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111.
SRAP分子标记预测萝卜遗传距离与杂种优势的相关性 总被引:1,自引:0,他引:1
探讨应用SRAP分子标记分析萝卜亲本遗传距离从而预测F1杂种优势的可行性,为萝卜杂交种亲本的性状改良及F1杂种优势选配提供参考。选择来源不同、农艺性状有差异的11个耐抽薹萝卜亲本材料,按不完全双列杂交法组配30个杂交组合,运用SRAP分子标记分析萝卜亲本遗传距离以及其和萝卜农艺性状杂种优势之间的关系。结果证明:通过运用327个多态性SRAP标记来计算11个亲本间的遗传距离,其范围在0.162~0.486,且平均为0.291。亲本间SRAP标记的遗传距离与F_1杂种表现既有相关显著,也有相关不显著;与各农艺性状杂种优势相关达到极显著、显著相关或不显著相关水平,表明SRAP分子标记遗传距离在一定程度上能反映出农艺性状杂种优势的强弱,但其相关程度还不能准确地预测杂种优势。 相似文献
112.
Efficient Yield of Embryoids by Culture of Isolated Microspores of Different Brassicaceae Species 总被引:29,自引:0,他引:29
R. Lighter 《Plant Breeding》1989,103(2):119-123
Microspore culture of rapeseed (Brassica napus) is well established in practical plant breeding as a potent method to produce homozygous plants. Except for B. carinata the method has not yet been applied to other Brassicaceae species. The present study describes successful microspore culture of B. campestris, B. nigra, B. oleracea and Raphanus sativus, overcoming the break down of such microspore cultures possibly arising from the release and accumulation of toxic substances into the medium. The modified procedure is as follows: exchange of the incubation medium after one day of culture, addition of activated charcoal to the medium and aerating the three day old microspore culture by agitating the petri dishes on a specially constructed shaker. 相似文献
113.
Interspecific hybridization between the grasspea, Lathyrus sativus, and 15 wild species in Section Lathyrus is reported. Only two species, L. amphicarpos and L. cicera produced viable F1 hybrids with low fertility when crossed with L. sativus as male parent. Crosses with six other species produced pods following pollination when L. sativus was the male, but seedlings were inviable, seeds did not germinate or pods were empty or had totally shrivelled seeds. When L. sativus was the female parent, only one cross with L. gorgoni produced an F1, but the seedling was inviable. The germplasm resources of the grasspea are identified, with L. amphicarpos and L. cicera placed in the secondary gene pool and the other species in the tertiary gene pool. The definition of these germplasm resources is discussed in terms of grasspea improvement through plant breeding. 相似文献
114.
[目的]分析萝卜具有溶菌酶活性组分CBPs的分子结构,以期为其作用机制和在萝卜中的生理功能提供资料。[方法]利用亲和层析法及CM-纤维素离子交换柱层析分离纯化CBPs,测定其氨基酸组成、糖基和溶菌酶活性中心残基。[结果]从萝卜中得到了2个具溶菌酶活性且无糖基的组分:CBP1和CBP2,它们间氨基酸组成差异不大;Asp/Glu和His专一性化学修饰剂单独作用后,CBP1和CBP2相对溶菌酶活力均大幅度降低,预先加入竞争性抑制剂则下降的幅度减小。[结论]萝卜中有2个具溶菌酶活性的非糖蛋白组分,其溶菌酶活性中心氨基酸残基均可能含有Asp/Glu和His。 相似文献
115.
为了确定黄瓜根结线虫侵染早期与取食位点形成相关的WRKY基因,以根结线虫侵染早期的黄瓜根为材料,基于黄瓜全基因组WRKY基因预测,进行RT-PCR扩增.在根结线虫侵染早期的黄瓜根组织中共分离到24个WRKY基因,分别定位于黄瓜的7条染色体上.系统进化分析表明,在分离到的WRKY基因中有17个为第二家族,6个为第一家族,1个属于第三家族.初步确定8个WRKY基因为根结线虫诱导表达基因,推测黄瓜根结线虫侵染早期为涉及多个WRKY基因参与的复杂调控体系,为进一步研究黄瓜根结线虫取食位点发育机制奠定了基础. 相似文献
116.
