Deadwood volume in strictly protected,natural, and primeval forests in Poland

Standing and downed deadwood at different stages of decay provides a crucial habitat for a wide range of organisms. It is particularly abundant in unmanaged forests, such as strictly protected areas of national parks and nature reserves. The present work used the available data for such sites in Poland, analyzing a total of 113 studies concerning 79 sites to determine the causes contributing to variation in deadwood volume based on the duration of conservation, changes in deadwood volume over time (for those sites which were examined multiple times), elevation above sea level, forest type, stage of forest development, input of dead trees from the years preceding deadwood measurements, live tree volume, and the proportion of downed to standing deadwood). Depending on species composition and site altitude, most tree stands fell into one of four categories: subalpine spruce forests, montane beech-fir forests, low altitude beech-fir forests, or oak-hornbeam and riparian forests. The mean deadwood volume for all forest types amounted to 172.0 m³/ha. The mean volume of deadwood in montane beech-fir forests (223.9 m³/ha) was statistically significantly greater than in the other three forest types, for which it ranged from 103.5 to 142.5 m³/ha. A direct effect of the duration of conservation on deadwood volume was not identified. Nevertheless, analysis of repeated measurements on the same sample plots at 10-year intervals showed a consistent rise in mean deadwood volume. A linear regression model for all the analyzed factors reported from montane beech-fir forests and subalpine spruce forests showed that in addition to site altitude, another statistically significant variable was the input of dead trees (R²?=?63.54%).     

A simple and efficient CRISPR/Cas9 platform for induction of single and multiple,heritable mutations in barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)

Background

Genome editing of monocot plants can be accomplished by using the components of the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat/CRISPR associated Cas9) technology specifically optimized for these types of plants. Here, we present the development of RNA-guided Cas9 system for simplex and multiplex genome editing in barley.

Results

We developed a set of customizable RNA-guided Cas9 binary vectors and sgRNA modules for simplex and multiplex editing in barley. To facilitate the design of RNA-guided Cas9 constructs, the pBract derived binary vectors were adapted to Gateway cloning and only one restriction enzyme was required for construction of the sgRNA. We designed a synthetic, codon optimized Cas9 gene containing the N terminal SV40 nuclear localization signal and the UBQ10 Arabidopsis 1st intron. Two different sgRNAs were constructed for simplex editing and one polycistronic tRNA-gRNA construct (PTG) for multiplex editing using an endogenous tRNA processing system. The RNA-guided Cas9 constructs were validated in transgenic barley plants produced by Agrobacterium-mediated transformation. The highest mutation rate was observed in simplex editing of the cytokinin oxidase/dehydrogenase HvCKX1 gene, where mutations at the hvckx1 locus were detected in 88% of the screened T₀ plants. We also proved the efficacy of the PTG construct in the multiplex editing of two CKX genes by obtaining 9 plants (21% of all edited plants) with mutations induced in both HvCKX1 and HvCKX3. Analysis of the T₁ lines revealed that mutations in the HvCKX1 gene were transmitted to the next generation of plants. Among 220 screened T₁ plants we identified 85 heterozygous and 28 homozygous mutants, most of them bearing frameshift mutations in the HvCKX1 gene. We also observed independent segregation of mutations and the Cas9-sgRNA T-DNA insert in several T₁ plants. Moreover, the knockout mutations of the Nud gene generated phenotype mutants with naked grains, and the phenotypic changes were identifiable in T₀ plants.

Conclusions

We demonstrated the effectiveness of an optimized RNA-guided Cas9 system that can be used for generating homozygous knockout mutants in the progeny of transgenic barely plants. This is also the first report of successful multiplex editing in barley using a tRNA processing system.

