications in September were associated with increased losses compared with apiaries not treated with Thymovar during the same period. Apilife application in July as well as Apivar applications between July and September were associated with reduced colony losses. The removal of the drone brood and trickled oxalic acid application had beneficial effects when being done in April and December, respectively. Relatively warm (3.0 ± 1.3 °C) and wet (507.0 ± 38.6 mm/2 months) conditions during the winter months December and January and relatively cool (17.2 ± 1.4 °C average monthly temperature) and wet (110.8 ± 55.5 mm/month) conditions in July were associated with elevated honey bee colony losses.
Aims: The present analyses aimed at evaluating the performance of two models for estimating the overall effect of combining two or more measures (leaf removal, cluster division, late shoot topping, botryticide application, bioregulator application) for controlling grape bunch rot based on the efficacy of the individual measures.Methods and results: Field trials with the white Vitis vinifera cultivars Pinot gris and Riesling on the efficacy of three bunch rot control measures applied either alone or in combination were analyzed. Bunch rot disease severities prior to harvest were assessed and efficacies were calculated for each treatment. Observed efficacies of single measures were used to estimate the overall efficacies of all possible measure combinations. Calculated efficacies matched observed efficacies more accurately when assuming multiplicative interaction among the individual measures (R2 = 0.8574, p < 0.0001; average absolute deviation: 7.9%) than in case of assuming additive effects (R2 = 0.8280; average absolute deviation: 14.7%).Conclusions: The multiplicative approach assumes that each additional measure is affecting (in case of efficient measures: reducing) the disease severity level as the result of the additional treatments rather than compared to the disease severity level in the untreated control.Significance and impact of the study: The high goodness of fit as well as the observed low deviations between the estimated and the observed efficacies suggest that the multiplicative approach is appropriate for estimating the efficacy of combined viticultural measures in a complex practical bunch rot control strategy assembled of different modules.
Dietary carotenoid intake, especially from fruits and vegetables, has been associated with a reduced incidence of several chronic diseases. However, its bioavailability can vary, depending on the food matrix and host factors. Recently, it has been suggested that divalent minerals negatively impinge on carotenoid bioavailability by reducing bile-salt and non-esterified fatty-acid levels in the gut, which normally aid in emulsifying carotenoids. The aim of the present study was to investigate whether supplemental Ca would negatively influence carotenoid absorption in humans. A total of twenty-five healthy, non-obese men (age: 20-46 years, BMI<30 kg/m2) were recruited for this postprandial, randomised, crossover, double-blinded trial. Following a randomised block design, each participant received (after 2-week washout periods), on three occasions separated by 1 week, 270 g of spinach-based meals (8·61 (sd 1·08) mg carotenoids/100 g fresh weight), supplemented with 0, 500 or 1000 mg of Ca (as calcium carbonate), with each participant acting as his or her own control. Blood samples were collected at regular postprandial intervals for up to 10 h following test meal intake, and standardised lunches were served. TAG-rich lipoprotein fractions were separated and carotenoid concentrations determined. AUC for meals without supplemented Ca were 22·72 (sem 2·78) nmol×h/l (lutein), 0·19 (sem 3·90) nmol×h/l (β-carotene) and 2·80 (sem 1·75) nmol×h/l (β-cryptoxanthin). No significant influence of supplementation with either 500 or 1000 mg of supplemental Ca was found. In conclusion, Ca - the most abundant divalent mineral in the diet - given at high but physiological concentrations, does not appear to have repercussions on the bioavailability of carotenoids from a spinach-based meal.
Magnesium may reduce carotenoid bioavailability by forming insoluble complexes with bile salts/fatty acids, inhibiting micelle formation. Here, we investigated whether altering bile/pancreatin concentration influenced potential negative effects of magnesium on carotenoid bioaccessibility. Spinach (4g) was digested in vitro with added magnesium (0, 200, 400mg/L) and canola oil/coffee creamer, at varying bile extract (1 or 8mM) and pancreatin (100 or 990mg/L) concentrations. Bioaccessibility was determined for β-carotene, lutein, and total carotenoids via HPLC. Additionally, lipolysis, particle size, and zeta potential of the micellar fractions were investigated. Increasing magnesium concentrations negatively affected carotenoid bioaccessibility (p<0.001), lipolysis, particle size and zeta potential. The impact of magnesium on carotenoid bioaccessibility was modulated mainly by bile concentration, with samples digested with 1mM of bile being more susceptible to inhibitory effects of magnesium than those digested with 8mM (p<0.001). Thus, magnesium was found to potentially interfere with carotenoid bioaccessibility at various physiologically plausible conditions.