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The article aims to analyze the development of the basic characteristics of the demographic dynamics in the CR in urban areas divided according to size in 1993-2004 and to express the changes in the development of the natural increase. Urban areas in the CR were divided into 3 groups according to their size (size-related groups): urban areas of up to 2 000 inhabitants - a country type, urban areas with 2 000 to 10 000 inhabitants - a transition type, urban areas with more than 10 000 inhabitants - towns. In 2004, there were 26% of inhabitants living in the country group, 20% in the transition group and 54% in towns. There was a decline in marriage rate in all the groups; in the country, with its higher level, the decline was more moderate. The divorce rate shows a moderate increase except 1999, when it dramatically fell thanks to the legislation. The divorce rate was the highest in towns and the lowest in the country. The birth rate continued its sharp decline in urban areas of all sizes during the first four years of the researched period, then it levelled off, and it has even been slightly rising in the last years. It was considerably lower in bigger towns than in the other two groups, which had practically an identical development. There was a kind of balance at the end of the period. The death rate was generally going down; it was the highest in the country areas, however, it was approximating the values in the other two groups. The dramatic fall of the natural increase levelled off and it also showed a moderate rise. Trends are expressed with polynomial functions. The article presents the characteristics development in graphs and the reasons for changes are being commented upon.

A method to obtain an oligopeptide with high Fischer ratio is described. Corn gluten meal (CGM) was hydrolysed with Alcalase 2.4L using a two-step hydrolysis. In the first-step hydrolysis, the enzyme reaction conditions for hydrolysing CGM were optimised by using the orthogonal experimental design, while pH = 8.0, temperature = 55°C, enzyme to substrate ratio (3:97, w/w), and the substrate concentration = 5% were identified as the optimum conditions, under which up to 11.62% degree of hydrolysis (DH) could be obtained. The hydrolysate was then fractionated by ultrafiltration using a membrane with the molecular cutoff of over 10 kD at 20 kPa. For the second-step hydrolysis, the filtrate was adjusted to pH 6.0, then papain was added at 50°C and the mixture was maintained for 3 hours. The hydrolysate was obtained after inactivating papain and centrifuging. Then the salt (mainly NaCl) in the hydrolysate was removed with an ion exchange resin at the speed of 8 times bed volume per hour, and aromatic amino acids were removed through absorption by active carbon. By using Sephadex G-25 gel filtration chromatography, a peptide mixture with low molecular weights between 1000 and 1300 was obtained. Finally, tests on amino acid composition and free amino acid concentration of oligopeptide solution showed that the oligopeptide had a high Fischer ratio of 34.71 and the yield of 11.59%.

Rheological and textural characteristics were studied in a set of 11 samples of yoghurt-modified mayonnaise at 15, 20, and 25°C. The rheometer Rheostress 300 was used to determine the static yield value, apparent viscosity, thixotropy, and elasticity. The sensory texture and flavour profiles were developed and determined in agreement with the respective international standards, using a group of selected and trained assessors. The yield value and apparent viscosity substantially decreased with increasing temperature, but thixotropy and sensory characteristics were not significantly affected by temperature. Linear and semilogarithmic relations were observed between the analytical parameters, but more complex relations, showing a maximum or a minimum, were found in some cases. Thixotropy was related to most of the sensory parameters, viscosity was related to spreadability, and significant relationships existed between the texture acceptability and the flavour acceptability. Rheological measurements were thus useful for a rapid prediction of the sensory properties of yoghurt-modified mayonnaises, but could not be used to replace any textural analysis.

While several validated methods have been developed for analysis of phenylurea herbicides in staple food plants, analytical procedures suitable for their quantification in minor crops such as poppy seeds are not available. For the registration of isoproturon use in this crop, the documentation of dynamics of its residues following treatment was requested. To accomplish this task, HPLC-MS/MS method was developed. Extraction of residues was realised by methanol-water mixture, Supelclean LC-18 SPE cartridges were used for purification of crude extracts. For HPLC separation of isoproturon SPE fraction Lichrospher C18 column (25 cm × 4 mm, 5 μm) was employed. For detection and quantification of target analyte, mass spectrometer with ion trap analyser operated in positive atmospheric pressure chemical ionisation (APCI) and MS/MS mode was used. Following performance parameters of method were obtained: detection limit 0.01 mg/kg, recovery 84%, and repeatability 7%.

