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21.
ABSTRACT

Scientific evidence suggests forest cover across the world is gradually decreasing while the world’s population is rapidly increasing. In line with this, the demand on raw wood is also increasing, making it impossible for the already limited natural resources to meet human needs in proportion to the increasing population size. To counter this, there is a need to increase the variety and availability of timber through genetic improvement. This has been seen in genetic improvement studies in forestry which have resulted in seed orchard establishments; however, the genetic variation in these seed orchards continues to be a topic of debate. This study aims to determine the clonal variation in chemical characteristics in a Hanönü (Kastamonu) Günlüburun black pine (Pinus nigra Arnold. subsp. pallasiana (Lamb.) Holmboe) seed orchard. The analysis shows differences between the clones were seen at the 99.9% confidence level. Ash content, NaOH, extractive substance, and hot water solubility exhibited the highest heritability scores, according to the heritability estimates of the clones in the seed orchard. However, hemicellulose content showed an extremely low H2 (0.1).  相似文献   
22.
The infection of gastrointestinal helminths in livestock is routinely diagnosed by microscopical examination of faecal samples for the presence of ova/eggs but this approach becomes ineffective for the seasonally egg producing trematodes. Therefore, an alternative approach to detect the coproantigens of liver and rumen amphistomes, Gigantocotyle explanatum and Gastrothylax crumenifer respectively, infecting Indian water buffalo Bubalus bubalis, was undertaken using ELISA, immunodot and countercurrent immunoelectrophoresis (CCIEP). The hyperimmune polyclonal antisera were separately raised in rabbits against excretory/secretory (ES) antigens of both the flukes under study. An overall 70% buffalo faecal samples were tested positive for G. crumenifer and 75% for G. explanatum in Aligarh region. The ELISA results reflected higher infection intensity among individual buffaloes that was also observed at necropsy. Using the respective homologous hyperimmune antiserum, 55% buffaloes tested positive for G. crumenifer and 65% positive for G. explanatum in immunodot assay. Further, the faecal samples with high absorbance values in ELISA and strong immunodot reaction tested positive in CCIEP. The analysis of CCIEP result revealed two and one precipitin bands in G. crumenifer and G. explanatum respectively, indicating prominent antigenic differences in the coproantigens of these two parasites. Taken together, it is suggested that polyclonal antibodies could be conveniently used for the detection of coproantigens by ELISA and immunodot methods, particularly during the non-egg producing phase of the seasonally regulated reproductive cycle of the rumen amphistome G. crumenifer. It is concluded that the coproantigen detection is a good alternative over conventional method for the diagnosis of amphistomosis in livestock; however, further studies are required on a larger sample size of field buffaloes to augment the reproducibility of the present results.  相似文献   
23.
Journal of Plant Diseases and Protection - Crown rot, caused by Fusarium culmorum and Fusarium pseudograminearum, is one of the most pervasive diseases of wheat throughout the world. Fusarium...  相似文献   
24.
A derivative of an optical brightening agent (organic dye), i.e., 2,6-dibromo-4-flouroaniline (synthesized and reported previously) has been chemically bonded to cotton fabrics through a coupling agent, i.e., 3-(2-aminoethylamino)- propyltrimethoxy silane. These chemically treated cotton fabrics have been characterized by FTIR spectroscopy, color observation, tear properties determination, and UV-DRS analysis. The relevant spectra of FTIR confirm chemical bonding of the silane with cotton on one end and with the dye on the other. Comparison of the various treated and untreated cotton samples before and after washing by visual observations confirms the claim of chemical bonding of the dye with the cotton. The consistent decreasing patterns observed in tear strengths of the treated cloths with increase in concentration of the respective chemical validate modification of the cotton cloths. UV-DRS analysis of the modified cotton cloths show that the reflectance decreases with the use of silane.  相似文献   
25.
The pattern of genetic diversity among 92 genotypes of soybean from 5 different origins/sources (Pakistan, the USA, Asian Vegetable Research Development Centre (AVRDC), Japan and North Korea) was analyzed using randomly amplified polymorphic DNA markers. Out of 20 random primers 6 tested, 10 were polymorphic among genotypes and they yielded 107 markers, with an average of 10.7 markers per primer. The proportion of polymorphic bands within genotypes ranged from 0.47 to 0.71 with an average of 0.59. Pakistani and US genotypes exhibited the highest number of polymorphic bands (95%), while North Korean genotypes revealed the lowest (60%). The mean band frequency of the primers among genotypes was 0.57 with a range of 0.08–0.99. The Shannon’s index and Nei’s genetic diversity index revealed that primer OPF-06 showed maximum genetic diversity among the genotypes. Dendrogram constructed using Unweighted Pair Group Mean Average (UPGMA) method divided the genotypes into 5 main groups consisting of 13 clusters. The results of cluster analysis indicated that the genetic diversity between Pakistani and US or AVRDC genotypes is much larger than that between Pakistani and North Korean or Japanese genotypes. The Pakistani genotypes had distinct bands from plant introductions. Therefore, the Pakistani genotypes may be useful to soybean breeders.  相似文献   
26.
