scholarly journals How Are the Flower Structure and Nectar Composition of the Generalistic Orchid Neottia ovata Adapted to a Wide Range of Pollinators?

2021 ◽  
Vol 22 (4) ◽  
pp. 2214
Author(s):  
Emilia Brzosko ◽  
Andrzej Bajguz ◽  
Magdalena Chmur ◽  
Justyna Burzyńska ◽  
Edyta Jermakowicz ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Hplc Method ◽  
Flower Morphology ◽  
Soil Parameters ◽  
Flower Structure ◽  
Pollination Syndromes ◽  
Wide Range ◽  
Flower Traits ◽  
Nectar Chemistry ◽  
Floral Displays

Plant-pollinator interactions significantly influence reproductive success (RS) and drive the evolution of pollination syndromes. In the context of RS, mainly the role of flower morphology is touched. The importance of nectar properties is less studied, despite its significance in pollination effectiveness. Therefore, the aim of this study was to test selection on flower morphology and nectar chemistry in the generalistic orchid Neottia ovata. In 2019–2020, we measured three floral displays and six flower traits, pollinaria removal (PR), female reproductive success (FRS), and determined the soil properties. The sugars and amino acids (AAs) were analyzed using the HPLC method. Data were analyzed using multiple statistical methods (boxplots, ternary plot, one-way ANOVA, Kruskal-Wallis test, and PCA). Variation of flower structure and nectar chemistry and their weak correlation with RS confirms the generalistic character of N. ovata. In particular populations, different traits were under selection. PR was high and similar in all populations in both years, while FRS was lower and varied among populations. Nectar was dominated by glucose, fructose, and included 28 AAs (Ala and Glu have the highest content). Sugars and AAs influenced mainly FRS. Among soil parameters, carbon and carbon:nitrogen ratio seems to be the most important in shaping flower structure and nectar chemistry.

scholarly journals Nectar Chemistry or Flower Morphology—What Is More Important for the Reproductive Success of Generalist Orchid Epipactis palustris in Natural and Anthropogenic Populations?

2021 ◽  
Vol 22 (22) ◽  
pp. 12164
Author(s):  
Emilia Brzosko ◽  
Andrzej Bajguz ◽  
Justyna Burzyńska ◽  
Magdalena Chmur
Keyword(s):  
Amino Acids ◽  
Reproductive Success ◽  
Natural Populations ◽  
Nectar Composition ◽  
Glucose Ratio ◽  
Wide Range ◽  
Flower Traits ◽  
Body Sizes ◽  
Nectar Chemistry ◽  
Epipactis Palustris

The aim of this study was to determine the level of reproductive success (RS) in natural and anthropogenic populations of generalist orchid Epipactis palustris and its dependence on flower structure and nectar composition, i.e., amino acids and sugars. We found that both pollinaria removal and female reproductive success were high and similar in all populations, despite differences in flower traits and nectar chemistry. Flower structures were weakly correlated with parameters of RS. Nectar traits were more important in shaping RS; although, we noted differentiated selection on nectar components in distinct populations. Individuals in natural populations produced nectar with a larger amount of sugars and amino acids. The sucrose to (fructose and glucose) ratio in natural populations was close to 1, while in anthropogenic ones, a clear domination of fructose and glucose was noted. Our results indicate that the flower traits and nectar composition of E. palustris reflect its generalist character and meet the requirements of a wide range of pollinators, differing according to body sizes, mouth apparatus, and dietary needs. Simultaneously, differentiation of nectar chemistry suggests a variation of pollinator assemblages in particular populations or domination of their some groups. To our knowledge, a comparison of nectar chemistry between natural and anthropogenic populations of orchids is reported for the first time in this paper.

