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The number of stomata and the concentration of macro- and microelements in four new winter wheat genotypes: Lenta, Lara, Perla and Fiesta were investigated in two localities in Croatia in the 1997/98 growing season. The stomata number per mm2 was determined by a standard method. N was established by the micro-Kjeldahl method, P spectrophotometrically and K, Ca, Mg, Zn, Cu, Fe and Mn by the AAS method. The interrelation of the investigated parameters was determined by multiple regression and correlation analysis. The results obtained indicate that the number of stomata per mm2 and the macro- and microelement concentrations depended on the genotype, the phenophase and the locality. A statistically significant correlation was found between the stomata number per mm2 and the macro- (N, P, K, Ca, Mg) and microelement (Zn, Cu, Fe, Mn) concentrations.

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C. Hansch and A. Leo , Substituent Constants for Correlation Analysis in Chemistry and Biology, Wiley, New York, 1979. Leo A. Substituent

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, A Leo , Substituent Constants For Correlation Analysis in Chemistry and Biology, John Wiley & Sons, New York, 1979. Leo A. Substituent Constants For

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Genetic variability and correlation analysis were studied in 20 accessions of ‘egusi’ melon during two growing seasons. The genotypic correlation coefficients with seed yield were partitioned into direct and indirect effect causes. Heritability in the broad sense ranged from 17% for fruit circumference to 90% for days to germination and flowering in the early season, while in the late season, heritability ranged from 7% for seed weight per fruit to 88% for days to germination. High phenotypic and genotypic coefficients of variation were recorded for seed yield while days to maturity had the lowest in both seasons. Fruit circumference and fruit weight had significant genotypic and phenotypic correlation with seed yield in the early season, while number of branches per plant, vine length per plant, number of fruits per plant and fruit circumference per plant showed significant genotypic and phenotypic correlation with seed yield in the late season. Environmental correlation coefficients were significant between seed yield and vine length per plant, number of fruits per plant and fruit size per plant. Vine length per plant and fruit circumference per plant had the largest positive direct effect on seed yield. Knowledge of the relationship of these characters with seed yield will aid in the selection of genotypes that have high seed yield, which will also be specific to the two major seasons in the year.

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The fertilizer response of oilseed rape (Brassica napus var. oleifera f. biennis L.) was investigated on the chernozem soil in Eastern Hungary in a three-year experiment with two sowing times. The results proved that oilseed rape had high fertilizer (N+PK) demand. In the experiments, N = 210 kg ha−1 +PK proved to be the optimal fertilizer dose. The yield-increasing effect of fertilization was 800 to 1300 kg ha−1, depending on the year. The maximum yield (5000 kg ha−1) was obtained in the year with least infection. The excellent natural nutrient-providing ability of chernozem soil was confirmed by the high yield level (3000–4200 kg ha−1) of the control treatment (N = 0 kg ha−1 +PK). The results showed that the specific fertilizer utilization efficiency of oilseed rape decreased if the dose of N+PK fertilizer was increased (being 19–27 kg/1 kg NPK in the control treatment and 11–12 kg/1 kg NPK in the N = 210 kg ha−1 +PK treatment). On the other hand, fertilization improved the water utilization from 4–8 kg/1 mm precipitation + irrigation water to 11–14 kg/1 mm precipitation + irrigation water. The results of these studies confirmed that hybrid rape had excellent adaptability to the sowing time. The results of Pearson’s correlation analysis showed a strong correlation (0.6*–0.9**) between the spring precipitation and temperature and the most important diseases (Sclerotinia, Alternaria, Peronospora, Phoma) attacking oilseed rape.

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The aims of this study were to detect physiological changes in blood biochemical parameters throughout gestation, to compare the findings in nonpregnant and pregnant Lipizzaner mares in early-mid and late pregnancy, and to provide reference values for clinical chemistry parameters in this horse breed. A total of 136 venous blood samples were collected from 20 pregnant and 10 nonpregnant (control) asymptomatic Lipizzaner broodmares for biochemical analyses. Twelve parameters (albumin, total protein, urea, triglycerides, glucose, creatinine, alkaline phosphatase, aspartate transaminase, glutamate dehydrogenase, gammaglutamyltransferase, creatine kinase and lactate dehydrogenase) were measured. For the statistical analyses, correlation, analysis of variance and Kruskal–Wallis H-test were used to evaluate the possible associations between parameters. Serum triglyceride levels proved to be significantly different in pregnant mares compared to the control group. Total protein and urea levels significantly decreased, while glucose, triglyceride and glutamate dehydrogenase values increased from approx. the fifth month of gestation until parturition. Four biochemical parameters (albumin, aspartate transaminase, total protein and urea) were lower and three other variables (glucose, alkaline phosphatase and creatinine) were significantly higher in late-term pregnant mares than in mares in early or mid-gestation. It is concluded that reference values not only reflect the species, breed and sex but also the reproductive status of animals.

