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Powdery mildew, caused by Blumeria graminis f. sp. hordei (Bgh) is a common foliar disease of barley worldwide. The creation of new cultivars with durable resistance to Bgh is highly desirable. This work was undertaken to examine the resistance to Bgh in 10 genetically diverse barley parents, and to evaluate their general combining ability (GCA) and specific combining ability (SCA) effects toward determining the genetic basis of disease resistance. Two experiments, in a growth chamber on seedling and in the field on adult plant stages, were conducted using a randomized complete block design with three replicates. The parents expressing differences in their reactions to Bgh were crossed in a half-diallel mating design to generate 45 full-sib families. Genetic component analysis showed significant effects for both GCA and SCA under both experiments suggesting that additive as well as non-additive genetic mechanisms were involved in the expression of resistance in these parents. The estimate of narrow-sense heritability was 0.63 and broad-sense heritability was 98% indicating that selection for the disease resistance should be effective in these crosses. Resistant parents ‘Banteng, PK 30-136 and ‘Igri’ had significantly negative GCA effects, suggesting their prime suitability for use in barley breeding programs to improve resistance to Bgh.

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Glyphosate (N-(phosphonomethyl)glycine) is the most-used herbicide worldwide. Many studies in the past have shown that residues of the herbicide can be found in many cultivated plants, including those used as livestock feed. Sensitivity to glyphosate varies with bacteria, particularly those residing in the intestine, where microbiota is exposed to glyphosate residues. Therefore, less susceptible pathogenic isolates could have a distinct advantage compared to more sensitive commensal isolates, probably leading to dysbiosis.

To determine whether the ruminal growth and survival of pathogenic Escherichia coli or Salmonella serovar Typhimurium are higher when glyphosate residues are present in the feed, an in vitro fermentation trial with a “Rumen Simulation System” (RUSITEC) and a glyphosate-containing commercial formulation was performed.

Colony forming units of E. coli and Salmonella ser. Typhimurium decreased steadily in all fermenters, regardless of the herbicide application. Minimum inhibitory concentrations of the studied Salmonella and E. coli strains did not change, and antibiotic susceptibility varied only slightly but independent of the glyphosate application.

Overall, application of the glyphosate-containing formulation in a worst-case concentration of 10 mg/L neither increased the abundance for the tested E. coli and Salmonella strain in the in vitro fermentation system, nor promoted resistance to glyphosate or antibiotics.

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Elevated oxidative stress in type 2 diabetes mellitus (T2DM) has been proposed as one of the major risk factors in pathophysiology of several organ damages including liver tissue.

Materials and methods

In this study, we evaluated the effect of swimming training on hepatic oxidative markers, SIRT1 gene expression, and histological alterations in T2DM. Twenty-eight male Wistar rats were randomly assigned into four groups (N = 7): control, exercise, diabetic, and diabetic + exercise. One week after the induction of T2DM, rats were subjected to swimming (60 min/5 days a week) for 12 weeks. At the end of the experiment, oxidative markers (SOD, GPx, CAT activities, and MDA level) and SIRT1 gene expression were measured in the liver by special kits and RT-PCR, respectively. Hematoxylin–eosin statins were used for histological alterations.


Swimming training attenuated MDA levels and enhanced SOD, GPx, and CAT activities in the liver of diabetic animals. Furthermore, swimming training restored the expression of SIRT1 in T2DM. Histopathological finding of the hepatic tissue confirmed a protective role for swimming training in diabetic rats.


Our findings indicate that swimming training attenuates oxidative stress probably by upregulation of SIRT1 in the liver of type 2 diabetic rats.

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Salt stress is one of the major abiotic stress which severely limits plant growth and reduces crop productivity across the world. In the present study, the effects of exogenous pyridoxal-5-phosphate (vitamin B6, VB6) on seedling growth and development of wheat under salt stress were investigated. The results showed that exogenous application of pyridoxal-5-phosphate (VB6) significantly increased the RWC, biomass, the concentration of photosynthetic pigments, proline, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), together with decreasing the content of Malondiadehyde (MDA) and hydrogen peroxide (H2O2) in wheat leaves under salt stress. Meanwhile, the transcript level of P5CR, P5CS, SOD, TaSOS1 and TaSOS4 were also up-regulated after treatment with pyridoxal-5-phosphate. VB6 acts as a signal in regulating the activities of plant antioxidant enzymes and SOS pathway to improve resistance to salt stress. The current study results may give an insight into the regulatory roles of VB6 in improving salt stress and VB6 could be an easily and effective method to improve salt-stress tolerance to wheat in the field condition. It is urgency to understand the molecular mechanism of VB6 to enhance the salt tolerance of wheat in the next work.

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Biologia Futura
Authors: Arne Thell, Mats Hansson, Per-Erik Persson, Mark R. D. Seaward, Maik Veste, and Mikael Hedrén

Background and aims

Betony (Betonica officinalis L.) is one of the rarest and most spectacular plants in the Scandinavian flora. A long-term question has been whether it is spontaneous or introduced, or whether it comprises both spontaneous and introduced populations. This study aimed to answer this question by analyzing sequence data from the nuclear external transcribed spacer (ETS) region and three regions of the plastid genome, the trnT–trnL intergenic spacer (IGS) region, tRNA-Leu (trnL) intron, and the trnS–trnG IGS.

Materials and methods

Altogether 41 samples from 11 European countries were analyzed. A unique duplication in the trnT–trnL IGS was detected in material from Skåne (southern Sweden), the “Skåne-duplication.” Populations with this duplication are united on a moderately supported branch in the phylogeny based on plastid sequences. A distinct heath genotype from Yorkshire was discovered in the phylogeny based on plastid sequences and in a comparative cultivation.


