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1.
【目的】目前,国内外大麦遗传转化主要利用Golden Promise品种,基因依赖性严重,尤其是大麦的转化效率较低,并且获得安全型转基因大麦植株对其进一步产业化非常重要。建立高效、无筛选标记大麦遗传转化体系,拓展大麦遗传转化的受体基因型,为大麦基因功能解析和大麦转基因育种及商业化种植提供技术保障。【方法】以优良大麦品种Vlamingh为受体,取开花授粉后14 d左右的幼胚为转化材料,通过对培养基成分及培养步骤优化,建立农杆菌介导的高效遗传转化体系,并利用该体系将BarGUS在不同T-DNA区段的双T-DNA表达载体pWMB123转化大麦,获得候选转基因植株,然后利用PCR、Bar试纸条、组织化学染色和Southern blot等检测方法,在T1代转基因植株中成功获得无筛选标记大麦转基因植株。【结果】在愈伤组织分化阶段,发现培养基中添加1.0 mg·L-1 KT、0.5 mg·L-1 6-BA和0.05 mg·L-1 NAA明显促进愈伤组织分化。在转基因植株生根阶段,发现采用添加1.0 mg·L-1的IBA的SM1(无其他生长素)的生根效果最佳,培养基中添加2.5 mg·L-1 CuSO4显著降低了大麦转基因植株白化现象。共转化了138个幼胚,最终获得14株大麦转基因植株,转化效率10.14%。PCR、Bar试纸条、GUS染色等检测证实,T0代转基因植株中均含有Bar,而仅有10株含有GUS,2个T-DNA的共转化效率为71.43%。选取4个同时含有BarGUS的转基因植株,对其自交后代进行检测,在BL8株系中筛选到2株只含GUS而不含Bar的转基因植株,无筛选标记效率为6.9%。在T1代转基因植株中对BarGUS进行了Southern blot鉴定,发现在多数转基因植株中BarGUS均为多拷贝整合,进一步证实BL8-15和BL8-19为无筛选标记的转基因植株。【结论】利用大麦品种Vlamingh为转化材料可以较高效率获得转基因植株,提高愈伤组织分化效率和转基因植株生根效率,降低转基因植株白化现象。利用农杆菌介导双T-DNA表达载体转化大麦,成功获得了无筛选标记转基因植株。  相似文献   
2.
为研究施肥对青稞干物质积累、分配及产量的调节作用,以‘藏青27’、‘QTB13’和‘QTB25’为试验材料,比较分析不同施肥处理下干物质积累、分配及产量的变化规律。结果表明:增加施肥量促进青稞分蘖期—成熟期的干物质积累及开花期和成熟期干物质向营养器官和籽粒的分配,提高了花前营养器官贮藏同化物转运量及对籽粒贡献率,降低了花后同化物输入籽粒量对籽粒贡献率。‘QTB13’和‘QTB25’在F2条件下,更有利于干物质积累及向营养器官和穗部的分配,花后同化物输入籽粒量最大,产量也最大。‘藏青27’在F3条件下,更有利于干物质积累及向营养器官和穗部的分配,花后同化物输入籽粒量和对籽粒贡献率最大,产量也最大。说明合理施肥有利于青稞干物质积累分配及产量提高。  相似文献   
3.
Transport of cadmium from soil to grain in cereal crops: A review   总被引:2,自引:0,他引:2  
Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are the primary dietary source of Cd for humans, and reducing Cd transfer from soil to their grains is therefore an important issue for food safety. During the last decade, great progress has been made in elucidating the molecular mechanisms of Cd transport, particularly in rice. Inter-and intraspecific variations in Cd accumulation have been observed in cereal crops. Transporters for Cd have been identified in rice and other cereal crops using genotypic differences in Cd accumulation and mutant approaches. These transporters belong to different transporter families and are involved in the uptake, vacuolar sequestration, root-to-shoot translocation, and distribution of Cd. Attempts have been made to reduce Cd accumulation in grains by manipulating these transporters through overexpression or knockout of the transporter genes, as well as through marker-assisted selection breeding based on genotypic differences in Cd accumulation in the grains. In this review, we describe recent progress on molecular mechanisms of Cd accumulation in cereal crops and compare different molecular strategies for minimizing Cd accumulation in grains.  相似文献   
4.
The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4–10 years of age, 410 ± 35 kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α‐amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air‐dried alfalfa and concentrate (70:30 as‐fed) in four subsequent periods of 14 days including 8 days of adaptation and 6 days of sampling. In each period and each meal, mares received concentrate either 30 min after (HC) or 30 min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic.  相似文献   
5.
Seed crops of white clover (Trifolium repens L.) are usually established with a cover crop. Provided sufficient light, white clover may compensate for low plant density by stoloniferous growth. Our objectives were (1) to compare spring barley or spring wheat used as cover crops for white clover and (2) to find the optimal seeding rate/row distance for white clover. Seven field trials were conducted in Southeast Norway from 2000 to 2003. Barley was seeded at 360 and 240 seeds m?2 and wheat at 525 and 350 seeds m?2. White clover was seeded perpendicularly to the cover crop at 400 seeds m?2/13 cm row distance or 200 seeds m?2/26 cm. Results showed that light penetration in spring and early summer was better in wheat than in barley. On average for seven trials, this resulted in 11% higher seed yield after establishment in wheat than in barley. The 33% reduction in cover crop seeding rate had no effect on white clover seed yield for any of the cover crops. Reducing the seeding rate/doubling the row distance of white clover had no effect on seed yield but resulted in slightly earlier maturation of the seed crop.  相似文献   
6.
