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231.
Biochar is obtained by the pyrolysis of biomass, and contains abundant carbon and minerals. Biochar supplementation of soils can greatly improve soil health and quality, but these beneficial effects typically develop slowly over time. Depending on the quality of the biochar and the soil to which it is applied, it may take years before positive effects are apparent. This is because organic substances are slowly sorbed onto the biochar over time, and the biochar eventually becomes part of the sorption complex of the soil. It is therefore advisable to apply biochar together with some organic material. We examined the effect of co-application of different doses of biochar with manure on soil dehydrogenase activity (DHA), soil oxidizable carbon (COX), cumulative soil respiration, soil buffering capacity, the soil exchange reaction (pH/KCl) and the production yield of winter rape seeds. We also determined seed production when artificial granular fertilizers were added to biochar and manure. The results showed that the application of biochar and manure significantly increased grain yield, DHA, the soil exchange reaction and cumulative respiration. Thus, application of biochar with organic material can increase seed yield and some properties of agricultural soils. However, the positive effect of biochar on seed yield was not directly proportional to biochar dose, in that the seed yield was lower for a biochar dose of 45 t/ha than 30 t/ha. 相似文献
232.
The effect of cereal straw with added mineral N fertilization on crop yields, N uptake, total organic C content and hot water soluble C content in topsoil and on the relationships between organic C content in topsoil and organic matter balance was evaluated in a long-term field experiment established in 1966. The effect of straw plus mineral N fertilization was similar to the effect of farmyard manure (FYM) in the dry matter yields and also in the N uptake by plants. The effect of straw and mineral N fertilization on the organic C accumulation in soil was inferior to the effect of farmyard manure. Relationships between organic matter balance and total organic C content in the topsoil was positive and statistically significant. A favourable effect of mineral NPK fertilization on the C sequestration to soil was related to the effect of FYM fertilization. 相似文献
233.
Lubica Pospíšilová Markéta Komínková Ondřej Zítka René Kizek Gabriela Barančíková Tadeáš Litavec 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(6):517-528
Composition of humic acids (HA) is a function of plant-derived inputs, degradation processes regulated by microorganisms, organo-mineral interactions and age. Characterization of different origin humic substances is important for evaluation of their contribution to stabile and labile carbon pool in the environment. The relative abundance of chemical components in HA isolated from soils, compost, commercial lignohumates, alginite, acadiane and lignite was studied with aim to quantify content of important biomarkers such as amino acid, lipids and polyphenols. HA were considered as a heterogeneous complex and high concentration of peptides, polyphenols and lipids was determined in acadian-HA to compare with soil-HA. Compost-HA contained much more amino acids to compare with soil-HA samples. Alginite-HA and lignite-HA were similar in biomarkers content to soil-HA. Fourier transform infrared spectroscopy confirmed that chemical composition and functional groups content differs with the origin, humification degree and the age of studied samples. Soil-HA are typically composed of a variety of ?OH, COOH?, C–O, C–H2, (aliphatic and aromatic) groups, quinines, lignin fragments, polysaccharide, monosaccharide and proteins fragments, which are linked together by ?O?, ?NH?, ?H=, >C=O, metal ions and –S? groups. 13C NMR spectroscopy showed that aromatic carbon content was the highest in lignite-HA and soil-HA. 相似文献
234.
Ana Rivera Daniel Fenero Antoni Almirall Juan José Ferreira Joan Simó Marçal Plans Roser Romero del Castillo Francesc Casañas 《Genetic Resources and Crop Evolution》2013,60(6):1885-1898
Few studies have explored sensory variability in beans. We used geographic, agronomic, morphological, and genetic criteria to select numerous groups of landraces from among the many collected in Catalonia (northeast Spain). Beans cultivated in a single location to avoid environmental effects were submitted to a trained panel for sensory analysis. We used multiple linear regression to explore whether the flavor and texture of the seed (evaluable only by tasting after cooking) can be estimated from easily measurable traits like the appearance of the beans. The degree of variability found for all sensory traits (coefficients of variation: 20–70 %) was similar to that of agronomic traits; however, entries were grouped differently for sensory and agronomic traits, suggesting independent evolution. Negative genotypic correlations between some sensory traits will probably hinder attempts to achieve ideotypes combining low seed-coat perceptibility, low mealiness, and high flavor. Regressions between easily measurable traits (agronomic and culinary traits and appearance of the seeds) and flavor and texture yielded R2 values ranging from 0.47 to 0.64. We consider these values good enough for rough screening of sensory attributes in genetic resources studies or breeding. 相似文献
235.
Lax Paola Rondan Dueñas Juan C. Andrade Alberto J. Doucet Marcelo E. 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(2):397-409
European Journal of Plant Pathology - Trichoderma aggressivum, a mycopathogen causing green mould disease, is a major problem in Agaricus bisporus cultivation due to crop loss, and resistance to... 相似文献
236.
Zusammenfassung Es wurde der Einfluss unterschiedlicher Düngergaben auf den Gehalt an Zitronens?ure in Knollen der Sorte ‘Radka’ geprüft,
wobei die Probennahmen in den Phasen Vollblüte, im Abblühen und der Reife erfolgten.
