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1.
Provision of feed supplies for the rapidly growing livestock population is essential in West Asia. Shortages can be alleviated by growing forage crops in the existing fallow lands.
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields. 相似文献
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields. 相似文献
2.
麻类纤维在非织造领域的应用 总被引:2,自引:0,他引:2
本文阐述了麻类纤维在我国非织造行业新用途的开发和拓展,对麻类纤维在非织造领域的利用符合国家农业可持续性发展的方向。 相似文献
3.
4.
13~18周龄笼养蛋鸭适宜蛋白质和蛋氨酸水平的研究 总被引:4,自引:1,他引:3
用 32 4羽满 1 2周龄的金定鸭 ,通过饲养试验、代谢试验、屠宰试验和对试鸭产蛋期 (1 9~ 2 8周龄 )产蛋性能的观察 ,研究了在等能条件下(ME :1 1 51MJ/kg) ,不同蛋白质水平 (CP :1 3 %、 1 5 %、 1 7% )和蛋氨酸水平 (Met/CP :0 0 1 7、 0 0 2 2、 0 0 2 7)组成的 9种饲粮对 1 3~ 1 8周龄笼养蛋鸭的生长性能、养分利用、体成分沉积和产蛋期产蛋性能的影响。结果表明 :该阶段饲粮粗蛋白、蛋氨酸水平对体增重影响不显著 (P >0 0 5) ;体增重与蛋氨酸 (% )呈一定的正相关 (r=0 4574) ;CP为 1 3%、Met/CP为 0 0 2 7组采食量一直较稳定、较高 ,且饲料效率又好。代谢试验 :不同粗蛋白、蛋氨酸水平饲粮对试鸭氮存留率和能量的利用率影响显著(P <0 0 5或P<0 0 1 ) ,且它们随饲粮CP水平的升高而降低 ,随蛋氨酸水平升高而升高 ;磷的利用率也分别以CP为 1 3%的水平和Met/CP为 0 0 2 7的水平极显著地高于其他水平对磷利用率 (P <0 0 1 )。屠宰试验 :当Met/CP为 0 0 2 7时 ,体氮沉积量和体磷沉积量最佳。产蛋性能 :开产日龄和高峰日龄与 1 3~ 1 8周龄CP食入量呈弱的负相关 (r=- 0 1 83 3和r=- 0 0 984) ,与蛋氨酸食入量呈正相关 (r =0 5780和r =0 435 0 )。饲粮粗蛋白、蛋氨酸水平对 1 9~ 2 8周龄 相似文献
5.
C. Avgoulas L. Bouza A. Koutrou S. Papadopoulou S. Kosmas E. Makridou P. Papastylianou D. Bilalis 《Journal of Agronomy and Crop Science》2005,191(1):1-9
Studies were conducted in four regions of central Greece (Larisa, Karditsa, Livadia, Thiva), to evaluate the productivity and fibre properties (fibre strength and fibre length) of the five most commonly grown cotton cultivars in these regions. The experiments lasted for 6 years (1995–2000). All the characteristics tested were strongly influenced by the factors ‘year’, ‘cultivar’ and ‘region’. Significant cultivar × region, year × cultivar, region × year and cultivar × region × year interactions occurred for all the characteristics studied. The cultivar Alegria had the highest seed‐cotton and lint yield, while Aria had the lowest ones. Both cultivars gave the highest mean lint percentage but the lowest mean boll weight (MBW). Alegria had the lowest fibre strength, while Aria had the highest. The Acala‐type cultivars, Acala SJ2 and Zeta 2, had intermediate seed‐cotton and lint yield, while Vered 171 had high seed‐cotton and satisfactory lint yield. The three cultivars mentioned above had the highest MBW and very good fibre strength. Positive correlation was observed between fibre strength and length. In spite of the fact that mean fibre length was statistically the same in all cultivars, it was influenced by the factor ‘year’, as a result of different weather conditions. The year 1996 was the most unfavourable one for seed‐cotton yield and MBW, because it was characterized by lower than average air temperatures and rather dry conditions for all study sites. The factor ‘region’, a combination of different climatic conditions and cultural practices, influenced significantly all the parameters studied. 相似文献
6.
