Fatty acid content,health and risk indices,physicochemical composition,and somatic cell counts of milk from organic and conventional farming systems in tropical south-eastern Mexico

Organic agriculture and livestock farming is claimed to promote animal welfare and can offer animal products with better hygienic-sanitary quality, based on principles of health, ecology, fairness, and care. However, no clear advantages of organic milk (OM) versus conventional milk (CM) from tropical conditions are available. The aims of the study were to determine fatty acid profile, health-promoting (HPI) and thrombogenic (TI) indices, physicochemical composition, and somatic cell counts (SCC) of OM and CM in tropical south-eastern Mexico. Female cross-breed cows (400–600 kg) were employed. CM had larger values of saturated fatty acids (SFA) and polyunsaturated fatty acid (PUFA) (63.6 %; 4.57 %) than OM (61.48 %; 4.22 %), while OM resulted in a larger value of monounsaturated fatty acid (MUFA) (34.3 %) than CM (31.7 %). HPI and TI showed that OM was more favorable than CM. Milk production and physicochemical composition (PC) as well as density had no significant difference, while SCC was significantly lower in OM than in CM on a monthly basis. These results showed that OM promotes a healthful and balanced diet, and is already produced by sustainable ecologic technologies employing traditional agrosilvopastoral management, which is more environmentally friendly and promotes ecological resilience.     

Different earthworm ecological groups interactively impact seedling establishment

There is increasing evidence that direct interactions between earthworms and seeds impact the assembly of plant communities. However, effects of earthworms of different ecological groups and their interactions on plant germination and establishment are little known. We set up a full-factorial greenhouse experiment in order to explore impacts of different ecological groups of earthworms (epigeic, endogeic and anecic) on the establishment of seedlings. The three ecological groups of earthworms affected seedling establishment in an interactive way with the effects varying in time. While anecic earthworms detrimentally affected the number of established seedlings, impacts of epigeic and endogeic species depended on the presence of earthworms belonging to other ecological groups. Impacts of anecic earthworms were more significant and consistent than those of epigeic and endogeic ones pointing to the dominance of the effect of anecic earthworms for seedling establishment. The initial positive effect of the combined presence of epigeic and endogeic earthworms compared to treatments with only endogeic and only anecic earthworms was likely due to the acceleration of seed germination and elevated nutrient availability for seedlings in earthworm casts. By contrast, reduced numbers of seedlings in presence of both epigeic and endogeic earthworms compared to the control treatment might have been due to seedling predation after the litter layer had disappeared. The results extend current knowledge on interactions between earthworms and seeds by showing that, in addition to anecic species, also epigeic and endogeic species influence seedling establishment with their effect depending on the presence of anecic species. Moreover, the results indicate that impacts of earthworms vary with the developmental stage of seedlings highlighting the importance of interactions between earthworms and seeds.     

In Vitro Studies on Atrazine Effects on Human Intestinal Cells

Considering the importance of the oral route for human exposure to atrazine, we have investigated the possible effect of this herbicide on the human intestinal cells and the integrity of the epithelial barrier, using Caco-2 cells as the intestinal model in vitro. We evaluated possibile cytotoxic and genotoxic effects of atrazine in concentrations ranging from 1 to 250 μM on the Caco-2 cells at different stages of growth after short- and long-term exposure. Results from the tetrazolium blue (MTT) test and the Trypan blue exclusion assay showed that atrazine cytotoxicity was dose- and time-dependent. Obtained data indicated that atrazine at high concentrations (50 and 250 μM) was able to induce effects on Caco-2 proliferation and viability. Moreover, it was found that the long-term exposure to atrazine at the non-cytotoxic dose caused inhibition of the intestinal cell maturation and decreased the transepithelial electrical resistance, the indicator of the epithelial barrier integrity. Studies on the atrazine genotoxicity determined using the single cell microelectrophoresis assay indicated that atrazine did not induce DNA damages in the Caco-2 cells at concentrations of up to 50 μM, whereas enhancement in the DNA damage was observed at 250 μM. Altogether, our results indicate that atrazine at expected human oral exposure concentrations is not able to induce effects on the Caco-2 cell proliferation and viability, but may suppress the intestinal cell differentiation and reduce the cell monolayer integrity. We suggest that chronic exposure on low levels of atrazine may lead to alteration in the expression of the morphological and functional features of the Caco-2 cells related to the transport and barrier function of small intestinal enterocytes. In consequence, this may lead to alterations in the intestinal absorption process.     