     

The involvement of the anterior cingulate cortex in remote contextual fear memory

Although the molecular, cellular, and systems mechanisms required for initial memory processing have been intensively investigated, those underlying permanent memory storage remain elusive. We present neuroanatomical, pharmacological, and genetic results demonstrating that the anterior cingulate cortex plays a critical role in remote memory for contextual fear conditioning. Imaging of activity-dependent genes shows that the anterior cingulate is activated by remote memory and that this activation is impaired by a null alpha-CaMKII mutation that blocks remote memory. Accordingly, reversible inactivation of this structure in normal mice disrupts remote memory without affecting recent memory.     

Diversity of ectomycorrhizal fungus assemblages on nursery grown European beech seedlings

? Context

An important feature of forest nursery management is the production of first-rate planting stock, which is closely connected with an adequate development of ectomycorrhizas on seedling roots.

? Aims

The aim of this study was to provide a detailed assessment of the ectomycorrhizal (ECM) fungal diversity of European beech grown in bare-root forest nursery conditions.

? Methods

Morphological and molecular analyzes were used to identify ECM fungi, quantify fungal richness, and record differences in the relative abundance of individual taxa.

? Results

Twenty-seven different mycorrhizal fungal taxa were found in four tested nurseries. Of these 27, only 6 were present in more than one nursery. Taxa richness in individual nurseries ranged from 6 to 13, indicating that ECM colonization potential is nursery-dependent. The most frequent taxa were: Tuber sp. 1, Cadophora sp., Cenococcum geophilum agg., Hebeloma sacchariolens, and Laccaria tortilis. According to the analysis of similarity, ECM fungal communities were significantly different between nurseries (R?=?0.7741; p?<?0.0001).

? Conclusion

Beech seedlings grown in bare-root nurseries are colonized by a highly diverse suite of ECM fungi; thus, artificial inoculation of seedlings is generally not necessary in nursery practice.     

Response of a Juvenile Cyprinid,Lake Minnow <Emphasis Type="Italic">Eupallasella perenurus</Emphasis> (Pallas), to Different Diets

Three commercial starters (Carp Starter, Uni Starter and Perla Plus) and one non-commercial, with frozen Chironomidae larvae as a reference diet, were evaluated for the intensive rearing of juvenile lake minnow Eupallasella perenurus, a cyprinid fish that is critically endangered in Poland. The growth, condition, survival, body deformities, and chemical body composition were studied. The 90-day laboratory experiment was performed at 22 °C with fish that were initially 24.6 mm (mean total lenth (TL)) and 0.11 g (mean body weight (BW)). Satisfactory fish growth was attained with all of the diets; however, the largest (p ≤ 0.05) final size (48.5 mm TL, 1.55 g BW) and the lowest condition coefficient (K = 1.34) were noted in fish fed the non-commercial starter. The final survival rates were very high (97.5–100%). Skeletal deformities (in 74 to 92% fish) were recorded exclusively in fish fed commercial starters. All commercial starters resulted in considerably higher lipid content and lower ash content than did the non-commercial starter and the reference diet. This suggests that both these factors might be responsible for body deformities. The present results proved that only the non-commercial starter is suitable for juvenile E. perenurus rearing under controlled condition, and that none of the commercial starters can be recommended.     

The effects of different types of management,functions, and characteristics of stands in Polish forests on the amount of coarse woody debris

In the modern forestry paradigm, many factors influence the amount of coarse woody debris (CWD). The present paper analyzes the effects of both local (national) programs (special functions of forests) and European programs (Natura 2000 sites), as well as the individual characteristics of forest stands. The study was conducted on 2,752 sampling plots distributed over an area of about 17,500 ha and located in lowland stands having a species composition typical of large areas in central Europe. Natura 2000 areas contained significantly more CWD (8.4 m³/ha) than areas not covered by the program (4.8 m³/ha). However, this is due to the fact that Natura 2000 sites involve well-preserved forest areas, such as nature reserves (26.6 m³/ha). In the managed forests that have been covered by the Natura 2000 program over the past several years, the volume of CWD has not increased. Forests with ecological and social functions differed slightly in the amount of CWD. More CWD occurred in protected animal areas (8.7 m³/ha) than in stands damaged by industry (3.9 m³/ha). Intermediate CWD levels were found in water-protection forests and in forests located around cities and military facilities. In managed forests, the lowest CWD volume was observed in middle-aged stands. The species composition of the stand had little effect on the volume of CWD. Only stands with a predominance of ash and alder had higher CWD levels (13.5 m³/ha). More CWD was found in stands whose species composition did not represent the potential site quality (6.4 m³/ha) than in habitats with the optimum species composition (3.8 m³/ha). CWD volume should be systematically increased taking into consideration local natural conditions. Such efforts should be focused on particularly valuable regions, and especially on Natura 2000 sites, where the threshold values reported from other European forests should be reached. Leaving some trees to die naturally and retaining reasonable amounts of such trees ought to be incorporated into CWD management practice in Poland.     

