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71.
The 541 × Ot1-3 intercross population and bulked segregant analysis (BSA) were used to search for molecular markers linked to genes underlying sprouting and alpha-amylase activity. Six RAPD markers showing association with studied traits were tested for their potential effectiveness in selecting sprouting resistant genotypes. It was shown that although individual effects of markers were not high, their accumulation in one genotype gives substantial increase in sprouting resistance. 相似文献
72.
Summary Fruit size is one of the most important characteristics of highly productive strawberry cultivars. The aim of the experiments was to establish the factors responsible for the expression of this trait. The total yield of large fruits correlates closely with the total yield of all fruits and depends mainly on the mean fruit weight of all fruits. The position of fruits on the inflorescence influences the decline of fruit size to a larger extent in small-fruited clones than in the large-fruited ones. The size of the fruit is controlled by the dimension of the receptacle and number of achenes. The stimulating effects of achenes are quite different in various genotypes and the fruit weight per achene declines with the inferior blossom position. The large-fruited clones have bigger leaves, a larger photosynthetic area, and thicker petioles and flower stalks. Their cells are larger, which is common for the giant genotypes. The results suggest that there exists a possibility for indirect selection of fruit size on the basis of some additional parameters, which can be useful particularily in the years of unsuitable weather conditions. 相似文献
73.
Highly inbred B line of cucumber was used to compare the effect of four types of in vitro culture on somaclonal variation. The plants were regenerated from the following types of culture: twelve- and eighteen-month-old
liquid culture of meristematic clumps (LMC12(18)), ten-month-old embryogenic cytokinin-dependent suspension (CDS), eighteen-month-old embryogenic cytokinin-dependent suspension
in medium with modified NH+
4/NO3
- ratio (CDS 1.7), twelve-month-old embryogenic auxin-dependent suspension (ADS), thirty six-month-old embryogenic auxin-dependent
suspension in medium with modified NH+
4/NO3
- ratio (ADS 1.7) and recurrent leaf callus regeneration (RLC) – repeated 5 times. The differences in the incidence of the
following properties were observed: the ploidy of R0 plants, the segregation of new morphological traits in R1 and the germination ability of R1 seeds. R1 families with the segregation of new phenotypes were most numerous in CDS (62.5%) and LMC18 (57.9%), next in CDS1.7 (35.7%), while the smallest number was found in LMC12 (11.1%) and RLC (3.4%).Tetraploid and mixoploid plants occurred in ADS1.7 and ADS (100%) whereas CDS and RLC were observed
to contain only tetraploids, respectively 33.3% and 55.2%. There were no changes of ploidy after LMC12, LMC18 and CDS1.7. Among new phenotypes there were such that have not been described so far in cucumber: ginkgolike leaf (gll),
yellow-green chlorophyll mutants (y-gc), serrate margin of corolla in male and female flowers (smc).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
74.
PPR‐B‐31: a new maintainer allele in the male‐fertility restorer gene of radish (Raphanus sativus) Ogura cytoplasm 下载免费PDF全文
Anna Hawliczek‐Strulak Grzegorz Bartoszewski Renata Słomnicka Aleksandra Korzeniewska Régine Delourme Iwona Bartkowiak‐Broda Katarzyna Niemirowicz‐Szczytt 《Plant Breeding》2015,134(5):557-563
The PPR‐B gene is responsible for male‐fertility restoration of the Ogura‐type male‐sterile radish plants, and it is located in the complex Rfo locus in the vicinity of similar PPR‐A gene and PPR‐C pseudogene. The aim of this study was to identify PPR‐B alleles and understand the structure of the Rfo locus in radish breeding lines. Five lines of radish with normal male‐fertile cytoplasm were tested. The entire PPR‐B gene was amplified, sequenced and allelic PPR‐B sequences were identified. The results indicated that the maintainer lines 7, 15 and 21 contained a non‐restoring form of PPR‐B protein. A unique PPR‐B was found in lines 24/15 and 31 that are restorer and maintainer lines, respectively. The substitutions might be responsible for the loss of a restoring function of the PPR‐B‐31 allele. Amplification of the PPR‐A/PPR‐B and PPR‐B/PPR‐C intergenic regions allowed to identify rearrangements within Rfo locus. Obtained results confirm the wide allelic variation within the Rfo locus, as well as high genetic complexity of the fertility restoration mechanism in radish. 相似文献
75.
