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141.
One sixth of the world’s population is suffering from hidden hunger that indicates a gross malnutrition particularly among children and women of third world countries. The deficiency of micro nutrients, especially iron (Fe) causes a number of ailments such as megaloblastic anemia and neural tube defects in poor population. There is a dire need to supplement iron in the diet. Current efforts implicate fortification of wheat flour and other grains with different iron formulations such as ethylenediaminetetraacetic acid (EDTA), FeSO4 and elemental iron. However, all such interventions are not sustainable due to logistic and quality assurance problems in resource-limited settings. For a long term solution, development of crop plants with increased micronutrients and iron bioavailability is essential. Therefore, biofortification of cereal grains using translational genomics approaches for enhancement of folate through genome editing in cereals is inevitable to mitigate the folate deficiency in poor remote population in a cost effective manner.  相似文献   
142.
Abstract

One of the problems in obtaining high wheat yield is the unavailability of micronutrients in balanced quantities. Zinc is an essential micronutrient due to its involvement in many metabolic processes in plant. In this experiment, seeds of two wheat cultivars (Faisalabad-2008 and Lasani-2008) were subjected to soak in aerated Zn solution of 0.1 and 0.01?M for 12?hr. For the seed coating, Zn was adhered to the wheat seeds by using Arabic gum by using zinc sulfate (ZnSO4·7H2O) as a source. Untreated dry seeds were considered as a control. Results indicated that field emergence was improved by Zn seed treatments, maximum numbers of seedlings were observed in seed priming with 0.01?M Zn solution. Seed osmoprimed with 0.01?M Zn solution improved the grain yield, biological yield, and other yield related traits. Grain and straw Zn enrichment were also enhanced in seed osmoprimed with 0.01?M Zn solution.  相似文献   
143.
Abstract

Inoculation effect of arbuscular mycorrhizal fungi (AMF) on phosphorus (P) transfer from composted dung of cattle with a diet supplemented with powdered rock phosphate (RP) and their successive uptake by mung bean plants was assessed in alkaline soil. The efficacy of composted RP fed dung alone or/and in combination with AMF inoculums containing six different species were compared with SSP in six replicates per treatment in pots. The results showed that the association of AMF with composted RP fed dung had a positive effect on mung bean shoot (3.04?g) and root (2.62?g) biomass, chlorophyll (a, b), carotenoid contents and N (58.38?mg plant?1) and P (4.61?mg plant?1) uptake. Similarly, the percent roots colonization (56%) and nodulation of mung bean plant roots and their post-harvest soil properties were also improved by the inoculation of AMF together with composted RP fed dung. It is concluded that the combined application of AMF with composted RP fed dung has almost the same effect as SSP for improving mung bean plants growth and their nutrients uptake. Moreover, AMF inoculants can be used as a suitable biofertilizer in combination with locally available organic sources of fertilizers for improving P status and growth of plants in alkaline soils.  相似文献   
144.
Abstract

