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51.
52.
Plant growth regulators play a vital role in fruit growth and development. However, effects of compounds belonging to the group of brassinosteroids have not been fully investigated in sweet cherries. One relatively new and one commonly applied growth regulator, 22S, 23S-Homobrassinolide and GA3, respectively, were tested on ‘Summit’ and ‘Regina’ sweet cherries to determine the effects on fruit quality and physiological disorders. The substances were applied with a handgun sprayer at full bloom and at the beginning of fruit development (shuck split) for a 2-year period. GA3 was applied at the concentrations of 25, 50, 100 mgL?1 and 22S, 23S-Homobrassinolide at 0.05, 0.1, 0.5 mgL?1. A combined application of 100 mgL?1 GA3 + 0.1 mgL?1 22S, 23S-Homobrassinolide was also applied. Effects of GA3 and 22S, 23S-Homobrassinolide on fruit weight and size were evident for the concentrations applied and between the seasons for both of the cultivars. Combination of the both growth regulators and 100 mgL?1 GA3 alone produced longer fruits compared to the control trees in ‘Regina’. The 22S, 23S-Homobrassinolide applications increased the firmness of the flesh slightly, but not to a great degree, compared to the GA3 applications alone. The brightness of the red color was better with GA3 applications in ‘Summit’ and ‘Regina’. Brassinosteroid caused the fruits to have comparably dull red color. Total soluble solid contents of the cultivars were influenced by the substances and the year of the application. Stem resistance to separation from the fruit was under the influence of both treatments and seasons. In general, 22S, 23S-Homobrassinolide provided better stem resistance than the GA3 applications. There were no effects of the substances on the development of physiological disorders.  相似文献   
53.
ABSTRACT

Evaluation of pollen viability and its germination capacity are essential criteria for pollinator’s characterization. Hormones have been used to increase yield and quality of pomegranates without any reference to effects on pollen viability or germination. With this point of view, effects of field-applied 22S, 23S-homobrassinolide (HBR) after bud break at concentrations of 0.001, 0.01, and 0.1 mg L?1 were evaluated on pollen quality of Mayho?-8 pomegranate cultivar. After collection of the flowers of both sexual morphs (bisexual and functionally male), colorimetric test of 2,3,5-triphenyl tetrazolium chloride (1%) were used to estimate pollen viability. Later, pollen germination was determined in vitro on a medium containing 1% agar and 20% sucrose. Results showed that pollen viability was under the influence of both the types of the flower and the concentration of the HBR. The highest pollen viability (96%) was obtained from both functional male and bisexual flowers treated with 0.1 mg L?1 HBR. Germination ratio, on the other hand, was only affected by the hormone concentrations, and it increased significantly as the concentration was higher.  相似文献   
54.
An experiment was conducted to determine the effects of supplemental dietary l-carnitine, chromium picolinate (Cr-Pic) and their combination on growth performance and serum total protein, cholesterol, triglyceride and glucose of rainbow trout (Oncorhynchus mykiss). A total of 276 rainbow trout were randomly allocated to four groups. Fish (average initial body weight = 151 ± 1.69 g) were fed a basal diet without supplemental l-carnitine and chromium picolinate in the control group. The basal diet was supplemented with either 500 mg/kg l-carnitine, 1.6 mg/kg chromium picolinate or 500 mg/kg l-carnitine plus 1.6 mg/kg chromium picolinate for experimental groups 1 (C), 2 (Cr-Pic) and 3 (C + Cr-Pic), respectively. Fish were fed twice a day to apparent satiation for 58 days. Weight gain, growth rate, feed consumption and feed conversion ratio (feed/gain) were calculated for the whole period. At the end of the study, six fish were chosen randomly from each tank to represent the experiment and frozen at −20°C for subsequent dorsal muscle analysis. The results showed no significant differences in final body weight, weight gain or feed conversion ratio among groups. There were also no significant differences in serum total protein, cholesterol, triglyceride or glucose concentrations among groups. Significantly higher lipid concentration of dorsal muscle was observed in experimental groups 1 and 3. In conclusion, supplemental dietary l-carnitine, chromium picolinate and their combination have no beneficial effects on improving growth performance and feed conversion ratio in rainbow trout. However, dietary l-carnitine slightly increased lipid concentration in dorsal muscle of rainbow trout.  相似文献   
55.
Rye (Secale cereale L.) is a valuable source for alien chromosome translocations in wheat breeding, due to its capability to grow and sustain under harsh environmental conditions. Wheat germplasm with 1AL.1RS and 1BL.1RS wheat-rye chromosome translocations have been used worldwide by breeders. Determining 1AL.1RS and 1BL.1RS translocations in wheat is therefore of important practical value for wheat improvement. In this study, nine rye-specific markers detecting the rye chromosome 1RS in wheat background were evaluated. The markers PAWS5/S6, SCM9 and O-SEC5′-A/O-SEC3′-R amplified specific bands associated with 1AL.1RS and 1BL.1RS translocations. These three markers therefore provide a quick and reliable tool to identify and to discriminate these two wheat-rye translocations in wheat background. Six out of nine rye specific markers were subsequently used to determine the frequency of these translocations in commonly grown bread and durum wheat cultivars from Turkey. One hundred seven wheat cultivars and landraces were molecularly screened. Among them, only 4% (‘Seri-82’, ‘Yıldız-98’, ‘Tahirova’, and ‘Osmaniyem’) harbor the 1BL.1RS translocation whereas the 1AL.1RS translocation was not found. The information provided here will contribute to the creation of new Turkish wheat populations with a larger genetic diversity necessary for future requirements.  相似文献   
56.
