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1.
Summary The objective was to study the genetic basis of bolting and stem length in sugar beet full-sibs, developed by a factorial mating design (N.C. design II). The extent to which the inheritance of these characters can be attributed to the additive and non-dominance variation was investigated. The genetic analysis consisted of three sets (4×10, 4×8, and 3×8) of progenies. Estimates of additive genetic variance (2 A) and variance due to dominance deviations with some fractions of epistatic variance (2 D) were obtained for both characters. Bolting had a relatively large proportion of total genetic variance accounted for by 2 A. In most cases, non-additive effects were also important in determining the type of gene action in bolting. Stem length showed similar genetic variation to bolting susceptibility. Bolting resistance seemed to be dominant to the bolting susceptibility in most cases. Narrow sense heritability estimated for bolting was generally very large (0.93 to 0.96), which suggests that early generation selection for bolting resistance in a sugar beet population would be successful.  相似文献   
2.
Influence of Ethrel upon morphology and sugar content of sugar beet Repeated spraying of growing sugar beet plants with 100 and 200 ppm solutions of Ethrel changed the shape of the storage roots and reduced their sugar content. When CCC was added to the Ethrel solutions, the negative influence of Ethrel upon the sugar content was nearly abolished.  相似文献   
3.
Influence of Ancymidol and Ethrel on the synthesis of gibberellic acid (GA3) in cereal plants. In pot experiments with oat, barley and rye both growth regulators Ancymidol and Ethrel considerably reduced the GA3 content in the 3 plant species. Ancymidol was approximately 10 times more effective than Ethrel. This higher effectivity of Ancymidol on the GA3 content and the different structure of the Ancymidol molecule compared to Ethrel makes it probable that Ancymidol inhibits the GA synthesis in a different way than Ethrel (or CCC). Although Ethrel was less effective in reducing the GA content it decreased the stalk length more than Ancymidol. It is concluded that Ethrel not only influences the GA induced growth but also other processes which regulate the length growth of plants.  相似文献   
4.
Plant Foods for Human Nutrition - Findings regarding the association between tea and coffee consumption and oxalate-calcium stone are sparse and uncertain. The purpose of this study was to...  相似文献   
5.
Eurasian Soil Science - Experiments were conducted for thirty representative surface and subsurface soils collected from different physiographic units and moisture regimes in southern Iran to...  相似文献   
6.
Background: Selective phosphodiesterase (PDE3) inhibitors improve cardiac contractility and may use in congestive heart failure. However, their proarrhythmic potential is the most important side effect. Methods: In this research, we evaluated the potential cardiotonic activity of six new synthesized selective PDE3 inhibitors (6-hydroxy-4-methylquinolin-2(1H)-one derivatives) using the spontaneously beating atria model. In each experiment, atrium of reserpine-treated rat was isolated and the contractile and chronotropic effects of a synthesized compound were assessed. The 3-isobutyl-1-methylxanthine, a non-selective PDE inhibitor, was used for comparison. Results: The results showed that, among new compounds, the best pharmacological profile was obtained with the compound 6-[4-(4-methylpiperazine-1-yl)-4-oxobutoxy]-4-methylquinolin-2(1H)-one, C6, which displayed selectivity for increasing the force of contraction (168 +/- 5% change over the control) rather than the frequency rate (138 +/- 5% change over the control) at 300 muM. However, C6 at concentrations of 10 and 100 muM produced left and upward shift in the positive inotropic concentration-response curve of isoprenaline. The -log EC50 of isoprenaline was 8.843 +/- 0.171 in the absence, 9.448 +/- 0.138 and 9.456 +/- 0.107 in the presence of 10, 100 muM of C6, respectively (P<0.001, n = 6). Also, amrinone, a selective PDE3 inhibitor, shifted the isoprenaline concentration-response curve to the left and upward. The concentration of 10 and 100 muM amrinone decreased -log EC50 of isoprenaline to 9.527 +/- 0.287 and 9.423 +/- 0.243, respectively (P<0.001, n = 6). Moreover, the positive chronotropic effect of isoprenaline was not affected by amrinone or C6. Conclusion: This study provides functional evidence for the positive inotropic effect of C6. Considering the augmentation of isoprenaline positive inotropic concentration-response with C6 and amrinone, we conclude that C6 produces its effect via potentiation of cAMP-dependent signaling system and possibly by inhibition of PDE3 activity.  相似文献   
7.
