Adaptive responses to high salinity of two subspecies of Aster tripolium on different nitrogen sources

The effects of NaCl salinity, different N-sources (nitrate or ammonium), as well as pH on the major enzymes of N-metabolism and total antioxidant capacity were investigated in two subspecies of Aster tripolium L., A. tripolium ssp. tripolium, a maritime halophyte, and A. tripolium ssp. pannonicus, endemic on the continental alkaline salty meadows. Differences in their biochemical and physiological responses to the experimental conditions are in agreement with their evolutional adaptation either to the fluctuating coastal circumstances or to the more constant salinity level on the alkaline salty meadows. Accordingly, A. tripolium ssp. tripolium reacted more sensitively to salinity while A. tripolium ssp. pannonicus showed less physiological flexibility and more stable performance

Adaptive responses to high salinity of two subspecies of Aster tripolium on different nitrogen sources

ABSTRACT The effects of NaCl salinity, different N-sources (nitrate or ammonium), as well as pH on the major enzymes of N-metabolism and total antioxidant capacity were investigated in two subspecies of Aster tripolium L., A. tripolium ssp. tripolium, a maritime halophyte, and A. tripolium ssp. pannonicus, endemic on the continental alkaline salty meadows. Differences in their biochemical and physiological responses to the experimental conditions are in agreement with their evolutional adaptation either to the fluctuating coastal circumstances or to the more constant salinity level on the alkaline salty meadows. Accordingly, A. tripolium ssp. tripolium reacted more sensitively to salinity while A. tripolium ssp. pannonicus showed less physiological flexibility and more stable performance. Soil salinity is an important agricultural problem. One possible way to use affected fields is planting salt tolerant crops such as Aster tripolium L.. Aster tripolium (Asteraceae/Compositae) is a typical halophyte species with two horizontally isolated subspecies (Borhidi 1995). The two subspecies are very different concerning their habitats, morphology and physiology. The ssp. tripolium is a maritime halophyte, while ssp. pannonicus is common on the continental alkaline salty meadows. Morphological differences are obvious in leaf size and shape, leaf colour, leaf number and growth habitus. Both ssp. accumulate inorganic ions even at low external concentrations. Physiologically sea aster was more intensively studied (Shennan et al. 1987ab) because of its recently increasing commercial importance as halophyte crop. Its value is the mild salty taste and high protein content of the succulent leaves. The ssp. pannonicus inhabits salty meadows rich in NaHCO 3 thus having high pH. Materials and Methods Two subspecies of Aster tripolium were examined in our experiments: ssp. tripolium and ssp. pannonicus. Plants were grown hydroponically in complete modified Hoagland nutrient solution of different pH values (from 4 to 10). In one container, 7 plants of each of the subspecies were placed and were grown for 6 weeks under controlled conditions in greenhouse at an additional light intensity of 100 µmol m -2 s -1 for 12 hours. Day/night temperature was 24/18ºC. The pH values were controlled and adjusted daily by addition of HCl or NaOH. On the basis of protein content data (Bradford 1976), pH 5 and 8 were selected for further experiments when plants were grown at 0, 50, 100, 200 and 300 mM NaCl concentrations added to the complete nutrient solution. The nutrient solutions also altered in there nitrogen source which was nitrate or ammonium, respectively. Chlorophyll Results and Discussion Aster tripolium ssp. tripolium obviously suffered under low salt conditions combined with high pH values as shown by the low pigment concentrations. In both subspecies, qualitative and quantitative alterations were observed in protein concentrations with increasing salinity and pH values. At low pH and medium salt concentrations, ssp. tripolium had higher protein levels than ssp. pannonicus, while at high pH values ssp. pannonicus had higher performance. Very high Na + concentrations were accumulated in the leaves in both pH regions. Calcium is known to play a special role in tolerance under salinity. Surprisingly, in ssp. pannonicus Ca 2+ accumulation increased under the highest NaCl concentrations (300 mM) while in contrast, ssp. tripolium showed a decreasing tendency in calcium accumulation under increasing external salinity. In the following pH 5 was selected and the nitrogen source was nitrate or ammonium, respectively. Our intention was to investigate enzymes involved in nitrogen metabolism as a function of sodium concentration. Nitrate reductase (NR), glutamine synthetase (GS) activity and total antioxidant capacity were measured in both leaves and roots. Control (0), 10, 50, 100 and 200 mM NaCl was added to the nutrient solutions with both nitrogen sources. One of our interesting results was that young leaves of Aster tripolium ssp. tripoliu

"Telepesek" és "szabadok". Társadalomtörténeti és történeti ökológiai tanulmányok = Inside and Outside of the Labor Camps

1. Munkaterv szerinti statisztikai elemzések a "Táborlakók és családjaik" c. kérdőíves kutatás és a táborokban készült névsorlisták társadalomstatisztikai adatai alapján. Életút-elemzések. Az elemzések eredményeként tanulmányok írása és egy szerkesztett tanulmánykötet kéziratának összeállítása 2. A témakör egységes fogalmi bázisának kialakítása - lexikon-szócikkek 3. Terepmunka a kitelepítés legfőbb merítő bázisán: az 1950-ben különleges igazgatási övezetté nyilvánított jugoszláviai és ausztriai határövezetekben. Terepmunka a kitelepítés célterületén: az alföldi pusztákon létrehozott tizenkét zárt kényszermunkatábor helyszínein és környezetében. Az egykori táborrendszer társadalom- és tájtörténeti rekonstrukciója. 4. Életút-interjúk, esettanulmányok, fotók, térképek készítése a kitelepítések térségeiben és a kitelepítettek körében 5. Prezentációk, referátumok, kiállítások a témakörben | 1. Statistical analysis of the data gained in the survey Deportees and Their Families and also of the data of lists of the deportees available from other researches. Analyses of interviews. An edited collection of thematic papers on the bases of these analyses (draft). 2. A collection of basic theoretical categories and framework for describing the social structure of the researched population. 3. Fieldwork in the main bases of the deportations, basically on the southern and western border zone, and also on the places of the deportations: on the Hungarian plane. A social reconstruction of the regions affected by the deportation. 4. Interviews with deportees, case studies of deportations, photo and map documentations. 4. Papers, presentations, exhibitions

BC-Monitor: Towards a Routinely Accessible Circulating Tumor DNA-Based Tool for Real-Time Monitoring Breast Cancer Progression and Treatment Effectiveness

, László Tordai 4 , Rozália Tóth 4 , Zsuzsanna Kahán 4 and Lajos Haracska 5,

A genetikán is túl - Az epigenetika előretörése és orvosi vonatkozásai [Beyond genetics - The emerging role of epigenetics and its clinical aspects].

Analysis of genomic sequences has clearly shown that the genomic differences among species do not explain the diversity of life. The genetic code itself serves as only a part of the dynamic complexity that results in the temporal and spatial changes in cell phenotypes during development. It has been concluded that the phenotype of a cell and of the organism as a whole is more influenced by environmentally-induced changes in gene activity than had been previously thought. The emerging field of epigenetics focuses on molecular marks on chromatin; called the epigenome, which serve as transmitters between the genome and the environment. These changes not only persist through multiple cell division cycles, but may also endure for multiple generations. Irregular alterations of the epigenome; called epimutations, may have a decisive role in the etiology of human pathologies such as malignancies and other complex human diseases. Epigenetics can provide the missing link between genetics, disease and the environment. Therefore, this field may have an increasing impact on future drug design and serve as a basis for new therapeutic/preventative approaches. Orv. Hetil., 2012, 153, 214-221