Przemysław Barłóg 《Journal of plant nutrition》2016,39(1):1-16
High yield of sugar beet require adequate mineral nutrition. To be diagnosed across interacting nutrients using appropriate interpretation models, the plant must be sampled at a critical physiological stage. This study aimed to develop and validate norms at the 7-leaf and well-developed rosette stages, for diagnostic purposes using the Diagnosis and Recommended Integrated System (DRIS) and Compositional Nutrient Diagnosis based on centered log ratios (CND-clr). Data on nutrient concentrations and plant performance were obtained from 409 plots in West-Central Poland. With respect to the growth stages, for physiological and practical reasons, the 7-leaf stage is preferable for diagnostic purposes. At this growth stage, the high-yield subpopulation characterized by higher concentration of potassium and sodium compared to other nutrients. CND-clr indices were closely related to DRIS indices (R2 > 0.93). The CND-clr indices, however, better explained the differences in the white sugar yield within the validated dataset than the DRIS indices. 相似文献
76.
Krystyna Grodzińvska 《Water, air, and soil pollution》1978,9(1):83-97
The concentrations of heavy metals (Cd, Co, Cr, Ni, Cu, Ph, Zn, Mn, Fe) and other elements (Mg, Na, K, Ca) were determined in the samples of Pleurozium schreberi and Hylocomium splendens from 12 Polish national parks. The significant differences in the concentrations of all heavy metals between particular parks were found. The lowest concentrations of these metals were recorded in the mosses from the national parks in northern Poland, the highest in southern Poland. Significant differences in the heavy metals contents of the mosses between central and peripheral park areas, between green and brown parts of mosses, as well as between moss species were also found. 相似文献
77.
Krzaklewski W. Barszcz J. Małek S. kozioł K. Pietrzykowski M. 《Water, air, and soil pollution》2004,159(1):151-164
In the technological processes of ore flotation in the non-ferrous metal industry flotation, tailings constitute up to 98% of the total of the processed material. They are stored in sedimentation ponds as fine-grained drift containing an excess of heavy metals, mainly zinc, cadmium, lead and copper. After the dehydration and drying up of the surface of sedimentation ponds, these metals are carried with dust by the wind and they are accumulated in the vicinity of the ponds in humus horizons of soils causing considerable degradation and even devastation. In this publication, we have presented the results of research on the negative influence of such a structure on the soils of an adjacent fragment of forest and its dependence on the distance from the sedimentation pond. The level of degradation of the soils under research has been assessed on the basis of changes and transformations of the morphological soil profiles, the level of alkalization and accumulation of heavy metals (Zn, Pb, Cd) in the topsoil layers and their translocation in the soil horizons. The following soils have been distinguished in the investigated area: Haplic Podzols distorted and degraded as well as Urbic Anthrosols. The acquired results have served to depict the spatial accumulation of these heavy metals in the topsoil layers. The highest accumulation of heavy metals and the degradation of the forest sites connected with it has occurred in the vicinity of a sedimentation pond drain channel. Soil remediation has been recommended in this area. 相似文献
78.
