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61.
Chloroplast DNA variation in 96 Prunus avium L. cultivars was assessed and compared with the results of a previous study of cpDNA diversity in 23 wild populations of the species. The polymerase chain reaction‐restriction fragment length polymorphism method was used in these studies. Approximately 9% of the chloroplast genome was analyzed, using five universal primer pairs and three restriction enzymes. Ten polymorphic fragments were common to both the wild and sweet cherry; eight polymorphic fragments were found only in the wild cherry. In the cultivars, all mutations were small (5‐30 bp) indels. In the wild populations, a point mutation was also detected in addition to indels. The mutational combinations revealed three haplotypes in the cultivars, which are the main haplotypes in the wild cherry populations. Chloroplast DNA diversity in wild cherry is higher (16 haplotypes) than in sweet cherry cultivars (three haplotypes). The probable wild origin of the sweet cherry cultivars in the maternal line, on the basis of haplotypic similarity, was discussed.  相似文献   
62.
Summary Seedlings of date palm (Phoenix dactylifera L.), obtained from seven cultivars crossed with two males, were analyzed by polyacrylamide gel electrophoresis for esterase (EST), glutamate oxaloacetate transaminase (GOT), endopeptidase (ENP) and alcohol dehydrogenase (ADH) polymorphisms. Eleven, eight, five and two phenotypes were revealed for the enzymes tested, respectively. Seedlings of F1 populations derived from Bayoud (Fusarium)-resistant and low fruit quality cultivars were characterized by a high electrophoretic polymorphism, when compared with progenies of Bayoud-susceptible and high fruit quality cultivars. In almost all cases, the most frequent electrophoretic phenotypes scored for each enzyme in different F1 populations, were similar to those of the corresponding parent cultivars. Heterozygous phenotypes have been found for, at least, 3 loci; Got-2, Est-1 and Enp, indicating that such loci could be used to screen for hybrid seedlings. The expected Mendelian segregation of allozymes has been observed for these 3 loci, in many F1 populations. It seems that progenies of Bayoud-resistant cultivars are characterized by a high level of electrophoretic polymorphism. The estimation of this index and the search for genetic linkage with segregating allozymes, may be biochemical criteria useful as an aid in distinguishing date palm seedling populations derived from Bayoud-resistant cultivars and suitable for breeding programs.  相似文献   
63.
Summary Wheat cultivars assumed to be non-susceptible to vesicular-arbuscular (VA) mycorrhizae became colonized, and this effect persisted under different growth conditions. Colonization of all cultivars was similar regardless of the amount of inoculum and the time interval of inoculation. Different plant growth temperatures and the support given by the culture media, inoculation with different endophytes, and inoculation with sterilized and unsterilized spores affected VA colonization levels, although the level of colonization reached in cv. Champlein was similar to that reached in cv. 7-Cerros under each condition. VA mycorrhizal colonization was also affected by different plant growth conditions. After VA reinoculation, the plant dry weight of Castan and 7-Cerros increased, but not Negrillo and Champlein cultivars. VA mycorrhizae increased the shoot dry weight of 7-Cerros only, but not of Champlein, when grown at 35/24°C, and had no effect on the dry weight of either cultivar grown at 18/12°C and 42/24°C. Inoculation with Glomus mosseae increased the dry weight of the cultivars more than inoculation with G. fasciculatum or G. agregatum. The effect on the plant dry weight was greater in plants grown in soil than in sand/vermiculite pots. Inoculation with sterilized and unsterilized spores of G. mosseae, either in soil pots or in sand/vermiculite tubes, did not increase the plant dry weight. Our results indicate that there was no close relationship between the level of root colonization and the effect on plant growth. The effects of accompanying microorganisms in the VA inoculum on VA mycorrhizal symbiosis are discussed.  相似文献   
64.
