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21.
辣(甜)椒是我国栽培面积最大的蔬菜作物,年播种面积约2.2×106 hm2,其中甜椒约5×105hm2。生产上传统病害如疫病、病毒病等依然严峻,近年来辣椒轻斑驳病毒(PMMoV,烟草花叶病毒属)等新型流行病害爆发,严重制约甜椒生产;同时,消费者对品种的品质、多样性提出更高要求。笔者课题组先后从国内外引进甜(辣)椒种质资源1 400余份,通过鉴定、评价,筛选出具有抗病毒病、白粉病和果大、皮薄、光泽度好、品质优等优良性状的种质资源120余份。构建了与抗TMV(L3、L4)、抗番茄斑点萎蔫病毒TSWV(Tsw)等重要性状紧密连锁的分子标记,辅助育种准确率达90%以上。通过常规育种技术和分子标记相结合,创制出含有抗PMMoV(P0,1,2)L3,且兼具抗TMV、ToMV、PMMoV(P0,1,2)、CMV和疫病,果大、果实均一度高、光泽度好等综合性状优良、配合力高的甜椒骨干亲本‘0516’,以其为骨干亲本,培育出4个新一代优质、多抗、适应不同生态区的新品种‘中椒105号’‘中椒106号’‘中椒107号’‘中椒108号’。上述系列新品种含有L 3,抗TMV、PMMoV(P0,1,2),兼抗CMV和疫病;果实形状大小、色泽、整齐度等商品品质,Vc等营养品质显著提高。 相似文献
22.
马铃薯茎基腐病是影响马铃薯生产的重要病害,目前尚未有效的综合防控措施。试验的目的是通过新型腐植酸肥料与同等养分配方化肥的田间比较试验,探讨新型腐植酸有机肥对马铃薯茎基腐病预防效果。结果表明,5~15 g壤动FT/100 kg种薯配合腐植酸肥料对马铃薯生长发育安全,在出苗率、苗高、单株根数、最大根长、芽长分别优于配方化肥1.0~2.9个百分点、1.2~4.1 cm、1.1~5.2条、1.2~2.6 cm、0.3~1.1 cm;在单株薯重、平均单薯重、商品薯率、小区产量分别高于配方化肥66.7~394.4 g、4.6~12.1 g、4.3~11.4个百分点、12.23~83.46 kg/30.8m2;对主茎、匍匐茎、块茎基腐防效分别达78.29%~87.24%、75.62%~88.51%、72.05%~86.98%,增产效果达11.60%~79.12%。研究为开展农业技术防治马铃薯茎基腐病提供了新方法,对制定综合防治技术体系具有重要指导意义。 相似文献
23.
改革开放以来,福建省城镇化进程快速推进,截至2013年底福建省城镇人口达到2293万人,城镇化率提高到60.8%,高于全国平均水平。该文从福建省的城镇化规模、城镇集聚和辐射、基础设施、公用事业、人居环境、城镇体系现状分析出发,重点探讨福建省推进新型城镇化建设过程中面临的主要难题,提出以生态示范区为契机,为福建省走集约、智能、绿色、低碳的新型城镇化道路提出相应战略对策。 相似文献
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25.
《东北农业大学学报(英文版)》2016,(2):82-88
Along with the rapid advance of industrialization and urbanization process, fostering new agricultural business entities become inevitable for agricultural transformation and the construction of agricultural modernization in China. The status of the new agricultural business entities determines the level of modern agricultural development. In recent years, new agricultural business entities have grew rapidly. However, there are still many problems including the difficulties in financing loans, inadequate agricultural insurance system, bad implementation of agricultural subsidies, jagged agricultural talents and so on. In order to foster new agricultural business entities, countermeasures should be carried out to ensure financial support, perfect the agricultural insurance, strengthen the level of agricultural subsidies, strive to develop the degree of specialization agricultural operators and so on. 相似文献
26.
