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81.
Membrane damage caused by the non-specific fungal toxin fusaric acid was less on pretreated than on control leaves when tobacco leaves were pretreated with anti-senescence plant hormones, such as kinetin, benzyladenine or the anti-ozonant N-[2-(2-oxo-1-imidazolidinyl)]ethyl-N'-phenylurea. Similarly, the necrosis caused by mercuric chloride was reduced by the above anti-senescence agents. In addition, in in vitro tests, leaves from selected paraquat-tolerant tobacco plants were less sensitive to Alternaria alternata (Fr) Keissler infection than those of the control paraquat-sensitive tobacco leaves. Paraquat-tolerant Conyza canadensis (L) Cronq weeds naturally selected in vineyards in Hungary showed similar inhibition of senescence to paraquat-tolerant tobacco, expressed as more green leaves and slower development. In accordance with this, the paraquat-tolerant Conyza leaves remained almost symptomless, while paraquat-sensitive plants showed severe symptoms after infection with Botrytis cinerea Pers. Oxidative burst (accumulation of hydrogen peroxide) was attenuated in TMV-infected leaves of Xanthi-nc tobacco as a result of treatment with salicylic acid or in leaves where systemic acquired resistance (SAR) had been induced by a previous TMV infection. Accordingly, superoxide dismutase (SOD) activity was higher in Xanthi tobacco leaves with SAR than without SAR. However, in NahG tobacco, in which SAR cannot develop, there was no augmentation of SOD activity. All the above data support the significance of delayed senescence and antioxidants in the resistance of plants to biotic and abiotic necrosis-inducing agents. 相似文献
82.
Gradually increased radiation doses were applied directly to the ovaries of laparotomized ewes. The effect of these doses was studied as exerted on the qualitative and quantitative changes in the follicular apparatus of the ovaries and adenohypophysis of ewes in anoestrus and upon the recovery processes later on after irradiation. The ovaries irradiated with the dose of 4.79 Gy were found to be heavier when examined after some time from irradiation. The 10th and 30th day from irradiation the number of tertiary follicles decreased, the 100th day from irradiation their number increased to a four-fold level, as compared with the 10th day. Adenohypophysis showed a gradual growth of the number of PAS-positive cells. After the irradiation of ovaries with the dose of 9.57 Gy the ovaries showed the lowest rate of damage on the 10th day from irradiation; the 30th and 100th day from irradiation all the present tertiary follicles were in the state of atresia. In comparison with the control group, the amount of gonadotropic cells of adenohypophysis gradually increased, recovering from a rapid drop after irradiation. When the ovaries were irradiated with the dose of 19.14 Gy, all the tertiary follicles were in the state of atresia and the number of PAS-positive cells of adenohypophysis was lower in comparison with the control group. 相似文献
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85.
Tibor Hartel Nora Fagerholm Mario Torralba Ágnes Balázsi Tobias Plieninger 《Strength and Conditioning Journal》2018,71(5):536-544
Rangelands in Europe are imprinted by livestock production and embedded in mosaic landscapes of grasslands, croplands, woodlands, and settlements. They developed as social-ecological systems: People managed rangelands in order to maintain or enhance their ecosystem services, which in turn supported their well-being. The appreciation of ecosystem services provided by rangelands depends on the broad, socioeconomic aspirations and abilities of the managers and the capital available to achieve these aspirations. Here we propose four archetypical social-ecological system representations for European rangelands along the dimensions of socioeconomic aspirations (i.e., oriented toward conventional or sustainable production) and available financial capital (i.e., low or high) to employ farming technologies on rangelands. The four archetypes are aspiration misfit, pockets of sustainability, techno-dependence, and money dependent sustainability. We describe the landscape physiognomy, ecosystem service appreciation, and management-related synergies and trade-offs in ecosystem services supply related to each archetype and formulate a number of research questions to document and further understand them as social-ecological systems. We include the importance of urbanization, land grabbing, and institutional networks in shaping the social-ecological archetypes of rangelands and the relationship between our social-ecological archetypes and the resilience and transformability of rangelands. 相似文献
86.
