This study examined the uptake, translocation, distribution and accumulation of Cd, Zn and Fe and the interaction of these elements in winter wheat. The objectives were: (1) to characterise ...specificity among winter wheat genotypes in terms of accumulation of Cd, Zn and Fe in various organs and identify genotypes combining low accumulation of Cd with high accumulation of Zn and/or Fe, (2) to determine genetic specificity of winter wheat genotypes in terms of translocation of Cd, Zn and Fe from the vegetative parts to the grain, and (3) elucidate an effect of soil cadmium contamination on the distribution and accumulation of Cd, Zn and Fe in various organs of wheat. In the 2007/2008 vegetation season, 52 winter wheat varieties (34 Croatian, 7 Austrian, 5 Hungarian, 3 French and one variety of Russian, Italian and German descent) were investigated. The pots were arranged, according to a completely randomized design with two levels of soil Cd contamination (0 and 20 mg kg-1 soil) in four replicates. In the vegetation season of 2008/2009 the experiment was set up to a completely randomized block design with 10 varieties of wheat and three levels of soil Cd contamination (0, 2 and 5 mg kg-1 soil) in four replicates. The concentration of Cd, Zn and Fe in the solution of plant samples was determined by ICP-OES. The concentration of Cd, Zn and Fe was determined at the flowering stage in the root, stem,leaves, flag leaf and spike and in a full maturity in the straw, leaves, glumes and grain. Collected data were statistically analyzed with SAS software 9.1.3. Analysis of variance identified a statistically significant difference in the concentrations of Cd, Zn and Fe in vegetative parts and grain between the tested wheat varieties at all levels of soil Cd contamination. It was also found that the soil Cd contamination had a significant effect on the accumulation of Cd in grain while the accumulation of Zn and Fe in the grain hasn’t been influenced by soil Cd contamination. The tested genotypes differed significantly in the Cd, Zn and Fe plant uptake factor as well as in the coefficient of translocation from roots to stems and from roots to the flag leaf. According to correlation coefficient between the concentrations of Cd, Zn and Fe in the grain, the tested cultivars were divided into six groups which differ in the interrelation of these elements. Obtained results may serve as a starting point for investigation of the mechanisms of uptake, translocation and accumulation of Cd, Zn and Fe in winter wheat as well as for the selection of genotypes with increased concentrations of Zn and Fe and decreased Cd concentration in the grain.
Visualization of multivariate multidimensional data sets is a challenging task, especially without use of adequate tools and methods. In the last few years, parallel coordinate plots became quite ...popular and accepted as a very efficient multivariate visualization technique. The aim of this paper was to explore how parallel coordinates can be used in analysis of winter wheat quantitative traits. Data set is obtained from experiment set up by a completely randomized design with two treatments and four replicates. Ten variables (plant height, spike length, stem length, plant weight, spike weight, grain weight per spike, 1000 kernel weight, number of fertile and sterile spikelets per spike and total number of spikelets per spike) and fifty-five winter wheat genotypes were analysed in this paper. In parallel coordinate plots observations are shown as series of unbroken lines, passing through parallel axes, where each axes represents a different variable. Advantage of parallel coordinates, compared to other visualization techniques, is that they can represent multivariate data in two dimensions. From such representation, outliers and grouping among observations are easily detectable. Correlation among variables can also be easily detected from suchrepresentation. Although parallel coordinates cannot efficiently explore details, they are a good technique for visualization of multivariate data sets and they can be used for exploratory analysis of wheat quantitative traits.
The objective of this paper was to examine influence of sowing rate, environmental conditions and genotype on yield and traits important for yield formation (number of ears m-2, number of spikelet’s ...per ear and 1000 kernel weight) of winter wheat. Research work was conducted on five winter wheat genotypes, sown with three different sowing rates (400, 500 and 600 germinable seeds m-2), during two vegetation years. Genotypes and sowing rates had different influence on examined traits. Significant differences in yield were found in both vegetation years among examined genotypes and in one vegetation year among sowing rates. Results have sown that even with lower sowing rate it is possible to achieve high winter wheat yield and that lower sowing rates can be recommended under optimal sowing conditions.
