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71.
The results of evaluating resistance to leaf rust pathogen in Russian common wheat varieties recommended for growing in the Russian Federation are given. Their diversity with respect to Lr genes is assessed with the use of phytopathological and molecular methods and representativeness in growing regions is analyzed. A low genetic diversity among resistant varieties with domination of genes Lr9 and Lr19 and their confinement to Volga, Ural, and West Siberian regions are revealed.  相似文献   
72.
In this study the clinical and histopathological effects of topically applied tripeptide-copper complex (TCC) and zinc oxide on open-wound healing in rabbits was evaluated. Eighteen New Zealand rabbits were divided into three groups: TCC, zinc oxide and no treatment. One full thickness wound was created on each side of the dorsal midline in each rabbit. Wound margins were traced on days 0, 7, 14, and 21 and topical TCC and zinc oxide were applied daily for 21 days to each rabbit in the respective treatment groups. The mean unhealed wound area was significantly smaller in the TCC than in the zinc oxide group on day 7, but it was significantly smaller in the TCC group than in to the control group on days 7, 14 and 21. The mean percentage of wound contraction on day 7 was significantly higher in the TCC than in the zinc oxide group; however, it was significantly higher in the TCC group than in the control group on days 7, 14 and 21. Median time for the coverage of the wound bed with granulation tissue was significantly shorter in the TCC group than in the other groups. Filling of the open wound with granulation tissue to skin level was significantly slower in the control group than in the other two groups. Neutrophil counts decreased regardless of the group in parallel with healing, while neovascularization was best observed in the TCC group. The results suggest that TCC is a better choice in the treatment protocols of open wounds in rabbits than zinc oxide.  相似文献   
73.
A polymerase chain reaction (PCR) based approach involving the directed amplification of minisatellite DNA region (DAMD-PCR) was used to identify accession specific DNA markers and study genetic relationships between and within 15 accessions corresponding to 11 species in genus Capsicum. A touch down PCR profile and unique chemical concentration of ingredients resulted in reproducible and reliable DNA amplifications. The number of amplified products varied from 1 to 12 fragments depending on the template DNA and the primers. The DAMD-PCR technique provided a total of 38 accession specific DNA markers (diagnostic DAMD-PCR) which can be utilized in accession identification, preservation and genetic studies of Capsicum germplasm. Based on 1,292 polymorphic and monomorphic DNA markers directed with 22 minisatellite specific primers, accessions were divided into four major groups, three of which corresponded to the three distinct Capsicum complexes. Capsicum chacoense was found to be the most distinct species.  相似文献   
74.
Journal of Soils and Sediments - The aim of this study was to compare organic and inorganic amendments namely citric acid, ammonium nitrate, compost, and titanium dioxide nanoparticles (TiO2 NPs)...  相似文献   
75.
Jojoba (Simmondsia chinensis (Link) Schneider) is an obligate cross-pollinated shrub native to the Sonora desert. The most valuable product of the jojoba seeds is the liquid wax or jojoba oil which is marketed extensively in the cosmetic industry. Differing from the most of the cultivated crop species, jojoba has slow-growing habit, difficulties in the determination of sex at the early seedling stages, a male-biased ratio and low seed yield. In jojoba, the development of molecular strategies for the identification of sexes at early stages has been a priority in plantations and breeding programs. Two previous studies reported two candidate male-specific jojoba DNA markers. However, present study indicated that these markers were not useful in jojoba sex identification. A reliable gender diagnostic marker for jojoba is, therefore, needed. In the present study a novel jojoba male-specific touch-down polymerase chain reaction based DNA marker (JMS900) was reported using a total of 120 individual jojoba plants bulked into 16 samples. This sex specific DNA marker may have considerable theoretical and practical applications in the establishment of jojoba plantation and breeding studies.  相似文献   
76.
The present study describes the detection of sheeppox virus antigen in various lamb tissues, using an immunohistochemical technique, in sheeppox cases which occurred naturally. Sheeppox viral antigen was detected in the cytoplasm of sheeppox cells and degenerated epithelial cells of the skin, lungs and digestive tract involving typical sheeppox lesions. Nuclear staining was also observed in some typically deformed nuclei of sheeppox cells. The immunostaining of sheeppox virus showed a correlation with the presence of sheeppox cells and degenerated epithelial cells resembling them. Additionally, in order to confirm the presence of sheeppox virus in the skin and lung samples, direct electron microscopy was performed and sheeppox virus was only demonstrated in two skin samples.  相似文献   
77.
78.

Purpose

Soil compaction resulting from mechanisation of forest operations reduces air permeability and hydraulic conductivity of soil and can result in the development of hydromorphic and/or anoxic conditions. These hydromorphic conditions can affect physico-chemical properties of the soils. However, early detection of these effects on mineralogical portion of soils is methodologically difficult.