种植密度是影响青稞抗倒伏和秸秆饲用特性的重要因子。以抗倒伏品种昆仑14号和倒伏品种门源亮蓝为试验材料,比较研究种植密度对这2个品种生长发育、抗倒伏特性和秸秆饲用特性的影响。结果表明,种植密度对2个品种的抗倒伏和秸秆饲用特性的影响存在差异。随着种植密度的增加,昆仑14号根长、根体积、根数和根干重先增后降,茎粗和壁厚依次下降;门源亮蓝根系和茎秆相关指标则随种植密度增大而下降。昆仑14号抗倒伏相关指标先增后降,但整个生育期未发生倒伏;门源亮蓝各指标均显著降低,诱发倒伏现象提前发生,致使倒伏率增大、倒伏程度加剧。昆仑14号茎秆中性洗涤纤维、酸性洗涤纤维、半纤维素、纤维素和木质素等化学成分含量随密度增加先增后降,门源亮蓝各成分含量呈下降趋势,相对饲喂价值随密度增加呈现增高的趋势。综合抗倒伏特性与秸秆饲用特性,昆仑14号最佳种植密度为375×104株hm~(-2),门源亮蓝粮饲兼用时适宜密度为300×104~375×104株hm~(-2)。  相似文献   
7.
为探讨施磷量对西藏青稞叶水势、光合、产量等因素的影响,以西藏主栽春青稞品种喜马拉雅22号为试材,通过田间微区试验,设不施磷(CK)、低磷(P2O575kg·hm~(-2))、中磷(P2O5150kg·hm~(-2))和高磷(P2O5225kg·hm~(-2))处理,测定青稞开花后4d的旗叶水势(LWP)、光合和叶绿素荧光参数,以及成熟后千粒重和产量,并利用数字图像分析法精准提取籽粒表型性状。结果表明,与CK相比,施磷可明显降低青稞旗叶水势,显著提高旗叶和倒2叶叶绿素含量,但磷肥处理间叶绿素含量差异不显著;施磷条件下青稞旗叶净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)均高于CK(除高磷处理的Tr外),其中低磷条件下最大,而高磷条件下最低;胞间CO_2浓度(Ci)随施磷量增加呈下降-平稳-下降趋势。PSII的最大量子效率(Fv/Fm)、实际光量子产量(ΦPSⅡ)、光合电子传递的相对速率(ETR)、光化学淬灭(qP)值随施磷量的增加均呈先增后降趋势,并以中磷处理最大;非光化学淬灭(qN)在CK、低磷、中磷处理间差异较小,而高磷处理时显著下降。随着施磷量的增加,籽粒二维面积、直径、周长、长度、宽度均呈增大趋势,而粒圆度呈减小趋势。随施磷量的增加,小粒和较小粒占比逐渐下降,而中粒和大粒占比逐渐提高。低磷处理下青稞千粒重和籽粒产量分别较CK提高6.66%和17.53%,中磷处理分别提高17.20%和21.10%,高磷处理分别提高8.72%和16.16%,但磷肥利用效率(PUE)随施磷量增加呈逐渐降低趋势。综合来看,在本试验条件下,青稞适宜施磷量应控制在75~150kg·hm~(-2)以内。  相似文献   
8.
Ninety-four barley genotypes were used to investigate the genotypic differences in arsenic (As) uptake and translocation and their relationships with As tolerance index (TI) and translocation factor (TF). Two As treatments (300 µM and 500 µM) were applied in the initial screening and the confirmatory experiments, respectively. The results showed significant (p < 0.05) differences in tissue biomass, shoot height, root length, As TI and TF among genotypes. Based on As TI, 11 barley genotypes were selected and divided into 3 groups, i.e. tolerant, mildly tolerant and sensitive. There was more As uptake in the roots of the As tolerant genotypes, while the As sensitive genotypes contained more As in shoots, which was further proved by the greater TF. Significantly negative correlation was observed between shoot and root As concentration. The results showed that As tolerant genotypes are able to restrict the upward movement of As, thus developing their tolerance.  相似文献   
9.
不同棱型大麦品种混种增产效果初探   总被引:1,自引:0,他引:1  
为了探索不同棱型大麦品种混种的增产机理及效果,以保山市大面积推广的多棱品种‘保大麦14号’、二棱品种‘82-1’为材料,设5个处理,进行单种和混种比较试验。结果表明,混种能充分利用空间和光能,从而提高产量,产量比单种二棱矮秆品种增加139.5~719 kg/hm~2,比单种多棱高秆品种增加40.5~720 kg/hm~2;产量构成因素中,混种的有效穗与单种二棱品种(单种中有效穗最多)相近,穗实粒数比单种二棱矮秆品种增加7.8~10.7粒,千粒重比单种多棱高秆品种增加1.2~5.5 g,同时,混种还能减轻倒伏;二棱品种‘82-1’与多棱品种‘保大麦14号’混种基本苗最佳比例为6:4(折合种子重量≈7:3)。  相似文献   
10.
大麦(Hordeum vulgare)属于禾本科植物,是我国用途最为广泛的谷物之一,广泛应用于酿造、食品、医药学等领域。大麦苗、大麦叶、大麦秸秆、大麦芽等均可作为畜禽饲料来源,具有较高的营养价值和饲用价值。将大麦开发为畜禽饲料产品,既可以缓解畜禽饲料来源不足的问题,又能够提高畜禽养殖业经济效益。介绍了大麦的营养价值,综述了其在畜禽饲料中的应用研究进展,以期为大麦在畜禽饲料领域的开发利用提供参考。  相似文献   
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