The Balkan chamois,an archipelago or a peninsula? Insights from nuclear and mitochondrial DNA

The Balkan chamois (Rupicapra rupicapra balcanica) is widespread on the Balkan Peninsula, along mountain massifs from Croatia in the north to Greece in the south and Bulgaria in the east. Knowledge on the genetic structure of Balkan chamois populations is limited and restricted to local studies. Therefore, the main objective of this study was to use nuclear (16 microsatellites) and mitochondrial (partial 376 base pairs control region) markers to investigate the genetic structure of this chamois subspecies throughout its distribution range and to obtain information on the degree of connectivity of the different (sub)populations. We extracted DNA from bone, dried skin and muscle tissue and successfully genotyped 92 individuals of Balkan chamois and sequenced the partial control region in 44 individuals. The Bayesian analysis suggested 3 genetic clusters and assigned individuals from Serbia and Bulgaria to two separate clusters, while individuals from the other countries belonged to the same cluster. Thirty new haplotypes were obtained from partial mitochondrial DNA sequences, with private haplotypes in all analyzed populations and only two haplotypes shared among populations, indicating the possibility of past translocations. The subspecies genetic composition presented here provides the necessary starting point to assess the conservation status of the Balkan chamois and allows the development of conservation strategies necessary for its sustainable management and conservation.

     

Interactive effects of pests increase seed yield

Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides.     

Estrone derived steroidal diepoxide: Biologically active compound and precursor of a stable steroidal A,B-spiro system

A simple approach to a stable steroidal estrone derived A,B-spiro system is reported. Treatment of estrone derived A-ring diepoxyalcohol with the Ac₂O–TMSOTf system at the ambient temperature led to acetylation, while at the reflux temperature the acid-catalysed rearrangement took place affording the spiro-compound. Results of extensive in vitro and in vivo anticancer tests on the diepoxide, as well as preliminary data on the antiproliferative activity of the spiro-product against three cancer cell lines, are also presented.     

Genetic characterization of grey wolves (<Emphasis Type="Italic">Canis lupus</Emphasis> L. <Emphasis Type="Italic">1758</Emphasis>) from Bosnia and Herzegovina: implications for conservation

The grey wolves of Bosnia and Herzegovina form a subpopulation of the Dinaric-Balkan wolf population and represent one of Europe’s least studied wolf populations. Since the Dinaric-Balkan population is a valuable source of genetic diversity for neighboring populations, comprehensive assessments are warranted. We aimed to determine the genetic variability and structure of the grey wolf population from Bosnia and Herzegovina, as well as estimate levels of gene flow and inbreeding and evaluate genetic signals of a bottleneck. To do this, we analyzed the variability of eighteen microsatellite loci. We found moderately high genetic heterozygosity for wolves from Bosnia and Herzegovina, as described for other Dinaric-Balkan wolf populations. We reveal weak genetic structuring with two genetic clusters identified. Wolves from the eastern part of the region formed a relatively distinct cluster, whereas individuals in the second cluster overlapped quite considerably with admixed individuals. Despite the signal of genetic structure being weak, clustering of individuals from the eastern part of the country extended through all analyses. Thus, this cluster could be considered a separate management unit, perhaps requiring specific conservation attention.     

Selenium nanoparticles in poultry feed modify gut microbiota and increase abundance of Faecalibacterium prausnitzii

Applied Microbiology and Biotechnology - The poultry industry aims to improve productivity while maintaining the health and welfare of flocks. Pathogen control has been achieved through...     

Community structure of branchiopods (Anostraca,Notostraca and Conchostraca) in the Banat province in Yugoslavia

A survey of large branchiopods in the Banat provincein Yugoslavia revealed a particularly diverse fauna in the vicinity of the village Melenci, 100 km north of Belgrade. The temporary ponds here include 10 species of branchiopods, 5 anostracans, 2 notostracans and 3conchostracans (all belonging to the Spinicaudata group). This diversity represents 53% of the species known in Yugoslavia. Community structure, spatial distribution and seasonal dynamics of the species were analyzed over the period 1991–1995. More than one species was found in about 67% of ponds. The maximum number of coexisting species was 7.Anostracans were the most common as a group, while the notostracan Triops cancriformis and the conchostracan Leptestheria saetosa were the most frequent species. A high frequency of coexistence was established. Regarding community structure, two significantly different periods during the season were distinguished: the first, from the end of February to mid-April, and the second, from mid-April to the end of July. This extensive pool longevity may underlie the high diversity in this region. This revised version was published online in August 2006 with corrections to the Cover Date.     

