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81.
[目的]了解新疆库米什一处金矿土壤可培养细菌的多样性及建立菌种资源库.[方法]采集库米什金矿土壤样品,采用两种不同培养基(LB,TSB)分离纯化细菌,对其进行形态观察(菌落及细胞)、生理测定、16SrDNA测序和系统进化分析.[结果]从两种培养基上总共得到50株细菌,根据基于16S rDNA的系统进化分析表明,50株菌分别属于3个大类群:厚壁菌门(Firmicutes ),放线菌门(Actinobacteria),γ-变形菌纲(γ-Proteobaeteria),12个属,30个分类单元.其中芽抱杆菌属(Bacillus)为优势细菌种群,占已测种群的63.3;.菌株L10-5与Bacillus foraminis (AJ717382)有96.463;的相似率,可能为潜在新种.[结论]库米什金矿土壤可培养细菌具有较高的多样性,存在潜在新菌种资源,值得进一步研究.  相似文献   
82.
Since the dissolution of polyolefins is a chronic problem, melt processing has been tacitly accepted as an obligation. In this work, polypropylene (PP) was modified on molecular level incorporating poly(ethylene glycol) (PEG) as graft segment (PP-g-PEG) in a range of 6 to 9 mol%. Gold nanoparticles were nucleated in the presence of the copolymer chains via redox reaction. The dissolution of the amphiphilic comb-type graft copolymers containing gold nanoparticles (80 nm in diameter) was achieved in toluene and successfully electrospun from its solution. The diameter of composite fibers was in the range from 0.3 to 2.5 μm. The design of the structurally organized copolymer fiber mats provided a support medium for the nanoparticles enhancing the active surface area for the catalytic applications. The resulting composite fibers exhibited rapid catalytic reduction of methylene blue (MB) dye in the presence of sodium borohydride (NaBH4) compared to corresponding composite cast film.  相似文献   
83.
This paper examined the impact of National Special Program for Food Security (NSPFS) on the beneficiaries through a qualitative measurement of the food security status of the beneficiaries. A food insecurity index was estimated to measure the well-being of the beneficiaries as affected by the impact of the program. Beneficiaries were classified into four categories: food secure (41%), food insecure without hunger (46%), food insecure with moderate hunger (11%), and food insecure with severe hunger (2%). Perceptions of beneficiaries were measured. In conclusion, the program has had a positive impact and enhanced food security among the Nigerian beneficiaries. It is not without its short comings which include delayed and untimely disbursement of funds and lack of output markets, irrigation facilities, production inputs and adequate training on technology know-how. The default rate and number of debtors remain high among beneficiaries. Efforts should be made to correct the short comings to improve the effectiveness of the program and justify the huge financial resources that have been committed.  相似文献   
84.
We investigated individual and combined effects of B toxicity and salinity in the presence or absence of silicon on the shoot growth, concentrations of sodium (Na), chloride (Cl), boron (B) and silicon (Si), and stomatal resistance (SR), lipid peroxidation (MDA), proline accumulation, H2O2 accumulation and the activities of major antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT and ascorbate peroxidase, APX) activity grapevine rootstocks of 41B (V. Vinifera × V. Berlandieri) and 1103P (V. Berlandieri × V. Rupestris). Applied Si counteracted the deleterious effects of salinity and boron toxicity on shoot growth by lowering the accumulation of Na in 1103P, and B and Cl in the both rootstocks. Stomatal resistance, MDA, and the concentrations of H2O2 and proline were higher in the plants grown in conditions of B toxicity, salinity and their combination while applied Si lowered these parameters. Lowering SOD and CAT but increasing APX, Si treatment significantly affected the enzyme activities of both rootstocks. Based on the present work, it can be concluded that Si alleviates the adverse effects of salinity, B toxicity and combined salinity-B toxicity on grapevine rootstocks by preventing both oxidative membrane damage and translocation of Na and B from root to shoots and/or soil to plant, and also lowering the phytotoxic effects of Na and B within plant tissues. When considering the antioxidative response and membrane systems, it was concluded that the rootstock 1103P was responsive to Si under stress conditions. To our knowledge, this is the first report that Si improves the combined salt and B tolerance of grapevine grown under saline, B toxic, and B toxic and saline conditions which describes membrane related parameters and antioxidant responses.  相似文献   
85.
