Analysis of the phenotypic variability of twenty f3 biparental populations of bread wheat (Triticum aestivum L.) evaluated under semi-arid environment

This research was conducted to screen and analyse the variability within twenty F3 populations of bread wheat (Triticum aestivum L.) generated by Line x Tester mating design. The results indicated the presence of sufficient variability within and between F3 populations for the eight measured variables, which represent plant phenology, physiology, yield and yield components. Different populations have been identified to improve the measured variables separately. The number of spikes appeared to be the most important determinant of grain yield. PCA and cluster analyses indicated that the Acsad1069/El Wifak and Acsad1135/Hidhab, with a relatively high grain yield,  aboveground biomass and 1000 grains weight, are the best F3 populations to improve the productivity. However, Acsad899/Rmada and Acsad1135/Rmada populations were earlier and had a low number of spikes. These populations had also favorable genes for heat tolerance.Keywords: Triticum aestivum L.; Variability; Selection; Tolerance; Yield

Analysis of the phenotypic variability of some varieties of durum wheat (Triticum durum Desf) to improve the efficiency of performance under the constraining conditions of semiarid environments

The experiment was conducted during three growing seasons and two planting dates. The cultivation site is placed at the ITGC Setif characterized by a semi-arid environment. The objective of the study is the analysis of phenotypic variability of traits measured for 15 varieties of durum wheat, through the average effects, to decline the ways, characters and varieties could play in favour of performance under the constraining semi-arid conditions. The year effect indicates that given the difficulty of predicting the performance enabled by years, it then makes sense to go straight for this performance within genotypes. Analysis of the effect genotype highlights characters connected to performance and is the Setifis variety that lends itself well. For the effect of sowing date, it is that early sowing promotes a better expression of the characteristics compared to late sowing.Keywords: Effect; genotype; year; date; variation; character

Chronic Exposure to the Herbicide, Atrazine, Causes Mitochondrial Dysfunction and Insulin Resistance

There is an apparent overlap between areas in the USA where the herbicide, atrazine (ATZ), is heavily used and obesity-prevalence maps of people with a BMI over 30. Given that herbicides act on photosystem II of the thylakoid membrane of chloroplasts, which have a functional structure similar to mitochondria, we investigated whether chronic exposure to low concentrations of ATZ might cause obesity or insulin resistance by damaging mitochondrial function. Sprague-Dawley rats (n = 48) were treated for 5 months with low concentrations (30 or 300 µg kg−1 day−1) of ATZ provided in drinking water. One group of animals was fed a regular diet for the entire period, and another group of animals was fed a high-fat diet (40% fat) for 2 months after 3 months of regular diet. Various parameters of insulin resistance were measured. Morphology and functional activities of mitochondria were evaluated in tissues of ATZ-exposed animals and in isolated mitochondria. Chronic administration of ATZ decreased basal metabolic rate, and increased body weight, intra-abdominal fat and insulin resistance without changing food intake or physical activity level. A high-fat diet further exacerbated insulin resistance and obesity. Mitochondria in skeletal muscle and liver of ATZ-treated rats were swollen with disrupted cristae. ATZ blocked the activities of oxidative phosphorylation complexes I and III, resulting in decreased oxygen consumption. It also suppressed the insulin-mediated phosphorylation of Akt. These results suggest that long-term exposure to the herbicide ATZ might contribute to the development of insulin resistance and obesity, particularly where a high-fat diet is prevalent

Evaluation of grain yield performance of seven (Triticum durum Desf.) genotypes grown under semi-arid conditions during two crop seasons in the eastern of Algeria

Abstract. The aim of this study was to test the adaptability of seven (Triticum durum Desf.) genotypes grown under semi-arid conditions. The experiment was carried out at the Agricultural Experimental Station of Setif (Algeria), in a design of random blocks with three replications; the plant material used in this study consisted of seven genotypes (Triticum durum Desf.). At maturity, the following parameters were measured: grain yield; economic yield; above ground biomass; number of spikes per meter square; number of grain per spike; harvest index; thousand kernel weight and plant height. Number of days to heading was accounted from sown date. ANOVA showed that genotype and crop season effect were highly significant with all traits studied. MBB and Boussellem genotypes were the most suitable genotypes; they had good ranking under both crop seasons according to their results for all traits studied. 2016/2017 was the best crop season; it recorded the best values of grain yield and the majority of the traits studied. The interaction genotype X crop season was highly significant for all traits studied.The correlations among traits under both crop season showed that grain yield was significantly correlated with economic yield and number of grains per spike. A high significant correlation was observed between economic yield and above ground biomass under both crop seasons. Number of days to heading was significantly correlated with plant height under both crop seasons

