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121.
Phosphorus (P) is one of the least available mineral nutrients to the plants in calcareous and alkaline soils. In this study, we investigated the synthesis, characterization and use of synthetic nano-hydroxyapatite (NHA), P uptake by plants as well as its residual effects. Soluble P source (H3PO4) was also included as treatment for comparison. NHA prepared by wet chemical techniques, characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and elemental dispersive X-ray (EDX) analysis. NHA and H3PO4 were applied at a rate of 200 mg kg?1 to find out their effects on phosphorus nutrition and growth of lettuce on the low and high calcareous soil. In addition to this, residual effects of NHA and H3PO4 were also determined for lettuce plants grown after first lettuce plants in the both soil. Dry weights of the first and second lettuce plants grown in low and high calcareous soil were significantly increased by applied phosphorus regardless of the source. NHA seems to be more effective than that of ordinary phosphorus source (H3PO4-P) on growth and P concentration of the lettuce plants. The promising results of this study needs to be supported with long term field studies regarding the uptake, translocation and interactions of nano-P with the other elements.  相似文献   
122.
Ding  Xuhan  Xu  Guang  Kizil  Mehmet  Zhou  Wei  Guo  Xingyun 《Water, air, and soil pollution》2018,229(7):1-11
Water, Air, & Soil Pollution - Lead is known to be a highly toxic metal; it is often found in soils with the potential to be incorporated by plants. Here, the bioaccumulation of lead by...  相似文献   
123.
Wild Cicer species are considered as useful genetic resources for resistance to biotic and abiotic stresses due to limited resistance in cultivated chickpeas. As a wild perennial species in the genus Cicer L., Cicer isauricum P.H. Davis is an endemic species to Turkey and endangered status according to the International Union for Conservation of Nature criteria. Here we report on its eco-geographic distribution and environmental stresses that affect the species, and advocate for its in situ and ex situ conservation. A new population of the species was discovered in Geyikbay?r?, Güllük Mountains in Antalya, Turkey. Cicer isauricum not only suffers from significant biotic stresses such as ascochyta blight [Ascochyta rabiei (Pass.) Labr.], pod borer (Helicoverpa armigera Hübner) and broomrape (Orobanche sp.), but is also subjected to drought and heat stress in its habitat. Infection with ascochyta blight in natural habitats was diagnosed by molecular techniques, and pod borer and broomrape were observed only phenotypically. PCR amplification of the internal transcribed spacer region of genomic DNA from cultured fungal isolates, yielded sequences with 100% nucleotide identity with the corresponding sequence in GeneBank for Didymella rabiei Kovachevski (anamorph: A. rabiei). The pathogen may have co-evolved with C. isauricum in the newly discovered site. Because C. isauricum is exposed to drought and accompanying heat stress in its natural habitat, it appears able to tolerate heat stress up to 45 °C during podding stage and terminal drought in late summer from its woody, deep rooting. C. isauricum bears multiple flowers per axil, a potentially useful trait in cultivated chickpea. In conclusion, C. isauricum is a potential genetic source for resistance to biotic and abiotic stresses, in need of greater protection due to its endangered status.  相似文献   
124.
125.
A total of 95 samples of Meloidogyne incognita (60), Meloidogyne javanica (28) and Meloidogyne arenaria (7) collected from West Mediterranean region of Turkey were tested for identifying races of the nematodes using the North Carolina Differential Host Test. Races 2 and 6 of M. incognita were identified in 58 and 2 samples, respectively. Race 1 of M. javanica was identified from all 28 samples. Races 2 and 3 of M. arenaria were identified in 5 and 2 samples, respectively. The results also showed that two races of M. incognita and all races of M. javanica did not attack on pepper cv. California Wonder. These findings may contribute to improving resistant varieties and may also provide basis for developing a cropping system to control root-knot nematodes.  相似文献   
126.
The basic aim of the sprinkler irrigation method, as in other irrigation methods, is to apply irrigation water as uniformly as possible to the root zone. The uniform distribution of the applied water in sprinkler irrigation depends on factors such as sprinkler type, number and size of nozzles, arrangement of sprinklers, working pressure and the speed and direction of the wind. Sprinkler and lateral spacing should be determined by also taking the speed and direction of the wind into consideration. The aim of this study was to determine the application limits and the curves of water distribution under different working pressures, spatial arrangement and nozzle diameters under field conditions of some irrigation sprinklers which are widely used in Turkey. The objective was to determine the most appropriate system arrangement by using a computer program called CATCH3D. Five sprinklers were tested in the experimental area of Ondokuz Mayis University Campus and their water distribution characteristics identified. The most suitable operating parameters for Bereket 3: 12 x 18 m, Bereket 2: 12 x 18 m, Egeyildiz 6 x 18m, Goktepe 6 x 12 m and for Atesler sprinkler 12 x 18 m arrangement type were determined.  相似文献   
127.