Allium discoloration: the color-forming potential of individual thiosulfinates and amino acids: structural requirements for the color-developing precursors

Structural requirements for compounds involved in Allium discoloration have been investigated in detail. The abilities of all 20 protein amino acids and six naturally occurring 1-propenyl-containing thiosulfinates to form the pigments have been studied. Furthermore, several analogues of these thiosulfinates were prepared by synthesis, and their color-forming abilities were evaluated, together with those of various amino compounds. It has been found that an unsubstituted primary amino group and a free carboxyl group are essential structural features required for amino compounds to be able to generate the pigments. Out of the thiosulfinate analogues tested, only those containing at least a three-carbon chain with the beta-carbon bearing a hydrogen atom yielded the pigments after reacting with glycine. Thiosulfonates, sulfoxides, sulfides, and disulfides did not form any colored products when mixed with glycine. The pH optimum for pigment formation has been found to be between 5.0 and 6.0 for all thiosulfinates tested.     

The alarmin interleukin-33 drives protective antiviral CD8⁺ T cell responses

Pathogen-associated molecular patterns decisively influence antiviral immune responses, whereas the contribution of endogenous signals of tissue damage, also known as damage-associated molecular patterns or alarmins, remains ill defined. We show that interleukin-33 (IL-33), an alarmin released from necrotic cells, is necessary for potent CD8(+) T cell (CTL) responses to replicating, prototypic RNA and DNA viruses in mice. IL-33 signaled through its receptor on activated CTLs, enhanced clonal expansion in a CTL-intrinsic fashion, determined plurifunctional effector cell differentiation, and was necessary for virus control. Moreover, recombinant IL-33 augmented vaccine-induced CTL responses. Radio-resistant cells of the splenic T cell zone produced IL-33, and efficient CTL responses required IL-33 from radio-resistant cells but not from hematopoietic cells. Thus, alarmin release by radio-resistant cells orchestrates protective antiviral CTL responses.     

波兰的牧草育种与种子生产

对波兰近年来的牧草育种和牧草种子生产情况以及主要种子公司的研发状况进行了简述,以期为我国的牧草育种及种子生产提供借鉴。     

Net changes of main ions in the soil profile of irrigated field plots in central Spain

Implementation of improved irrigation schedules in some semiarid zones improve water efficiency and can be recommended where occasional periods of heavy rainfall may remove some of the accumulated salts. We hypothesized, however, that the leaching pattern of the main ions may differ regarding their potential contribution to the total salt discharge. The experiment was conducted near Madrid in Spain on a typical Xerofluvent soil with sandy-loam texture in the first 0.5 m. For 4 years, a traditional crop rotation of corn–wheat–corn–oat (Zea mays L.–Triticum aestivum L.–Zea mays L.–Avena sativa L.) was planted and two irrigation treatments (traditional and improved) were applied only to the corn. In an experimental set-up of 24 plots, samples of the soil solutions were extracted 61 times during the experiment at soil depths of 0.4, 0.9 and 1.4 m. During the experiment, drainage volume was estimated in plots under the two irrigation schedules. Main ions in the soil solution were SO₄²⁻, Cl⁻, Ca²⁺, Na⁺ and HCO₃⁻. These solutes accounted for 88% of total salt discharge under the two irrigation treatments. Two main patterns of salt leaching were observed. For most main ions, except HCO₃⁻, the input to discharge ratio was lower than one. Also for HCO₃⁻ , the irrigation treatment did not affect the leaching pattern (higher input than discharge under the two irrigation treatments). Improved irrigation schedules can be implemented without increasing the total salt load, but attention should be paid to specific leaching patterns of individual ions.     

Spatial and Temporal Variability of Total Non-Residual Heavy Metals Content in Stream Sediments from the Suquia River System,Cordoba, Argentina

The Suquía is a semiarid (rainfall, 700-900 mm y-1), medium-size (7700 km2) riversystem located in central Argentina. Its mountainous upper catchment includes pristine areas aswell as a variety of human settlements and a reservoir lake. A large city (Córdoba, ca. 1.3million inhabitants) and a terminal hypersaline lake are included in the middle and lower basin.Total non-residual (TNR) heavy metals (Pb, Cu, Ni, Zn, Mn, and Fe) have been determined inriver bed sediments in two seasons (spring and autumn), seeking to establish the factors whichcontrol the temporal and spatial variability. The major findings were: a) concentrations of TNRmetals were, in general, higher during springtime than during autumn, particularly downstreamfrom the city of Córdoba; b) organic matter played a significant role as a controlling factorwherever it defined reducing conditions, lowering the concentrations of Mn and Fe hydrousoxides; c) a higher organic load (e.g., downstream the city) and more pronounced reducingconditions could be the causes for the increased Fe concentration, probably precipitated assulfides; d) organic matter exhibited a closer correlation with some TNR metals in autumn,probably caused by a larger capacity for complexation in the biologically-processed organicdebris; and, e) the existence of pristine areas in the drainage basin allowed for the calculation ofenrichment factors (EF) which show the significance of several environmental impacts in theSuquía system.     

