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11.
We investigated in vitro regeneration ability of Prunus microcarpa subsp. tortusa using various explants (root, cotyledon and hypocotyl pieces) and cytokinins [benzyladenine (BA), meta-Topolin (mT) and thidiazuron (TDZ)]. Sectioned cotyledon, root and hypocotyl pieces of in vitro grown seedlings were cultured on Nas and Read Medium (NRM) containing BA (7.5, 10, 12.5, 15 or 17.5 μM), mT (2.5, 5.0, 7.5, 10 or 12.5 μM) or TDZ (2.5, 5.0, 7.5, 10 or 12.5 μM). As a measurement of morphogenetic reaction, the ratios of regenerating explants and the numbers of primary adventitious shoots per regenerating explant were analyzed. Cotyledon explants exhibited higher regeneration ratios than hypocotyl explants, and the root explants were inappropriate for regeneration. Both BA and mT were effective on shoot regeneration but higher regenerating explant ratios were obtained when BA was used. In comparison with BA and mT, the effect of TDZ on enhancing explant regeneration ability was insignificant. Mean number of adventitious shoot per regenerating explant was between 1 and 4, and regenerating explant ratios were between 0% and 77%. The practical appliacations of the results are discussed.  相似文献   
12.
The aim of this study was to assess cellular proliferation using silver-stained nucleolar organizer regions (AgNOR) and the proliferating cell nuclear antigen (PCNA) in various tissues in the prostate of ram lambs implanted with increasing zeranol doses and to compare the sensitivity of different tissues of lamb prostate to zeranol. Twenty-four Akkaraman lambs were implanted with increasing zeranol doses, including 12 mg (n = 8), 24 mg (n = 8) and 96 mg (n = 8), with eight lambs serving as controls. After 33 days, the prostate tissues of the lambs were stained using AgNOR and PCNA techniques. The prostate tissues were divided into two compartments--the epithelial tissues, including glandular acinus, collecting duct and penile urethra, and the non-epithelial tissues, including interstitial tissue and striated muscle. AgNOR dots and PCNA index on each prostatic tissue were counted under a light microscope and were evaluated statistically. AgNOR staining in the treatment groups showed a higher score in the non-epithelial tissues than the epithelial components, whereas the PCNA index was significant in the epithelial tissues and non-epithelial tissues had very low PCNA immunostaining. According to the PCNA index, collecting duct epithelium showed more sensitivity to increasing zeranol doses and according to AgNOR counts, there was no difference of sensitivity to zeranol among tissues of the same origin. Both AgNOR counts and PCNA indexes seem to be valuable proliferating markers for the epithelial components of ram prostate, but PCNA index had no significance in relation to the non-epithelial components in contrast to AgNOR counts. Therefore, the controversial results arising from the combined use of both techniques as proliferating markers for the ram prostate should be considered in further studies.  相似文献   
13.
Disease incidence and severity was studied for winter wheat variety Bezostaya 1 and susceptible checks based on data from international nurseries from 1969 to 2010 and from 51 countries across major winter wheat production regions totalling 1,047 reports. The frequency of leaf rust and stripe rust occurrence was stable over time with marked increases in severity in 2001–2010 especially in Europe and Central and West Asia. Substantial global reductions in stem rust occurrence were recorded and attributed primarily to use of resistance genes although the recent emergence of race Ug99 makes wheat more vulnerable. The occurrence of powdery mildew remained globally stable over time. It was the most important foliar disease in Western and Southern Europe, where the frequency was very high for all time periods coupled with slight increases in severity during 2001–2010. The durable resistance of variety Bezostaya 1 to all four diseases was demonstrated in the study using comparisons of disease severities of Bezostaya 1 and the most susceptible entries. The Lr34/Yr18/Pm38 pleiotrophic set possessed by Bezostaya 1 is currently an important target for selection because it is now amenable to molecular selection. Increased use of genes like Lr34 combined with strategies to minimize cultivation of extremely susceptible varieties will contribute to long term maintenance of low and non-damaging disease levels. The durable disease resistance of Bezostaya 1, combined with its adaptability and good end-use quality, was a significant reason for its huge impact in agriculture over the last 50?years.  相似文献   
