Localization of callose in microspores and pollen grains in <Emphasis Type="Italic">Sium latifolium</Emphasis> L. plants in different water regimes

Results of studies of the topography and content of callose in the process of microsporogenesis as well as the formation of pollen grain in dry-valley and air-aquatic Sium latifolium L. plants grown under the conditions of different water regimes are presented. An increase in the content of callose in the microspore walls at the tetrad stage and in the pollen grains of dry-valley S. latifolium plants is discovered based on the intensity of fluorescence of the callose and a quantitative luminescence analysis. This result is obviously associated chiefly with the function of callose in maintaining moisture under conditions of water deficit.     

Development of polymorphic microsatellite markers in sesame (Sesamum indicum L.)

Fifty microsatellite sequences (SSRs) were isolated from an enriched library of sesame (Sesamum indicum L.) using a modified protocol. After screening, 10 polymorphic microsatellites were used to determine their usefulness in diversity analysis among 16 sesame accessions. The number of alleles ranged from three to six alleles per locus with an average of 4.6 alleles. The fragment size varied from 150 bp to 307 bp. Expected heterozygosites (H_E) and polymorphism information contents (PICs) ranged from 0.437 to 0.858 and 0.34 to 0.80, respectively, which indicates the highly informative nature of the microsatellites reported here. These microsatellite markers will be very useful in diversity analysis among a large germplasm collection of sesame present in our Korean gene bank and also in the establishment of its core collection.     

The effect of growth rate and culturing conditions on the stability of plasmid pCJ55 and on the level of expression of a large fragment of DNA-polymerase I, cloned in Escherichia coli

Plasmid pCJ55 with a cloned gene for the large fragment of Escherichia coli DNA polymerase I is stable in the population of a recombinant strain under the conditions of batch and continuous cultivation at different dilution rates in the presence of ampicillin. The level of Klenow fragment expression is determined by at least two factors: the stability of the recombinant strain and its specific growth rate. The maximal activity of the Klenow fragment was found after thermoinduction of the culture growing at a rate of mu = 0.6 h-1 in a synthetic medium with bactopeptone and glucose as a carbon source.     

Hot spots for nitrous oxide emissions found in different types of permafrost peatlands

Recent findings on large nitrous oxide (N₂O) emissions from permafrost peatlands have shown that tundra soils can support high N₂O release, which is on the contrary to what was thought previously. However, field data on this topic have been very limited, and the spatial and temporal extent of the phenomenon has not been known. To address this question, we studied N₂O dynamics in two types of subarctic permafrost peatlands, a peat plateau in Russia and three palsa mires in Finland, including also adjacent upland soils. The peatlands studied have surfaces that are uplifted by frost (palsas and peat plateaus) and partly unvegetated as a result of wind erosion and frost action. Unvegetated peat surfaces with high N₂O emissions were found from all the studied peatlands. Very high N₂O emissions were measured from peat circles at the Russian site (1.40±0.15 g N₂O m^?2 yr^?1). Elevated, sparsely vegetated peat mounds at the same site had significantly lower N₂O release. The N₂O emissions from bare palsa surfaces in Northern Finland were highly variable but reached high rates, similar to those measured from the peat circles. All the vegetated soils studied had negligible N₂O release. At the bare peat surfaces, the large N₂O emissions were supported by the absence of plant N uptake, the low C : N ratio of the peat, the relatively high gross N mineralization rate and favourable moisture content, together increasing availability of mineral N for N₂O production. We hypothesize that frost heave is crucial for high N₂O emissions, since it lifts the peat above the water table, increasing oxygen availability and making it vulnerable to the the physical processes that may remove the vegetation cover. In the future, permafrost thawing may change the distribution of wet and dry surfaces in permafrost peatlands, which will affect N₂O emissions.     