The interior forest of protected area(PA)recover quickly in terms of greater diversity and structural complexity than peripheral and outsides, which may be due to high plant-frugivore interactions in the interior forest than the disturbed outsides. To describe the structural and functional differences in tree communities from interior to outside forests with in small PA, we quantitatively analyzed the vegetation of Trishna Wildlife Sanctuary, a rich primate habitat of Northeast India. Vegetation was sampled at C10 cm girth at breast height by 10 m 9 500 m sized20 line transects(10 ha) laid in the interior(N = 7),peripheral(N = 7) and outside(N = 6) zones of this sanctuary. All transects were ordinated by Principal Component Analysis based on correlation between diversity and existing disturbance indices. We found significant differences(P \ 0.05) in taxonomic richness and diversity indices between the habitat. Van diagram confirmed greater unique species richness in the interior zone(64) than peripheral(28) and outside(6) zones. Overall density(ha-1) did not differed across the zones, but basal area(m2ha-1) was significantly(P \ 0.01) high in peripheral zone. Vertical distribution of stem density was linearly declined across zones(r2adj[ 0.70; P \ 0.01) with increase in the canopy height. Horizontal distribution of adult stems showed significant inverse quadratic relationship(r2adj[ 0.80; P \ 0.001), which suggests very low density of canopy forming voluminous trees in the interior zone.Immediate protection, restoration and management of interior regions are required to preserve local plant genetic diversity and also to maintain suitable habitat for threatened wildlife. 相似文献
87.
Illés Gábor Sutikno Sigit Szatmári Gábor Sandhyavitri Ari Pásztor László Kristijono Agus Molnár Gábor Yusa Muhamad Székely Balázs 《Journal of Soils and Sediments》2019,19(11):3663-3678
Journal of Soils and Sediments - We conducted this project to develop a feasible method for mapping tropical peat lands of Bengkalis Island—as a test site—in Indonesia. The method based... 相似文献
88.
Sipos Péter Tóth Adrienn Kis Viktória Kovács Balázs Réka Kovács Ivett Németh Tibor 《Journal of Soils and Sediments》2019,19(4):1775-1787
Journal of Soils and Sediments - Heterogeneity of soil mineral particles may lead to the misinterpretation of bulk sorption data on their role in metal sorption, which may be resolved through the... 相似文献
89.
Biswanath Dari Debjani Sihi Santanu Kumar Bal Sanju Kunwar 《Paddy and Water Environment》2017,15(2):395-401
Rice (Oryza sativa L.) is the most important staple food crop in the southern region of Asia, and Indian subcontinent being one of the major producers. Production of conventional transplanted rice requires a large amount of irrigation water, labor, and energy. The scarcity of irrigation water has encouraged farmers to adopt an alternative rice production system, i.e. the direct-seeded rice (DSR), which is proposed to be farmers’ friendly with a potential to save water. Our study reports the performance of DSR with respect to yield and water expense efficiency based on different irrigation regimes and dates of sowing. A field experiment was conducted in the semi-arid region of northern India during the rainy season of 2011 with two treatment combinations (dates of sowing: 15th May and 5th June and three irrigation regimes: irrigation scheduled at irrigation water-to-cumulative potential evapotranspiration; IW/CPE ratio of 1.0, 1.5 and 2.0) in a completely randomized design. We found statistically higher water expense efficiency of DSR sown on 5th June as compared to DSR sown on 15th May without any significant differences in growth and yield. A significant yield difference between DSR grown with irrigation regimes of IW/CPE 1.0 and 1.5 and DSR grown with irrigation regimes of IW/CPE ratio 2.0 were observed. The DSR grown with irrigation regimes of IW/CPE ratio of 1.5 resulted in significantly higher water expense efficiency than the one with IW/CPE ratio of 2.0. Obtaining a higher yield of DSR under scarce irrigation water might be a trade-off between optimum water use and maximum yield avoiding excess ground water exploitation in sub-tropical semi-arid regions of India. Our study suggests that sowing time and irrigation regimes are two important aspects of “rice production” to attain “win–win” solution. Thus, strategic and judicial use of irrigation water with management of sowing time could potentially escalate the rice production in water scarce regions of India. 相似文献
90.
Oszvald M Balázs G Tömösközi S Békés F Tamás L 《Journal of agricultural and food chemistry》2011,59(17):9664-9672
The aim of this work was to compare the effects of incorporated wheat storage proteins on the functional properties of rice and wheat flours. The advantage of rice as a base flour compared to wheat is that it does not contain any wheat flour components and, therefore, has no interactive effect between wheat glutenin proteins. The incorporation of individual HMW glutenin subunit proteins (Bx6, Bx7, and By8) in different ratios had significant positive effects on the mixing requirements of both rice and wheat doughs. Reconstitution experiments using two x+y type HMW-GS pairs together with a bacterially expressed LMW-GS have been also carried out in this study. The largest effects of polymer formation and mixing properties of rice flour dough were observed when Bx and By subunits were used in a 1:1 ratio and HMW and LMW glutenin subunits in a 1:3 ratio. However, using the same subunit ratios in wheat as the base flour, these synergistic effects were not observed. 相似文献