The study was conducted to investigate the effect of salinity of irrigation water on seeds quality and seedling growth characters for three oat cultivars (Shifaa, Hamel and Pimula) . It was carried oat in seed technology laboratory, field crops department, College of Agriculture, Baghdad University of Aljadiriya for period of tow years. Seeds of three oat cultivars (Shifaa, Hamel and Pimula) taken from a field experiment conducted during 2014-2015 and 2015-2016 irrigated with three salinity water levels (3, 6 and 9 dS.m-1 ) in addition to river water with salinity level of 1.164 dS.m-1 as control. Seeds were tested in laboratory experiments to estimate their quality, and completely randomized design with three replicates was used. Statistical analysis results for both seasons showed a significant effect of salinity stress with increasing salinity concentration in all studied traits, where mean values of studied traits decreased significantly at salinity level of 6 dS.m-1 and the effect of salinity level (9 dS.m-1 ) recorded the lowest means of germination percentage (71.4% and 71.1%), germination speed (3.57 and 3.49 seedling.day-1 ), radicle length (5.12 and 7.19 cm), plumule length (7.87 and 11.7 cm), radicle dry weight (2.91 and 2.55 mg), plumule dry weight (8.92 and 9.02 mg) and seedling vigor (838 and 820 mg) for both seasons, respectively. No significant differences recorded between water salinity level of 3 dS.m-1 and river water in all studied traits. Cultivars Shifaa and Pimula were superior in traits of radicle and plumule length, whereas cultivar Hamel was superior in traits of radicle dry weight (8.50 and 9.34 mg), plumule dry weight (17.38 and 17.68 mg) and seedling vigor (2287 and 2305 mg) for both seasons, respectively. So it is concluded that the effect of salinity stress is not restricted on plant growth and yield only, because it also affects the quality of produced seeds. Consequently, we recommend using irrigation water with salinity level of less than 6 dS.m-1 for seeds production.
Purpose: The purpose of this study was to clarify the basic dimensions, which seeks to indestructible scenarios practices within the organization, as a final result from the use of this philosophy.
Methodology: The methodology that focuses adoption researchers to study survey of major literature that dealt with this subject in order to provide a conceptual theoretical conception of scenarios theory .
The most prominent findings: The only successful formulation of scenarios, when you reach the decision-maker's mind wa takes aim to form a correct mental models, which appear in the expansion of Perception managers, and adopted as the basis of the decisions taken. The strength l
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In this paper, the reliability of the stress-strength model is derived for probability P(Y<X) of a component having its strength X exposed to one independent stress Y, when X and Y are following Gompertz Fréchet distribution with unknown shape parameters and known parameters . Different methods were used to estimate reliability R and Gompertz Fréchet distribution parameters, which are maximum likelihood, least square, weighted least square, regression, and ranked set sampling. Also, a comparison of these estimators was made by a simulation study based on mean square error (MSE) criteria. The comparison confirms that the performance of the maximum likelihood estimator is better than that of the other estimators.
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In this paper, estimation of system reliability of the multi-components in stress-strength model R(s,k) is considered, when the stress and strength are independent random variables and follows the Exponentiated Weibull Distribution (EWD) with known first shape parameter θ and, the second shape parameter α is unknown using different estimation methods. Comparisons among the proposed estimators through Monte Carlo simulation technique were made depend on mean squared error (MSE) criteria
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