Aflatoxins in peanut oil: food safety concerns

2018 ◽  
Vol 11 (1) ◽  
pp. 149-158 ◽  
Author(s):  
G.S. Shephard
Keyword(s):  
Food Safety ◽  
Fluorescence Detection ◽  
High Performance ◽  
Developing World ◽  
Degradation Products ◽  
Hplc Method ◽  
Peanut Oil ◽  
Official Method ◽  
Safety Concerns ◽  
Wide Range

Aflatoxins are widely recognised as important natural contaminants of a wide range of foods, including maize and peanuts (groundnuts), which form part of the staple diet in many countries of the developing world, especially in Africa. There is a frequent misconception based on solubility considerations and developed market surveys that aflatoxins do not occur in peanut oil. Thus, the use of peanut oil in human food is frequently overlooked as a source of aflatoxin exposure, yet artisanal oil extraction from contaminated peanuts in local facilities in the developing world results in carryover of these mycotoxins into the oil. Consequently, these peanut oils can have high contamination levels. This review highlights food safety concerns and addresses inter alia the analytical adaptations required to determine the polar aflatoxins in peanut oil. The determination of aflatoxins in peanut oil was first achieved by thin-layer chromatography, which was later mostly superseded by high-performance liquid chromatography (HPLC) with fluorescence detection, or later, by mass spectrometric detection. More recently, a specially modified HPLC method with immunoaffinity column clean-up and fluorescence detection has achieved official method status at AOAC International. In addition, the review deals with toxicology, occurrence and detoxification of contaminated oil. Although various methods have been reported for detoxification of peanut oil, the toxicity of degradation products, the removal of beneficial constituents and the effect on its organoleptic properties need to be considered. This review is intended to draw attention to this often overlooked area of food safety.

scholarly journals Chemical Basis of Floral Color Signals in Gesneriaceae: The Effect of Alternative Anthocyanin Pathways

2020 ◽  
Vol 11 ◽  
Author(s):  
Ezgi Ogutcen ◽  
Karine Durand ◽  
Marina Wolowski ◽  
Laura Clavijo ◽  
Catherine Graham ◽  
...  
Keyword(s):  
High Performance ◽  
Flower Color ◽  
Pollination Syndromes ◽  
Angiosperm Evolution ◽  
Ecological Diversification ◽  
Floral Color ◽  
Wide Range ◽  
Hummingbird Pollination ◽  
Color Signals ◽  
Physical And Chemical

Changes in floral pigmentation can have dramatic effects on angiosperm evolution by making flowers either attractive or inconspicuous to different pollinator groups. Flower color largely depends on the type and abundance of pigments produced in the petals, but it is still unclear whether similar color signals rely on same biosynthetic pathways and to which extent the activation of certain pathways influences the course of floral color evolution. To address these questions, we investigated the physical and chemical aspects of floral color in the Neotropical Gesnerioideae (ca. 1,200 spp.), in which two types of anthocyanins, hydroxyanthocyanins, and deoxyanthocyanins, have been recorded as floral pigments. Using spectrophotometry, we measured flower reflectance for over 150 species representing different clades and pollination syndromes. We analyzed these reflectance data to estimate how the Gesnerioideae flowers are perceived by bees and hummingbirds using the visual system models of these pollinators. Floral anthocyanins were further identified using high performance liquid chromatography coupled to mass spectrometry. We found that orange/red floral colors in Gesnerioideae are produced either by deoxyanthocyanins (e.g., apigenidin, luteolinidin) or hydroxyanthocyanins (e.g., pelargonidin). The presence of deoxyanthocyanins in several lineages suggests that the activation of the deoxyanthocyanin pathway has evolved multiple times in the Gesnerioideae. The hydroxyanthocyanin-producing flowers span a wide range of colors, which enables them to be discriminated by hummingbirds or bees. By contrast, color diversity among the deoxyanthocyanin-producing species is lower and mainly represented at longer wavelengths, which is in line with the hue discrimination optima for hummingbirds. These results indicate that Gesnerioideae have evolved two different biochemical mechanisms to generate orange/red flowers, which is associated with hummingbird pollination. Our findings also suggest that the activation of the deoxyanthocyanin pathway has restricted flower color diversification to orange/red hues, supporting the potential constraining role of this alternative biosynthetic pathway on the evolutionary outcome of phenotypical and ecological diversification.