In this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha?1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha?1 was obtained with 80 kg N ha?1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha?1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings. 相似文献
7.
黄花蒿粗提物对几种害虫拒食性的初步研究 总被引:10,自引:0,他引:10
以黄花镐为原料进行浸提,经生物活性测定,结果表明黄花蒿Artenisia annua L.粗提物对供试的6种害虫均具有拒食性。其中对黑翅土白蚁Odontotermes formosanus Shiraki、赤拟谷盗Thibolium castaneum Herbst、谷蠹Rhizopertha dominica Fabricius拒食性极强,对棉蚜Aphis gossypii Glover、棉红蜘蛛Tetranychus urticae Koch及豇豆荚螟Etiella zinckenella Treitschke 也具有较强的巨食性。使用黄花蒿粗提物时,以稀释500倍和800倍效果最好,处理与对照之间有极显著差异。 相似文献
8.
为探讨解淀粉芽胞杆菌JDF-6液体发酵条件及抑菌蛋白性质,以菌量和抑菌蛋白粗提液活性为指标,采用单因素和正交试验对菌株的最适发酵培养基成分及发酵条件进行优化,同时通过硫酸铵沉淀法提取抑菌蛋白粗提液,并进行稳定性试验。结果表明,菌株JDF-6最适培养基配比为3.0%蔗糖,1%酵母粉,2%茶渣饼,0.3%硫酸锰;最适发酵条件为发酵时间120 h,发酵温度30℃,初始p H 6.5~7.0,接种量5%,250 m L装液量为100 m L。优化后菌株JDF-6抑菌活性提高51.6%,经50%饱和度硫酸铵沉淀获得的抑菌蛋白的粗提液对蛋白酶、高温(100℃以上)、紫外光(光照8 h以上)敏感,抑菌活性均下降。 相似文献
9.
本研究以新苏2号苏丹草(Sorghum sudanense ‘Xinsu No.2’)为研究对象,研究播种量与施氮量对夏播新苏2号苏丹草生产性能的影响。结果表明,当磷肥的施用量一定时,B1(播种量为22.5 kg·hm-2)和N3(施氮量为550 kg·hm-2)处理对株高的增长最有利;B1处理对主茎直径的增粗和单株分蘖数的增加最有利;B2(播种量为45 kg·hm-2)和N2(施氮量为415 kg·hm-2)处理对干草产量最有利,总干草产量分别达到19 200.0和19 744.5 kg·hm-2;B3(播种量为67.5 kg·hm-2)和N2处理的粗蛋白增产效果最佳,总粗蛋白产量分别达到1 607.03和1 572.00 kg·hm-2。从干草和粗蛋白产量来综合考虑,B3(播种量为67.5 kg·hm-2)+ N2(施氮量为415 kg·hm-2)是提高夏播苏丹草生产性能的最佳处理组合。 相似文献
10.
温度对侧耳菌降解秸秆粗纤维的影响 总被引:1,自引:0,他引:1
侧耳菌在16、20、24℃3个不同环境温度下处理玉米秸秆,通过测定秸秆中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的含量,揭示在不同温度下侧耳菌对秸秆粗纤维的降解规律。结果表明,随着处理时间的延长,秸秆NDF和ADF均呈下降趋势。处理结束时,3个温度条件下NDF降解率分别达到5.27%、8.53%和9.76%,3个处理组ADF含量分别为47.86%、46.8%和46.14%,降解率分别为3.08%、5.22%和6.56%,表明侧耳菌可以降解秸秆粗纤维,并且低温环境下降解速度较慢,降解程度较低。 相似文献