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91.
Abrar Muhammad Mohsin Xu Hu Aziz Tariq Sun Nan Mustafa Adnan Aslam Muhammad Wajahat Shah Syed Atizaz Ali Mehmood Khalid Zhou Baoku Ma Xingzhu Chen Xianni Xu Minggang 《Journal of Soils and Sediments》2021,21(2):705-723
Journal of Soils and Sediments - Soil organic carbon (SOC) is an important parameter determining soil fertility and sustaining soil health. How C, N, and P contents and their stoichiometric ratios... 相似文献
92.
93.
The effects of salinity, density, and nutrient on the growth, reproduction, and ecophysiology of a perennial halophyte, Cressa cretica L., were studied. Lower salinity concentration (425 mM) promoted the growth, but the highest salinity (850 mM) did not have a significant effect. Plants grew faster and were healthier at low density treatment. Lack of nitrogen (N) in the medium substantially inhibited shoot growth. Higher rhizome length and increased dry weight were some of the symptoms of N‐deficiency. Phosphorus (P)‐free plants also showed higher dry weight and higher ratio of rhizomes to shoots. Reproductive capacity of Cressa cretica plants was not affected by the absence of P. Growth and reproduction of Cressa cretica plants were significantly inhibited by potassium (K) deficiency. Optimal plant growth was recorded in complete nutrient solution. Higher concentrations of oxalate were found in plants growing under low density conditions and in non‐saline controls. Proline concentration increased with the increase in salinity of the medium. Chlorophyll a and b synthesis were inhibited by high salinity treatments whereas changes in density regimes did not have an effect. 相似文献
94.
Two trials were conducted with two sizes, grow‐out (80.0 mg b.w.) and fattening (5.0 g b.w.), of Penaeus semisulcatus to compare the production and yield of shrimp cultured at different stocking densities within an indoor running‐seawater system. In the first experiment, postlarvae were cultured at 50, 100, 150 and 200 m?3 for 68 days, while in the second experiment, juveniles were cultured at 24, 50, 74 and 100 m?3 for 126 days. The results of the two experiments showed significant decrease in weight of shrimp as the stocking density increased. During the grow‐out stage, no statistical differences were observed on survival rates among the shrimp stocked at different densities. Thus, as the primary factor to consider at this stage is the number of shrimp produced, it is recommended to use a density of 200 shrimp m?3. During the fattening stage, the survival rate at the highest density was statistically lower than the other three densities. The mean yield was 437.02, 869.16, 1217.62 and 1446.78 g m?3 for shrimp stocked at 24, 50, 74 and 100 m?3 respectively. Although the average harvest size of juveniles at the lowest stocking density was statistically higher than those stocked at the highest stocking density, both sizes (18.12 and 16.67 g) will be classified as one size group in the market, i.e. medium. As the yield significantly increases as the stocking density is increased, it is therefore recommended that the stocking density for the fattening stage be 100 shrimp m?3. 相似文献
95.
Yamin Muhammad bin Wan Ismail Wan Ishak Abd Aziz Samsuzana bin Mohd Kassim Muhamad Saufi Akbar Farah Naz Ibrahim Muhammad 《Precision Agriculture》2022,23(4):1413-1448
Precision Agriculture - This research study focuses on the design of variable rate liquid fertilizer applicator which can measure the NPK status of soil and applies N, P and K nutrients... 相似文献
96.
Genotype×tillage interaction and the performance of winter bread wheat genotypes in temperate and cold dryland conditions
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Ebrahim ROOHI Reza MOHAMMADI Abdoul Aziz NIANE Javad VAFABAKHSH Mozaffar ROUSTAEE Mohammad Reza JALAL KAMALI Shahriar SOHRABI Shahriar FATEHI Hossain TARIMORADI 《农业科学学报》2022,21(11):3199-3215
Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran. 相似文献
97.
Saida Rifai Aziz Fassouane Paulo M. Pinho Anake Kijjoa Nair Nazareth Maria S?o José Nascimento Werner Herz 《Marine drugs》2005,3(1):15-21
Fasciculatin, a furanosesterterpene isolated from the marine sponge Ircinia variabilis from the Atlantic Coast of Morocco, has been evaluated for its influence on a mitogen-induced proliferation of human lymphocytes and growth of human tumor cell lines. 相似文献
98.
Zafer Ulutas Emre Sirin Yüksel Aksoy Aziz Sahin Mehmet Kuran 《Tropical animal health and production》2013,45(4):953-956
The purpose of this study was to estimate the genetic parameters for birth weight of Karayaka lambs by separating direct genetic, maternal genetic, and maternal permanent environmental effects. Records of 1013 Karayaka lambs born between 2005 and 2010 were analyzed. Six different animal models were examined, all including direct additive genetic variance and various combinations of genetic and environmental maternal effects. The most appropriate model was chosen based on log-likelihood ratio tests. Since model 1 had the smallest likelihood value, it was chosen as the best model in this study. Depending on the model, direct heritability varied from 0.37 to 0.55 and maternal heritability ranged from 0.08 to 0.20 for birth weight. 相似文献
99.
Khalid Usman Niamatullah Khan Muhammad Umar Khan Aziz ur Rehman Said Ghulam 《农业科学学报》2013,12(9):1568-1579
Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage (CT) is more productive than zero tillage (ZT)/reduced tillage (RT). Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC (108 g a.i. ha?1), lactofen 24 EC (168 g a.i. ha?1), haloxyfop 10.8 EC + lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I. Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop + lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides × CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides × CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I. Khan. 相似文献
100.
Wood exhibits a pronounced time dependent deformation behavior which is usually split into ‘viscoelastic’ creep at constant
moisture content (MC) and ‘mechano-sorptive’ creep in varying MC conditions. Experimental determination of model rheological
parameters on a material level remains a serious challenge, and diversity of experimental methods makes published results
difficult to compare. In this study, a cantilever experimental setup is proposed for creep tests because of its close analogy
with the mechanical behavior of wood during drying. Creep measurements were conducted at different load levels (LL) under
controlled temperature and humidity conditions. Radial specimens of white spruce wood [Picea glauca (Moench.) Voss.] with dimensions of 110 mm in length (R), 25 mm in width (T), and 7 mm in thickness (L) were used. The influence of LL and MC on creep behavior of wood was exhibited. In constant MC conditions, no significant
difference was observed between creep of tensile and compressive faces of wood cantilever. For load not greater than 50% of
the ultimate load, the material exhibited a linear viscoelastic creep behavior at the three equilibrium moisture contents
considered in the study. The mechano-sorptive creep after the first sorption phase was several times greater than creep at
constant moisture conditions. Experimental data were fitted with numerical simulation of the global rheological model developed
by authors for rheological parameter identification. 相似文献