20 research outputs found
Male and female reproductive success in natural and anthropogenic populations of Malaxis monophyllos (L.) Sw. (Orchidaceae)
In the presented study, male and female reproductive success was analyzed in relation to the population size, floral display and pollinators’ availability in natural and anthropogenic populations of the orchid Malaxis monophyllos (L.) Sw. Our results indicated significant differences between all investigated populations in parameters of floral display, including heights and number of flowers per inflorescence, as well the number of flowering individuals and their spatial structure. Additionally, populations differed both in male (pollinia removal) and female (fruit set) reproductive success, but only the fruit set clearly differentiated anthropogenic and natural populations. Despite the average flower number per plant being significantly higher in two of the anthropogenic populations, it was not related to the fruits set, which was significantly lower there. Moreover, our preliminary study concerning the potential pollinators of M. monophyllos showed a higher contribution of flies in natural habitats than in anthropogenic ones. Thus, we can suspect that the main factors influencing the level of female reproductive success in M. monophyllos populations are abundance of effective pollinators, as well as flower visitors, which may have resulted in a different level of pollen discounting in populations. Therefore, further studies concerning breeding system and pollination as important forces that shape demographic processes in M. monophyllos populations are necessary. Our results also indicate that suitable conservation methods in M. monophyllos should always include the preservation of potential pollinators, especially in these new, secondary habitats
What keeps "living dead" alive : demography of a small and isolated population of Maculinea (= Phengaris) alcon
Small and isolated populations are prone to future extinctions and thus
perceived as living dead'. Although generally considered to be of low
conservation value, their existence can still enhance species survival
at the landscape scale through improving the connectivity of other
populations and facilitating some (even if little) gene flow. We
investigated the demography and genetic status of a tiny and highly
isolated local population of Maculinea (=Phengaris) alcon near its
distribution margin with the aim of identifying the features that allow
it to persist. The study comprised intensive mark-recapture, surveys of
Gentiana pneumonanthe foodplants and butterfly eggs laid on them, as
well as genetic analyses. The population has been found to be
characterised by low genetic diversity and estimated at only a few tens
of individuals. The foodplant availability turned out to be the most
obvious factor limiting M. alcon abundance. Nevertheless, the life
expectancy of adult butterflies is fairly long, and their flight period
very short, implying that most individuals occur within the same time
window. Together with the relatively little protandry observed, i.e.
almost synchronous emergence of males and females, this increases the
chances of random mating among the individuals. Moreover, the
butterflies move freely across the core habitat fragment. All things
concerned, the effective population size is presumably not much lower
than the recorded population size. Our findings provide guidelines for
pinpointing those among "living dead" populations that are likely to be
the most persistent and thus worth conservation efforts aimed at
preserving them
The first record of the genus Phytodietus Gravenhorst, 1829 (Hymenoptera: Ichneumonidae: Tryphoninae) in Papua New Guinea, with description of a new species
AbstractThe genus Phytodietus Gravenhorst, 1829 is recorded from Papua New Guinea for the first time, based on a newly described species, P. (P.) guineus sp. nov. An identification key to the Australasian Phytodietus species is provided.http://zoobank.org/urn:lsid:zoobank.org:pub:D23507BB-F353-4CDE-AB12-2B1DBD4B5F2
The genus Phytodietus Gravenhorst, 1829 (Hymenoptera, Ichneumonidae Tryphoninae) in Kenya, with the description of a new species
Varga, Oleksandr, Kostro-Ambroziak, Agata (2020): The genus Phytodietus Gravenhorst, 1829 (Hymenoptera, Ichneumonidae Tryphoninae) in Kenya, with the description of a new species. Zootaxa 4778 (1): 196-200, DOI: https://doi.org/10.11646/zootaxa.4778.1.