Phylogeny based on ETS sequences does not support any Scandinavian group, whereas a principal coordinates analysis ordination based on variable ETS positions indicated a spontaneous origin for all Scandinavian populations, which comprise a genetically well-defined subgroup of the species, most closely related to other spontaneous populations from adjacent parts of continental parts of northern Europe.


Seven possible naturally occurring localities remain in Scandinavia, five in central Skåne, southernmost Sweden, and two on the southwestern part of the Danish island of Lolland.

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The impact of trinexapac-ethyl (TE) on salinity subjected wheat plants was evaluated via pot based experiment. The treatments applied to wheat seedlings included (Ck) control (no NaCl nor TE spray), foliar spray of TE (1.95 ml L−1), only NaCl (50 mM) and NaCl+ TE (50 mM + 1.95 ml L−1). Foliar application of TE was done seven days after imposition of salinity. Growth parameters (root length, shoot length, fresh weight, and dry weight) and photosynthetic pigments content (chlorophyll a, b, a + b and a/b), water relation (water potential, osmotic potential, turgor potential and relative water contents) as well as catalase (CAT) activity exhibited marked reduction in comparison to control. In addition, an increment was noted in organic solutes content (proline, soluble protein and soluble sugar) and enzyme activity of superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) in stressed seedlings over control seedlings. The foliar applied TE mostly enhanced growth of salt stressed seedlings, accompanied by reinforcement in photosynthetic pigments, organic solutes, and enzyme activity (SOD, CAT, POD, and APX) in comparison to stressed seedlings. It is worthy to mention that, TE has potential to enhance salt tolerance of wheat seedlings. Thus, our findings suggest that seedling treated with TE is an effective strategy that can be used to enhance salt tolerance of wheat crop.

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A study was conducted to evaluate the antioxidant enzymes activity, proximate and nutritional composition of four medicinal plants, which may contribute to folk pharmacological use in the treatment of different diseases. Plant samples were extracted and antioxidant enzymes like superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO) and ascorbate peroxide (APX) activity were estimated. Medicinal plants were also analysed for moisture, ash, protein, fibre, carbohydrate, and fats contents. Plant samples were wet digested and mineral composition in terms of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na) was determined. The results revealed that antioxidant activity, proximate and nutritional composition differs significantly among tested medicinal plants extract. The leaves of medicinal plants showed more proximate composition (moisture contents, crude protein, fats contents), nutrient accumulation (N, P, K, Ca, Mg and Na), and antioxidant enzymes (POD, PPO, and APX activity). Among medicinal plants, Tribulus terrestris L. showed the highest amount of crude protein, crude fibre, gross energy, and N and Ca contents. Maximum K, Mg, Na contents, POD, PPO and APX activity was observed in Cenchrus ciliaris L. The ash, fats, phosphorus and SOD activity was more in Euphorbia hirta L. While, Cyperus rotundus L. produced maximum carbohydrates concentration among the tested plants. It is concluded that the target medicinal species had emerged as a good source of the antioxidant and nutritive source, which could play an important role in human nutrition. The extracts of these plants parts can be used in the synthesis of mineral and antioxidant-containing drugs and medicines. This study will provide a baseline for the pharmacology industry.

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The genus Hypericum (Hypericaceae) consists of 484 species from 36 sections with worldwide distribution in different areas. Turkey is considered as hot spot for diversity of Hypericum genus. Despite numerous publications, Hypericum species still attracted considerable scientific interest due to pharmaceutically relevant secondary metabolites: naphthodianthrones, acylphloroglucinol derivatives, phenolic acids, flavonoid glycosides, biflavonoids, and some other valuable constituents. Phytochemical investigations carried out on different Hypericum species provided highly heterogeneous results. The content of bioactive compounds varies significantly due to many internal and external factors, including plant organs, phenological stage, genetic profile, environmental abiotic and biotic factors, such as growing site, light, temperature, radiation, soil drought and salinity, pathogens, and herbivores attack. The variations in content of bioactive compounds in plants are regarded as the main problem in the standardization of Hypericum-derived pharmaceuticals and dietary supplements. The review discusses the main factors contributing to the variations of bioactive compounds and what kind of modulations can increase quality of Hypericum raw material.

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Genotype selection based on multiple traits in multi-years is frequently influenced by unpredictable rainfed conditions. The main objective of the study was to apply the new methodology of genotype by yield*trait (GYT) biplot for genotype selection and trait profiles in durum wheat genotypes based on multi-traits and multi-year data under rainfed conditions of Iran. A superiority index was applied based on GYT table for ranking of genotypes by the mean of all traits. The GYT biplot ranked the genotypes based on their levels in combining yield with other key traits. Grain yield was combined with target traits and showed the strengths and weaknesses of each genotype. Based on GYT-biplots the relationships among the studied traits were not repeatable across years, but they facilitated visual genotype comparisons and selection. The breeding lines G13, G10 and G15 ranked as the best in combination of the morph-physiological traits i.e., SPAD-reading, early heading, flag-leaf length and number of grain per spike with grain yield under rainfed conditions. The results indicate that there is a potential for simultaneous improvement of some characteristics of durum wheat under rainfed conditions. The GYT biplot was a useful tool for exploring the combination of yield with traits and trait profiles of the durum genotypes to obtain high genetic gains in the durum breeding programs.

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Guettarda sierrae, a new species from the NE coastal fringe of Cuba, is described and compared with other species of the genus occurring in Cuba. Aspects of its distribution and conservation status are discussed. A lectotype for Guettarda undulata, a Cuban species related to Guettarda sierrae, is proposed herein.

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