n this work the reaction of Nicotiana tabacum cv. Bright Yellow 2 cells on the presence of 500 μM zinc, 500 μM cadmium, 10 μM copper and 5 μM iron was studied. It was confirmed that all tested heavy metals induced in tobacco cell suspension culture early stress response manifested by increased production of hydrogen peroxide. The highest level of hydrogen peroxide was marked in samples containing cadmium ions. This metal was also the most toxic for tested plant material. Less toxic were ions of copper and zinc. Iron ions gave the weakest stress response (probably because of the plant cell peroxidase inhibition).
This study compares the soluble sugar content of zygotic and somatic pea embryos. It was noted that mature somatic embryos differed from zygotic embryos with respect to carbohydrate composition. Mature zygotic pea embryos contained glucose, myo-inositol, sucrose, maltose, galactinol, galactosyl-cyclitols, raffinose, stachyose and verbascose. The presence of maltose, galactosyl-cyclitols, stachyose and verbascose was not determined in somatic embryos, and their total soluble sugar content was below that of zygotic embryos. High sucrose levels in somatic embryos most probably resulted from the presence of sucrose in the growth medium. Monocotyledonous and irregular somatic embryos were characterized by a different sugar profile than regularly shaped somatic embryos and seeds.
Floristic research carried out in the region of Warmia and Mazury led to the discovery, on 16 May 2011, of a small cranberry stand in a forest, in a small raised bog with enclaves characteristic of transitional moors. The discussed stand is situated in the southern part of the Olsztyn Forest Division, district 499, in the vicinity of the eastern boundary of the Lake Kośno landscape reserve.
The effect of explant type on somatic embryogenesis induction in Pisum sativum (cv. Oskar and an unregistered line HM-6) was studied. Shoot apices, leaf primordia, and epicotyl fragments of axenically grown, etiolated seedlings, as well as embryonic axes and cotyledon fragments isolated from zygotic embryos at different stages of development, were used as explants. Somatic embryogenesis was induced essentially as described by Griga in 1998 – MS salts and sucrose, B5 Gamborg vitamins, picloram (2.5 μM). After induction period (14 days) all cultures were transferred to the differentiation medium (basal medium as above, auxin omitted). Both in Oskar and HM-6, only shoot apices developed somatic embryos and (with significantly lower frequency) adventitious shoots.
Generation of reactive oxygen species (ROS) constitutes an important first reaction under many stress conditions in plants. We demonstrate that Nicotiana tabacum L. cv. Bright Yellow 2 (TBY-2) cells in suspension cultures, generate superoxide radical and hydrogen peroxide upon treatment with cadmium and zinc. Addition of catalase and N,N-diethyldithiocarbamate (DDC) decreased the level of H₂O₂, whereas superoxide dismutase (SOD) induced a slight increase of the H₂O₂ production. The effects of catalase, DDC and SOD on the heavy metal-induced ROS production indicate that it occurs outside of the cells, and that at least part of the hydrogen peroxide is produced by dismutation of the superoxide radical (O₂⁻). The effect of pretreatment of the cell cultures with commonly used mammalian NADPH oxidase inhibitors was also tested. Strong inhibitions of cadmium and zinc-mediated ROS production were obtained with the flavoprotein inhibitors—diphenylene iodonium (DPI) and quinacrine and with an inhibitor of b-type cytochromes—imidazol. Membrane permeable-N-ethyl maleimide (NEM) and iodoacetate, and membrane non-permeable thiol reagents—para-chloromercuribenzoic acid (pCMBS) also inhibited the ROS production. These results suggested that the enzyme responsible for cadmium and zinc-induced ROS production in tobacco cells contains a flavocytochrome. They also show the importance of intra- and extracellular thiol groups in the observed stress reaction. The induction of ROS production with heavy metals showed properties comparable to the elicitor-induced oxidative burst in other plant cells.