First report of the genus Phytodietus Gravenhorst, 1829 (Hymenoptera: Ichneumonidae: Tryphoninae) from Thailand
Figure 5a -
Phytodietus pitambari:
head, facial view
A new species of Phytodietus Gravenhorst, 1829 (Hymenoptera: Ichneumonidae: Tryphoninae) from China
Kostro-Ambroziak, Agata, Zhou, Zichen, Reshchikov, Alexey (2020): A new species of Phytodietus Gravenhorst, 1829 (Hymenoptera: Ichneumonidae: Tryphoninae) from China. Zootaxa 4877 (2): 391-395, DOI: https://doi.org/10.11646/zootaxa.4877.2.1
Effect of Microencapsulation by Spray-Drying and Freeze-Drying Technique on the Antioxidant Properties of Blueberry (Vaccinium myrtillus) Juice Polyphenolic Compounds
Blueberry juice with high polyphenol concentration was spray- or freeze-dried using different coating materials: HP-β-cyclodextrin and β-cyclodextrin. The quality of the obtained powders was characterised by their anthocyanin content, total polyphenols and antioxidant capacity. SEM was used for monitoring structures and size (2–20 μm) of the microparticles. The losses of total phenolic compounds during spray-drying reached 76–78% on average, while these of anthocyanins about 57%. Freeze-dried powders showed better retention values of anthocyanins, which was about 1.5-fold higher than for the spray-dried counterparts. All blueberry preparations studied were characterised by very high radical scavenging activity
A broad spectrum of host plant responses to the actions of the gall midge: case study of Robinia pseudoacacia L. and Obolodiplosis robiniae (Haldeman)
Abstract This study aims to provide insights into plant-insect interaction during the formation and development of open gall structure on the leaves of Robinia pseudoacacia during gall formation by Obolodiplosis robiniae. This was the first time such far-reaching studies were performed at a biochemical and anatomical level. The gall wall is created from a few thick cells covered with epidermis. This parenchymatous nutritive tissue is rich in starch. Sclerenchyma only occurs around the vascular bundles as a result of the lignification of the parenchyma of the bundle sheaths. The level of reactive oxygen species (ROS) in the new structure was reduced and catalase activity was inhibited, which suggests another pathway of ROS decomposition – e.g. by ascorbate or glutathione peroxidase. The gall structure was combined with an increasing level of protein and non-protein thiols. Phenols seems to be a good protective factor; whose level was lower in infected leaflets. Levels of MUFA (monosaturated fatty acids) and SFA (saturated fatty acids) rose, probably as source of food for insects. The amount of fatty acid is positively correlated with the plant response. We detected that non infected leaflets produced C6:0 (hexanoic acid) and C8:0 (octanoic acid) fatty acids connected with odor. Changes in gall color as they develop are connected with photosynthetic pigments degradation (mainly chlorophylls) where the pathway of astaxanthin transformation to fatty acid is considered to be the most important process during gall maturation. Nutritive tissue is composed mainly of octadecanoic acid (C18:0) – a main source of food for O. robiniae
Struktura i właściwości lepkosprężystych pianek poliuretanowych napełnionych fusami kawy
The subject of the research presented in this article are viscoelastic polyurethane foams (VPF) made using a fillers from coffee grounds. The foams were made with varying content of coffee fillers. Foams and fillers were characterized by means of techniques such as infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry and cone calorimeter. The changes in the microstructure of the foams were analyzed using a scanning electron microscope. Foam properties in the compression test was assessed. As a result, it was concluded that the use filler from coffee grounds causes a significant reduction in compression set of foams after compression by 75% and by 90% of the height of the samples. It was shown that these changes are caused by changes in the chemical structure of the macromolecules of these foams but also in their structure. After addition the filler, all foams have permanent deformations with a value below the permissible limit of 10%. Addition of 20% by mass of filler caused by a decrease in the rate of heat release and the rate of smoke release during foam combustion.Przedstawiono wyniki badań lepkosprężystych pianek poliuretanowych (VPF) wytworzonych z dodatkiem różnych ilości fusów kawy. Pianki i napełniacz scharakteryzowano z zastosowaniem spektroskopii w podczerwieni, analizy termograwimetrycznej, różnicowej kalorymetrii skaningowej i kalorymetru stożkowego. Zmiany w strukturze pianek obserwowano metodą skaningowej mikroskopii elektronowej. Oceniono właściwości pianek w próbie ściskania. Stwierdzono, że napełniacz w postaci fusów kawy powoduje zmniejszenie odkształcenia trwałego pianek w próbie ściskania o 75% i zmniejszenie o 90% wysokości próbek, co jest wynikiem zmian w budowie makrocząsteczek pianek i w ich strukturze. Wprowadzenie 20% mas. napełniacza spowodowało zmniejszenie szybkości wydzielania ciepła i dymu w trakcie spalania pianek