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91.
Surya P. Bhattarai Robert C. de la Pena David J. Midmore Kadirvel Palchamy 《Euphytica》2009,167(1):23-30
The importance of fast-trackt generation advancement in developing superior germplasm has been recognized in breeding of many
crop species. To address this issue in tomato, immature seeds were excised from fruit at different maturity stages and transferred
to culture medium. The best culture medium was modified full strength Moorashige–Skoog (MS) salts supplemented with 0.1 mg l−1 IAA, 0.5 mg l−1 IBA, 0.5 mg l−1 GA3 and 2% sucrose. If the excised seeds were able to grow, most showed shoot formation after a week. Seeds extracted as early
as 10 days after pollination were successfully cultured provided they were transferred aseptically and without injury. No
morphological or physiological changes in regenerated plants and their fruit relative to the parent were detected. Germination
from immature seeds of tomato is a simpler alternative to in vitro culture of immature embryos or callus, as it can be undertaken
in comparatively less stringent laboratory conditions. Using this approach, five generations can be produced in a year in
contrast to a maximum of three generations with conventional methods. This offers an opportunity for rapid generation advancement
aimed towards population development when coupled with marker assisted selection in tomato breeding for biotic and abiotic
stress tolerance. 相似文献
92.
番茄生育期的气候条件分析 总被引:1,自引:0,他引:1
探讨了番茄生长与气候条件的关系,分析了滨州市番茄种植有利的气候条件,并提出了趋利避害的生产建议。 相似文献
93.
Frederic Aparicio Salvador Soler José Aramburu Luis Galipienso Fernando Nuez Vicente Pallás Carmelo López 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(1):117-123
A polyprobe for the simultaneous detection by non-isotopic molecular hybridisation has been developed to detect any of the
following six viruses causing important economic losses in tomato crops: Tomato spotted wilt virus, Tomato mosaic virus, Pepino mosaic virus, Cucumber mosaic virus, Potato Y virus and Parietaria mottle virus. The polyprobe detected all six viruses with similar sensitivity to that obtained using individual riboprobes. In addition,
we evaluated the possible use of the tissue-printing as a sample preparation technique applied to routine diagnosis of tomato
plants with the polyprobe.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
94.
Yosuke Matsushita Tomio Usugi Shinya Tsuda 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(2):349-352
We characterised the host range and physical properties of Tomato chlorotic dwarf viroid. Among the 46 plant species inoculated with the viroid, two in the family Compositae and 23 in the family Solanaceae were
found to be systemic hosts. The viroids in the crude sap from diseased tomato plants were thermally inactivated by heating
to 100°C for at least 40 min. These viroids also lost their infectivity when diluted in phosphate buffer to at least 10−6, or after 3 days of incubation at room temperature. However, the infectivity of the viroids in dried crude sap from the plants
persisted throughout the 50-day test period. 相似文献
95.
Jun Ohnishi Toshio Kitamura Fumihiro Terami Ken-ichiro Honda 《Journal of General Plant Pathology》2009,75(2):131-139
We studied the presence of a potential transmission barrier that blocks Tomato yellow leaf curl virus in the nonvector greenhouse whitefly, Trialeurodes vaporariorum. Because T. vaporariorum can ingest and retain the virus after acquisition feeding on an infected plant, comparable to the vector whitefly Bemisia tabaci, circumstance evidence suggested that a transmission barrier presents at location(s) where the virus moves from the digestive
tract lumen to the hemolymph. To provide direct evidence for the site of a transmission barrier in the nonvector insect, we
compared the accumulation levels and localization of the virus between the two species of whiteflies. Quantitative real-time
and conventional PCR analysis showed that accumulation of the virus during acquisition feeding and retention after a short
acquisition period were indistinguishable between the two species, but the circulation of the virus within the whiteflies
differed significantly between the species. In an immunofluorescence analysis using an antibody specific to the coat protein
of the virus, the virus was restricted to the luminal surface of the midgut epithelial cells and did not enter their cytoplasm
or that of the salivary glands in T. vaporariorum. In contrast, the virus was localized within the cytoplasm of the midgut epithelial cells and in the paired salivary glands
of B. tabaci adults. This direct evidence shows that a selective transmission barrier at the luminal membrane surface of midgut epithelial
cells in the nonvector whitefly blocks entrance of the virus into the midgut epithelial cells, resulting in incompetence as
a vector of the virus. 相似文献
96.
水杨酸通过提高抗氧化酶活性及基因表达缓解番茄低钾胁迫 总被引:1,自引:0,他引:1
探讨水杨酸(SA)对低钾胁迫下番茄幼苗生理指标及基因表达的影响,为研究SA和低钾胁迫之间的关系奠定重要的理论基础。研究喷施不同浓度(0.10,0.25,0.50,1.00 mmol/L)的SA对低钾胁迫下番茄幼苗氧化酶活性及基因表达的影响。结果表明,在低钾处理下喷施0.25 mmol/L的SA,番茄幼苗中Chl、Pro的含量、CAT、APX、POD、SOD的活性与对照组相比明显增加,MDA含量则明显降低。同时采用荧光定量PCR对幼苗叶片中的APX、CAT、POD与SOD基因表达模式进行分析,发现这4个基因的表达量在处理48,96 h后明显增加。推测在低钾胁迫下喷施0.25mmol/L SA能促进APX、CAT、POD与SOD基因的表达,进而降低活性氧ROS的积累,增强番茄幼苗对低钾胁迫的抗性。 相似文献
97.
为了加强太原城郊老菜区蔬菜生产中氮素管理和降低蔬菜生产对环境的污染,在田间采用微区15N示踪法研究了番茄生产过程中农民习惯施氮(FAR)和推荐施氮(RAR)的氮肥利用效率和氮去向。结果表明:与习惯施氮比较,推荐施氮对番茄各部位干物质量、氮浓度和产量均无显著影响,且明显降低了番茄地上部吸收化学肥料氮的百分率,但对各部位氮肥利用效率和总氮肥利用效率无显著影响,氮肥利用效率仅为8%~9%,这可能与土壤原来氮库或所施有机肥矿化提供了大量氮素有关。两种施肥处理均导致65%左右的氮素损失,其中习惯施氮和推荐施氮分别导致30%和26%的氮素淋洗到40cm以下土层,为此有必要种植蔬菜后利用深根系粮食作物吸收土壤下层氮素来降低蔬菜生产对环境的影响。 相似文献
98.
99.
100.
[目的]研究秸秆生物反应堆、秸秆生物反应堆与牛粪配套措施对土壤理化性质、微生物量、酶活性及作物产量的影响。[方法]试验以常规栽培为对照(CK),研究秸秆生物反应堆(BSBR)、秸秆生物反应堆+牛粪(BSBR+CM)对土壤理化性质和微生物的影响。[结果]与CK相比,秸秆生物反应堆能显著提高土壤含水率,有效降低土壤碱性和EC值,显著增加土壤有效氮、有效磷、有效钾含量,为微生物活动提供充足的氮源,促进微生物碳氮增加以及蔗糖酶与脲酶的活性,显著增加番茄产量,配施牛粪效果更明显;BSBR+CM处理显著提升了土壤有机质含量。[结论]综合考虑认为,内置式秸秆生物反应堆配施牛粪,可以调整合理的碳氮比,对温室土壤连作以及盐渍化具有一定的修复作用,起到增产的效果,是一种较为合理的农艺措施,建议推广应用。 相似文献