This study investigated the effect of high humic substance (HS) levels (0, 500, 1000, and 2000 mg HS kg?1) on growth and nutrient concentrations of corn grown on calcareous soils. For these, soil samples were collected from the six different provinces of Turkey. According to the average values, HS levels had no significant effect alone on dry weight, nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) concentrations. Soil differences significantly affected dry weight, N, Mg, and Cu concentrations (p ≤ 0.05). Looking at HSxsoil interactions on K, Ca, Fe, and Mn concentrations, it could be seen that there was no effect or that the effect was negative. Only plant Fe concentrations obtained from Konya and Urfa provinces were positively affected from HSxsoil interaction. It was concluded that high level of HS had no or negative effect on corn growth and some nutrient concentration under calcareous conditions.  相似文献   
57.
This study aimed to compare thickness of the capsule, corium, and soft tissues measured ultrasonographically and macroscopically in selected regions of bovine claws. A hundred and twenty claws (n = 120) of 15 healthy Holstein bovines were obtained. After cleaning the claws, ultrasonographic measurement of the capsule, corium, and soft tissues was performed while submerging the claws in a water bath. Macroscopic measurements were taken after cutting of the claws axially. These values were compared statistically. According to the macroscopic measurements, the mean thickness ± standard deviation (SD) of the capsule for dorsal wall and sole was 6.2 ± 0.1 and 9.5 ± 0.4 mm, respectively. The thickness of the corium and soft tissues for dorsal wall and sole was 4.5 ± 0.1 and 5.3 ± 0.1 mm, respectively. Ultrasonographically, the mean thickness ± SD of the capsule for dorsal wall and sole was 4.7 ± 0.1 and 7.8 ± 0.3 mm, respectively. The thickness of the corium and soft tissues for dorsal wall and sole was 4.3 ± 0.1 and 5.9 ± 0.2 mm, respectively. Findings demonstrated that ultrasonography can be reliably to measure of the thickness of the hoof capsule, corium, and soft tissue in bovine claw.  相似文献   
58.
Nile tilapia (Oreochromis niloticus) and silver carp (Hypophthalmichthys molitrix) held in timed-pulse feeding chambers were provided water dominated either by green algae (Scenedesmus, Ankistrodesmus and Tetraedron) or by cyanobacteria (Microcystis) to compare filtration rates (FRs). FRs were expressed as suspended particulate organic carbon (POC)/kg wet fish weight/h and as phytoplankton units filtered based on counts. Nile tilapia and silver carp filtration significantly reduced phytoplankton number of both taxonomic groups with the larger phytoplankton being filtered proportionally more than the smaller phytoplankton. Nile tilapia FR of green algae was significantly higher than silver carp; however, silver carp FR of cyanobacteria was higher than Nile tilapia. Ivlev's 90% saturation FRs (FR90) in green-algal and cyanobacterial water sources were 702 and 812 mgC/kg/h for Nile tilapia and 414 and 1028 mgC/kg/h for silver carp, respectively. Silver carp were observed to reach these FR90 values at lower POC concentrations than Nile tilapia with both green algae and cyanobacteria.  相似文献   
59.
To determine the most effective dose of arabinogalactan-protein (AGP) in regeneration medium, mature embryos of genotypes in three different ploidy levels (Triticum aestivum L. cv. Ikizce-96, Triticum durum Desf. cv. Mirzabey and Hordeum vulgare L. cv. Tokak) were used to establish an efficient plant regeneration system for cereals. Percentage of callus production, capacity of regeneration were calculated, and also culture effect, root, stem, and total plant length of regenerant plants were observed in six different regeneration media (MS control, MS+2, 5, 7, 10, 12 mg L-1 AGP) in these three different genotypes. According to the results, the highest amount of callus production was found in Ikizce-96 as 93.75% using 5 mg L-1 dicamba and 1 mg L-1 kinetin in induction medium. However, the most improved callus was observed in diploid barley Tokak as 179.95 mg in weight and 6.18 mm in diameter, respectively. The highest regeneration capacity was observed in the dose of 5 mg L-1 AGP in MS of all the genotypes and hexaploid wheat Ikizce-96 gave the best results with the highest regeneration capacity and culture effects (94.86 and 92.5%) in the same dose of AGP. These results indicated that effective dose of AGP in regeneration medium increase plant regeneration in calli derived from cereal mature embryos.  相似文献   
60.
A study to determine and compare the sensitivities and specificities of the comparative cervical tuberculin (CCT) and gamma-interferon (IFN-) tests for the diagnosis of bovine tuberculosis was conducted on 30 zebu oxen. The results of the tests were compared with the presence of acid-fast bacilli found by bacteriological culturing and histopathological examinations. The sensitivity and specificity of CCT test were found to be 90.9% and 100%, respectively. Those of the commercial IFN- test were determined to be 95.5% and 87.7%, respectively. No significant differences were found between the sensitivities (Yates' corrected 2 = 0.32; p = 0.57) or the specificities (Yates' corrected 2 = 2.54; p = 0.11) of the two tests. Furthermore, a positive correlation (r = 0.76) was recorded between the increase in skin thickness following injection of bovine purified protein derivative (PPD) and the optical density in the gamma-interferon assay with bovine PPD. On the other hand, the correlation (r = 0.47) between the change in skin thickness following injection of avian PPD and the optical density in the gamma-interferon assay with avian PPD was relatively weak. On the basis of this preliminary investigation, it was concluded that the choice between the two tests depends on their cost and simplicity and on livestock management and time factors rather than on their respective diagnostic value.  相似文献   
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