Materials and methods

To analyse the effects of soil compaction on iron minerals in loamy Luvisol, three compacted and three non-compacted soil profiles up to the depth of 50 cm were collected from an artificially deforested and compacted soils after 2 years of treatment. Soil was compacted with the help of 25 Mg wheeler’s load to increase the dry bulk density of soil from 1.21?±?0.05 to 1.45?±?0.1 g cm?3. Soil samples were analysed by X-ray diffraction (XRD) and were treated by citrate bicarbonate (CB) and dithionite citrate bicarbonate (DCB) under controlled conditions. Major and minor elements (Fe, Al, Mg, Si and Mn) were analysed by ICP-AES in the CB and DCB extracts.

Results and discussion

It was found that X-ray diffraction is not an enough sensitive method to detect the quick mineralogical changes due to soil compaction. Results obtained from CB-DCB extractions showed that soil compaction resulted in larger CB and smaller DCB extractable elements as compared to non-compacted soil. Labile Fe was found 30 % of total Fe oxides in compacted soil against 10–14 % in non-compacted soils. Compaction thus resulted in Fe transfer from non-labile to labile oxides (s.l.). Results showed that soil compaction leads to the reduction of Fe3+ to Fe2+. The effects of hydromorphic conditions due to soil compaction were observed up to the depth of 35 cm in forest soil profile. Furthermore, a close association of Al with Fe oxides was observed in the soil samples, while Mn and Si were mainly released from other sources, Mg showing an intermediate behaviour.

Conclusions

Hydromorphic conditions owing to soil compaction affect the mobility and crystallisation process of iron mineral. CB-DCB selective extraction technique, in contrast to XRD technique, can be effectively used to examine the possible effects of soil compaction on iron minerals.
  相似文献   
79.
Management of anthracnose caused by Colletotrichum spp. is the most important issue for the tropical fruit industry because of resulting financial losses. Antifungal effects of gum arabic (GA) (10%), lemongrass oil (LG) (0.05%), cinnamon oil (CM) (0.4%), and their combinations were investigated in vitro and in vivo for controlling postharvest anthracnose of banana and papaya. LG at 0.05% and 0.4% CM showed fungicidal effects against Colletotrichum musae and Colletotrichum gloeosporioides, causal organisms of banana and papaya anthracnose, respectively. GA alone did not show any fungicidal effects while the combination of 0.05% LG and 0.4% CM with Ten percent GA alone showed more fungicidal effects. However, potato dextrose agar (PDA) medium modified with 10% GA combined with 0.4% CM showed the most promising results among all treatments against C. musae and C. gloeosporioides in suppressing the mycelial growth (73.4%) and (70.0%) and spore germination inhibition (88%) and (85%), respectively. In vivo studies also revealed that 10% GA combined with 0.4% CM was the optimal concentration in controlling decay (80%) and (71%), showing a synergistic effect in the reduction of C. musae and C. gloeosporioides, respectively, in artificially inoculated bananas and papayas. The results regarding quality evaluation also confirmed the efficacy of 10% GA combined with 0.4% CM coatings since ripening was significantly delayed, in terms of percentage weight loss, fruit firmness, soluble solids concentration and titratable acidity. The results suggest the possibility of using 10% gum arabic combined with 0.4% cinnamon oil as a biofungicide for controlling postharvest anthracnose in major tropical fruit such as banana and papaya.  相似文献   
80.
The present study was designed with the objective of improving the nodulation and growth of chickpea (Cicer arietinum L.) by integrating co-inoculation of Rhizobium sp. (Mesorhizobium ciceri) and plant growth promoting rhizobacteria (PGPR) carrying ACC (1-aminocyclopropane-1-carboxylate) deaminase activity with P-enriched compost (PEC) under irrigated and rainfed farming systems. PEC was prepared from fruit and vegetable waste and enriched with single super phosphate. The results demonstrated that co-inoculation significantly (P?<?0.05) increased the number of nodules per plant, nodule dry weight, pods per plant, grain yield, protein content, and total chlorophyll content under irrigated and rainfed conditions compared to inoculation with rhizobium alone. Integrating PEC with co-inoculation showed an additive effect on the nodulation and growth of chickpea under both farming systems. Analysis of leaves showed a significantly (P?<?0.05) higher photosynthetic rate and transpiration rate in comparison with inoculation with Rhizobium. Compared to irrigated farming system, co-inoculation with PEC under rainfed conditions was more beneficial in improving growth and nodulation of chickpea. Post-harvest soil analysis revealed that the integrated use of bioresources and compost enhanced microbial biomass C, available N content, dehydrogenase, and phosphomonoesterase activities.  相似文献   
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