14.
A survey was conducted in the northern conifer forests of Turkey in 2003 and 2004 for the pinewood nematode, Bursaphelenchus xylophilus . Wood samples were collected from declining pine trees, located in the following target areas: Düzce, Ankara, Bolu, and Artvin. Nematodes were extracted from over 310 samples and were observed and identified. B. xylophilus was not detected in any samples. Bursaphelenchus species were only found in 6% of the samples. From the B. xylophilus -group, only the species B. mucronatus was reported. Species identification was performed from morphological characters, particularly male spicules, and by molecular analysis with ITS-RFLP.  相似文献   
15.
Bacterial cold water disease, enteric red mouth disease and frunculosis are the common bacterial diseases of fish worldwide. The etiologic agents of these diseases are Flavobacterium (F.) psychrophilum, Yersinia (Y.) ruckeri and Aeromonas (A.) salmonicida subsp. salmonicida, respectively. In this study, a multiplex polymerase chain reaction (m-PCR) method with YER8/10-Fer3/4-FP1/3 primer pairs which can identify these fish pathogens simultaneously was developed and optimized. In optimized conditions, neither false specific nor nonspecific amplification occurred. The detection limits of the m-PCR method using DNA extracts from dilutions of pure cultures of bacteria were 35 pg for Y. ruckeri and F. psychrophilum and 70 pg for A. salmonicida subsp. salmonicida. It was determined that 15 CFU Y. ruckeri and F. psychrophilum and 30 CFU A. salmonicida subsp. salmonicida could be detected by m-PCR developed using genomic DNA extracted from dilutions of the suspensions. The detection limits in the presence of tissue debris were 125 CFU for Y. ruckeri and F. psychrophilum and 250 CFU for A. salmonicida subsp. salmonicida. In conclusion, we submit that the m-PCR method developed and optimized in this study can be used for accurate and rapid identification of these bacteria.  相似文献   
16.
Prunus microcarpa C.A. Mey. subsp. tortusa is a deciduous shrub well adapted to severe winter and dry-hot summer conditions. As the first step to explore the genetic and horticultural potential of P. microcarpa C.A. Mey. subsp. tortusa, we used SSRs to elucidate the genetic variation within its populations dispersed in upper Mesopotamia. We also investigated its phylogenetic relationship with economically important Prunus species; almond, apricot, sweet cherry, peach and plums. Using 47 amplifying SSR primer pairs, 63 P. microcarpa C.A. Mey. subsp. tortusa genotypes sampled from five locations and 15 cultivars belonging to other Prunus species were assayed. The cross-species transportability of SSRs was 96% indicating a high degree of homology between P. microcarpa C.A. Mey. subsp. tortusa and the other Prunus species. The genetic distance between P. microcarpa C.A. Mey. subsp. tortusa genotypes belonging to a particular geographic site was lower than that between genotypes of different geographic origins. Cluster analysis differentiated P. microcarpa C.A. Mey. subsp. tortusa genotypes according to their geographic sites and separated them from the other Prunus species. P. microcarpa C.A. Mey. subsp. tortusa and sweet cherry, the subgenus Cerasus, were located in the same major cluster, the other Prunus species, belonging to the subgenera Amygdalus and Prunus, were located in another one. The analysis of molecular variance (AMOVA) revealed that genetic variation among individuals within populations (59.10%) was much higher than among Prunus groups (29.28%) and among P. microcarpa C.A. Mey. subsp. tortusa populations of different geographic sites (11.61%). The results indicate a substantial genetic diversity in P. microcarpa C.A. Mey. subsp. tortusa and the need of exploring a wider area to increase the chance of finding a particular genotype.  相似文献   
17.
1. This study was conducted to determine the effects of raw and heat-treated hempseed (HHS, Cannabis sativa L.) on performance, egg quality and antioxidant activity in laying hens.

