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Content Values (content + value)
Selected AbstractsVariation in leaf traits through seasons and N-availability levels and its consequences for ranking grassland speciesJOURNAL OF VEGETATION SCIENCE, Issue 4 2005Raouda Al Haj Khaled Abstract Question: Are leaf dry matter content, specific leaf area and leaf life span relevant plant traits to discriminate the fertility gradient in species-rich natural grasslands? In other words, is species ranking conserved when nitrogen availability or growing periods change? Location: Toulouse Research Centre, France; 150 m a.s.l. Methods: Fifteen grasses and nine dicotyledons were sown in pure stands in a random block design with three replicates. Each species was cultivated at two levels of nitrogen supply, limiting and non-limiting for growth, with three replications per nitrogen level. Leaf traits were measured across both levels of nitrogen supply and growing periods over the year. Results: Leaf dry matter content values separated the species into three life-form classes (grasses, rosette forbs and upright forbs, P < 0.001). This was not the case for specific leaf area and leaf life span. The three leaf traits were variable across growing periods and nitrogen levels, but the ranking of species was conserved over N-levels and growth periods. Furthermore leaf dry matter content was always less variable than the other leaf traits. Conclusion: We conclude that leaf dry matter content measured only on grasses could be used as an indicator to describe the N-richness of the habitat where native herbaceous vegetation develops. [source] Preparation and Characterization of Hyperbranched Polymer/Silica Hybrid Nanocoatings by Dual-Curing ProcessMACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2006Ezio Amerio Abstract Summary: Organic-inorganic nanocomposite hybrid coatings were prepared through a dual-cure process involving cationic photopolymerization of a hyperbranched epoxy functionalized resin and subsequent condensation of an alkoxysilane inorganic precursor. All the formulations investigated gave rise to photocured films characterized by high gel content values. An increase in glass transition temperature and an increase in storage modulus above Tg in the rubbery plateau is observed with increasing TEOS content in the photocurable formulation. The important role of GPTS on reducing the inorganic domain size and avoiding macroscopic phase separation was demonstrated by TEM analyses. TEM obtained for one of the cured films in the presence of GPTS. [source] Mineral solubility of Panicum maximum with four herbaceous forage legume mixtures incubated in the rumen of N' Dama steersANIMAL SCIENCE JOURNAL, Issue 3 2009Festus T. AJAYI ABSTRACT This study was designed to determine the mineral concentration and bioavailability of iron (Fe), phosphorus (P), calcium (Ca) and sodium (Na) of mixtures of Panicum maximum (Panicum) with Lablab purpureus (Lablab), Centrosema pubescens (Centro), Stylosanthes guianensis (Stylo), and Aeschynomene histrix (Histrix) in a fistulated N'Dama steer. The solubility of minerals was determined by an in sacco method by incubating ground samples of these forages in the rumen at 0, 6, 12, 24, 48 and 72 h. The mineral solubility characteristics of the forages were evaluated using the equation PD = a + b (1 , e,ct). The result showed that Panicum intercropped with legumes had better crude protein (CP) (av. 9.22% DM) and ash content (av. 2.22% DM) than sole Panicum which gave 7.63% DM and 1.84% DM for CP and ash contents respectively. The highest value of CP of 23.29% DM and ash content (3.96% DM) was obtained for Lablab. The mineral content values of the intercrop were higher than the sole Panicum. Higher mineral content values were obtained in the sole legumes. Iron solubility values of b and potential degradation (PD) which were 58.71% and 87.92% respectively were for Panicum/Histrix mixtures. Calcium solubility values ranged from 30.0% in Panicum to 46.0% in Panicum/Lablab mixture for b fraction. P solubility ranged from 28.0% and 46.0% for b and PD fractions in Panicum to 43.0% and 71.0% in Panicum/Centro mixture respectively. The solubility of the legumes was higher in Na for b fraction (av. 42.0%) and PD fraction (av. 60.0%). Higher values of b (av. 38.0%) and PD (av. 52.0%) were obtained for the mixtures than for sole Panicum. This study revealed that intercropping Panicum with either of the herbaceous forage legumes used for this experiment would increase the Ca, P, Na and Fe contents of the grass. [source] Genetic diversity in a collection of old and new bread wheat cultivars from Iran as revealed by simple sequence repeat-based analysisANNALS OF APPLIED BIOLOGY, Issue 1 2009S.A. Mohammadi Abstract Genetic diversity in a collection of 70 bread wheat (Triticum aestivum) genotypes was studied using 73 microsatellite [simple sequence repeat (SSR)] loci evenly spaced on wheat chromosomes. A total of 592 alleles with an average of 8.53 allele/locus were detected, of which 185 (31.25%) occurred only in a specific group of genotypes. A set of SSR markers consisted of 22 loci with polymorphic information content values of 0.80 or higher were selected for rapid fingerprinting of many genotypes. Average of gene diversity was 0.74 ± 0.017, and significant difference between observed and maximum theoretical values of gene diversity in the analysed SSR loci was obtained using a paired t -test. Genetic distance-based clustering methods including unweighted pair group method with arithmetic average and neighbour joining (NJ) were used for grouping of genotypes. The resulted dendrogram based on NJ and number of differences coefficient hinted of the existence of three groups. This grouping was in agreement with the pedigree information and confirmed by high within-group bootstrap value. A comparatively higher genetic diversity in the studied wheat collection as revealed by presence of high allelic diversity and large number of specific alleles could be utilised in development of new cultivars with desired characteristics. [source] Investigation of fat content in market common carp (Cyprinus carpio) flesh during the growing seasonAQUACULTURE NUTRITION, Issue 5 2010M. URBÁNEK Abstract Effects of supplemental feeding with cereals (rye, triticale, maize and the unsupplemental control group) on fat content in flesh of 3-year-old common carp (Cyprinus carpio) were the subject of study carried out at four ponds (Czech Republic, Central Europe) during the growing season. The main result was that supplemental feeding with cereals to the same energetic level was associated with varying growth and fat content in the flesh of common carp. At the end of the experiment, the stock of fish supplementally fed with maize was found to have the highest fat content (112.7 ± 15.6 g kg,1), while the lowest value of fat content was found in the control group (56.8 ± 9.4 g kg,1). The carps supplementally fed with rye were found to have a higher fat content (90.1 ± 19.0) than those supplementally fed with triticale (84.3 ± 15.7 g kg,1). Established average fat content values (except for maize) were at the level that indicate a high sensory quality of carp flesh during the whole growing season. [source] | |||||||||||||