41 research outputs found
PLS âFTIR - crude fiberâ model for forages from hill permanent grassland
In this study was obtain a FTIR calibration model to predict the crude fiber content of forages harvested in period
October 2007 - August 2009 from hill permanent grassland (GrÄdinari, CaraĆ-Severin District). The forages samples
were purchased in different vegetation stages, considering also that experimental field was organized in ten
experimental trials fertilized organic, mineral, and organo-mineral. The floristic composition of forages was determined
gravimetrically. From Poaceae were present Festuca rupicola and Calamagrostis epigejos. Fabaceae family was
represented by Trifolium repens and Lathyrus pratensis. From other botanical family: Rosa canina, Filipendula
vulgaris, Galium verum and Inula britanica.
To obtain the calibration model âFTIR-CFâ was used the results for this parameter by chemical method and the
reflectance values from FTIR spectra, only for the 4 selected ranges. Partial last square (PLS) regression was used to
obtain the calibration model, implemented in Panorama program (version 3, LabCognition, 2009). The statistical
parameters R2
=0.8167 and RMSEC=2.5315, and the differences between chemical results and predicted values suggest
that it is promising to develop FTIR models to predict the crude fiber contents of forages from grassland
First derivative in NIR spectroscopy calibration for protein content of forages from hill permanent grassland
The aim of this study was to perform a NIR calibration model for crude protein content determination of forages using first derivative of 294 spectra and chemical Kjeldahl values. The forages samples were harvested in June from hill permanent grassland (GrÄdinari, CaraÈ-Severin District), fertilized with sheep manure and/or mineral fertilizers. The annual average temperature in this region was around 10.4oC and the soil Calcic Luvisol. The fermented sheep manure was applied at each two years, while the mineral fertilizers yearly, since 2003. The matrix of floristic composition was established gravimetrically. PLS (Partial Least Squares) regression, implemented in Panorama program (version 3, LabCognition, 2009), was used to obtained the âNIR-CPâ model. The statistical parameters (R2=0.9303; RMSEC=0.88; SD=3.11) and the differences between predicted and references values make promising this calibration model for practice evaluation of crude protein content for forages from grassland harvested in this period of year
Snail survival as bioindicator of cadmium contaminated soils under semi-realistic field conditions
Juvenile brown garden snails (Helix aspersa MĂŒller) were exposed to Cd-contaminated soils for 60 days
under semi-realistic field conditions. The soils were contaminated with increasing concentrations of cadmium
chloride (0â2900 mg kg-1 Cd2+/solution CdCl2). The snails were housed in terrariums and were fed
exclusively with nettle leaves. The experiments were carried out in Timisoara on 1000 snails.The survival
rates differed significantly for different Cd treatments. Only higher cadmium concentrations (> 1000 mg kg-1
Cd2+/solution CdCl2) had a significant influence on survival curves of snails exposed to Cd-contaminated
soils. The maximal death rate reached 81.00±9.9% for snails exposed to soils contaminated with 2900 mg kg1
Cd /solution CdCl2. We found dose-dependent survival rates, whereas the half maximal effective
concentration was 1365 mg kg-1 Cd2+/solution CdCl2. Our results suggested that longer-term studies are
required for assessing the real potential of snail survival rate as bioindicator of Cd-contaminated soils in field conditions
High-level dietary cadmium exposure is associated with global DNA hypermethylation in the gastropod hepatopancreas
5-methylcytosine (5mC) is a key epigenetic mark which influences gene expression and phenotype. In vertebrates, this epigenetic mark is sensitive to Cd exposure, but there is no information linking such an event with changes in global 5mC levels in terrestrial gastropods despite their importance as excellent ecotoxicological bioindicators of metal contamination. Therefore, we first evaluated total 5mC content in DNA of the hepatopancreas of adult Cantareus aspersus with the aim to determine whether this epigenetic mark is responsive to Cd exposure. The experiment was conducted under laboratory conditions and involved a continuous exposure, multiple dose- and time-point (14, 28, and 56 days) study design. Hepatopancreas cadmium levels were measured using Flame Atomic Absorption Spectrometry and the percentage of 5-mC in samples using an ELISA-based colorimetric assay. Snail death rates were also assessed. Our results, for the first time, reveal the presence of 5mC in C. aspersus and provide evidence for Cd-induced changes in global 5mC levels in DNA of gastropods and mollusks. Although less sensitive than tissue accumulation, DNA methylation levels responded in a dose- and time-dependent manner to dietary cadmium, with exposure dose having a much stronger effect than exposure duration. An obvious trend of increasing 5mC levels was observed starting at 28 days of exposure to the second highest dose and this trend persisted at the two highest treatments for close to one month, when the experiment was terminated after 56 days. Moreover, a strong association was identified between Cd concentrations in the hepatopancreas and DNA methylation levels in this organ. These data indicate an overall trend towards DNA hypermethylation with elevated Cd exposure. No consistent lethal effect was observed, irrespective of time point and Cd-dosage. Overall, our findings suggest that the total 5mC content in DNA of the hepatopancreas of land snails is responsive to sublethal Cd exposure and give new insights into invertebrate environmental epigenetics
Evaluation of iron content in the grain of some winter wheat cultivars
The purpose of the research is to follow the influence of the biological factor on iron content of nine varieties
of winter wheat: Alex, Potenzial, Soissons, Kalango, Apache, Kristina, Lovrin 34, Chevalier and Panonnikus.
Two of these (Potenzial, Chevalier) are of German origin, three (Apache, Kalango, Soissons) of French
origin, one (Kristina) of Yugoslavian origin, one of Austrian origin (Panonnikus) and two (Alex and Lovrin
34) were created at S.C.D.A Lovrin, Romania. The experimental field was placed on a cambic chernozem in
Timisoara (west of Romania) in 2010, and the fertilization level was N120P60K60. Quality parameters
monitored were: moisture, protein content, hectolitre mass and iron content. Variation in the iron content of
different winter wheat cultivars was found in this study. Soissons winter wheat cultivar registered the highest
value of iron content (54.3 mg/kg dry matter) followed by Kristina (52.07 mg/kg dry matter) and Kalango
(50.45 mg/kg dry matter) winter wheat cultivar. Potenzial and Apache winter wheat cultivars registered the
lowest values of iron content: 21.29 (mg/kg dry matter) and 20.5 (mg/kg dry matter), respectively
Mineral content of different winter wheat cultivars
In the present study the contents of Cu, Mn and Zn were investigated in the grains of different winter wheat
(Triticum aestivum L.) cultivars. The nine varieties of winter wheat were: Potenzial, Kalango, Apache, Soisson,
Kristina, Chevallier, Panonnikus, Alex and Lovrin 34. The experimental field was placed in 2009-2010
agricultural year, on a cambic chernozem in Timisoara (west of Romania) with the fertilization level N120P60K60.
For this goal, the mineral elements mentioned were quantified by Atomic Absorption Spectrophotometry (AAS)
and for their determination was used the atomic absorption spectrophotometerâs contr AA 300, Analytik Jena.
The high contents of Cu were registered by Kalango, Panonikus and Soisson winter wheat cultivars and the
lower contents by Potenzial and Apache. Regarding Zn content, Soisson had the greatest value and Apache the
lowest value of this parameter. With the exception of Apache winter wheat cultivar, all the varieties registered
high values of Mn content. Results of our study demonstrated that mineral content for winter wheat cultivars is strongly influenced by the biological factor