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排序方式: 共有212条查询结果,搜索用时 19 毫秒
1.
Robert Jankowiak Piotr Bilański Julita Zając Adrianna Jobczyk Stephen J. Taerum 《Forest Pathology》2023,53(4):e12821
In Poland's pine forests, mistletoe (Viscum album subsp. austriacum) abundance has increased over the past 20 years. This mistletoe infestation has decreased the growth and vigour of Scots pine trees. In this study, we surveyed the culturable fungi from healthy and diseased V. album subsp. austriacum leaves from two stands in Poland. In total, 63 distinct species were identified, 99.8% of which belonged to the phylum Ascomycota. The community compositions of fungi in mistletoe leaves were similar in healthy and diseased leaves as Alternaria alternata, Aureobasidium pullulans, Botryosphaeria visci, Fusarium paeoniae and Microsphaeropsis olivacea were consistently found in leaves of all symptom types. The most frequently isolated fungus from asymptomatic leaves was M. olivacea, followed by A. alternata, A. pullulans and Hypoxylon rubiginosum. In comparison, the most frequently isolated fungi from leaves with rusty-brown necrotic spots were (in decreasing order) M. olivacea, B. visci, F. paeoniae and A. alternata, while the most frequently isolated fungi from leaves with black or dark brown spots were M. olivacea, A. alternata, A. pullulans, Epicoccum layuense and F. paeoniae. This study was the first comprehensive report showing that certain fungal species may be pathogens of V. album subsp. austriacum in Poland. This study was also the first report of F. paeoniae, F. juglandicola, Diaporthe vacuae and Heterotruncatella spartii from V. album, and the first report of D. vacuae and H. spartii in Poland. 相似文献
2.
Bolesław Porankiewicz Piotr Iskra Jakub Sandak Chiaki Tanaka Karol Jóźwiak 《Wood Science and Technology》2006,40(8):673-682
Dulling of high-speed steel (HSS) cutting tools after milling five wood species has been analyzed. The wood investigated varied in mineral contamination, high-temperature corrosivity (HTC) and density (D). Experiments performed proved that up to date methods for evaluation of mineral contamination in wood should be improved. A new pipe-like form of mineral contamination particles was evidenced. The correlation between the presence of 3D aggregates of silica in wood and high content of K and Ca in the ash was established. Employing multivariable theoretical simulation method, the combined effect of mineral contamination, HTC and wood density on the tool dullness appeared to be a reasonable explanation of the results obtained. 相似文献
3.
Frański R Matławska I Bylka W Sikorska M Fiedorow P Stobiecki M 《Journal of agricultural and food chemistry》2002,50(5):976-982
A series of per-O-methylated flavonoid di- and tri-glycosides, linked with 1-2 and/or 1-6 glycosidic bonds between sugar rings that were isolated from different plant materials were analyzed. It was demonstrated that the fragmentation behavior of permethylated flavonoid glycosides is dependent on the glycosidic bond placement between sugars. Y(n) type fragment ions, created after glycosidic bond cleavage with oxygen retention on sugar at the reducing end for permethylated compounds, were observed in the normal and linked-scan mass spectra recorded for alpha(1-2) bonded conjugates of flavonoid di- and tri-glycosides. Moreover, for alpha (1-6) linked glycosides, Y fragments created after rearrangement and elimination of internal sugar residues were observed in addition to Y(n) type ions, but these fragment ions were not registered in normal desorption ionization spectra. This second type of fragmentation was also reported previously in collision-induced dissociation tandem mass spectrometry (CID MS/MS) spectra of some oligosaccharides and flavonoid glycosides, but their presence was independent of the glycosidic bonds placement between sugar rings. 相似文献
4.
?ukasz?J.??uczajEmail author Ingvar?Svanberg Piotr?K?hler 《Genetic Resources and Crop Evolution》2011,58(5):783-793
The aim of this article is to study the geographical distribution and historical patterns of use of a little known root crop
native to Europe—marsh woundwort Stachys palustris L. The species grows in wet grasslands and arable fields. It produces edible tubers. Both ethnographic literature and archival
sources were searched. Seventeen reliable references concerning the consumption of S. palustris in southern and south–eastern Poland were found. The tubers were usually dried and powdered, and then added to soups or to
bread dough. They were also eaten as raw snacks. The plant was used mainly during food shortages in spring, until the turn
of the nineteenth and twentieth century, and later only as an occasional raw snack until the 1970s. Marsh woundwort was also
eaten in western Ukraine (one reference). There are many references to the edibility of marsh woundwort in the eighteenth
and nineteenth century European economic botany literature, particularly in Sweden and Great Britain. These publications tried
to popularize the use of S. palustris as food. However, there is no firm evidence from these countries that marsh woundwort was used as food there. Marsh woundwort
was also used, throughout northern and central Europe, as pig fodder and as a medicinal plant, particularly for healing wounds.
Further studies on the nutritive value of this forgotten crop should be undertaken, particularly that there is little knowledge
of the chemical composition of both marsh woundwort and its Asian relative Stachys affinis widely cultivated in China as a vegetable. 相似文献
5.
