Past,present and future suitable areas for the relict tree Pterocarya fraxinifolia (Juglandaceae): Integrating fossil records,niche modeling,and phylogeography for conservation

European Journal of Forest Research - Pterocarya fraxinifolia, native to the southern Caucasus and adjacent areas, has been widely introduced in Europe. In this study, we investigate the following:...     

Effect of Alpha-Linolenic Acid Sources in Diets for Nile Tilapia on Fatty Acid Composition of Fish Fillet Using Principal Component Analysis

This study evaluated the effect of feed supplementation with chia and canola oils as a substitute for soybean oil on the composition of Nile tilapia muscle tissue using chemometrics. Diets were supplemented with 2.1% of each oil and were provided to fish for 15 and 30 days. Compared to soybean oil, supplementation with canola and chia oils significantly increased (P < 0.05) the contents of eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5 n-3), and docosahexaenoic acid (DHA, 22:6 n-3) in Nile tilapia fillet. At 30 days, DHA content increased 97% in Nile tilapia fed chia oil and 91% in treatment with canola oil. The highest EPA content correlated to treatment with chia oil (7.33 mg 100 g^?1). The long-chain polyunsaturated fatty acids (LC-PUFAs) precursors, linoleic acid and α-linolenic acid, were observed to increase according to treatment type and feed supplementation duration. The principal component analysis resulted in a two-principal-component model that described 92.07% of the total data variance. Also, it highlighted that the replacement of soybean oil with canola and chia oils in Nile tilapia diets contributed to increasing the n-3 LC-PUFA concentration in Nile tilapia fillets, improving its nutritional value.     

Changes in the physical and the sensorial properties of wheat bread caused by interruption and slowing of the fermentation of yeast-based leaven

Here we propose an original study on the effect of an interruption and slowing of the fermentation of yeast-based leaven on the physical properties of bread.     

Hypnea musciformis: alternative or complement to the production of Kappaphycus alvarezii introduced in tropical countries?

Hypnea musciformis that are harvested from natural beds and introduced Kappaphycus alvarezii are the two main sources of raw material for the production of carrageenan in Brazil. The daily growth rate (DGR) and carrageenan yield (CY) of both species were evaluated in vitro and in the sea to assess the feasibility of cultivating H. musciformis as a complement or as an alternative to the production of K. alvarezii. The DGR of H. musciformis (10.8 ± 0.6% day^?1) was higher than the DGR of K. alvarezii (5.6 ± 0.3% day^?1) in vitro, and the CY extracted using NaOH (62.3 ± 0.15%) was better than using KOH (32.0 ± 0.3%). In eutrophic medium, the DGR of H. musciformis (9.4 ± 2.1% day^?1) was higher than that of K. alvarezii (5.0 ± 1.2% day^?1). However, in this condition, the CY was similar for both species (50.2 ± 3.5%), and both species were effective in removing nutrients (30% NH₄⁺, 18% NO^2? and 2.4% ). H. musciformis did not survive when cultivated in the sea, neither in monospecific nor in multispecific cultivation. Moreover, K. alvarezii grew better in monospecific cultivation throughout the year (from 1.73 to 5.15% day^?1) except during the wet period and the CY was high in both cultivation types (33.7–50.8%). We conclude that the cultivation of H. musciformis is not an alternative to K. alvarezii on the Brazilian southeastern coast. However, the results in vitro suggested its use as a complementary source of carrageenan or as a biological filter.     

Influence of seminal plasma during different stages of bovine sperm cryopreservation

This study aimed to evaluate the effect of seminal plasma on bovine sperm cryopreservation and to assess the integrity of plasma and acrosomal membranes, mitochondrial potential, remodelling of F-actin cytoskeleton and sperm chromatin fragmentation during the cooling, equilibrium and freezing/thawing stages. Six ejaculates collected from seven Nelore bulls (n = 42) were used in this study. Each ejaculate was divided into two aliquots (with seminal plasma = SP group; without seminal plasma = NSP group) and packed to a final concentration of 50 × 10⁶ sperm per straw. Statistical analyses were performed using SAS software (version 9.3), and p ≤ .05 was considered significant. A time effect was observed for all sperm characteristics (p < .05), except for chromatin fragmentation (p > .05). The presence of seminal plasma better preserved the acrosomal integrity (SP = 75.2% and NSP = 71.7%; p < .05) and also provided lower F-actin remodelling during cryopreservation process (SP = 29.9% and NSP = 32.4%; p < .05). Regarding to the cryopreservation stages, it was observed that cooling step induced higher remodelling of F-actin than the equilibrium and freezing/thawing stages (56.3%, 32.2% and 23.9%, respectively; p < .05). The equilibrium step had minor influence on overall sperm characteristics while the freezing/thawing stage was responsible for the highest percentage of damage in plasma membrane (−65.2%), acrosomal membrane (−34.0%) and mitochondrial potential (−48.1%). On the other hand, none of the cryopreservation stages affected chromatin integrity. It was concluded that the presence of seminal plasma provides increased acrosomal integrity and reduced remodelling of F-actin cytoskeleton. Higher F-actin remodelling is observed after the cooling step while the freezing/thawing step is most damaging to sperm membranes and mitochondrial potential during bovine sperm cryopreservation.     