This work compared the use of polymerase chain reaction (PCR) and the conventional CSN/ISO/10272 culture-based methods in the detection of Campylobacter species in ready-to-eat meals made from chicken meat. PCR was carried out with the primers specific to C. jejuni, C. coli, C. lari, and was modified with an internal control. The detection of campylobacters by PCR was performed on both untreated and spiked samples of real food purchased in local stores. For PCR, the detection limit was 2 CFU/g after 48 h enrichment in Park and Sanders broth. Duplex PCR proved to be highly reliable in the detection of campylobacters in different food types. Without extra spiking, samples from a global fast food chain exhibited positive amplification of the PCR product while but negative results were obtained from the cultivation of the same samples.

The colour of the laboratory prepared pasta was evaluated with respect to wheat flour types (M1 bright, M2 semi-bright, and M3 semolina), egg-ratio (0, 1, 2), and non-traditional cereals (archaic wheat species, tritordeum, spring barley, millet, lupin, buckwheat, and soya) supplements. The flour colour measurement confirmed its dependence on the wheat species milled - M3 obtained from durum wheat had a lower whiteness L* (89.6) and a higher yellowness b* (22.2) than the flour from common wheat (e.g. 93.6 and 8.1 for M1, respectively). As presumed, with the rising egg-ratio pasta yellowness increased - for M1-pasta, the calculated colour differences ∆E in pairs one-egg/eggless and two-egg/eggless were 1.1 and 4.7, respectively, while for M2- and M3-pasta ∆E values were only 0.8 and 1.5, respectively. The colour impacts of non-traditional cereals as 10% supplements differed between archaic wheat species, tritordeum, barley, and alternative cereals (millet, lupin, roasted buckwheat). In comparison to the standard, the greatest positive colour gain was brought by the lupin fortification (130% yellowness increase), while the worst appesred roasted buckwheat (10% decrease of whiteness, 210% increase of redness). At 20% non-traditional cereals supplements compared for M2- and M3-pasta, the highest positive increase of the pasta colour sensory perception was caused by corn and lupin additions in both pasta samples. The increase was slightly higher with M1-pasta (175%) than with M3-pasta (170%). In the mean of both pasta samples, yellowness L* increased from the standard pasta value 13.6 to 24.0 as measured for corn and lupin fortified pasta.

Polyphenolic compounds are widely distributed in plants and are a common part of human diet. Polyphenols are known to be potent bioactive molecules, predominantly with protective effects. Many of xenobiotics, including polyphenols, influence the activities of various enzymatic systems. Such interactions can modulate the activities of co-administered drugs. The identification of polyphenols' potential for the interactions based on metabolic changes is thus necessary. Cytochrome P450, which takes part in the metabolism of more than 90% of used drugs, is an important enzymatic system which can be influenced. We therefore determined the influence of quercetin and trans-resveratrol on the activity of cytochrome P450 1A2 in rats. A perfused rat liver model and phenacetin as a marker of 1A2 activity were used. Moreover, we studied the dependence of trans-resveratrol's activity on sex in both sexes. Trans-resveratrol did not influence the 1A2 activity, but it enhanced sexual differences in the metabolic activity. Our results also confirmed different metabolic activities between sexes. Female rats metabolised faster through 1A2. Based on our results, we suggest that quercetin is an inhibitor of cytochrome P450 1A2 isoenzyme.

Barley (Hordeum vulgare L.) and oat (Avena sativa L.) are important crop species. 1865 accessions of winter barley, 2707 accessions of spring barley and 1998 accessions of oat are maintained in RICP Gene bank. The expert core collection is used to be established as a tool for germplasm study, conservation of genetic variability and for the identification of useful genes. The main aim of this study was to evaluate genetic diversity of barley and oat genotypes within the expert core collections. Genetic variation of 176 barley accessions was analyzed using 26 microsatellite loci, covering all 6 chromosomes. 330 oat accessions were analyzed using 26 microsatellite loci that are mapped only into linkage groups. For 26 barley microsatellite loci, 328 alleles were detected. The average number of alleles per locus was 12.6. In oat, for 26 oat microsatellite loci, 353 alleles were detected. The average number of alleles per locus was 13.6. The average DI (diversity index) was 0.11 in barley and 0.09 in oat. Dendrogram and PCA (Principal Component Analysis) based on microsatellite data showed a different influence of the place of origin, age of variety and pedigree on grouping into clusters. PCA showed that the breeding process had a negative impact on the level of genetic diversity and therefore there is a necessity of barley and oat germplasm conservation.