Kartika DEWI Hideo HASEGAWA Yuli Sulistya FITRIANA Mitsuhiko ASAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1217-1222
The present report describes Syphacia
(Syphacia) maxomyos sp. n. (Nematoda:
Oxyuridae) from two species of spiny rats, Maxomys musschenbroekii from
Sulawesi and M. whiteheadi from Sumatra. It is characterized by a
cephalic plate extending laterally with dorsoventral constriction and stumpy eggs with an
operculum rim reaching pole. It is readily distinguishable by the former feature from all
of hitherto known representatives of this genus in Indonesia, but it resembles parasites
in Murini and Hydromyni rodents in continental Asia and Sahul. This is the first
Syphacia species distributed in both the Sunda Shelf and Sulawesi with
the exception of Syphacia muris, a cosmopolitan pinworm found in rodents
of the of genus Rattus. It is surmised that S. maxomyos
is specific to Maxomys and that it was introduced to Sulawesi by
dispersal of some Maxomys from the Sunda Shelf. 相似文献
27.
Effective population size and inbreeding depression on litter size in rabbits. A case study 下载免费PDF全文
M. Ragab J.P. Sánchez M. Baselga 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(1):68-73
The purpose of this study is to use demographic and litter size data on four Spanish maternal lines of rabbits (A, V, H and LP), as a case study, in order to: (i) estimate the effective population size of the lines, as a measure of the rate of increase of inbreeding, and (ii) study whether the inbreeding effect on litter size traits depends on the pattern of its accumulation over time. The lines are being selected for litter size at weaning and are kept closed at the same selection nucleus under the same selection and management programme. The study considered 47 794 l and a pedigree of 14 622 animals. Some practices in mating and selection management allow an increase of the inbreeding coefficient lower than 0.01 per generation in these lines of around 25 males and 125 females. Their effective population size (Ne) was around 57.3, showing that the effect of selection, increasing the inbreeding, was counterbalanced by the management practices, intended to reduce the rate of inbreeding increase. The inbreeding of each individual was broken down into three components: old, intermediate and new inbreeding. The coefficients of regression of the old, intermediate and new inbreeding on total born (TB), number born alive (NBA) and number weaned (NW) per litter showed a decreasing trend from positive to negative values. Regression coefficients significantly different from zero were those for the old inbreeding on TB (6.79 ± 2.37) and NBA (5.92 ± 2.37). The contrast between the coefficients of regression between the old and new inbreeding were significant for the three litter size traits: 7.57 ± 1.72 for TB; 6.66 ± 1.73 for NBA and 5.13 ± 1.67 for NW. These results have been interpreted as the combined action of purging unfavourable genes and artificial selection favoured by the inbreeding throughout the generations of selection. 相似文献
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29.
配方施肥对毛竹林新竹生长及经济效益的影响 总被引:2,自引:0,他引:2
通过"3414"施肥试验,研究了不同N、P、K配方施肥对福建三明毛竹林新竹生长及竹林经济产出的影响。结果表明,N、P、K不同配方对新竹的成竹率、新竹胸径与新竹产量以及对竹林经济产出的影响差异显著。14个配方处理中,N2P3K2的新竹数最高,为对照的1.69倍;N2P2K2的新竹胸径和产量均为最大,分别为对照的1.09和1.91倍,且新竹叶片的N、P、K、Mg浓度最为均衡。该试验条件下,施尿素540 kg/hm2、硫酸钾135 kg/hm2、过磷酸钙450~675 kg/hm2,能较为有效地促进新竹生长与产量持续。各配方施肥对毛竹林的增产幅度为18.1%~192.4%,增产效益明显,N2P2K2的竹林产值最高,是对照的2.92倍,资金产出率(产投比)前3位为N2P2K2、N2P3K2和N2P2K3,分别是3.83,3.43和3.26,N素对新竹生长的影响最大,缺N素、P素试验的资金产出率低于无施肥处理。 相似文献
30.
报道了产自赣州市的2种江西省新记录蕨类植物:西南凤尾蕨(Pteris wallichiana J.Agardh)、岭南凤尾蕨(Pteris maclurioides Ching);广东省首次详实记录的蕨类植物:台湾毛蕨(Cyclosorus taiwanensis(C.Christensen)H.It)。标本存放于韩山师范学院生物系植物标本室(CZH)。 相似文献