Photosynthetic light-response curves and photoinhibition of the deep-water laminaria abyssalis and the intertidal laminaria digitata (phaeophyceae)

Photosynthetic light‐response curves of the deep‐water Laminaria abyssalis Oliveira and of the intertidal L. digitata Lamoroux were determined and related to photoinhibition phenomena as monitored by oxygen evolution and photosystem II efficiency (F_V/F_M). L. abyssalis has half the pigment content, number of cells and plastids, and photosynthetic capacity per unit area compared with L. digitata. L. abyssalis showed a higher in vivo Chl a absorption coefficient and higher photosynthetic efficiency on a Chl a basis, although the two algae showed somewhat similar light‐response curves on a Chl a basis. Both species showed similar Chl a/Chl c and Chl a/fucoxanthin ratios, and similar dark respiration rates and light compensation points. In addition, they also showed similar convexities in their light‐response curves and no differences in their light saturation of F_V/F_M. Room temperature chlorophyll fluorescence induction measurements of fronds incubated in 3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU) suggest that both species may have a similar PSII absorption cross section. Thus, L. abyssalis appears to optimize its light absorption at very low light intensities, not by increasing the pigment content, but by absorbing light more efficiently. However, L. abyssalis was more sensitive to photoinhibition than L. digitata and showed no recovery of F_V/F_M and O₂ evolution after a photoinhibitory treatment, even with a subsequent exposure to 24 h of dim light. L. digitata, on the other hand, recovered its photosynthetic capacity within 6 h under dim light. These results suggest that photosynthetic light‐induction curves based on Chl a are not a good indicator of either the photosynthetic capacity or the sensitivity to photoinhibition when macroalgae of different species are being compared. Based on their light‐response and photoinhibition characteristics, we suggest that L. abyssalis, a deep‐water oceanic macroalgae, is an atypical shade alga whereas L. digitata has the properties of a sun alga.     

Synergy between <Emphasis Type="Italic">Salvia officinalis</Emphasis> L. and some preservatives

The aim of the present study is to investigate the antibacterial activity of Salvia officinalis L. aqueous extracts and its synergistic action with preservatives sodium nitrite, sodium benzoate and potassium sorbate in vitro against selected food spoiling bacteria. Synergy was assessed by the checkerboard assay method and quantitatively represented by the FIC index. Synergistic action was established for aqueous extract/ sodium benzoate, aqueous extract/ potassium sorbate, aqueous extract/ sodium nitrite combinations. Synergy was detected in relation to: Agrobacterium tumefaciens, Bacillus subtilis and Proteus sp. Synergy was established at plant extract and preservative concentrations corresponding up to 1/8 MIC values.     

A SMALLER AND IMPAIRED XANTHOPHYLL CYCLE MAKES THE DEEP SEA MACROALGAE LAMINARIA ABYSSALIS (PHAEOPHYCEAE) HIGHLY SENSITIVE TO DAYLIGHT WHEN COMPARED WITH SHALLOW WATER LAMINARIA DIGITATA1

Pigment composition, fluorescence parameters, and oxygen evolution of the deep water Laminaria abyssalis Oliveira and of the shallow water L. digitata Lamoroux were determined in response to high irradiances. This was performed in the presence and absence of an inhibitor of violaxanthin de‐epoxidase (dithiothreitol) or an inhibitor of the chloroplast‐encoded protein synthesis (chloramphenicol). Photochemical quenching in L. digitata was almost 3‐fold that seen in L. abyssalis, whereas both nonphotochemical quenching and PSII photochemical yield were doubled. Laminaria digitata possessed a xanthophyll‐cycle pool nearly double that of L. abyssalis. After photoinhibitory treatment, L. digitata displayed substantial violaxanthin de‐epoxidation, whereas in L. abyssalis de‐epoxidation only took place in limited amounts. Both species were able to fully recover their epoxidation status after transfer back to dim light. Overnight incubation with dithiothreitol fully blocked de‐epoxidation in both species, and both displayed similar fluorescence properties. Chloramphenicol caused no change in their fluorescence parameters. With high light treatment, L. abyssalis was completely and irreversibly inhibited both in the presence and absence of inhibitors, whereas L. digitata showed 60% inhibition of its photosynthetic activity and full recovery in the absence of inhibitors. In the presence of dithiothreitol, L. digitata did not recover to the preillumination conditions and chloramphenicol delayed the recovery of the oxygen evolution activity. We suggest that the xanthophyll cycle is the main mechanism of photoprotection of these Laminaria species and that the higher susceptibility of L. abyssalis to photoinhibition may be due to its limited de‐epoxidation capacity and reduced xanthophyll‐cycle pool size.