Background:Hereditary spherocytosis and hereditary dRTA are associated with mutations in the SLC4A1 gene encoding the AE1. In this study, some patients with clinical evidence of congenital HS and renal symptoms were investigated. Methods:Twelve patients with congenital HS and renal symptoms were recruited from Ali-Asghar Children’s Hospital (Tehran, Iran). A patient suspected of having dRTA was examined using WES method, followed by Sanger sequencing. Results:One patient (HS03) showed severe failure to thrive, short stature, frequent urinary infection, and weakness. A homozygote (rs571376371 for c.2494C>T; p.Arg832Cys) and a heterozygote (rs377051298 for c.466C>T; p.Arg156Trp) missense variant were identified in the SLC4A1 and SPTA1 genes, respectively. The compound heterozygous mutations manifested as idRTA and severe HS in patient HS03. Conclusion:Our observations, for the first time, revealed clinical and genetic characteristics of idRTA and severe HS in an Iranian patient HS03. Key Words: Erythrocyte membrane protein, Hereditary spherocytosis, Hemolytic anemia, Whole-exome sequencing  相似文献   
8.
We developed a three-step classification approach for forest road extraction utilizing LiDAR data. The first step employed the IDW method to interpolate LiDAR point data (first and last pulses) to achieve DSM, DTM and DNTM layers (at 1 m resolution). For this interpolation RMSE was 0.19 m. In the second step, the Support Vector Machine (SVM) was employed to classify the LiDAR data into two classes, road and non-road. For this classification, SVM indicated the merged distance layer with intensity data and yielded better identification of the road position. Assessments of the obtained results showed 63% correctness, 75% completeness and 52% quality of classification. In the next step, road edges were defined in the LiDAR-extracted layers, enabling accu- rate digitizing of the centerline location. More than 95% of the Li- DAR-derived road was digitized within 1.3 m to the field surveyed nor- rnal. The proposed approach can provide thorough and accurate road inventory data to support forest management.  相似文献   
9.
The induction of bolting after different periods of vernalization was studied in the parental, F1, F2 and backcross generations (F2× P1 and F2× P2) of three crosses between five sugar beet lines. The parental lines represented different levels of bolting resistance. The populations were evaluated in replicated field or greenhouse trials. Generation mean analysis was used to quantify the genetic effects of bolting. The additive (d) parameter was predominant for those levels of cold treatment that stimulated the bolting to occur. The dominance (h) parameter was also shown to be important in most cases. In one cross, the additive × additive (i) type of epistasis was significant. The chances of detecting genetic effects are increased by exposing the plants to vernalization conditions which maximize the difference between two parental lines of each cross. Hence, it would be sensible to exploit both additive and non-additive genetic effects in any selection programme.  相似文献   
10.
Sugar beet progeny lines screened for both high water use efficiency and high sugar yield under drought stress conditions in the field were assessed for the rate of seed germination and early seedling growth in water deficit stress, induced by mannitol solutions. Seeds of nine different sugar beet progeny lines were grown in three experimental conditions using filter paper, perlite and water agar as substrate. Three levels of 0.0, 0.2 and 0.3 m mannitol concentrations were applied in each experiment. A factorial design was used with three replications. Germination percentage was determined in all experiments. Seedling growth parameters such as cotyledon fresh weight, cotyledon dry weight, root fresh weight, root dry weight (RDW) and root length (RL) were measured experimentally. Abnormality was only recorded in the filter paper experiment. The results showed that drought stress could be simulated by mannitol solution and significant differences were found between stress levels for seedling characteristics. Distinct genetic variances were found among progeny lines with respect to germination and early seedling growth characteristics, except for cotyledons and RDW. Seedling growth and germination rates severely declined at the highest concentration of mannitol. The rate of abnormality was increased progressively at the germination stage with an increase in mannitol concentration but it was more pronounced in the drought‐susceptible progeny lines. The highest values of relative germination % and relative growth % of RL were obtained for the most tolerant line. In conclusion, seedling characteristics, in addition to other physiological components involved in the seed germination process under specific stress conditions, may be considered for breeding purposes.  相似文献   
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