Canola (Brassica napus L.), is the most important oilseed crop due to high oil contents and low concentration of erucic acid and glucosinolates. In Pakistan, oil seed production is not sufficient to fulfill the needs of the country. Thus, the planned experiment was aimed to evaluate the performance of different canola cultivars i.e. Faisal Canola, Pakola, PARC Canola hybrid and Rainbow at grown under various soil applied boron (B) levels viz., 0, 1, 2?kg ha?1 under a rainfed environment. The experiment was laid out in randomized complete block design with four replications. Among the canola cultivars, the maximum seed oil contents were recorded in cultivar ‘Pakola’ whereas, higher linolenic acid and protein were recorded in cultivar ‘Faisal canola’ as compared to other cultivars. A synergistic effect was found between various levels of B and quality parameters of the canola seed; as higher concentration of oil contents were found when B was applied 2?kg ha?1. Conversely the linolenic acid showed the antagonistic behavior with the various B levels. On the other hand, protein contents, oleic acid and erucic acid revealed non-significant differences under different B application rates. In conclusion, the cultivar ‘Pakola’ provided the highest oil content when the B was applied at 2?kg ha?1; the low concentration of unsaturated fatty acid was observed in ‘PARC canola’ cultivar in the Pothwar region of Punjab, Pakistan.  相似文献   
145.
This study describes the identification of a quantitative trait locus (QTL) in the recombinant inbred line population of ILL2024 × ILL6788 and subsequent validation of associated molecular markers. A high‐quality genetic linkage map was constructed with 758 markers that cover 1,057 cM, with an average intermarker distance of 2 cM. QTL analysis revealed a single genomic region on Lc2 to be associated with B tolerance and accounted for up to 76% of phenotypic variation (Vp). The best markers for B tolerance were assessed for their utility in routine breeding applications using validation panels of diverse lentil germplasm and breeding material derived from ILL2024. A marker generated from the dense genetic map of this study was found to be the most accurate of all markers available for B tolerance in lentil, with a success rate of 93% within a large breeding pool derived from ILL2024. However, given the number of the unrelated lines for which the marker–trait association was not conserved, B tolerance screening is still required at later stages to confirm predicted phenotypes.  相似文献   
146.
Vitamin A deficiency is widely prevailing in children and women of developing countries. Deficiency of vitamin A causes night blindness, growth retardation, xerophthalmia and increases the susceptibility against epidemic diseases. Among different interventions of overcoming malnutrition, biofortification is the most acceptable and preferred intervention among researchers, growers and consumers. Maize is grown and consumed in those regions where vitamin A deficiency is most prevalent; thus, targeting this crop for provitamin A biofortification is the most appropriate solution. Different breeding strategies including diversity analysis, introduction and stability analysis of exotic germplasm, hybridization, heterosis breeding, mutagenesis and marker‐assisted selection are practised for exploring maize germplasm and development of provitamin A‐enriched cultivars. Genome‐wide association selection and development of transgenic maize genotypes are also being practised, whereas RNA interference and genome editing tools could also be used as potential strategies for provitamin A biofortification of maize genotypes. The use of these breeding strategies for provitamin A biofortification of maize is comprehensively reviewed to provide a working outline for maize breeders.  相似文献   
147.
Journal of Crop Science and Biotechnology - Understanding genetic architecture of a crop germplasm is necessary for designing a successful breeding program. Herein, we evaluated a large collection...  相似文献   
148.
Interspecific hybrids between Trifolium uniflorum and cultivated white clover (Trifolium repens) have highly useful characteristics for temperate pastoral systems derived from both parent species. However, the early hybrids (F1 and BC1) also have unacceptably poor seed production for commerce. This study analysed the basis for the poor seed production and investigated breeding strategies for overcoming the problem. The BC1F1 generation produced lower‐than‐expected numbers of heads per plant and seeds per floret. Backcrossing of selected hybrids to white clover corrected these deficiencies and created new variation. Seed numbers were also returned to near target levels by recurrent selection within the BC1 generation. Thus, it was possible to retain a theoretical average of 25% of T. uniflorum genome and still achieve high seed production per plant. The BC1F2 and BC2F1 generations produced high seed numbers per plant, along with reasonable variation. Both of these second‐generation hybrid forms have high reproductive potential and should be the focus for the selection of the desired combinations of agronomic and seed production traits.  相似文献   
149.
不同形态硼对油菜幼苗铝毒的缓解效应及其FTIR特征分析   总被引:1,自引:0,他引:1  
采用水培法,以油菜品种Cao 221167为试验材料,设置无机态硼酸(BA)和有机态山梨醇硼(SB)及不同Al~(3+)(0、100、200和500μmol L~(–1))处理,研究不同形态硼(B)对油菜幼苗铝(Al)毒的缓解作用及不同形态B之间的缓解效应差异,以及利用FTIR(傅里叶红外光谱)技术分析叶片各物质含量的变化。结果表明,Al毒胁迫下,不同形态B(BA和SB)处理,显著提高植株生物量和根系长度(0、100、200和500μmol L~(–1) Al毒胁迫下BA处理根长分别增加了52.15%、101.45%、366.70%和18.73%;SB处理分别增加了46.80%、133.98%、261.36%和10.77%),提高色素含量和SOD活性,而降低了Al含量、MDA含量和POD活性。不同形态B处理下,油菜幼苗在200μmol L~(–1) Al~(3+)处理下长势、生物量及色素含量最高。在500μmol L~(–1) Al~(3+)处理下,油菜幼苗株高、根长、总干鲜重及色素含量显著低于无Al处理;FTIR分析表明,Al毒胁迫下油菜叶片中蛋白质和低聚糖等含量明显上升,加硼明显降低了蛋白质和低聚糖的含量,且BA处理降低幅度明显高于SB处理。说明不同形态B(BA和SB)的添加均明显缓解Al毒,且BA对Al毒缓解效果优于SB,这为农业生产中施用何种硼肥来缓解Al毒起到一定的指导作用。  相似文献   
150.
Wheat is one of the most widely cultivated crops and, being the staple diet of more than 40 countries, it plays an imperative role in food security. Wheat has remarkable genetic potential to synchronize its flowering time with favourable environmental conditions. This ability to time its flowering is a key factor for its global adaptability and enables wheat plant to produce satisfactory grain yield under very diverse temperature and soil moisture conditions. Vernalization (Vrn), photoperiod (Ppd) and earliness per se (Eps) are the three genetic systems controlling flowering time in wheat. The objective of this review is to provide comprehensive information on the physiological, molecular and biological aspects of the three genetic constituents of flowering and maturity time in wheat. Reviews written in the past have covered either one of the aspects; and generally focused on one of the three genetic constituents of the flowering time. The current review provides (a) a detailed overview of all three gene systems (vernalization, photoperiod and earliness per se) controlling flowering time, (b) details of the primer sequences, their annealing temperatures and expected amplicon sizes for all known markers of detecting vernalization and photoperiod alleles, and (c) an up to date list of QTLs affecting flowering and/or maturity time in wheat.  相似文献   
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