Clinoptilolite (CLI, a natural zeolite) incorporated into the diet at 1.5 and 2.5 per cent were evaluated for their ability to reduce the deleterious effects of 2.5 mg total aflatoxin (AF) kg(-1)diet on broiler chickens from 1 to 21 days of age. In total 360 broiler chicks were divided into six equal treatment groups (control, AF, CLI (1.5 per cent), AF plus CLI (1.5 per cent), CLI (2.5 per cent) and AF plus CLI (2.5 per cent)). When compared with the controls, AF treatment significantly decreased serum total protein, albumin, inorganic phosphorus, uric acid, total cholesterol and the values of haematocrit, red blood cell counts, mean corpuscular volume, haemoglobin, thrombocyte counts, percentage of monocyte counts; increased values of white blood cell and heterophil counts. The addition of CLI (1.5 per cent) and CLI (2.5 per cent) to the AF -containing diet reduced the adverse effects of AF and should be helpful in a solution to the aflatoxicosis problem in poultry.  相似文献   
128.
Field experiments were carried out in the 2004 and 2005 growing seasons on drip irrigated dwarf green beans (Phaseolus vulgaris, humilis). Soil water content (SWC), spectral reflectance and yield were monitored. Based on these data crop evapotranspiration (ETc), soil water deficit index (SWDI), water use efficiency (WUE) and four separate spectral indexes were calculated. In order to determine use opportunities of spectral indexes for estimation of yield, SWDI and WUE, some statistical analyzes were made. Results showed that spectral indexes could be used for monitoring of yield, SWDI and WUE. Especially, Soil Adjusted Vegetation Index (SAVI) had the highest correlations with all three of the parameters. The estimation procedure which was given in this study has a potential use either during, or at the end of the growing season. Estimated values of WUE and SWDI were 3.2 (kg m?3) and 0.12, respectively, through SAVI and the given procedure, indicates the optimal water use and yield conditions for dwarf green beans. At this situation, probably ETc was 580 mm and yield was 25.5 t ha?1.  相似文献   
129.
Abstract

Biochar is a pyrolyzed biomass produced under limited oxygen or oxygen absent conditions. Few investigations have been conducted to determine the combined effect of biochar with chemical fertilizer on growth, yield and nutrient distribution pattern in root, shoot and grain in wheat as well as changes in soil physiochemical properties. This research was designed to study the combined effect of chemical fertilizer and rice straw-derived biochar on soil physio-chemical properties, growth, yield and nutrient distribution pattern within wheat plant tissue and grain. Results showed that rice straw biochar caused a significant decrease in soil pH and increase in soil organic matter as well as nutrients like total nitrogen (TN), potassium (K), magnesium (Mg) and boron (B) due to incubation. Result also showed that root biomass and straw did not differ between Bangladesh Agricultural Research Council (BARC) and ½ BARC?+?rice straw biochar treatment. Similarly, thousand grain weight and grain yield did not differ between the same treatments. The phosphorus concentration in wheat grain was highest in ½ BARC?+?rice straw biochar as compared to other treatments. The use of rice straw biochar in addition to the chemical fertilizers in wheat production systems is an economically feasible and practical nutrient management practice. Our findings urged that reduction of chemical fertilizer application is possible with supplementation of rice straw biochar.  相似文献   
130.
The most significant focal points of the embryo transfer technology are as follows: the selection of donors, the response of the selected donor to the superovulation protocol and the obtained number of the transferable embryos. For this purpose, it is suggested that donor selection can be done by anti‐Müllerian hormone (AMH) levels, and embryo production is evaluated. AMH is secreted by the granulosa cells of primordial, pre‐antral and antral follicles below 4 mm in the ovary, independent of FSH. Therefore, the aim of this study was to investigate the relationship between serum AMH levels and the number of corpus luteum (CL), total embryos and transferable embryos that were shaped after a uniform superovulation protocol. For this reason, 48 Simmental cows, which were located at General Directory of Agricultural Enterprises (region, province, etc. instead of the general directorate), were used as donors for the embryo transfer. Blood samples were taken at random, regardless of the stage of animal's sexual cycle. AMH levels were measured by enzyme‐linked fluorescent assay (ELFA) method of the miniVIDAS® (bioMérieux SA) using AMH Bovine Test Kit. According to the statistical analyses of the obtained data, AMH levels were positively correlated with CL and total embryos (p < .05). No significant correlations between AMH and transferable embryos were approved (p > .05). It was also determined that each 200 pg/ml increase in serum AMH level resulted in one increase in CL number. Overall, considering the positive correlation between AMH level and the obtained number of CL and total embryos after a superovulation treatment, it was concluded that measuring blood AMH level prior to any further costly implementation may be an effective method in donor selection.  相似文献   
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