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101.
102.
两种桃芽总RNA提取方法的比较研究 总被引:2,自引:0,他引:2
以‘曙光油桃’芽为试材,采用改良CTAB法、Trizol法进行总RNA提取,并通过凝胶电泳、核酸蛋白分析仪和Q-PCR检测所提取总RNA样品的质量。结果表明:改良CTAB法提取的RNA,经Q-PCR后扩增桃芽HK基因,可以得到与目的片段大小一致的条带,条带清晰,能满足基因表达分析等后续试验的要求;而Trizol法所提取的RNA,条带较弱,经Q-PCR后扩增桃树芽内HK基因,得不到与目的片段大小一致的条带,难以达到进一步试验的要求。 相似文献
103.
104.
山东肥城单植桃园食心虫发生与为害规律 总被引:1,自引:0,他引:1
为了明确食心虫在山东肥城单植桃园的生活史和对肥桃的为害,对其在该园中成虫发生动态、幼虫为害和越冬规律进行了调查研究。结果表明:桃小食心虫、桃蛀螟、梨小食心虫在山东肥城单植桃园中一年分别发生2代、3代、5代,都具有世代重叠现象,其中梨小食心虫发生数量大,对肥桃为害最为严重。幼龄桃园与老龄桃园的折梢率分别为13.70%与24.20%,但两者差异不显著;在幼龄桃园中,5、6、7月份间折梢率存在显著性差异,分别为1.80%、5.40%、33.80%,老龄桃园中,5月份的折梢率(9.20%)显著低于6、7月份的折梢率(29.40%、34.00%);肥桃树东、西、南、北、中不同方位的折梢率没有显著差异性,分别为23.00%、22.80%、25.80%、27.00%、22.00%。水蜜桃树6月份和7月份虫果率分别为10.40%和12.20%,差异不显著,其在东、西、南、北、中不同方位的分布也无显著性差异。 相似文献
105.
Peach brown rot is a severe disease caused by ascomycete fungus Monilinia fructicola and is primarily controlled by chemical fungicides. However, the utilization of fungicides has caused many problems such as microbial resistance, environmental pollution, and fruit contamination. The growing concern for food safety requires alternative management methods that are safe to humans and benign to the environment. Here we report that the extract from Coptis chinensis (a Chinese herb named “Huang Lian”) demonstrates a strong inhibition to M. fructicola. The 50% effective concentration (EC50) of C. chinensis extract to M. fructicola was only 0.91 mg/mL, while the EC50s to other fungi such as Botrytis cinerea and Alternaria solani were 14.09 mg/mL and 27.35 mg/mL, respectively. These results indicate that the extract of C. chinensis has a specific inhibition to M. fructicola. Subsequent partitioning of the ingredients in C. chinensis extract revealed that berberine, the conventional anti-bacterial alkaloid, was the predominant ingredient that exerted robust inhibition against M. fructicola. The EC50 and minimum inhibitory concentration (MIC) against M. fructicola were as low as 4.5 μg/mL and 46.9 μg/mL, respectively. Compared to berberine’s analogs in C. chinensis such as palmatine, berberine tannate and jatrorrhizine, berberine showed the strongest inhibition against M. fructicola. This finding provided insight into the structure–activity relationship between berberine and its analogs. Notably, not only can berberine prevent spore germination and hyphal growth, it also inhibits the activity of cutinase secreted by M. fructicola, implying the potential function of berberine in reducing the pathogenesis of M. fructicola. In addition, the strong in vivo inhibition of berberine against M. fructicola was observed with no visual cytotoxicity noted to peach fruits, even at berberine concentration of 400 μg/mL. Note that this was much higher than its MIC value (46.90 μg/mL). Overall berberine, as a natural compound, may be a promising candidate in control of brown rot. 相似文献
106.
[目的]为桃栽培生产提供理论依据。[方法]试验以3年生实生桃树为材料,NH4NO3为试验氮肥,设0、3、6g/盆三个施氮水平,探讨了不同施氮水平对实生桃树可溶性总糖和淀粉以及根内部组织构造的影响。[结果]根和叶片的可溶性糖含量随着施氮水平的提高呈增加趋势,以6g/盆最高,与对照及3g/盆区差异均达到0.05显著水平;淀粉含量却呈相反趋势,随着施氮水平的提高而呈下降趋势,以6g/盆含量最低,与对照达0.01显著水平。与对照、3g/盆处理相比,6g/盆根内部组织构造表现为维管中柱较大,维管束发达,皮层薄壁细胞间隙小,细胞圆润、饱满,细胞壁光滑,发育较好。[结论]适宜的施氮水平可促进桃树可溶性总糖的累积和根内部组织的发育。 相似文献
107.
108.
2009年10月份气温偏高,加上11月上中旬的强寒潮天气造成了河南省中部地区桃苗木的严重冻害。2010年1月9日对冻害发生地区的随机抽样调查表明,桃苗木未发生明显冻害的占23.9%,轻度冻害和中等冻害的占18.1%和15.3%,发生严重冻害和致死冻害的分别为24.3%和18.4%,平均冻害指数48.82。苗木高度与冻害指数呈显著正相关(r=0.893*),苗木粗度与冻害指数无显著正相关(r=0.613),不同品种冻害发生情况存在一定差异,冻害发生的边际效应非常明显。对桃苗木冻害发生的综合原因进行了分析,并就相关对策进行了探讨。 相似文献
109.
进行了20%叶枯唑可湿性粉剂防治桃树细菌性穿孔病的田间药效试验。结果表明:20%叶枯唑可湿性粉剂是防治桃树细菌性穿孔病的理想药剂,且使用安全。田间施用量为250.0mg/kg时较为经济。在发病初期开始喷药,间隔10~14d喷1次,连喷3~4次,防效达91.26%。 相似文献
110.
Rangjin Xie Xiongwei Li Mingliang Chai Lijuan Song Huijuan Jia Dajun Wu Miaojin Chen Keming Chen Maria Jose Aranzana Zhongshan Gao 《Scientia Horticulturae》2010
A total of 94 peach accessions from the Zhejiang province of China were analyzed using 34 polymorphic single-locus simple sequence repeat (SSR) markers. Genetic distance analysis divided the accessions into two major clusters, one with mainly local accessions from the Fenghua region. Preselected lines from some crosses were exclusively clustered with the local ones, possibly related to maintaining the taste quality of the fruit. The number of alleles per locus at most loci was two or three, with an average of 2.85. The value of observed heterozygosity varied from 0.05 to 0.84 (average of 0.48). Diversity within the introduced accessions was higher than that of the Fenghua local accessions. Of the accessions analyzed in this study, 94% were individually identified. Those that could not be differentiated were all derived from the ‘Yulu’ cultivar, being either mutations or of identical origin. 相似文献