Rye genetic resources evaluation in the Botanical Garden of the Polish Academy of Sciences in Warsaw

Summary The new Botanical Garden of the Polish Academy of Sciences was established in 1974 as an institution dedicated to collecting, conserving, and evaluating crop genetic resources and their wild progenitors. The main object of this research is rye (Secale L. spp.) — the cereal of great importance to Poland. The genetic resources of rye are preserved in living field collections, as well as in a seed stock bank. The living collection contains 1.193 taxa, including 12 species ofSecale and 788 different rye cultivars. The seed bank stores 773 taxa of rye kept in glass containers (in vacuum, neutral gases or with silica gel) with optimum low moisture content in the seeds. Biochemical, physiological and genetical investigations are carried out for the estimation of safe and suitable conditions of seed dehydration and long term storage. These genetic resources of rye serve as material for taxonomic and phylogenetic studies, as well as for the evaluation of their selected breeding properties, especially seed protein content and its nutritional value. The taxonomic studies are performed using the isoenzyme technique and numerical methods. The enzymatic variation within the rye species, cultivars and inbred lines, are analysed. For the protein resources evaluation, different techniques are applied: the histochemical staining of seed slices. scanning electron microscope observations, and the chemical analyses of the entire amino acid composition of seed proteins. These results are used to select the most valuable taxa, which are then proposed to be used in the rye breeding programme.

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Beurteilung der genetischen Ressourcen des Roggens im Botanischen Garten der Polnischen Akademie der Wissenschaften in Warschau

Zusammenfassung Der neue Botanische Garten der Polnischen Akademie der Wissenschaften wurde 1974 als eine Institution gegründet, die sich der Sammlung, Erhaltung und Beurteilung der genetischen Ressourcen von Kulturpflanzen und deren Wildformen widmen soll. Hauptgegenstand dieser Untersuchung ist der Roggen (Secale L. spp.) — ein Getreide, das für Polen von großer Bedeutung ist. Die genetischen Ressourcen des Roggens werden sowohl in lebenden Sammlungen auf dem Felde als auch in einer Samenbank erhalten. Die lebende Sammlung enthält 1193 Taxa (12 Roggen-Arten und 788 Roggen-Sorten). Die Samenbank umfaßt 773 Roggen-Taxa in Glasbehältern (im Vakuum, neutralen Gasen oder Silikagel) mit optimal niedrigem Samenfeuchtigkeitsgehalt. Biochemische, physiologische und genetische Untersuchungen werden durchgeführt zur Ermittlung sicherer und passender Bedingungen der Samenentwässerung und Langzeitlagerung. Diese genetischen Ressourcen des Roggens dienen als Material für taxonomische und phylogenetische Studien sowie für die Beurteilung ihrer züchterischen Eigenschaften, besonders Eiweißgehalt der Samen und sein Nährwert. Bei den taxonomischen Studien werden die Isoenzym-Technik und numerische Methoden angewendet. Die enzymatische Variation innerhalb der Roggen-Arten, -Sorten und -Inzuchtlinien werden untersucht. Für die Beurteilung der Protein-Ressourcen werden verschiedene Techniken angewendet: histochemische Färbung von Samenschnitten, Beobachtungen mit dem Raster-Elektronenmikroskop und chemische Analysen der gesamten Aminosäure-Zusammensetzung der Samen-Proteine. Diese Ergebnisse werden benutzt, um die wertvollsten Taxa aufzufinden, die dann zur Anwendung in Roggen-Zuchtprogrammen vorgeschlagen werden.

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Impact of soil pressure and compaction on tracheids in Norway spruce seedlings

We tested the effect of soil compaction on Norway spruce seedlings in terms of the size and theoretical volume flow rate of the tracheids. The results show that soil pressure limits growth in the diameter of the lumens of tracheids in all parts of seedlings studied. The tracheids of the roots with primary xylem had larger lumens than those of the roots and shoots with secondary xylem in both unloaded and loaded seedlings. This corresponds to the higher cumulative theoretical volume flow rate of the tracheids from roots with primary xylem than those from roots and shoots with secondary xylem. Although the volume flow rate of tracheids, according to the Hagen-Poiseuille law, was directly proportional to the quadratic power of the capillary diameter (tracheid lumen), the cumulative curve of the theoretical hydraulic volume flow rate was higher or relatively comparable in loaded seedlings. An explanation for these findings is that there were higher gradients of water potential values in roots and leaves in loaded seedlings because the lengths of the conductive pathways were 27% shorter than in unloaded seedlings. We hypothesise that trees have adapted to different stresses by shortening their conductive pathways to maintain a transpiration rate similar to that of non-stressed trees. These results concerning the impact of soil compaction on tracheid diameter and volume flow rate improve our understanding of the growth and functioning of different conifer organs and the mechanisms underlying the efficiency of water transport through the root xylem to the shoot.