Germination is one of the most effective ways of preparing grain legumes for consumption. Because it involves the total or partial elimination of some anti-nutritional compounds, it is also one of the simplest methods of enhancing the palatability of grain legumes, thereby increasing their consumption as a valuable source of nutrition. The main objective of this paper is to describe the changes that take place in α-galactosides during germination. During germination, galactose molecules gradually become detached from α-galactosides due to the effect of the enzyme α-D-galactosidase activated during the process. To simulate the degradation of α-galactosides during legume seed germination, we applied nine equations to the evaluation of the experimental data obtained with the germination of three types of grain legume seeds; mung bean, chickpea, and lentil.

Echinacea species are popular herbal medicine and food supplements for enhancing the immune system. This study was conducted with the aim of developing an efficient heat reflux extraction of caffeic acid derivatives from dried adventitious roots of Echinacea purpurea obtained in bioreactor cultures. Water, methanol (20, 40, 60, 80, and 100%), and ethanol (20, 40, 60, 80, and 100%) were used as solvents for the extraction of caffeic acid derivatives. Another parameter used for the optimisation was the solvent temperature during extraction. The treatment of samples with 60% ethanol at 60°C for 2 h proved to be the most suitable procedure. This treatment was also responsible for the higher yields of total phenolics, flavonoids, and polysaccharides.

Polyphenols can greatly affect the sensorial characteristics and stability of wine. The concentration of polyphenols in wines is very low, the sample must be thus concentrated before the analytical measurement. The extraction on solid phase (SPE) is a suitable method for the isolation, purification, and concentration of polyphenols from complicated matrices. RP-HPLC with diode array detection was used for the separation and identification of polyphenols. A library of absorption spectra of standards was created and used for the identification of 14 polyphenols in wines. The contents of the individual polyphenols and their changes after the addition of four tannin preparations were determined in eight white and two rosé wine samples. The influence of the flavour profile of the applied tannin preparations on sensorial characteristics of wines was established

In the present work we study the prevalence of fungal flora in the tracheal epithelium of wild birds in a rehabilitation centre. Two hundred and sixteen birds representing 26 species from seven orders were sampled. Yeasts and moulds were isolated from 92 of the birds sampled (42.5%); in 24.5% only yeasts, in 12.5% only moulds and in 5.5% both moulds and yeasts together. The cattle egret was where the greatest number of animals with positive isolation was detected. The prevalence of yeasts shows significant differences between raptors and Ciconiiformes. Within the yeast flora, basically there were strains belonging to the genus Candida, mainly C. albicans. In the moulds, almost a half of them belonged to the genus Aspergillus.

Two cultivars (Nicola and Saturna) largely distinguishing from each other in cooking behaviour and one cultivar (Agria) grown in six different cultivation regimes were tested by the CPEM (cooked potato effective mass) method for the potato sloughing assessment. The sloughing process is characterised by two cooking and disintegration stages, from which two basic CPEM parameters are derived: cooking time as the starting point of disintegration and the rate of the disintegration. Both parameters are analysed as functions of the tuber density in linear models of both stages. Significant differences in CPEM parameters and in the linear models were observed between different varieties. The data from two-year measurements were in basic agreement with our previous concept of the limited contribution of starch in the first cooking stage and of its more important role in the second disintegration stage of sloughing. The results indicated a close association between the mechanisms controlling sloughing and the tuber density in the cultivars Agria and Saturna. A different cooking behaviour was observed in the case of the typical salad cultivar Nicola with a considerably lower cooking time sensitivity to the tuber density.

Calculations of transient temperatures of food products after they are transferred from a warm environment into a display cabinet, require data on the surface heat transfer coefficient (SHTC). There is no forced air flow in an ordinary display cabinet, so the energy transfer is achieved mainly by free convection, conduction to a supporting plate, and radiation. Theoretical analysis of the heat transfer to a cylindrical sample demonstrates the relative influences of these mechanisms. This work investigates the apparent surface transfer coefficients with metal models. Heated models were placed individually (bare) in containers with and without lids. Each model was surrounded by identical containers filled with water. These were initially at the same temperature as the model or at the mean cabinet temperature. There were one, two, or three layers of these water containers. From the measured time-temperature histories of the model and the air surrounding the model, the SHTCs were calculated as functions of time and transformed into the dependencies between SHTC and temperature difference. The highest SHTCs were observed when the model was placed directly on the metal shelf of the display cabinet. The models surrounded by cool water containers showed lower SHTC values. The lowest SHTC values were found with the models placed in the middle of three layers of warm water containers. Placing the model on an insulating base leads to a lower SHTC. This effect confirms that the heat conduction through the substrate increases the heat transfer from the model and thus increases the average value of the apparent SHTC.

