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Oriental beech (Fagus orientalis) is one of the main tree species in Turkey. In this study, 3-year storage of oriental beechnuts from eight Turkish provenances was researched. Beechnuts were stored at −6°C in sealed containers. The average germination percentages of over all provenances were 91.67, 75.92, and 76.75%, prior to initial storage, after 1 year in storage, and after 3 years in storage, respectively. There were significant decreases in the germination percentages of seven provenances while one provenance retained its high initial germination ability over a 3-year storage period. The loss of viability initiated from the radicle and the plumula in stored beechnuts. The average mean germination times were 10.43, 10.22, and 11.89 weeks prior to storage, after 1 year in storage, and after 3 years in storage, respectively. The beechnuts stored for 3 years germinated significantly later than both fresh beechnuts and beechnuts stored for 1 year in terms of average mean germination time. This study showed that oriental beechnuts can be stored in a dormant state for at least 3 years at low temperature (−6°C) with a low moisture content (about 6–7%).  相似文献   
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Studies on differential response of wheat cultivars to boron toxicity   总被引:1,自引:0,他引:1  
Experiments were carried out to study the differential responses of different wheat cultivars to boron toxicity in field, greenhouse and growth chamber conditions. In field trials carried out at two locations, both of which are known to contain toxic amounts of water-extractable B, significant correlations were obtained between toxicity symptoms and grain yields. The only durum cultivar included in this group of experiments (Kunduru 1149) was the most sensitive of the 21 cultivars trialed. The most tolerant cultivars were of local origin. Genotype-environment interaction was considerably large. Twenty-nine bread wheat and three durum wheat cultivars were compared in a greenhouse experiment with and without the application of 40 mg L-1 B. Again, the durums were the most sensitive cultivars. The most tolerant cultivars were either selections from local populations or had at least one parent of local origin. The detrimental effect of B on root dry matter production was much higher than on shoot dry matter (45 and 26%, respectively), but genotypical variation was greater in shoot growth retardation. While this implies the possible role of reduced translocation, high concentrations of B in the shoots of tolerant cultivars (though lower than in the sensitive cultivars) indicated the existence of other contributing mechanisms, such as tissue tolerance. Also, greater genotypical variation in older leaves showed that reduced uptake might be more important than reduced translocation in some cases. Due to the lack of correlation between results from the field and the controlled-environment studies, it was concluded that screenings should be undertaken in both situations as a means of verification. Another conclusion drawn was that symptom scoring for B tolerance was more reliable than measuring plant B concentrations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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The aim of this study was to determine the effects of the body condition score (BCS) of ewes before and during the mating season on their reproductive performance under an extensive production system. In this study, 240 Kivircik sheep from the flocks of two breeders were used for over a 2-year period. The flocks were fed under extensive conditions on natural pastures throughout the year. The ewes were synchronized in two different periods, one of which was 45 days before the other. Before the introduction of rams to the ewes, the ewes were weighed after measuring their BCS. Detailed records were kept for every flock in each year. We found significant effects of BCS on pregnancy rate, lambing rate (P < 0.05) and fecundity (P < 0.05). The BCS for the highest pregnancy, lambing rate, and fecundity was determined between 2.01 and 3.00, while the lowest rates for these traits were ≤1.50. The highest rates of the pregnancy rate, lambing rate, and fecundity and gestation productivity were 75.9%, 70.9%, 1.11 and 3.34 kg, respectively.  相似文献   
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Tei index (myocardial performance) and cardiac biomarkers were evaluated in dogs with parvoviral enteritis (PVE). Tei index was calculated as isovolumic contraction time plus isovolumic relaxation time divided by ejection time. Myocardial and skeletal muscle damages were assessed by serum levels of cardiac troponin I (cTnI), creatine (phospho) kinase, lactate dehydrogenase and aspartate aminotransferase. Serum magnesium level was also determined. According to treatment response, dogs were divided into the survivor (n=20) and non-survivor groups (n=23). Seven healthy dogs served as controls. The mean value of the Tei index was higher in non-survivors, compared with survivors (p<0.02) and healthy controls (p<0.01). Serum level of cTnI in non-survivors was higher than that of survivors and controls (p<0.05). Tei index showed the highest sensitivity and specificity to predict mortality. The findings of an elevated Tei index and an increase in serum cTnI are factors associated with a poor prognosis in cases of canine parvovirosis.  相似文献   
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An attempt has been made to set up a relationship between the removal efficiency and the dispersion characteristics of biological filters. For granular-media trickling filters, effluent concentrations have been calculated with the equation of complete mixing at low flow rates and by means of a dispersed plug-flow model for large hydraulic loadings. For coarse media, the mixed flow zone disappears and the substrate removal is obtained using the equation of dispersed plug flow. The effect of temperature and substrate concentration on the filter efficiency has been investigated using the model developed and the application of this theory to the practical problems has been thus demonstrated.  相似文献   
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