Some investigations into soil and vegetation relationships associated with alkaline-saline soil surfaces in the Walcha area, Northern Tablelands, New South Wales

1995 ◽  
Vol 46 (1) ◽  
pp. 209 ◽  
Author(s):  
KH Kreeb ◽  
RDB Whalley ◽  
JL Charley
Keyword(s):  
Cynodon Dactylon ◽  
New South ◽  
New South Wales ◽  
Soil Surface ◽  
Tree Planting ◽  
Soil Parameters ◽  
Alkali Cations ◽  
Grazing Land ◽  
South Wales ◽  
Wide Range

The characteristics of the soil, vegetation and groundwater at a dryland salinity site on Miramoona, a property near Walcha on the Northern Tablelands of New South Wales, were investigated. Soil parameters measured at 23 points along a 200 m transect were highly correlated with the pattern of vegetation. Of overriding significance was soil pH, which varied from a high of over 10 on bare areas delineated by Critesion marinum and Cynodon dactylon to a low of less than 5 on grazing land supporting the growth of a wide range of pasture species. The bare areas were characterized by alkalinity. While they were sodic at all depths measured, they were only marginally saline and then only at the soil surface. The chemical composition of the groundwater collected from three piezometer tubes varied quite markedly over the site. It is hypothesized that the presence of alkaline bare areas on the Northern Tablelands is not a new problem, but rather the natural result of alternating wet and dry periods which have induced accumulation of carbonates and bicarbonates of the alkali cations, notably sodium. Drainage of the original perched swamps by the early landholders, tree clearing and the grazing of domestic livestock would have accelerated the process since European settlement. However, tree planting would appear unlikely to have any impact on the reclamation process in the short term. A more viable option would be the recreation of the original swamps in suitable situations, although this solution would create problems for grazing management.

Serotonin and its N-Acetylated and Acidic Derivatives in Insect Brain as Determined by High-Performance Liquid Chromatography with Electrochemical Detection

1993 ◽  
Vol 28 (1) ◽  
pp. 16-24 ◽  
Author(s):  
R. Vieira ◽  
M. Aldegunde
Keyword(s):  
Analytical Method ◽  
High Performance ◽  
Amperometric Detection ◽  
High Sensitivity ◽  
Hplc Method ◽  
Insect Brain ◽  
Oxidative Deamination ◽  
Wide Range ◽  
Hydrodynamic Voltammetry

The determination of serotonin (5-HT), N-acetylserotonin (NAS) and 5-hydroxy-3-indoleacetic acid (5-HIAA) in single brains of two acridids (Paracinema tricolor and Oedipoda caerulescens) was accomplished using a HPLC method combined with amperometric detection. A hydrodynamic voltammetry approach was used to assess the identity of each peak by comparing the voltammograms of standards and those of samples. The analytical method gave satisfactory reproducibility and sensitivity, and detected levels of 5-HT, NAS and 5-HIAA as low as 29, 55 and 10 fmol, respectively. This high sensitivity together with the simplicity of sample processing make the present analytical method suitable for a wide range of studies concerning indoleamine analyses in the insect nervous system. In both acridids, 5-HT showed the largest quantities, while its derivatives occurred in extremely low amounts. The results suggest that N-acetylation of 5-HT is quantitatively preferred to oxidative deamination in both species (NAS levels were 4-fold those of 5-HIAA). The relative importance of each catabolic pathway is discussed as related to physiological and genetic aspects.

scholarly journals Comparative predictions of discharge from an artificial catchment (Chicken Creek) using sparse data

2009 ◽  
Vol 13 (11) ◽  
pp. 2069-2094 ◽  
Author(s):  
H. M. Holländer ◽  
T. Blume ◽  
H. Bormann ◽  
W. Buytaert ◽  
G.B. Chirico ◽  
...  
Keyword(s):  
Soil Texture ◽  
Hydrological Cycle ◽  
Actual Evapotranspiration ◽  
Soil Parameters ◽  
Discharge Data ◽  
Sparse Vegetation ◽  
North East ◽  
Wide Range ◽  
A Minor ◽  
Coarse Soil