Patatin relative abundance in SDS-extractable protein and patatin content in dry matter were evaluated in tubers of forty processing and table potato cultivars usually cultivated in the Czech Republic, Germany, and the Netherlands. The patatin characteristics were evaluated over three experimental years. Patatin relative abundance in the processing cultivars achieved on average a significantly higher value (P < 0.001; Tukey HSD test) than patatin relative abundance in the table cultivars, resulting in average values of 25.80% and 21.59%, respectively. A high patatin relative abundance (over 30% in extractable protein) was determined only in the case of two cultivars: Vaneda (average 31.29%) and Tomensa (average 31.24%). Patatin content in tuber dry matter was significantly higher in the processing potato cultivars in all three experimental years (P < 0.001), attaining a mean of 1.28% with the processing cultivars and 1.03% with the table cultivars. The direct effect of the cultivar on patatin relative abundance in SDS-extractable protein was higher (33.1% for processing potato cultivars and 48.1% for table potato cultivars) than the effect of the growing year (15.6% for processing potato cultivar and 22.8% for table potato cultivars).

An in vitro propagation of an economic leguminous tree, Acacia chundra, has been standardized. Induction of bud sprout was obtained from shoot tip and nodal explants derived from in vitro grown plants of A. chundra on the Murashige and Skoog (MS) basal medium supplemented with 6-benzylaminopurine (BA) (1.0 mg/l) and 20 mg/l adenine sulfate (Ads). The rate of multiplication was obtained on MS medium supplemented with 1.5 mg/l BA, 0.01 to 0.05 mg/l (indole-3-acetic acid) IAA and 50 mg/l Ads. The multiplication rate varied from 3 to 6 shoots depending on the growth regulators used. Excised shoots were rooted on half-strength MS basal salts supplemented with 0.25 mg/l indole-3-butyric acid (IBA) or IAA and 20 g/l (w/v) sucrose after 10 to 12 days of culture. The micropropagated plantlets have been acclimatized and successfully transferred to soil.

β-Galactosidase is an important industrial enzyme in the hydrolysis of milk and whey lactose. The enzymatic hydrolysis of lactose allows to avoid health and environmental problems posed by this disaccharide. In addition, this enzyme catalyses the formation of galacto-oligosaccharides, which are prebiotic additives for the so-called "healthy foods". β-Galactosidase is one of the relatively few enzymes that have been used in large-scale processes in both free and immobilised forms. This article presents a review of recent trends in immobilisation of β-galactosidase and their application in food industry.

Buckwheat is introduced into the diet as an alternative crop of renewed interest due to its nutritive and health-promoting value. Experiments with animal models have demonstrated that buckwheat flour may alleviate diabetes, obesity, hypertension, and hypercholesterolemia. A number of nutraceutical compounds exist in buckwheat grains and other tissues. These are a rich source of starch, proteins, antioxidants, and dietary fibre as well as trace elements. The biological value (BV) of buckwheat proteins is comparable to BV of other protein sources. Besides high-quality proteins, buckwheat grains contain some components with prophylactic value: flavonoids, fagopyrins, or thiamin-binding proteins. For the food industry, buckwheat grains are a valuable raw material to be used for the production of functional foods. Buckwheat flour may be a valuable and important ingredient in diets or food products, taking into consideration its nutritive value and potential promotion of human health.Keywords:

An investigation was conducted to find out the effects of two triazole fungicides (triadimefon (TDM) and hexaconazole (HEX) - 15 and 10 mg/l per plant, respectively) on the biochemical constituents and tuber quality of white yam (Dioscorea rotundata Poir.). The exposure of white yam plants to the fungicides showd increased chlorophyll, carotenoids, xanthophylls, and anthocyanin contents and altered the membrane integrity in terms of electrolytic leakage and lipid peroxidation. The triazole treatments enhanced the accumulation of proline and total phenols in tubers. The visible symptoms of fungicides appeared as thickening and darkening of leaves. Both the triazoles increased the antioxidants (ascorbic acid, reduced glutathione, and tocopherol) contents. The data suggests that, apart from their fungicidal properties, the application of triazole fungicides may be a useful tool to increase the tuber quality in yam plants.