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Wheat is the second most important field crop on arable lands in Hungary and Croatia. Yield variations between years are high in both countries. In the short term these variations are mainly the result of the weather parameters specific to individual growing seasons. The aim of this study was to compare variations in winter wheat yields over years in four counties in Hungary and five in Croatia, with the emphasis on the impact of rainfall and mean air temperature regimes. The results showed that rainfall in spring was most decisive for winter wheat yields. The highest winter wheat yields were obtained when the rainfall in the winter half-year ranged from 230–260 mm and the spring rainfall from 180–230 mm. The precipitation in the growing season is much higher in eastern Croatia than in eastern Hungary, so water shortage is a more pronounced environmental problem for wheat in Hungary. This is probably why wheat yields were lower in eastern Hungary than in eastern Croatia in the period tested. Pearson correlation analysis on the yields and meteorological data between 1990 and 2009 revealed a positive correlation between spring rainfall and the yield, and a negative correlation between spring temperature and the yield. The results proved that yields were determined not only by weather conditions, but by many other factors (crop rotation, tillage, fertilization, variety, crop protection, etc.).

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Quality of wheat grain is a complex trait that depends mostly on the quantity and quality of protein and unified interactions between high molecular glutenin, gliadin, low molecular glutenins and abiotic stresses. The objective of this study was to evaluate the effects of genotype, environment and genotype × environment interaction on quality and some agronomic traits in wheat. Twenty divergent genotypes of winter wheat, per five from Serbia, Russia, France and Hungary were analysed in this paper. Variability was observed for quality (grain protein content and sedimentation) and agronomic traits (thousand-grain weight and test weight) in three growing seasons (2007/08, 2008/09 and 2009/10). Genotypes were statistically analysed [basic statistical parameters, AMMI biplot for the content of protein, correlation and Principal Component Analysis (PCA)] in order to assess the impact of different growing seasons on selected cultivars. AMMI analysis determined that 2008/09 was very significant for most of the genotypes. The Hungarian cultivar GK-Zugoly had the highest grain protein content (14.4%). Correlation analysis showed different relationships between the traits. PCA indicated that the total variation reflected the first two components represented with 80%, but the first principal component was more important. Results of this paper indicate that the varieties MV-Csardas and Pamyati Kalinenko can be used as a good source of genetic material for future breeding program for agro-ecological conditions of Vojvodina.

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The yield potential of wheat depends not only on genetic × environmental interactions, but also on various agronomic factors such as sowing date or the seed rate used for sowing. The main aim of this work was to determine possible correlations between the effects of different sowing dates and plant densities on the yield components of a collection of 48 wheat genotypes. Two-way analysis of variance on the data revealed that both sowing date and plant density, as main components, only had a minor effect on the yield component patterns. Correlation analysis, however, indicated that the sowing date had a greater effect on the yield components, while plant density was in closer correlation with the heading time (r = 0.90). The patterns determined for individual yield components at two different sowing dates and plant densities showed significant differences for spike length, spike fertility, grain number in the main spike, number of productive tillers, grain number on side tillers, mean grain number and grain weight. Genotypes that carry the winter (recessive) alleles of genes regulating vernalisation processes (VRN-A1, VRN-B1, VRN-D1) and the sensitive (recessive) alleles of the two genes responsible for photoperiod sensitivity (PPD-B1, PPD-D1) may have better tillering and consequently higher grain yield, though this may depend greatly on the year.

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The aspiration of this research paper is to investigate the impact of international gold prices on the equity returns of Karachi Stock Index (KSE100 index) of Pakistan Stock Exchange. The daily observations from January 1, 2000 – June 30, 2016 have been divided into three sub-periods along with the full sample period on the basis of structural breaks. Descriptive analysis used to calculate the average returns, which showed significant returns of KSE100 for the full sample, the first and the third sample periods as compared to gold returns. Standard deviation depicted the higher volatility in all the sample periods. Correlation analysis has shown an inverse relationship amid equity returns and gold returns, whereas, Philips-Perron and Augmented Dickey-Fuller tests have been employed, and time series data became stationary after taking the first difference. Johansen cointegration results have shown that the series are cointegrated in the full-sample and the first sample periods. Thus, this has demonstrated the long run association amid equity returns and gold returns in the first sub-sample and the full-sample periods. However, the second and the third sub-sample periods do not exhibit long-term association amid equity returns of KSE100 and gold returns. The outcomes of Granger causality approach identified bidirectional causation amid equity returns and gold returns in the full sample period in lag 2, and unidirectional causality has been observed from gold prices to stock prices in the full sample and the first sub-sample periods in lag 1 and lag 2 respectively.

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