Abstract. Ten conceptually different models in predicting discharge from the artificial Chicken Creek catchment in North-East Germany were used for this study. Soil texture and topography data were given to the modellers, but discharge data was withheld. We compare the predictions with the measurements from the 6 ha catchment and discuss the conceptualization and parameterization of the models. The predictions vary in a wide range, e.g. with the predicted actual evapotranspiration ranging from 88 to 579 mm/y and the discharge from 19 to 346 mm/y. The predicted components of the hydrological cycle deviated systematically from the observations, which were not known to the modellers. Discharge was mainly predicted as subsurface discharge with little direct runoff. In reality, surface runoff was a major flow component despite the fairly coarse soil texture. The actual evapotranspiration (AET) and the ratio between actual and potential ET was systematically overestimated by nine of the ten models. None of the model simulations came even close to the observed water balance for the entire 3-year study period. The comparison indicates that the personal judgement of the modellers was a major source of the differences between the model results. The most important parameters to be presumed were the soil parameters and the initial soil-water content while plant parameterization had, in this particular case of sparse vegetation, only a minor influence on the results.

The behaviour of footings resting on a non-homogeneous soil mass with a crust. Part I. Strip footings

1981 ◽  
Vol 18 (2) ◽  
pp. 250-264 ◽  
Author(s):  
R. K. Rowe ◽  
J. R. Booker
Keyword(s):  
Soil Mass ◽  
Elastic Response ◽  
Soil Parameters ◽  
Wide Range ◽  
Weathered Crust ◽  
Homogeneous Soil ◽  
Finite Layer ◽  
Strip Footings ◽  
Underlying Soil

A convenient and economical finite layer method of analysing the behaviour of footings on a non-homogeneous soil is outlined. This method of analysis is used to investigate the elastic response of strip footings for a wide range of soil profiles involving a weathered crust overlying a main deposit. The stiffness of the crust is considered to be either constant or to decrease with depth while the stiffness of the underlying deposit increases with depth.The effect of layer depth, crust depth, and the rate of variation of stiffness within the crust and the underlying soil are examined. The influence of this non-homogeneity upon settlement profile, differential settlement, and consolidation settlement are discussed and the results obtained from this detailed analysis are compared with results obtained from the approximate use of existing homogeneous elastic solutions.The results of this study are presented in the form of influence charts which may be used in hand calculations to estimate the settlement of footings for a wide range of practical cases. The applicability of the solutions and the determination of soil parameters is briefly discussed.

scholarly journals Determination of Creep Properties of Clays from VRS Oedometer Tests

2019 ◽  
Vol 38 (2) ◽  
pp. 1857-1871 ◽  
Author(s):  
Tim Tapani Länsivaara
Keyword(s):  
Soft Clay ◽  
Complex Stress ◽  
Soil Parameters ◽  
Rate Variation ◽  
Additional Parameter ◽  
Creep Properties ◽  
Oedometer Test ◽  
Wide Range ◽  
Oedometer Tests

AbstractThe determination of creep properties still relies almost entirely on the incrementally loaded oedometer test introduced about 100 years ago. Although the simplicity of the test assures a robust evaluation of soil parameters, it also introduces some shortcomings like discontinuity of the evaluated parameters and the long duration of the test. In this study, the performance of the variable rate of strain (VRS) oedometer test for determination of creep properties of a sensitive soft clay is studied. The results from a comprehensive test series of VRS oedometer tests on a soft sensitive clay is presented. Three different setups for the strain rate variation were used, and each test was repeated thrice. The tests showed good consistency and yielded equal creep parameters compared to values from traditional incrementally loaded (IL) oedometer tests. The tests further verified that it is possible to describe the complex stress dependency of creep parameters with just one additional parameter to the primary deformation parameters. Compared to the IL tests, the VRS tests offers a faster determination and continuous creep properties for a wide range of stress.

scholarly journals Polyphenolic content and composition and antioxidative activity of different cocoa liquors