The main aim of the article is to understand the influence of factors biasing purchase decisions connected with measurement of consumers' involvement. Consumption expenditures are purposefully subdivided according to the classification made by the Statistical Office of the European Communities. The performed survey showed that the most important factors biasing purchases of all commodity groups are products' characteristics and the perceived quality. Together with these goes the factor price, nevertheless for example for the commodity group health price did not appear in the scale of the perceived importance at all. Factor necessity of need proved to be significant for decision making about the purchase of all commodities with the exception of alcoholic drinks and tobacco and recreation. Former experience compared to that is not crucial for clothing and footwear and housing equipment and contents. For alcoholic drinks and tobacco, there has notably approved also the factor brand. These analyses enable disclosure of rules of consumer decision making and thereby definition which factors for individual commodities should be targeted by the help of the marketing doyens or where the gradual changes should be achieved.

There exists no energy policy in the European Union, but rather a whole series of long-term goals setting its strategic orientation. Until 2000, when the Green Book named "Towards the European Strategy of Energy Supplies Securing" was accepted, no real debate on the strategy of energy was held in the EU. The Green Book represents a key document of the European energy policy and it originated as a consequence of the fears of the European Committee regarding the growing energy dependence on the energy resources imports, from the politically not stable parts of the world. Among the three key points of the energy strategy, there belong stable supply of energy, acceptable energy prices and environment protection. With regard to the deepening European integration and interconnection of the individual member states economies, the decisions of one country also have an energy impact on the other states. Therefore, the cooperation among the individual members is necessary.

Urbanization has drastically changed soil properties, and an assessment of these changes is essential for soil management and soil health. The activities of urease, acid phosphatase, invertase and catalase, soil organic matter, pH, electrical conductivity (EC) and clay (< 0.01 mm) content of urban soils under two land-uses in the central built-up area of the Shenzhen city were investigated, and multivariate analysis was used to study the relationship between soil enzymes and soil physical-chemical properties. The results showed that invertase activity in roadside soil was significantly higher than that in urban park soil, whereas catalase activity was significantly higher in urban park soil. Soil organic matter had significant positive correlation with activities of invertase, urease and acid phosphatase but not with catalase. Soil pH had a significant negative direct effect on urease and acid phosphatase activity, but the effect was counteracted by positive indirect effect of soil organic matter. Soil EC had a positive direct effect on activities of catalase and there was a significant correlation between soil EC and soil catalase activities. Soil organic matter, soil pH and EC were the major factors influencing activities of soil enzymes.

Plant root and shoot dry weight, leaf relative water content (LRWC) and chlorophyll content were reduced by 30%, 21%, 15%, 34%, respectively, at 40mM NaCl as compared to non-salt stress conditions. However, membrane permeability (MP) of plant increased (85.0%) with increasing salinity. Foliar nutrient application (FNA) alleviated deleterious effects of salinity stress on growth and this effect was statistically significant. The highest alleviation effect of FNA at 40mM salinity stress was observed in the case of 10mM foliar KNO₃ and Ca(NO₃)₂ application, resulting in increase in plant root dry weight (50%), shoot dry weight (50%), LRWC (8.2%) and MP decrease (27.4%) at 40mM NaCl. Phosphorus, Fe and Zn contents in shoots and roots of plants also increased with FNA treatments, but they were still much lower than those of non-salt stress treatment. Sulphur, P, Fe and Zn contents of shoots reached similar values as in non-salt stress treatment when KNO₃ was applied, whereas Fe, Mn, Zn, and Cu contents of roots reached the values of non-salt stress treatment when Ca(NO₃)₂ was applied.

An incubation experiment with addition of EDTA and alfalfa into soils contaminated with heavy metal over 200 years was carried out in order to evaluate the EDTA effects on microbial properties. Alfalfa was added to soils together with EDTA to examine its abilities to improve microbial activities affected by EDTA. The obtained results showed that the addition of EDTA led to a significant decrease of microbial biomass C during the first 24 days of incubation. At the end of the experiment the microbial biomass C significantly increased quite close to the original level. The EDTA amendment caused, probably due to the toxic effects, a significant increase in respiratory activities and of the metabolic quotient qCO₂. An addition of alfalfa significantly improved the microbial biomass C contents in arable soils treated together with EDTA. Both, respiratory activities and qCO₂ significantly increased after the soil treatment with EDTA together with alfalfa. EDTA alone decreased the microbial biomass, alfalfa alone as organic substrate was mineralised and utilised by soil microorganisms for their metabolism.