2. A total of 108 laying hens, aged 36 weeks, were divided into three treatment groups with 12 replicates and each replicate contained three laying hens. The treatments were as follows: (1) Control (no hempseed), (2) 15% raw hempseed (RHS) in diet and (3) 15% HHS in the diet. Experiments lasted for 12 weeks.

3. Feed intake of the RHS group was lower than those of the control and HHS groups. Egg weight, egg mass, shell weight, shell surface area and shell thickness of the HHS group were significantly (P < 0.05) higher than that of the RHS group. Roche (DSM) colour fan values of the RHS group were higher than that of the HHS group (P < 0.01).

4. Palmitic, palmitoleic and oleic acids of egg yolk were significantly (P < 0.05) decreased in the RHS and HHS groups; however, linoleic, α-linolenic and docosahexaenoic acids (DHA) of egg yolk increased (P < 0.05) for both treatment diets compared to the control group.

5. Both RHS and HHS supplementation to layer diets did not influence malondialdehyde (MDA) and superoxide dismutase (SOD) activity and blood lipid profile.

6. It was concluded that HHS was superior in improving the egg quality of laying hens as compared to the RHS.  相似文献   

18.
Turkey's forests have been continuously facing conversion into both agriculture and pasturelands, causing not only degradation and fragmentation of forested lands but also negative changes in soil properties that have not been thoroughly investigated. In order to determine possible changes in some physical and hydrophysical soil parameters along with the dispersion ratio between natural coppice forests and the neighbouring forest‐to‐grassland converted areas, a foothill of Mount Sacinka in Artvin was chosen as a research area. Besides land use, possible effects of elevation change on soil properties due to the mountainous and moderately steep landscape of the region were also taken into consideration. The soil samples were analysed for soil texture, permeability, field capacity, bulk density, organic matter, pH and dispersion ratio. The results indicated that whereas permeability (43·05 mm h−1 in forest and 18·82 mm h−1 in pasture), field capacity (43·45% in forest and 38·08% in pasture) and organic matter (6·36% in forest and 5·34% in pasture) values turned out to be higher in forest soils, bulk density (0·91 g cm−3 in forest and 1·06 g cm−3 in pasture) and pH (5·89 in forest and 6·55 in pasture) values were low in grassland soils, meaning that conversion has negative effects on soil properties. Additionally, the mean dispersion ratios of 27·55% and 33·58% for forest and pastureland soils, respectively, indicated soil erosion problems in both land uses. In addition, as for elevation effect, forest soils especially showed better characteristics at higher elevations with high permeability, field capacity and organic matter and low pH and dispersion ratio. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
19.
Sera samples from 89 dairy cows with repeat breeding and 111 healthy pregnant dairy cows (controls) from Elazig province of eastern Turkey were tested for presence of Fasciola hepatica and Hydatid cyst antibodies by use of an indirect enzyme linked immunosorbent assay (indirect-ELISA). One hundred and twenty one (60.5%) and 93 (46.5%) cows were found to be positive to F. hepatica and Hydatid cyst antibodies, respectively. Fifty two of 89 cows (58.4%) with a history of repeat breeding were seropositive to F. hepatica, and 43 of 89 (48.3%) were seropositive to Hydatid cyst antibodies. Whereas, seropositivity rates were 62.1% (69/11) for F. hepatica and 45% (50/111) for Hydatid cyst in healthy pregnant cows (control group). There were no statistically relationship between infected and control group (P>0.05). In conclusion, we could not detect any relationship between repeat breeding and F. hepatica and Hydatid cyst infections in cattle.  相似文献   
20.
Tomato plants (cv. Primadonna F1), non-grafted, self-grafted, or grafted onto the commercial rootstocks ‘He-man’ and ‘Maxifort’, were grown in recirculating nutrient solution. The uptake concentrations (UCs), i.e. mean nutrient-to-water uptake ratios of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B, were estimated based either on depletion from the nutrient solution or on accumulation in the plant biomass. Grafting onto both commercial rootstocks increased the total plant biomass. Hetero-grafting also increased the leaf N, Ca, and Cu concentrations but decreased those of Mg and Fe in comparison with self- and non-grafted plants. The mean UCs of N, Ca, and Cu were higher in plants grafted onto both commercial rootstocks in comparison with self- and non-grafted plants. However, hetero-grafting also raised the UCs of P, Fe, Mn, and B, because of an increased deposition of these nutrients to the roots in comparison with self-rooted plants. The method used to estimate the UCs, i.e. nutrient removal from the recirculating nutrient solution vs. nutrient recovery from plant biomass per volume unit of transpired water, resulted in similar values for N, Ca, Zn, and Cu, but had a significant impact on those of P, K, Mg, Fe, Mn, and B.  相似文献   
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