In reifen Knollen wurde ein relativ hoher Gehalt an Zitronens?ure bei einer Düngung von 120 kg N, 355 kg Ca und 30 kg Mg ha
festgestellt. ?hnliche Ergebnisse wurden auch bei der Variante ohne Magnesium gefunden. Relativ hohe Gehalte an Zitronens?ure
zeigte die Variante mit 60 kg Mg und 120 kg N ha-ohne Kalzium.
Stark verminderte Gehalte an Zitronens?ure in reifen Knollen wurden dagegen bei den Varianten gefunden, die kein Calzium oder
Magnesium erhalten hatten. 相似文献
237.
B. Míča 《Potato Research》1969,12(3):151-156
Zusammenfassung Es wurde festgestellt, dass der Einfluss der Vegetationsjahre auf den N?hrstoffgehalt von Kartoffelknollen statistisch positiv
gesichert erscheint. Zwischen den einzelnen Vegetationsphasen wurden deutliche Unterschiede gefunden. Dagegen liess sich der
Einfluss der Düngung auf den N?hrstoffgehalt der Knollen statistisch nicht absichern. Wird der N?hrstoffentzug auf Knollen
einer Pflanze bezogen, so ist zu beobachten, dass N?hrstoffentnahmen durch Knollen einer Pflanze neben den Gehalten an N?hrstoffen
in der Knolle auch durch die Knollenmasse beeinflusst wird. Die Vegetationsjahre zeigen auch in diesem Falle einen wesentlichen
Einfluss. Die h?chste durchschnittliche Entnahme an Stickstoff, Phosphor und Kalium wurde bei reifenden Knollen beobachtet. 相似文献
238.
Nacira Muñoz Maria Eugenia Soria-Díaz Hamid Manyani Rocío Contreras Sánchez-Matamoros Antonio Gil Serrano Manuel Megías Ramiro Lascano 《Biology and Fertility of Soils》2014,50(2):207-215
The establishment of a symbiotic interaction involves a signal exchange between the host legume (flavonoids) and the nitrogen-fixing rhizobia (nodulation factors (NFs)). Likewise, abiotic stress conditions, such as salinity and drought, strongly reduce the nodulation process, possibly affecting also the signal exchange. In this work we characterized the structure and biological activity of NFs produced by Bradyrhizobium japonicum USDA 138 under control, salt, and osmotic stress conditions. This strain is the most widely used in Argentine soybean culture; under control conditions, it produces a mixture of four types of NFs (V(C16:0,MeFuc), V(C18:1,MeFuc), IV(C18:1), and V(C18:1,Ac,MeFuc)). Interestingly, under stress conditions, this strain produces new types of NFs, one common for both stress conditions (V(C16:1,MeFuc)) and another one only present under salt stress (IV(C18:1,MeFuc)). All mixtures of NFs, extracted from control, salt, and osmotic stress conditions, showed biological activity in soybean plants, such as root hair deformation, and the radical application of purified NFs induced systemic differences in dry matter accumulation. The inoculation of soybean with genistein-induced bacteria cultured under both control and stress conditions had a positive effect on the number of nodules formed and in some cases on dry matter accumulation. These responses are not related to changes in chlorophyll fluorescence or greenness index. 相似文献
239.
de Sá Silvia Ferreira dos Santos Luísa C. Aragão da Conceição Léo D. H. C. Schwartzhaupt Braga Marcelo Fideles Laviola Bruno Galvêas Cardoso Alexandre Nunes Sayd Ricardo Meneses Junqueira Nilton T. Vilela 《Genetic Resources and Crop Evolution》2021,68(8):3193-3204
Genetic Resources and Crop Evolution - Macauba [Acrocomia aculeata (Jacq.) Lodd. ex Mart.], a palm tree native to Brazil, has a high potential as an alternative source for vegetal oil production.... 相似文献
240.
J. Ehrenbergerová N. Březinová Belcredi J. Kopáček L. Melišová P. Hrstková S. Macuchová K. Vaculová I. Paulíčková 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):122-128
Green biomass of young barley plants exhibited statistically significant higher activity of superoxide dismutase (SOD) and
catalase (CAT) at sampling I (in the phase of plant development DC 29) compared to the later sampling II (DC 31). Significant
effects of varieties, years and interactions of the studied factors on the activity of the studied antioxidants were determined.
During the experiment period (2005–2007), the variety Sebastian provided statistically significant higher average SOD activity (486 U.g-1) versus the variety Malz (416 U.g-1 dry matter) and line KM1910 (418 U.g-1 dry matter). No statistically significant difference was recorded between the latter two varieties. Average catalase
activity of the varieties did not show any significant difference. Significantly higher CAT activity in the sampling I was
recorded on average of years and locations in the variety Sebastian and hull-less line KM1910 (935 and 907 U.g-1) compared to the variety Malz (675 U.g-1). We can state that green biomass of young spring barley plants
taken during the growth phase DC 29 was a significant source of enzymes catalase and superoxide dismutase in the course of
the experiment (2005–2007). 相似文献