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E. Acikgoz M. Sincik A. Karasu O. Tongel G. Wietgrefe U. Bilgili M. Oz S. Albayrak Z.M. Turan A.T. Goksoy 《Field Crops Research》2009,110(3):213-218
Despite several experiments on row spacings and seeding rates of grain soybeans, limited information is available on the most suitable row spacing and seeding rate for tall and robust forage type soybeans grown for seed. The objectives of this study were to investigate seed yield, oil and protein content, and several morphological traits as affected by row spacing (20, 40, 60 and 80 cm) and seeding rate (330,000, 660,000, 990,000 and 1,320,000 seeds ha−1) in tall and robust forage type soybeans in three irrigated Mediterranean environments in Turkey in a randomized split plot design with three replications in 2004 and 2005. Row spacings had no significant effect on plant height but tall and profusely branched plants developed in wide row spacing and light seeding conditions. Seed yield responded positively and linearly to row spacing up to 60 cm and then decreased slightly in all locations. Seed yield was the highest at 990,000 seeds ha−1 seeding rate in all three locations (3072.5 kg ha−1 in Bursa LSD = 214.7 kg ha−1, 3295.1 kg ha−1 in Mustafakemalpasa LSD = 298.6 kg ha−1 and 3311.3 kg ha−1 in Samsun LSD = 321.1 kg ha−1). Averaged across years, locations, row spacings, and seeding rates the mean seed yield was an impressive 3013.4 kg ha−1 compare with 3500.0 kg ha−1 average seed yield of grain types. Crude protein and oil content of forage type soybean were not significantly affected by row spacings and seeding rates. It was concluded that forage type soybeans can be grown for multiple purposes at the 990,000 seeds ha−1 seeding rate and 60 cm row spacings in Mediterranean environments. 相似文献
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海南树仔菜中镉含量测定及质量安全风险评估 总被引:2,自引:0,他引:2
用石墨炉原子吸收法测定采自海南几个市县栽培的树仔菜样品中镉含量.结果表明,测定的25个树仔菜样品镉含量均低于食品中污染物限量国家标准(GB 2762-2005)的0.2 mg·kg~(-1),其中有5个样品镉含量低于无公害蔬菜安全标准(GB18406.1-2001)0.05 mg·kg~(-1).依据国家有关标准,结合国内外大量的文献资料报告,按照危害识别、危害描述、暴露评估和风险描述四个步骤进行质量安全风险评估,评估结果为:海南树仔菜中镉的质量安全风险尚不足以造成对人体健康的危害. 相似文献
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高寒地区暖季草场放牧牦牛的生产性能及其土壤养分变化 总被引:3,自引:3,他引:0
旨在通过不同放牧强度下高寒小嵩草(Alpine Kobresia parva(Nees)Wang et Tang ex Y.C.Yang)草甸和垂穗披碱草(Elymus nutans Griseb.)/星星草(Puccinellia tenuiflora(Griseb.)Scribn.et Merr.)高寒混播草地暖季草场植物初级生产力、土壤养分含量以及牦牛生产性能的研究,为草地合理利用提供有益的依据。结果表明:牦牛个体增重与放牧强度均呈线性关系;高寒小嵩草草甸暖季草场最适放牧强度为1.26头/hm2,垂穗披碱草/星星草混播高寒混播草地暖季草场的最适放牧强度是7.23头/hm2;放牧强度对高寒混播草地速效氮和速效磷的影响不显著,对速效钾的影响显著(P<0.05);随着放牧强度的提高,高寒小嵩草草甸土壤有机质、有机碳、全氮、全磷的含量呈减小趋势;当放牧强度分别达到1.07头/hm2,1.08头/hm2和1.22头/hm2时,0~5 cm,5~10 cm,10~20cm土壤速效氮含量依此达到最小;随着放牧强度的提高,高寒小嵩草草甸禾草和莎草的比例下降,可食杂草和毒杂草比例增加,而高寒混播草地垂穗披碱草的比例降低,星星草和杂类草的比例增加。 相似文献
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[目的]明确海南油楠叶的化学成分。[方法]采用硅胶柱色谱对海南油楠叶的正己烷提取物和醋酸乙酯提取物进行分离,根据理化性质及波谱分析确定结构。[结果]分离得到9个化合物,鉴定为木栓酮(1)、3β-3-壬氧基-12-齐墩果烯(2)、8R,9R-环氧-β-石竹烯(3)、蒲公英萜醇(4)、豆甾烷-5烯-3-醇(5)、麦角甾-5-烯-3-醇(6)、2α,3β,-二羟基-24-去甲基-4(23)-12-齐墩果烯(7)、齐墩果酸(8)和邻苯二甲酸二戊酯(9)。[结论]化合物1~9均为首次从该植物的树叶中分离得到。 相似文献
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In vitro culture of immature embryos from Koelreuteria bipinnata var. integrifoliola 总被引:1,自引:1,他引:0
For the mass production of Koelreuteria bipinnata var. integrifoliola with selected, hybrid or genetically engineered genotypes, one potentially desirable propagation strategy is based on embryo culture. The immature embryo development in vitro from K. bipinnata var. integrifoliola was studied under different conditions of embryo age, basic culture media and plant growth regulators. The results show that: 1) germination rate of grade 3 embryos in immature seeds with 0.6–0.8 cm diameter was 98.9%. The germination rate of grade 2 embryos in immature seeds with 0.4–0.6 cm diameter was 77.8% and the germination rate of grade 1 embryos in immature seeds with 0.4 cm diameter was 15.6%. 2) The amounts of macroelements in MS medium had no clear effect on the germination rate of immature grade 3 embryos and had a modest effect on plantlet growth, where the best medium was MS or 1/2 MS. The rates were all greater than 90%. 3) The germination rate of grade 3 embryos was greater than 87% when the medium contained a low concentration of NAA or no plant growth regulators at all and decreased markedly when BAP alone or BAP and NAA together were added to the media. We suggest that in vitro culture of immature embryos from K. bipinnata var. integrifoliola can be enhanced when a small amount of plant growth regulators is added. The addition of BAP has an adverse reaction to the germination and development of immature embryos. 相似文献
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[目的]为中华青牛胆的扦插育苗提供理论依据。[方法]以野生中华青牛胆1年生健壮枝为插穗,设置3个因素(扦插基质、激素、插穗粗度)3个水平的正交试验。研究不同处理对中华青牛胆生根率、生根量以及根长度的影响。[结果]不同因素对中华青牛胆扦插生根率的影响依次为ABT 1号生根粉>基质>插穗直径。影响中华青牛胆插穗单株平均根长的主要因素是基质,以黄心土+河沙混合基质为最好;插穗直径的影响最小。影响插穗生根量的主要因素是插穗直径,插穗粗度以15.0 mm最佳,其次是基质和ABT号生根粉。[结论]中华青牛胆的扦插育苗最佳处理组合为(黄心土+河沙)+ABT 1号生根粉200 mg/L+插穗直径15.0 mm;(黄心土+河沙)+ABT1号生根粉100 mg/L+插穗直径15.0 mm。 相似文献
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