The growth and survival of rudd Scardinius erythrophthalmus (L.) were evaluated in a laboratory at 25°C. In 20-day Experiment 1, first-feeding larvae at the age of 4 days post-hatch (initially: TL = 5.7 mm, BW = 0.9 mg) were fed live Artemia nauplii or commercial dry feed (Aller Futura Larvae, AFL) or combinations of both. Even the longest period of initial feeding of nauplii (6 days) was insufficient to obtain satisfactory larval growth after weaning to AFL (TL = 12.4 mm and BW = 17.7 mg vs. TL = 18.9 mm and BW = 68.5 mg for the nauplii-fed fish, significant differences). Nauplii-fed older larvae (24 days post-hatch) were then used in Experiment 2, in which they were fed AFL or Ewos AgloNorse (EAN) dry feeds for 40 days. The EAN diet proved to be significantly (P ≤ 0.05) superior to AFL regarding the final fish growth (TL = 36.5 mm and BW = 506.8 mg vs. TL = 33.4 mm and BW = 392.0 mg ), final survival rates (97.6% vs. 100%) and the incidence of spinal deformities (0% vs. 13.5%).

The paper presents the results of the research focused on crisis management, which is based on the process of change management by the author-formulated methodology of the creation, implementation and changes of business strategies and requirements for their improvement due to the incidence of a turbulent management environment and other essential factors. The main factors of crisis and methods of their analysis are formulated. Thereinafter, the strategies of solving crisis situations are formulated. The company Bioveta, Inc. is analysed in detail. The research has proved that companies with modern management need a well-made and working system of crisis management due to their complexity and risks.

Proteolysis is the principal and most complex biochemical event occurring during the maturation of the majority of ripened cheese varieties. In addition to softening the cheese body, proteolysis influences the development of cheese flavour via the formation of amino acid and peptides which make a direct contribution to flavour. Goat, cow and sheep cheeses have been elaborated with raw milk and calf rennet. The extent of proteolysis was monitored over six months of ripening and means of HPLC peptide profile analysis. The influence of season on the changes in hydrophobic and hydrophilic peptides and the HO/HI ratio during the ripening of the cheeses were studied.

3-alkyl-2-methoxypyrazines (MPs) represent an important and potent class of odor-active compounds associated with wine quality. 30 ng/l each of 3-isobutyl-2-methoxypyrazine, 3-isopropyl-2-methoxypyrazine and 3-secbutyl-2-methoxypyrazine were added to a Riesling and Cabernet Franc wine and monitored with HS-SPME-GC-MS over 18 months to investigate the effects of various closure and packaging options as well as light and storage temperature on MPs. Other impact odorants were monitored using SPE-GC-FID. Changes in MP concentrations during bottle aging varied with closure/packaging option, with the greatest decrease evident in Tetrapak® cartons. We observed similar changes in other impact odorants to previous studies, with synthetic corks displaying an increased capacity for sorption compared to natural corks and screwcaps. MPs did not vary consistently over time with light or temperature conditions. Acetate esters decreased, regardless of light or temperature conditions, while phenethyl acetate and isoamyl acetate decreased at a greater rate in ambient temperature conditions compared with 12°C. Free and bound SO₂ retention was higher in light-excluded conditions and influenced by bottle hue.

In this paper we have discussed the problem of decomposition of a response variable into other predictor variables whose product gives the value of the response variable. This methodology is known as multiplicative yield component analysis. We have discussed the applications of multiplicative yield component analysis in cereal science and breeding. The discussion of multiplicative yield component analysis involves the description of yield component analysis for cereal grain yield, single genotype yield component analysis and across-genotype yield component analysis.

Changes in root anatomical structures at successive cycles of selection (cycle 1 to cycle 18, alternating) were observed in the study of maize (Zea mays L. cv. Saracura-BRS 4154) capable to survive and produce in temporarily flooded soils; this cultivars was developed by the Maize and Sorghum National Research Center through stratified phenotypic recurrent selection for cultivation wetland soils. Field trial was carried out and flooding of the soil was initiated at the six-leaf stage; the soil was flooded with water (20-cm deep) three times per week. Root sample was collected, fixed, and selected for observation in photon microscope. A gradual increase in the number of aerenchyma, the proportion of vascular cylinder, smaller metaxylem, and phloem and epidermis width, and a decrease in exodermis and cortex were observed in successive selection cycles. Such phenotypic changes impart the flood tolerance ability to this maize cultivar.