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61.
[Objective] Dimorphic InDel markers can be used for cotton variety identification and purity detection, to improve the accuracy and efficiency of cotton seed testing, and to play a role in molecular breeding of cotton. [Method] Based on the whole genome sequencing of 121 cotton varieties from different sources, the InDel markers with high polymorphism were developed according to polymorphism information content(PIC) and were applied in the genetic distance analysis and cluster analysis by using 66 cotton varieties in China. [Result] Totally 10 967 InDel were identified based on the next generation sequencing data of 121 cotton varieties. Among the 85 pairs of InDel primers synthesized, 64 were selected including 35 from At group and 29 from Dt group. The minimum average allelic frequency(MAF) of At and Dt chromosomes were 0.45 and 0.32, respectively, while the PIC were 0.49 and 0.40, respectively. The genetic distances of the 66 cotton varieties ranged from 0.04 to 0.65 centimorgan (cM), with an average of 0.39 cM. The two varieties with the largest genetic distance were Simian 3 and CCRI 36, and the two varieties with the smallest genetic distance were Xumian 18 and Xuza 3. [Conclusion] The 64 cotton dimorphic InDel markers can effectively reveal the relationships among varieties based on the genetic distance, and distinguish cotton varieties from different sources, which has certain theoretical significance and application value.  相似文献   
62.
赤峰市苦荞麦品种比较试验初报   总被引:5,自引:0,他引:5  
为筛选赤峰市适宜种植的苦荞品种,2011年在赤峰市进行9个苦荞麦品种比较试验.结果表明:西荞1号、黔苦3号、苦荞04-46、川荞1号、黔苦5号、晋荞麦2号、西荞2号、六苦2081产量均比对照CK-10-2高,适宜当地推广种植.  相似文献   
63.
构建一种基于荧光量子点免疫探针的小麦面粉中赭曲霉毒素A(OTA)的检测方法。以EDC为活化剂将CdSe/ZnS半导体荧光量子点与OTA单克隆抗体偶联,制备OTA检测探针并评价其检测性能。结果表明:制备的检测探针在3d保存期内具有良好的稳定性。当OTA质量浓度为0.1~0.9μg/L时,检测探针的荧光强度与OTA质量浓度呈线性关系,其相关系数为0.996 3,检出限为0.017 7μg/L。与国标法对照的结果说明,此方法具有可行性。小麦面粉中的加标回收试验结果显示,OTA的回收率为96.0%~102.7%,相对标准偏差不超过4.1%,说明准确性良好。可见,OTA的CdSe/ZnS荧光量子点免疫探针检测方法操作简单、准确度高、结果稳定,有望应用于小麦面粉中OTA的检测。  相似文献   
64.
Crop rotation and tillage systems have important implications for weed infestation and crop productivity. In this study, five tillage systems viz. zero tillage (ZT), conventional tillage (CT), deep tillage (DT), bed sowing (60/30 cm with four rows; BS1) and bed sowing (90/45 cm with six rows; BS2) were evaluated in five different crop rotations viz. fallow-wheat (FW), rice-wheat (RW), cotton-wheat (CW), mungbean-wheat (MW) and sorghum-wheat (SW) for their effect on weed infestation and productivity of bread wheat. Interaction between different tillage practices and cropping systems had significant effect on density and dry biomass of total, broadleaved and grass weeds, agronomic and yield-related traits, and grain yield of bread wheat. The un-disturbed soils (ZT) under fallow-wheat or mungbean-wheat rotations favoured the weed prevalence (a total weed dry biomass of 72.4–109.6 and 105.6–112.1 g m−2 in first and second year, respectively). Contrary to this, the disturbed soils (CT, DT, BS1 and BS2) had less weed infestation with either of the rotations (a total weed biomass of 0.4–7.1 and 1.1–5.4 g m−2 in first and second year, respectively). Sorghum-wheat rotation had strong suppressive effect on weed infestation in all tillage systems. The impact of crop rotation was more visible during second year of experimentation. Bed sown wheat (BS1 and BS2) in mungbean-wheat rotation had the highest wheat grain yield (6.30–6.47 t ha−1) compared to other tillage systems in different crop rotation combinations.  相似文献   
65.