Five species of flea beetles (Coleoptera: Chrysomelidae) were recorded for the first time in Turkey:Dibolia numidica Doguet,Longitarsus corynthius corynthius (Reiche et Saulcy),L. onosomae (Peyerimhoff),L. pulmonariae Weise andPhyllotreta ganglbaueri Heikertinger. The zoogeographical distribution of the species was reviewed. Among the species,L. onosmae andD. numidica have a limited distribution area in North Africa, and therefore their presence in Turkey is interesting. http://www.phytoparasitica.org posting July 14, 2004.  相似文献   
86.
Knowledge about the extent of genetic diversity/relatedness in mango germplasm is vital for developing coherent strategies for future gains in productivity. The genetic diversity/relatedness among mango cultivars/genotypes developed in Pakistan has not been investigated previously. We have assessed the genetic diversity among 25 mango genotypes/cultivars using randomly amplified polymorphic DNA (RAPD). Sixty random ten-mer primers were surveyed, out of which 45 yielded amplicons in all the genotypes. Genetic similarity between genotypes/cultivars was in the range of 64–89% with an average of 74%. Similarly, the genetic relatedness among all variants derived from a mango cultivar Chaunsa was in the range of 81.18–88.63%. These coefficients were utilized to construct a dendrogram using the unweighted pair group of arithmetic means (UPGMA). The genotypes were grouped into three (A, B, C) clusters. Generally, genotypes originating from Pakistan were grouped in cluster ‘A’ while cluster ‘B’ primarily composed of southern India as well as Florida cultivars. Kensington Pride was the most distantly related genotype which grouped with Maya and Yakta, forming a distinct cluster ‘C’.  相似文献   
87.
Japanese encephalitis (JE) is vector-borne zoonotic disease which causes encephalitis in humans and horses. Clinical signs for Japanese encephalitis virus (JEV) infection are not clearly evident in the majority of affected animals. In Malaysia, information on the prevalence of JEV infection has not been established. Thus, a cross-sectional study was conducted during two periods, December 2015 to January 2016 and March to August in 2016, to determine the prevalence and risk factors in JEV infections among animals and birds in Peninsular Malaysia. Serum samples were harvested from the 416 samples which were collected from the dogs, cats, water birds, village chicken, jungle fowls, long-tailed macaques, domestic pigs, and cattle in the states of Selangor, Perak, Perlis, Kelantan, and Pahang. The serum samples were screened for JEV antibodies by commercial IgG ELISA kits. A questionnaire was also distributed to obtain information on the animals, birds, and the environmental factors of sampling areas. The results showed that dogs had the highest seropositive rate of 80% (95% CI: ±?11.69) followed by pigs at 44.4% (95% CI: ±?1.715), cattle at 32.2% (95% CI: ±?1.058), birds at 28.9% (95% CI: ±?5.757), cats at 15.6% (95% CI: ±?7.38), and monkeys at 14.3% (95% CI: ±?1.882). The study also showed that JEV seropositivity was high in young animals and in areas where mosquito vectors and migrating birds were prevalent.  相似文献   
88.