Reaction of three potato cultivars to potato virus S and alteration of miRNAs and mRNA targets in the resistant genotypes

Reactions of three Polish potato cultivars to potato virus S (PVS) were investigated at 22°C. Cultivars Tajfun and Tonacja exhibited partial resistance with systemic infection detected in some inoculated plants; cultivar Bryza was susceptible to PVS with systemic infection detected in all inoculated plants. The virus was not detectable by ELISA at 23 days postinoculation (dpi) but was detected after 40 dpi. Infection rate and viral accumulation were significantly lower in Tonacja and Tajfun than in Bryza, but no statistically significant difference between Tajfun and Tonacja was detected. Both susceptible and resistant genotypes displayed various, either common or cultivar-specific, symptoms. Delayed systemic infection at 56 dpi was observed in some cases in Tonacja and Tajfun. Resistance-related alteration of a set of miRNAs and mRNA targets in the tested cultivars in response to PVS at 22°C exhibited inter- and intracultivar variability. The majority of tested genes were altered only in the partially resistant Tajfun and Tonacja but not in the susceptible Bryza. Enhanced expression of AGO1-2, DCL1, stu-miR482 and its target Gpa2 was observed in Tonacja and plants of Tajfun in which PVS was detected, with the highest induction of Gpa2 in Tajfun (30.2-fold). However, their expression remained unchanged or decreased in plants of Tajfun in which PVS was undetected. Increased expression of stu-miR168a and stu-miR172e was observed in Tonacja and the PVS-undetected plants of Tajfun, respectively, but not in the PVS-detected plants of Tajfun. This is the first report on cultivar-specific alteration of miRNA in a potato–PVS resistance interaction.     

Adaptation of wheat rusts to the wheat cultivars in former Czechoslovakia

Summary In former Czechoslovakia virulence of rusts attacking wheat was studied since the sixties. Since the same time genes for resistance in the registered cultivars were identified. The role of Berberis and Thalictrum as alternate hosts for stem rust and leaf rust, respectively, was investigated as well. Determined changes of virulence in rust populations could only partially be ascribed to changes of resistance genes in the grown cultivars. Unnecessary genes for virulence had no negative effect on the fitness of the pathogen. All tested samples of aeciospores from barberries attacked rye, not wheat. None of Thalictrum species occurring in the Czech and Slovak Republics was found to host wheat leaf rust. However, the sexual stage of wheat stem rust and wheat leaf rust could be induced on Berberis vulgaris and Thalictrum speciosissimum, respectively. General epidemiological conclusions are drawn from the results and experience of the last 35 years.     

The effect of supplementing sheep with rapeseed and linseed oils on the activity of pancreatic digestive enzymes

The aim of this study was to compare the effect of rapeseed and linseed oils added to the diet on pancreatic enzyme activities in sheep. The experiment was conducted on six adult sheep with a catheter introduced into the common bile–pancreatic duct and a T‐cannula into the duodenum. The animals were divided into three groups, two sheep in each. A twice‐replicated 3 × 3 Latin square was used in the experimental design. The sheep were fed meadow hay and the concentrate alone or the same ration supplemented with rapeseed or linseed oils at a dose of 5% of the basal diet. After adaptation period, a mixture of pancreatic and bile juice was collected for three consecutive days. The secretion of bile–pancreatic juice showed an increasing trend in sheep fed rapeseed and linseed oils (69.5 and 68.5 ml/hr respectively) in comparison with control ones (59.8 ml/hr). Lipase and trypsin activities were significantly increased when sheep were fed diets with rapeseed or linseed oils (175 and 21.6 or 179 and 23.2 U/L respectively) in comparison with those fed control diet (128 and 13.1 U/L respectively). It was concluded that oil as a dietary supplement can mainly modify the secretion of bile–pancreatic juice and enzymatic activity of the pancreas and also might affect animal production.     

Large volume cold on-column injection for gas chromatography-negative chemical ionization-mass spectrometry analysis of selected pesticides in air samples

A new gas chromatographic method is described for the analysis of fungicides captan, captafol, and folpet from organic extracts of air samples using large volume injection (LVI) via a cold on-column (COC) inlet coupled with gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS). Although standard split/splitless injection due to high injection port temperatures (>225 degrees C) have been shown to degrade these thermally labile fungicides, COC injection minimizes degradation. Insecticides such as chlorpyrifos and diazinon were also examined to show added selectivity. By using a solvent vapor exit with the COC inlet, injection volumes of 10-100 microL can be made to lower detection levels. GC-NCI-MS was compared to GC-electron impact ionization-mass spectrometry for each pesticide using LVI-COC injections and was found to be 2-80 times more sensitive, depending on the pesticide. Method detection limit (MDL) values with 100 microL injections were 2.5 microg L-1 for captan, folpet, and diazinon, 5.0 microg L-1 captafol, and 1.0 microg L-1 for chlorpyrifos, with the normal working range examined for sample analysis from MDL to 100 microg L-1. Detection of all pesticides except captafol, used only in the United States but not Canada, was demonstrated from air samples taken from Abbotsford, British Columbia, Canada.