ABSTRACT

The content of macronutrients in potato tubers arouses interest because of their substantial consumption in the world and significant role in elements' budget in human diet. The research objective has been to evaluate the content of macronutrients in tubers of potatoes grown in different systems of crop production in Poland. In 2012–2014, an experiment was conducted to test potato cultivation in three-crop production systems: conventional, integrated and organic. In each of the six-field crop rotation systems, there were five potato cultivars classified into different earliness groups. The following macronutrients in dry mass of potato tubers were determined: N, P, K, Ca, Mg, Na, S and Cl, and the various ratios between them were calculated. The research carried out proved that potatoes production systems affect the chemical composition of tubers, which is additionally modified by whether condition and genetic features of cultivars. Potato tubers from organic farming contained by about 20% less N than tubers from conventional or integrated systems. Potato tubers from organic production system displayed lower content of Ca and Na in comparison with the conventional and integrated systems. The least of P and S were detected in tubers of the potatoes grown conventionally.  相似文献   
65.
The present study was conducted to assess the effect of soil salinity on yield attributes as well as nutrient accumulation in different plant parts of seven Brassica cultivars from two different species raised in pot culture experiment with two levels of salinity treatments along with control corresponding to soil electrical conductivity (EC) values of 1.65 (S0), 4.50 (S1) and 6.76 (S2) dS m?1. The experiment was consisted of twelve replications in a completely randomized design. Imposition of salinity stress affected various yield attributing characters including plant height, which ultimately led to severe yield reduction. However, tolerant cultivars, CS 52 and CS 54 performed better under salt treatment showing lesser yield loss. Salinity stress reduced the nitrogen (N) content in leaves of the Brassica plants, which reflected in decreased seed protein content. Reduced accumulation of iron (Fe), manganese (Mn) and zinc (Zn) was observed in leaf, stem and root at flowering and post-flowering stages, while CS 52 and CS 54 showed less reduction than susceptible cultivars under salinity stress.  相似文献   
66.
67.
土培条件下研究硼对2个硼效率不同的棉花品种花器官各部位氯、磷、钾、钙和镁含量及累积量的影响。结果表明,无论缺硼与否,2个棉花品种花器官中雄蕊、雌蕊的氯、磷、钾含量较高,苞叶和花萼中钙、镁含量较高;氯、磷、钾和镁累积量以花冠最高,花萼最低,而钙累积量则以苞叶明显较高。缺硼对不同棉花品种花器官各部位5种养分含量影响的差异不明显,但养分累积量变化却不同,缺硼胁迫下,高效品种雄蕊、雌蕊中养分累积量相对较多,苞叶相对较少,低效品种则相反,花冠和花萼中养分累积量变化的品种间差异相对较小。  相似文献   
68.
余甘子(Phyllanthus emblica L.)Vc含量分析   总被引:7,自引:0,他引:7  
采用2,6-二氯酚靛酚滴定法分析比较了余甘子各器官之间、同品种不同植株之间、不同余甘子品种之间以及与野生资源之间的Vc含量以及不同预处理方法对Vc测定的影响。结果表明.Vc在余甘子各器官中均有分布.以果实与初生幼叶中居多,茎、根中含量较低;皇帝甘与粉甘含量较多,但与其它品种的差异不大;5个野生资源单株Vc含量差异极显著。其中有3个野生单株的果肉Vc含量高于主栽品种粉甘。  相似文献   
69.
天水地区小麦品种抗条锈性变异动态监测研究   总被引:3,自引:0,他引:3  
通过系统调查和试验查明,天水地区种植的重要品种77-69和成良5号、6号已丧失抗条锈性,引致这些品种丧失抗锈性的原因主要是条中29号小种及其相近致病类型的出现和发展,山区低温为引致变异的重要诱因。提出成良5号、6号应停止种植,77-69高产可在川区控制使用,并提出了抗性比较稳定的品种。  相似文献   
70.
绿竹不同栽培类型RAPD分子标记的研究   总被引:1,自引:0,他引:1  
利用RAPD标记对22个不同栽培类型的绿竹进行多态性分析.从粗筛后的94个10 bp随机引物中筛选出20个有效引物,共扩增出113条DNA带,其中91条为多态性带,占总数的80.5%.不同引物扩增出不同的DNA指纹图谱.利用POPGEN32进行聚类分析,结果表明:聚类结果可将绿竹的不同栽培类型区分开来;这些不同栽培类型绿竹的遗传距离为0.122 2~0.815 4,大部分在0.6以下;RAPD分子标记对竹类植物种下等级进行分类有一定的意义.  相似文献   
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