Stability analysis for grain yield and thousand kernel weight of durum wheat (Triticum durum Desf.) genotypes growing under semi-arid conditions

Abstract. The present study was carried out to select adapted and stable durum wheat (Triticum durum Desf.) genotypes for grain yield and thousand kernel weight using various stability parameters. Based on the graphical distributions between the parametric indices (Wricke’s ecovalence stability index (Wi²), environmental coefficient of variance (CVi), mean variance component (θi )) and the mean grain yield of tested genotypes, the suitable genotype for the tested conditions was Mexicali 75. Further, the cultivars Oued Zenati and Bousselem were the most adapted with the highest TKW. With non-parametric index was classified genotype Mexicali 75 as the most stable with high grain yield. According to PCA analysis the genotype Altar 84 was classified in dynamic stability group with the highest grain yield in addition, cultivars Bousselem and Oued Zenati were classified in dynamic concept with the highest thousand kernel weight. The results of this study confirmed that the parametric and non-parametric methods are the suitable tools to identify the most stable durum wheat (Triticum durum Desf.) under semi-arid conditions

Toxicity of 4-chloroaniline in early life-stages of zebrafish (Danio rerio): II. Cytopathology and regeneration of liver and gills after prolonged exposure to water-borne 4-chloroaniline

Ultrastructural alterations in liver and gills of embryonic and larval zebrafish (Danio rerio) following prolonged exposure to waterborne 0.05, 0.5, and 5 mg/L 4-chloroaniline for up to 31 days as well as after a 14-day regeneration period were investigated by means of light and electron microscopy. Acute toxicity was also tested at 25 and 50 mg/L. Survival of zebrafish embryos and larvae was only impaired from 25 mg/L 4-chloroaniline, but—after a transient stimulation following exposure to 0.5 mg/L—4-chloroaniline hatching was retarded after exposure to ≥5 mg/L, and fish displayed increasing rates of abnormal development and pigmentation. In contrast, hepatocytes displayed a time- and dose-dependent response from 0.05 mg/L 4-chloroaniline, including changes in nuclei, mitochondria, peroxisomes, endoplasmic reticulum, Golgi fields, lysosomes, and hepatic glycogen and lipid stores, as well as invasion of macrophages. In gills, dose-dependent effects were evident from 0.5 mg/L 4-chloroaniline and included deformation of secondary lamellae due to vacuolization and desquamation of respiratory epithelial cells in conjunction with dilation of intercellular spaces. Respiratory epithelial cells displayed progressive mitochondrial changes, induction of cytoplasmic myelinated structures, augmentation of lysosomes, and modifications of Golgi fields. Erythrocytes were severely deformed. A 14-day regeneration period was sufficient for almost complete recovery of pathological symptoms in both liver and gills. Only minor volumetric changes in hepatocellular organelles and a limited number of myelinated bodies, lysosomes, and cytoplasmic vacuoles were reminiscent of prior 4-chloroaniline exposure. In both qualitative and quantitative terms, most effects in hepatocytes after exposure of embryonic and larval zebrafish to waterborne 4-chloroaniline are comparable to the reaction of hepatocytes in adult zebrafish liver after prolonged sublethal exposure as well as in larval zebrafish after microinjection. Morphological changes in erythrocytes indicate disturbance of respiration as an additional mode of action of 4-chloroaniline

Isolation of actinomycetes producing bioactive substances from water, soil and tree bark samples of the northeast of Algeria

International audienceTwenty-five strains of actinomycetes were isolated from samples of water, soil and tree barks collected at two sites located in the northeast of Algeria. Antimicrobial activity was tested using the agar cylinder method against three Gram-positive bacteria, three Gram-negative bacteria, three yeasts and three filamentous fungi. Among the 25 isolates 14 (56%) strains showed an activity against at least one of the test-bacteria studied and two (8%) showed antifungal activity. Ninety-three percent of the active strains were identified by the universal PCR as belonging to the Streptomyces genus and 7% to the Actinomadura genus

Biphasic (Janus), Core–Shell and Functionalized Magnetic Polymer Particles: A Route of Synthesis to Application

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