Using the method described by GRIGA (1998), embryoids were obtained (through direct or indirect somatic embryogenesis) in cultures of shoot apical meristems of the following pea cultivars: Bankier, Dino, Hazard, Iłówiecki, Konserwowy IHAR, Kosynier, Makler, Oskar, Pegaz, as well as unregistered line HM-6. With cultivars Izolda and Lantra the efforts at somatic embryogenesis (SE) induction remained unsuccessful. The highest responsiveness to SE induction was observed (after 14 days of treatment with a relatively low concentration of picloram – 2.5 μM) in cultivars Oskar, Hazard and line HM-6, in which embryoids were formed with frequencies of 31, 15.9 and 12.5%, respectively. Increasing picloram level to 5 μM and extending period of induction to 28 days, it was possible to obtain SE efficiency above 10% in cultivars Konserwowy IHAR, Dino and Kosynier. Photoperiod affected SE efficiency and the degree and direction of this influence greatly depended on pea cultivar.
W trakcie badań florystycznych prowadzonych w gminie Purda na terenie województwa warmińsko- mazurskiego znaleziono nowe stanowisko chamedafne północnej Chamaedaphne calyculata (L.) Moench. Znajduje się ono na śródleśnym torfowisku wysokim, oddalonym o niecałe 2 km na południowy wschód od wsi Nerwik i o 2,5 km na północny wschód od wsi Giławy, na granicy oddziałów 224f i 238a, w Nadleśnictwie Wipsowo
Podczas badań florystycznych prowadzonych 18 sierpnia 2010 roku w południowej zatoce jeziora Serwent (gm. Purda, woj. warmińsko-mazurskie) stwierdzono występowanie grążela drobnego Nuphar pumila (Timm) DC. – rzadkiego gatunku należącego do reliktów glacjalnych – w postaci pięciu zwartych fitocenoz Nupharetum pumilae o powierzchni od 20 do 60 m2. Jest to jedyne, aktualnie potwierdzone stanowisko występowania tego gatunku w województwie warmińsko- -mazurskim
The paper presents detailed results of research into floristic and phytosociological studies on the vegetation of Olecko Wielkie Lake, carried out in 2009. During the study 28 hydrophytic taxa, 27helophytic taxa and 14 species classified as coexisting were identified, including of those forming the structure of particular plant communities. In total 69 plant taxa were found, without trees and shrubs growing on the lake shoreline. The paper presents the occurrence of protected, endangered, and rare species in Poland. The paper also presents a comparison of recent studies with does carriedout in the period in 1983–1986, allowing for the identification of changes in the flora and vegetationof Olecko Wielkie Lake between 1983 and 2009
In this work the effect of cadmium, copper, iron and zinc on antioxidant enzymes activity in Nicotiana tabacum Bright Yellow 2 cells derived from suspension culture was studied. It was noticed that all of tested elements stimulated the increase in superoxide dismutases activities and initial increment, followed by the decrease in catalase activity. Zinc ions in 500 μM concentration caused continuous raise and copper ions in 10 μM caused decrease in the activities of nonspecific peroxidases. The presence of cadmium ions in 500 μM concentration in reaction mixture caused the initial decrease followed by increase in phenol peroxidases activities. Iron ions in 5 μM concentration induced the enhance of nonspecific peroxidase activity after the third hour of exposition.
Heteromorphic achenes are formed within each capitulum of Galinsoga ciliata (Rafin) S.F. Blake. We examined (1) the effects of the duration of dry storage on germination and (2) the effect of burial in soil on viability and germination of heteromorphic diaspores. Fresh harvested peripheral achenes remained dormant, while central achenes germinated at 60%. Both achene types became non-dormant after one month of dry storage. In successive months of dry storage, peripheral achenes demonstrated a higher germination percentage than central achenes. The peripheral and central achenes showed similar temperature requirements during dry storage. A similar germination pattern was observed in both achene types, with a germination peak in March (96% of peripheral achenes at 12, 26 and 34oC; 90% of central achenes at 26 and 34oC). The germination capacity deteriorated over time. After 19 months of dry storage, both achene morphs failed to germinate at 12oC. At a 26o and 34oC, the same group of achenes continued to germinate at a relatively high level. After six and seven months of soil storage, 90-95% of both achene types remained alive. Dimorphic achenes were characterized by similar germination percentage (89-99%) at all temperature intervals, whereas peripheral achenes exhumed in May were the fastest to germinate. After 18 months of storage in soil (successive growing season), most of the harvested achenes were dead. The studied achenes did not form a permanent seed bank.
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