Whole cell fatty acid (WCFA) compositions of three different structures of ectomycorrhizal (ECM) fungi: sporocarps, pure culture mycelia and ectomycorrhizas were analysed to evaluate the potential use of fatty acid profiles as biomarkers for ECM fungi and ectomycorrhiza-associated bacteria. Sporocarps of Amanita muscaria, Amanita rubescens, Lactarius rufus, Lactarius thejogalus, Leccinum scabrum, Paxillus involutus, Russula foetens, Russula rosea, Russula vesca, Suillus grevillei, Tylopilus felleus, Xerocomus badius, Xerocomus subtomentosus, pure cultures of A. muscaria, P. involutus, X. badius, X. subtomentosus, Suillus bovinus Suillus luteus and seven ectomycorrhizal morphotypes of Norway spruce were examined. Our results revealed species-specific composition of fatty acids of fungal sporocarps and pure culture mycelia. Ectomycorrhizal morphotypes distinguished and identified by morphological and molecular methods (PCR-RLFP and sequencing) created specific fatty acid profiles. The dominating fatty acids in pure cultures and sporocarps were 18:2ω6,9, 18:1ω9 and 16:0, whereas ectomycorrhizas also contained plant and bacterial specific fatty acids. Especially, fatty acids specific to Gram-positive bacteria 15:0 anteiso and 17:0 anteiso were present in relatively high amounts and suggested that these bacteria are dominating in the examined Norway spruce mycorrhizosphere. In conclusion, our results show that fatty acid based methods can be useful in studies of ectomycorrhizal fungi, both as a quick method for differentiation of fungal species and also in studies of mycorrhiza-associated microorganisms in the field. 相似文献
79.
H. Gibb R.B. Pettersson J. Hilszczański J.P. Ball O. Atlegrim 《Biological conservation》2006,129(4):437-450
New conservation-oriented forestry aims to maintain intact populations of forest organisms by improving the conservation value of managed forests and providing protected areas. We tested the conservation value of treatments of dead wood for assemblages of early successional saproxylic beetles. In nine areas in northern Sweden, we selected one clear-cut, one mature managed forest and one reserve. In 2001-2002, we placed three blocks of spruce logs, each containing control, burned and shaded logs and a high stump (“snag”) at each site. Saproxylic beetles emerging from the dead wood were collected using emergence traps and beetles flying close to it were collected using flight-intercept traps. After one year of exposure, assemblage composition was examined, with respect to nutritionally-defined functional groups, red-listed species and fire-favoured species. Experimental snags were most complementary to control logs, supporting different assemblages of cambium consumers and fungivores and supporting more red-listed individuals. Burned logs supported depauperate assemblages, particularly with respect to cambium consumers, while shading of logs affected assemblages of fungivores, but only on clear-cuts. Despite containing less dead wood, managed forests provided valuable habitat, supporting similar assemblages of saproxylic beetles to reserves. Most functional groups were less abundant on clear-cuts than in older forests, but fire-favoured species were more common on clear-cuts, suggesting that clear-cuts may support assemblages of species associated with natural disturbances, if suitable substrates are available. Utilization of logs by saproxylic beetles changes over time, so long-term monitoring of our experimental logs will determine their lifetime conservation value. 相似文献
80.
Bogumił Rychcik Jadwiga Wierzbowska Milena Kaźmierczak-Pietkiewicz Arkadiusz Światły 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(4):349-359
ABSTRACTThe content of macronutrients in potato tubers arouses interest because of their substantial consumption in the world and significant role in elements' budget in human diet. The research objective has been to evaluate the content of macronutrients in tubers of potatoes grown in different systems of crop production in Poland. In 2012–2014, an experiment was conducted to test potato cultivation in three-crop production systems: conventional, integrated and organic. In each of the six-field crop rotation systems, there were five potato cultivars classified into different earliness groups. The following macronutrients in dry mass of potato tubers were determined: N, P, K, Ca, Mg, Na, S and Cl, and the various ratios between them were calculated. The research carried out proved that potatoes production systems affect the chemical composition of tubers, which is additionally modified by whether condition and genetic features of cultivars. Potato tubers from organic farming contained by about 20% less N than tubers from conventional or integrated systems. Potato tubers from organic production system displayed lower content of Ca and Na in comparison with the conventional and integrated systems. The least of P and S were detected in tubers of the potatoes grown conventionally. 相似文献