The influence of all-plant-based diet on fingerling blunt snout breams (Megalobrama amblycephala) was tested by examining growth performance, anti-stress properties and related gene expression. Healthy fish were randomly divided into triplicate groups per dietary treatment and fed with different formulated diets. The results showed that both weight gain, specific growth rate and protein efficiency ratio of all-plant-based diet group were significant higher than those of the control (p < 0.05). In contrast, FCR of all-plant-based diet group was significantly lower than that of the control (p < 0.05). Therefore, all-plant-based diets could not affect the growth performance of blunt snout breams. Compared to the control group, the lysozyme levels in serum and mucus, and glutamic-oxaloacetic transaminase activities in serum and liver decreased significantly (p < 0.05). In contrast, the glutamic-pyruvic transaminase activities in serum and liver increased significantly (p < 0.05). For blunt snout breams fed with all-plant-based diets, the superoxide dismutase activities in mucus, serum and liver as well as catalase activity in serum and liver were decreased significantly (p < 0.05) comparing with that of the control group. But malondialdehyde contents were higher (p < 0.05) in serum and liver than that of control group. The expression of HSC70 mRNA increased significantly (p < 0.05) in blunt snout breams fed with all-plant-based diet, whereas the HSP70 mRNA expression decreased significantly (p < 0.05) when compared with control group. In conclusion, all these results indicated that the application of all-plant-based diet could decrease the anti-stress properties (non-specific immunity, stress resistance and antioxidant ability) and HSP70 mRNA expression in blunt snout breams fingerling. Although all-plant-based diets could not affect the growth performance of blunt snout breams, the application of all-plant-based diet should be discreet in the production practice.  相似文献   
27.
An experiment was carried out to investigate the efficacy of rice straw and empty fruit bunch (EFB) of oil palm compost extracts either fortified or unfortified with Trichoderma harzianum on morpho-physiological growth and occurrence of Choanephora wet rot of okra. Treatments tested were water (control) (T1), rice straw (RST) compost extract (T2), Trichoderma-enriched RST compost extract (T3), empty fruit bunch of oil palm compost extract (T4), Trichoderma-enriched EFB compost extract (T5), aqueous suspension of Trichoderma (T6), and a fungicide Dithane M-45® (2 g l−1 of water) (T7). The experimental results revealed significant variations amongst the treatments in respect of morphological characters, e.g. shoot length, tap root length, number of leaves per plant, and leaf area. The shoot and tap root length, number of leaves per plant, leaf area were significantly (P ≤ 0.05) higher in Trichoderma-enriched RST compost extracts (T3) followed by Dithane M-45® (T7), Trichoderma-enriched EFB extracts (T5), RST (T2), EFB (T4) and aqueous suspension of T. harzianum (T6) in both Choanephora inoculated and uninoculated (control) plots. Similarly, net photosynthetic rate and chlorophyll content were higher in plants receiving Trichoderma-enriched RST compost extracts (T3) with 76.2% reduction in Choanephora wet rot incidence when compared with rest of the treatments. These experimental results revealed that morpho-physiological characters of okra could be modified by the application of Trichoderma-enriched compost extracts. This suggests that use of Trichoderma-enriched compost extracts would be more beneficial in environmentally friendly okra cultivation and may be used as an alternative to inorganic fertilizers/fungicides to enhance plant growth and reduce disease incidence subsequently, resulting in higher yield.  相似文献   
28.
In rice, the traditional system of transplanting gives the crop a 14 to 21-day growth advantage over the weeds [1]. The transplanting also enables rice to capture space earlier. This is because the young rice plants have leverage over germinating weeds due to shading and earlier establishment of root system. The immediate flooding after transplanting limits the establishment of many weeds [2]. Similarly, in direct seeded method, the use of high seed rates could reduce weed infestation to a lar…  相似文献   
29.
The effect of inoculation of Rhizobium or Pseudomonas, or both, in the presence and absence of phosphorus pentoxide (P2O5) fertilizer on wheat yield was tested. The experiment was conducted outdoors in potted soil during two consecutive years under natural conditions. Rhizobial strain (Thal 8-chickpea nodulating bacteria) and Pseudomonas strain (54RB), both indigenous P solubilizers were applied in broth culture at seedling stage. Fertilizer in the form of P2O5 was an additional treatment applied at sowing time. Results revealed that inoculation of Pseudomonas strain in presence of phosphorus (P) fertilizer increased yield up to 41.8% when it was compared with only P fertilizer applied. Co-inoculation of Rhizobium and Pseudomonas strains with the P2O5 treatment however resulted in increased grains yield by 10% over the P2O5 treatment alone. It is inferred that inoculation with Rhizobium and Pseudomonas combined with P2O5 is not only environmentally beneficial but also economically sound and productive, with wheat yield increases of 10% to 42%.  相似文献   
30.
Mapping of QTL controlling tocopherol content in winter oilseed rape   总被引:5,自引:0,他引:5  
V. Marwede    M. K. Gul    H. C. Becker  W. Ecke 《Plant Breeding》2005,124(1):20-26
Tocopherols are natural antioxidants in vegetable oils and are important dietary nutrients. Enhanced tocopherol content has become an important objective in oilseed rape breeding. A segregating DH population was tested for 2 years at two locations in replicated field trials. Genotypic differences occurred for α‐, γ‐ and total tocopherol content as well as α/γ‐tocopherol ratio, but highly significant genotype x environment interactions resulted in low heritabilities. Using a mixed‐model composite interval mapping approach between one and five QTL with additive and/or additive x environment interaction effects could be mapped for α‐, γ‐ and total tocopherol content and α/β‐tocopherol ratio. In addition, one to six locus pairs with epistatic interaction effects were identified, indicating a strong contribution of epistasis to trait variation. In total, the additive and epistatic effects explained between 28% (α‐tocopherol content) and 73% (total tocopherol content) of the genotypic variance in the population, with individual QTL and locus pairs contributing between 7.5 and 29.2% of variance. Considering the low heritabilities of the tocopherol traits, the results of this study indicate that marker‐assisted selection may be an efficient strategy in a breeding program for enhanced tocopherol content in rapeseed.  相似文献   
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