籼型耐高温三系不育系巨风2A的选育   总被引:2,自引:0,他引:2  
以优质常规材料9526为母本,宜陵1B为父本杂交,优选后代与宜陵1A回交而育成的早熟中籼型三系不育系巨风2A,具有耐高温、高异交率、高配合力,所配杂交稻熟色好等优点,应用前景广泛。2014年8月通过了湖北省农作物品种审定委员会的现场鉴定,2015年通过了湖北省审定。  相似文献   
66.
田间春播法鉴定小麦新品系冬春性   总被引:1,自引:0,他引:1  
[目的]鉴定小麦新品系冬春性,为小麦品系选育提供帮助。[方法]通过田间春播法对2015年新选育的21个小麦品系进行冬春性分析。[结果]3个播期相互参考,相互印证,参加鉴定的21个品系,最终判定为1个弱冬性,13个半冬性,4个弱春性,3个春性;冬性类14个,春性类7个,冬性类品系占品系总数的66.7%。[结论]田间春播可以作为小麦冬春性鉴定的有效方法。  相似文献   
67.
Wheat–cotton rotations largely increase crop yield and improve resources use efficiency, such as the radiation use efficiency. However, little information is available on the nitrogen (N) utilization and requirement of cotton under wheat–cotton rotations. This study was to determine the N uptake and use efficiency by evaluating the cotton (Gossypium hirsutum L.) N use and the soil N balances, which will help to improve N resource management in wheat–cotton rotations. Field experiments were conducted during 2011/2012 and 2012/2013 growing seasons in the Yangtze River region in China. Two cotton cultivars (Siza 3, mid-late maturity with 130 days growth duration; CCRI 50, early maturity with 110 days growth duration) were planted under four cropping systems including monoculture cotton (MC), wheat/intercropped cotton (W/IC), wheat/transplanted cotton (W/TC) and wheat/direct-seeded cotton (W/DC). The N uptake and use efficiency of cotton were quantified under different cropping systems. The results showed that wheat–cotton rotations decreased the cotton N uptake through reducing the N accumulation rate and shortening the duration of fast N accumulation phase as compared to the monoculture cotton. Compared with MC, the N uptake of IC, TC and DC were decreased by 12.0%, 20.5% and 23.4% for Siza 3, respectively, and 7.3%, 10.7% and 17.6% for CCRI 50, respectively. Wheat–cotton rotations had a lower N harvest index as a consequence of the weaker sink capacity in the cotton plant caused by the delayed fruiting and boll formation. Wheat–cotton rotations used N inefficiently relative to the monoculture cotton, showing consistently lower level of the N agronomic use efficiency (NAE), N apparent recovery efficiency (NRE), N physiological efficiency (NPE) and N partial factor productivity (NPFP), particularly for DC. Relative to the mid–late maturity cultivar of Siza 3, the early maturity cultivar of CCRI 50 had higher N use efficiency in wheat–cotton rotations. An analysis of the crop N balance suggested that the high N excess in preceding wheat (Triticum aestivum L.) in wheat–cotton rotations led to significantly higher N surpluses than the monoculture cotton. The N management for the cotton in wheat–cotton rotations should be improved by means of reducing the base fertilizer input and increasing the bloom application.  相似文献   
68.
以油菜(Brassica campestris L.)新品种宁杂1818为试验材料,以秦优7号为对照,研究不同氮肥运筹条件下,宁杂1818的植株长势和产量变化,旨在为深入了解宁杂1818的生长特性,建立宁杂1818高产、高效栽培技术体系提供理论依据。  相似文献   
69.
利用基质栽培技术,以番茄(Lycopersicon esculentum Mill.)为供试材料,比较了天津市常用的11个番茄品种部分农艺性状、经济性状、果实营养成分指标的差异,通过对这些指标的分析,筛选出最适宜天津市基质栽培的番茄品种。结果表明,粉皇后和傲兰6号在产量、单果重等指标中表现比较突出,适合在天津市以基质栽培方式推广应用。  相似文献   
70.
根据河北省、北京市、天津市22个代表站1960—2000年逐日平均气温、降雨量、相对湿度以及日照时数等资料,运用统计学方法,分析了京、津、冀地区小麦赤霉病菌原体形成期各相关气象因子的年际、年代际变化及空间分布。结果表明,日平均气温≥12℃日数大部地区呈弱增加趋势,降雨量和雨日呈减少趋势,中部以南地区的日照条件向降低小麦抗病能力的方向转化;贴近度分析表明,塘沽一天津一保定以南地区秋季小麦赤霉病菌原体形成期的气候条件是最适宜或适宜小麦赤霉病发生。  相似文献   
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