2009 ◽  
Vol 27 (No. 5) ◽  
pp. 330-337 ◽  
Author(s):  
I. Radojčić Redovniković ◽  
K. Delonga ◽  
S. Mazor ◽  
V. Dragović-Uzelac ◽  
M. Carić ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Hplc Method ◽  
Uv Spectra ◽  
Chemical Compositions ◽  
Nutritional Values ◽  
Wide Range ◽  
Polyphenolic Content ◽  
Caffeic Acid Derivative

Cocoa liquor used in the confectionery industry comes from a wide range of geographical areas and may have different chemical compositions, sensory properties, and nutritional values. We found it interesting to study the polyphenolic content and composition of cocoa liquors for their potential use in industrial production. Six defatted samples originating from different countries were extracted with aqueous methanol (70%, v/v), and the polyphenolic profiles were determined using RP-HPLC method. According to our results, all samples of cocoa liquors have similar polyphenolic profiles, however, quantitatively varied. In the samples, about 13 compounds were identified by comparison of their retention times and UV spectra, and the quantified peaks were (+)-catechin, (–)-epicatechin, (–)-gallocatechin, (–)-epigallocatechin, caffeic acid derivative, caffeine, and theobromine. Also, several peaks were identified as oligomeric procyanidins. The free-radical scavenging activity was determined by the DPPH• (1,1'-dipheny-2-picrylhydrazyl) and Oxygen Radical Antioxidant Capacity (ORAC) assays. The order of antioxidant activity of the cocoa liquors studied was the same with both methods (Madagascar > Mexico > Ecuador > Venezuela > Sao Tome > Ghana samples). In addition, correlation between the antioxidant capacity and polyphenolic content was also determined, a high correlation coefficient having been obtained by both methods (<i>R<sup>2<Isup> = 0.9868 for DPPH, and 0.9375 for ORAC).

scholarly journals Pollination syndromes in a Caatinga plant community in northeastern Brazil: seasonal availability of floral resources in different plant growth habits

2014 ◽  
Vol 74 (1) ◽  
pp. 62-71 ◽  
Author(s):  
ZGM Quirino ◽  
IC Machado
Keyword(s):  
Reproductive Success ◽  
Plant Growth ◽  
Rainy Season ◽  
Temporal Dynamics ◽  
Temporal Distribution ◽  
Northeastern Brazil ◽  
Floral Resources ◽  
Floral Traits ◽  
Pollination Syndromes ◽  
Growth Habits

To describe plant phenological patterns and correlate functioning for the quantity and quality of resources available for the pollinator, it is crucial to understand the temporal dynamics of biological communities. In this way, the pollination syndromes of 46 species with different growth habits (trees, shrubs, herbs, and vines) were examined in an area of Caatinga vegetation, northeastern Brazil (7° 28′ 45″ S and 36° 54′ 18″ W), during two years. Flowering was monitored monthly in all the species, over two years (from January 2003 to December 2004). Pollination syndromes were characterised based on floral traits such as size, colour, morphology, symmetry, floral resources, as well as on direct visual observation of floral visitors on focal plants and published information. We observed differences among the plant growth habits with respect to floral traits, types of resources offered, and floral syndromes. The flowering periods of the species varied among floral syndrome groups. The majority of the melittophilous species flowered during the rainy season in the two study years, while the species of the other pollination syndroms flowered at the end of the dry season. An asynchrony of flowering was noted among the chiropterophilous species, while the phalenophilous group concentrated during the rainy season. The overall availability of floral resources was different during the rainy and the dry seasons, and also it varied among plants with different growth habits. The availability of oil-flowers coincided with the period of low nectar availability. We observed a relationship between the temporal distribution of the pollination syndromes and the availability of floral resources among each growth habits in this tropical ecosystem. Resource allocation in seasonal environments, such as the Caatinga, can function as a strategy for maintaining pollinators, facilitating therefore the reproductive success of plant species. The availability of floral resources during all the year, specially in seasonal environments such as the Caatinga, may function as a strategy to maintain pollinator populations ensuring the reproductive success of the plants.

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