In the planning phase of every research particular attention should be dedicated to estimation of optimal sample size, aiming to obtain more precise and objective results of statistical analysis. The ...aim of this paper was to estimate optimal sample size of wheat yield components (plant height, spike length, number of spikelets per spike, number of grains per spike, weight of grains per spike and 1000 grains weight) for determination of statistically significant differences between two treatments with significance level of 5% and statistical power of 0.8. Arithmetic means and standard deviations of winter wheat quantitative traits, statistical power, significance level α and effect size were used for calculation of optimal sample sizes. All calculations are made on data obtained from the experiment set up according to completely randomized design with two treatments in four repetitions. Optimal sample sizes for identification of ten percent difference between treatments are calculated for all traits. Retrospective power analysis was conducted for original data set of n=440 and optimal sample sizes are estimated. Obtained results showed that every examined yield component requires unique sample size. In terms of pertaining standard deviation and minimum expected difference that should be detected as statistically significant. For analyzing number of spikelets per spike sufficient sample size is 38 for effect size of 10% at significance level of 5%. Number of grains per spike and grain weight per spike (g) are the most variable traits and according to that, they have the largest estimated sample sizes (n = 440 and n = 436 respectively). Optimal sample size is mostly dependent on variability of examined trait and effect size.
The genotype-by-environment interaction (GEI), which is the differential response of genotypes to the varied environmental conditions, results from the genetic differences among varieties. The ...statistical analysis should provide estimates for parameters that indicate both how well genotypes perform on average across the environmental range and how well they perform in specific environmental conditions. AMMI models separates genotype, environment and genotype-environment interaction before applying singular value decomposition to GE for least-squares, low dimensional visualization, and they are one of foremost statistical methods in multi environment trials (MET).
This study shows results of laboratory analyses of the traits of seeds (germination and germination energy) and seedlings (root and hypocotyl length, total seedling length) of the two perennial ...ryegrass cultivars: diploid 'Bartwingo' and tetraploid 'Calibra' before and after nine months storage at the temperatures of 10°C, -20°C and -80°C in tightly sealed containers. Seed traits were significantly different at different temperatures (p=0.01). For both cultivars germination and germination energy gained the best results at -80°C in comparison to the values before storage. Obtained values of the seedling traits tested were significantly lower after 9 months storage (p=0.01). For 'Bartwingo' cultivar the slightest difference in the values of seedling traits before storage was gained at 10°C, while 'Calibra' cultivar gained the same at -20°C. After 9 months storage at different temperatures 'Bartwingo' diploid cultivar showed higher values of germination and germination energy, while 'Calibra' tetraploid cultivar developed longer root and hypocotyl length, and total seedling length. Such investigations provide opportunity of preserving perennial ryegrass seeds at lower temperatures in long term storage.
Fundamental concept of statistical process control is based on decision-making about the process on the basis of comparison of data collected from process with calculated control limits. Statistical ...process and quality control of agricultural products is used to provide agricultural products that will satisfy customer requirements in a view of quality pretension as well as costumer requirements in a cost price. In accordance with ISO 9000, quality standards for process and products are defined. There are many institutions in Croatia that work in accordance with these standards. Implementation of statistical process control and usage of a control charts can greatly help in convergence to the standards and in decreasing of production costs. To illustrate the above mentioned we tested a work quality of a nozzle at the eighteen meter clutch sprayer.
Red flour beetle Tribolium castaneum (Herbst) is a major pest of stored products. The aim of this study was to assess the potential fumigant effects of 1,8-cineole, essential oil component, on the T. ...castaneum pupae. The compound was tested in 6 doses; in two treatments (fumigation without grain and with wheat grain), exposed for 48 h, in 4 repetitions, for each gender. The compound 1,8-cineole had lethal effect on the treated pupae at both genders and in the both treatments. Total proportion of the normally developed beetles was decreased. In addition, 1,8-cineole had also a growth regulator effect, producing adultoids and deformed units, with males more susceptible. In the treatment with the grain there were significant lower dead pupae, normally developed live male beetles and also deformed female units in the stage 2. In general, compound 1,8-cineole has multiple effect against T. castaneum in pupal stage.