Jacek Piotr Twardowski Michał Hurej Iwona Gruss 《Archives of Agronomy and Soil Science》2016,62(8):1158-1168
The monoculture cropping system causes significant changes within the soil ecosystem, which constitutes a habitat for soil-dwelling springtails. Focusing on the response of soil fauna to 90 years of potato cultivation in monoculture the study investigates the abundance and diversity of soil-dwelling springtails, considering changes in the soil environment in relation to five-crop rotation. Another point was the soil quality evaluation using Collembola as bioindicators (QBS-c index). A long-term monoculture experiment was established in Poland in 1923 and has continued uninterruptedly to the present time. Soil samples were taken over a period of three years (2011–2013) to determine collembolan abundance and composition, as well as physical and chemical soil properties.
The study demonstrated that there were greater numbers of Collembola in the long-term monoculture of potatoes, especially before planting time, compared to numbers in a five-field crop rotation. At the same time apparently greater species diversity was found in potato culture within crop rotation. The biological indicator of soil quality based on the occurrence of springtails (QBS-c) has proved useful in assessing changes in soil caused by agrotechnical activities. This index indicated better biological soil quality in the five-field rotation system compared to monoculture. 相似文献
6.
Influence of the soil properties and human activity on the hysteresis of the moisture retention function in organic soils The hysteresis of the moisture retention function is characterized by the greatest difference of water content during drying and wetting (ΘAΘB) at the same suction. It diminishes by an increased degree of peat decomposition, ash content, bulk density and pH and increases with the volume of macropores (Ø > 50 μm). In the soil suction range Ψ = –1 to –6 kPa the hysteresis can be calculated by multiple regression equations (Tab. 3). Under arable land compared with grassland the hysteresis increases depending on the soil looseness and diminution of soil aggregates. A sand cover on peatland leads in the upper (20–30 cm) layer to a diminution of hysteresis proportional to the sand thickness. 相似文献
7.
Bałczewski P Bachowska B Białas T Biczak R Wieczorek WM Balińska A 《Journal of agricultural and food chemistry》2007,55(5):1881-1892
The aim of this work was to synthesize chiral ionic liquids as chiral solvents for organic synthesis and to evaluate the phyto(eco)toxicity of the new products and starting N-alkylimidazoles and their potential environmental influence on soil and plants. Chiral ionic liquids containing anions such as Cl-, Br-, TsO-, PF6(-), NO3(-), CF3SO3(-), and (+)- and (-)-C6H5CH(OH)C(O)O- were synthesized using (-)-(1R)-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-ethyl [(-)-(1R)-nopyl] halides (X = Cl, Br) and tosylate in 62-100% yields. The chloride 7 and the nitrate 13 ionic liquids possessed a toxicity dependent on the applied concentration. The lowest concentration causing a distinct reduction in plant germination/growth was 100 mg/kg. Spring barley better tolerated the ionic liquids (200 mg/kg) than common radish (100 mg/kg). The nitrate liquid did not exhibit an inhibiting effect on the germination ability of seeds. The starting N-methylimidazole used in lower concentrations (1 and 10 mg/kg of soil dry weight) was not phytotoxic, in contrast to higher doses (>1000 mg/kg). 相似文献
8.
Joanna Mucha Andrzej M. Jagodziński Bartosz Bułaj Piotr Łakomy Adrian M. Talaśka Jacek Oleksyn Marcin Zadworny 《Annals of Forest Science》2018,75(1):22
Key message
Quercus robur seedling mass was affected more by planting density than by taproot pruning. Root pruning enhanced stem biomass at the expense of roots in later growth stages. Alteration of biomass allocation due to nursery practices may result in greater susceptibility to injury and death of the seedlings under unfavorable environmental conditions.Context
Plants adjust their growth and modulate the resource allocation in response to applied treatments and environmental conditions.Aims
The aim was to examine how taproot pruning in seedlings grown at different densities affected long-term growth of Quercus robur.Methods
Seedlings, sown as acorns at two planting densities, with or without pruned roots were harvested in the second, fourth, and fifth years of growth. The effect of root pruning on biomass allocation was determined by measuring leaf, stem, and root mass fractions; carbohydrate concentrations in the roots; and C/N ratios. Specific leaf area and root length were also determined to assess morphological adaptations to growth conditions.Results
Total seedling mass was affected more by planting density than by taproot pruning. After 4 years of growth, root mass fractions were lower and stem mass fractions were greater in seedlings planted at a higher density. Five-year old root-pruned seedlings also had a lower root mass fraction and higher stem mass fractions than unpruned seedlings. Specific root length was not affected by root pruning or planting density.Conclusion
Decrease of relative root biomass with simultaneous increase of stem biomass may be a long-term consequence of taproot pruning of Q. robur, and the effects may manifest years after the seedling stage.9.
10.
Piotr Hulisz Przemysław Charzyński Andrzej Greinert 《Journal of Soils and Sediments》2018,18(2):358-372