No regulatory role for adult predation in cyclic population dynamics of the autumnal moth,Epirrita autumnata

1. Multiannual population cycles of geometrid moths are thought to be driven by trophic‐level interactions involving a delayed density‐dependent component. Predation on adult moths has been a little‐studied mechanism of this phenomenon. 2. Using 29 daytime and 61 night‐time predation trials in the field, we exposed living autumnal moth (Epirrita autumnata Borkhausen, Lepidoptera: Geometridae) females to their natural predators during each autumn throughout the 10‐year population cycle. 3. In our northern study location (70°N), insectivorous passerines had already migrated, and harvestman Mitopus morio Fabricius (Opiliones: Phalangiidae) was found to be the main predator of the adult moths. The predation mortality occurred mainly at night and was positively correlated with the minimum temperature measured during the predation trial. 4. Despite high annual variability in the degree of adult predation, both direct and delayed density‐dependent effects were weak and indicate that predation on adult moths in the autumn does not have any regulatory role in cyclic population dynamics of the autumnal moth in northern Fennoscandia.     

Characterization of new microsatellite markers in mung bean,Vigna radiata (L.)

The present work reports the isolation and characterization of new polymorphic microsatellites in mung bean (Vigna radiata L.). Of 93 designed primer pairs, seven were found to amplify polymorphic microsatellite loci, which were then characterized using 34 mung bean accessions. The number of alleles ranged from two to five alleles per locus with an average of three alleles. Observed and expected heterozygosity values ranged from 0 to 0.088 and from 0.275 to 0.683, respectively. All seven loci showed significant deviations from Hardy–Weinberg equilibrium, whereas only one pairwise combination (GBssr‐MB77 and GBssr‐MB91) exhibited significant departure from linkage disequilibrium. These newly developed markers are currently being utilized for diversity assessment within the mung bean germplasm collection of the Korean Gene Bank.     

Chlorpromazine oligomer is a potentially active substance that inhibits human D-amino acid oxidase,product of a susceptibility gene for schizophrenia

D-Amino acid oxidase (DAO), a potential risk factor for schizophrenia, has been proposed to be involved in the decreased glutamatergic neurotransmission in schizophrenia. Here we show the inhibitory effect of an antipsychotic drug, chlorpromazine, on human DAO, which is consistent with previous reports using porcine DAO, although human DAO was inhibited to a lesser degree (K_i = 0.7 mM) than porcine DAO. Since chlorpromazine is known to induce phototoxic or photoallergic reactions and also to be transformed into various metabolites, we examined the effects of white light-irradiated chlorpromazine on the enzymatic activity. Analytical methods including high-resolution mass spectrometry revealed that irradiation triggered the oligomerization of chlorpromazine molecules. The oligomerized chlorpromazine showed a mixed type inhibition with inhibition constants of low micromolar range, indicative of enhanced inhibition. Taken together, these results suggest that oligomerized chlorpromazine could act as an active substance that might contribute to the therapeutic effects of this drug.     

Life cycle assessment tool for estimating net CO2 exchange of forest production

The study describes an integrated impact assessment tool for the net carbon dioxide (CO₂) exchange in forest production. The components of the net carbon exchange include the uptake of carbon into biomass, the decomposition of litter and humus, emissions from forest management operations and carbon released from the combustion of biomass and degradation of wood‐based products. The tool enables the allocation of the total carbon emissions to the timber and energy biomass and to the energy produced on the basis of biomass. In example computations, ecosystem model simulations were utilized as an input to the tool. We present results for traditional timber production (pulpwood and saw logs) and integrated timber and bioenergy production (logging residues, stumps and roots) for Norway spruce, in boreal conditions in Finland, with two climate scenarios over one rotation period. The results showed that the magnitude of management related emissions on net carbon exchange was smaller when compared with the total ecosystem fluxes; decomposition being the largest emission contributor. In addition, the effects of management and climate were higher on the decomposition of new humus compared with old humus. The results also showed that probable increased biomass growth, obtained under the changing climate (CC), could not compensate for decomposition and biomass combustion related carbon loss in southern Finland. In our examples, the emissions allocated for the energy from biomass in southern Finland were 172 and 188 kg CO₂ MW h^?1 in the current climate and in a CC, respectively, and 199 and 157 kg CO₂ MW h^?1 in northern Finland. This study concludes that the tool is suitable for estimating the net carbon exchange of forest production. The tool also enables the allocation of direct and indirect carbon emissions, related to forest production over its life cycle, in different environmental conditions and for alternative time periods and land uses. Simulations of forest management regimes together with the CC give new insights into ecologically sustainable forest bioenergy and timber production, as well as climate change mitigation options in boreal forests.