Comparative scanning electron microscope analysis of the enamel of permanent human,bovine and porcine teeth

BackgroundBovine and porcine teeth are often used in in vitro experiments as substitutes of human teeth.ObjectivesThe aim of the present study was to perform a comparative analysis of enamel morphology of permanent human, bovine and porcine teeth under the scanning electron microscope.MethodsAs many as 10 human, 10 bovine, and 10 porcine teeth were studied. All the teeth were sectioned and the halves were randomly divided into 2 groups according to the examined tissue (vestibular enamel at the mid-height of the dental crown and in the cervical area). Human and bovine enamel was etched for 15 sec and porcine enamel for 30 sec. The scanning electron microscope analysis was performed. The length and width of enamel prisms were determined with the “Met-Ilo” 1.1 computer program.ResultsAll enamel samples revealed the same etching pattern—Silverstone''s type 2. Bovine enamel showed a similar porosity and the amount of interprismatic enamel compared to human enamel while the amount and width of interprismatic enamel bands in porcine enamel were evidently greater. The shape of the porcine prisms was visually similar to human prisms, although dimensions were significantly different. However, bovine prisms differed in form and appeared to be distinctly elongated.ConclusionsReported findings indicate that the results of experimental studies carried out on bovine and porcine enamel should not be compared with the results obtained on human enamel.     

Selected Nutrients and Iron in Interstitial Waters of the Estuary of Southern Baltic (Gulf of Gdañsk and the Pomeranian Bay) in Relation to Redox Potential

The following parameters were determined in the interstitial waters of the Gulf of Gdańsk and the Pomeranian Bay: nutrients (ammonia and phosphates), sulphates, total iron and iron(II) concentrations. Redox potential (Eh), pH, humidity and organic matter content measured as a loss on ignition were determined in bottom sediments from these regions. Interstitial waters of both regions were found to have reducing character (Eh < 250 mV). Reduction processes were more advanced in the Gulf of Gdańsk, rich in organic matter, as evidenced by lower values of the redox potential, lower Fe(III)/Fe_tot ratio, and incidents of sulphates exhaustion.     

Profile Distributions of Lead,Zinc, and Copper in Dystric Cambisols Developed from Granite and Gneiss of the Sudetes Mountains,Poland

Total contents of Pb, Zn and Cu were examined in twenty-five soilprofiles of forested Dystric Cambisols developed from granite andgneiss in the area of the Sudetes Mountains (SW Poland). Sequential extraction of heavy metals was also carried out to study relations between metal content and soil compounds. Profile distribution differed among the metals examined: Pb concentrations decreased gradually from surface with depth, whereas those of Zn increased with depth of soil profile, obtaining their maximum in the bedrock horizon. Cu was found to accumulate in topsoil and decrease with depth, but showed secondary increase of the concentration in bedrock. Organic matter was found to be a crucial factor of Pb binding and distribution, while iron oxides played the most important rolein Zn binding. Both organic matter and oxides were important factors of Cu distribution. The results of sequential extractionshow that all studied elements are mobile under strong acidicconditions in investigated Cambisols. Thus, total contents of Zn and Cu in bedrock cannot be used as geochemical background or as reference levels for assessing the contamination of soilsurface with these metals.