In some viticulture regions of the world, high temperature and irradiance can negatively affect the grapevine growth and grape quality. Particle film technology is a remarkable tool, leading to decrease in environmental stress conditions for grape production. In current study, leaf removal and kaolin particle film treatments were performed on east and west sides of grapevine’s canopy of cv. Muscat Hamburg and five different treatments were respectively evaluated: Control (C), leaf removal treatment from east side of grapevine’s canopy (LR-E), leaf removal treatment from east side of grapevine’s canopy plus kaolin particle film treatment (LR-E + K), leaf removal treatment from west side of grapevine’s canopy (LR-W), leaf removal treatment from west side of grapevine’s canopy plus kaolin particle film treatment (LR-W + K). In present research, the higher total phenolic compounds contents were measured in LR-W (2010.56?mg GAE/kg fw), LR-W + K (2006.42?mg GAE/kg fw), LR-E (1925.58?mg GAE/kg fw), LR-E + K (1913.15?mg GAE/kg fw) and C treatment (1851.46?mg GAE/kg fw). Furthermore, means of higher total anthocyanin content were obtained from LR-W (737.68?mg GAE/kg fw), LR-W + K (736.16?mg GAE/kg fw), LR-E (706.50?mg GAE/kg fw), LR-E + K (701.94?mg GAE/kg fw) and C treatment (679.12?mg GAE/kg fw). Consequently, it was observed that both LR-W and LR-W + K treatments had especially advantages in terms of increasing grape quality attributes of cv. Muscat Hamburg; were followed by LR-E and LR-E + K treatments.  相似文献   
89.
Uneven grape ripening, leading to decreases economic valued of grapes is one of the main problems faced by grape growers in early table grape growing. In recent years, there has been increasing concern about improving of fruit quality in fruit crops. Among the various quality improvement methods, different types of foliar compounds are used for this purpose and hydrogen peroxide (H2O2) and phenylalanine (Phe) can be given as examples to some of these chemicals. This research was carried out during the 2015 growing season by using early ripening table grape cv. Trakya Ilkeren. In the study, it was assessed that how different doses of hydrogen peroxide (0, 10, 20 and 40?mM) and phenylalanine (0, 1, 2 and 4?mM) affected physical and biochemical properties of cv. Trakya Ilkeren. In terms of physical properties, doses of hydrogen peroxide and phenylalanine had only significant effects on grape firmness and cluster length. The best results were obtained from 4?mM Phe application (6.76?N) in grape firmness and were obtained from applications of 10, 20 and 40?mM H2O2 (23.66, 23.86 and 23.99?cm) and applications of 1, 2, and 4?mM Phe (23.95, 24.46 and 24.88?cm) in cluster length. However, most of biochemical properties were considerably affected by doses of hydrogen peroxide and phenylalanine except for juice pH and p-value. It was recorded that the highest total phenolic compounds contents varied from 3571.28 (10?mM H2O2) to 3871.22?mg GAE kg?1 fw (40?mM H2O2) compared to 0?mM application (2591.48?mg GAE kg?1 fw). In terms of total anthocyanin content, the highest mean was recorded for 4?mM Phe application (330.56?mg GAE kg?1 fw) than 0?mM application (168.79?mg GAE kg?1 fw). As a result, 4?mM Phe application particularly improved the most of biochemical properties in cv. Trakya Ilkeren.  相似文献   
90.
Demir Kok 《Erwerbs-Obstbau》2018,60(3):253-259
Uneven skin coloration of early ripening table grapes is characterized by a lack of coloring berries within a cluster and the failure of some berries to develop color even with an uncertain delay of harvest. Biostimulants and plant growth regulators are known to have considerable roles on skin color development in the course of grape maturation. This study was carried out to compare the effects of different biostimulant doses, including 0, 1000, 2000 and 4000?ppm (BSt 0, BSt 1, BSt 2 and BSt 4, respectively) with or without gibberellic acid (GA3; 20?ppm) on grape characteristics and chemical composition of early ripening cv. Cardinal grape. Study results of cv. Cardinal grape revealed that alone effects of biostimulant doses had more effective on grape characteristics, total anthocyanin content and total phenolic compounds content from phytochemical characteristics. Although different foliar spray applications had varying effects on physical and chemical parameters; BSt 2 application had especially more superior effects on grape growth and phytochemical characteristics of cv. Cardinal grape.  相似文献   
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