The genetic diversity of several local populations of the fungal pathogen Cochliobolus sativus, collected over 3 years from different regions of the Czech Republic, was examined using amplified fragment length polymorphism (AFLP). A high level of variability was found even among isolates from one lesion. Measures of multilocus linkage disequilibrium suggested that recombination has a minor impact on the genetic structure of populations. Cochliobolus sativus forms genetically divergent populations (FST = 0·33), indicating a low level of geneflow between populations. This was supported by a significant correlation between genetic diversity and geographical distances up to 80–100 km. The most likely explanation for the genetic variability is that the fungus forms conidia with highly variable chromosomal rearrangements. The differentiation observed among local populations implies that genetic drift, including a founder effect, combined with restricted migration generates the structure of C. sativus populations. 相似文献
117.
黄瓜L-半乳糖-1,4-内酯脱氢酶cDNA全长的克隆和遗传转化 总被引:1,自引:0,他引:1
以黄瓜D08108果实为材料,根据GenBank中登录的甜瓜L-半乳糖-1,4-内酯脱氢酶(GalLDH)的序列设计引物,采用RT-PCR方法扩增出黄瓜GalLDH的cDNA全长,GenBank登录号为 HQ446099.黄瓜GalLDH的cDNA序列全长1880 bp,包含一个长为1773 bp的完整开放阅读框,编码590个氨基酸.其核苷酸序列与已知其他植物核苷酸序列间的同源性达70%以上.共检测得到5棵转基因植株 相似文献
118.
Francesca Cardinale Lucia Ferraris Danila Valentino Giacomo Tamietti 《Physiological and Molecular Plant Pathology》2006,69(4-6):160-171
A polynucleate Rhizoctonia isolate (R3) was analysed for virulence, growth characteristics, enzyme production and presence of dsRNAs. Taxonomic position was assessed morphologically and by anastomosis group (AG) testing and ITS sequence analysis. Results indicated that R3 is a hypovirulent R. solani AG 4. Mechanisms underlying biocontrol towards virulent R. solani and Botrytis cinerea were investigated and plant-mediated resistance was followed using biochemical markers of defence (PR1, laminarinase, chitinase). Control apparently relies on spatial and nutrient competition in soil, and on systemic induced resistance. This is the first report on induction of systemic resistance and of defence markers by a hypovirulent strain of R. solani. 相似文献
119.
黄瓜靶斑病菌接种体的繁殖 总被引:1,自引:0,他引:1
黄瓜靶斑病是近年来严重为害保护地黄瓜生产的一种新病害,为了促进靶斑病的抗病育种和防治,开展了12种固体和液体培养基配方、病菌移植方式、菌落颜色、光照条件、培养时间对黄瓜靶斑病菌繁殖效果的研究。结果表明,靶斑病菌菌落颜色深的菌株孢子产量大于菌落颜色浅的菌株;采用菌块涂抹法移植靶斑病菌效果最佳;繁殖靶斑病菌适宜的培养基为CZA120g,CZA80g,液体培养不适合靶斑病菌的繁殖;连续光照和黑暗处理对菌丝生长无显著影响,暗培养比光、暗交替和连续光照更有利于孢子的产生;28℃恒温、黑暗培养5 d是靶斑病菌产孢高峰期,分生孢子数量可达20.7×105个/mL。 相似文献
120.
WANG Shun-li Seong Sub Ku YE Xing-guo HE Cong-fen Suk Yoon Kwon Pil Son Choi 《中国农业科学(英文版)》2015,(3):469-482
Genetic transformation is an important technique for functional genomics study and genetic improvement of plants. Until now, Agrobacterium-mediated transformation methods using cotyledon as explants has been the major approach for cucumber, and its frequency has been up to 23%. For example, significantly enhancement of the transformation efficiency of this plant species was achieved from the cotyledon explants of the cultivar Poinsett 76 infected by Agrobacterium strains EHA105 with efficient positive selection system in lots of experiments. This review is to summarize some key factors influencing cucumber regeneration and genetic transformation, including target genes, selection systems and the ways of transgene introduction, and then to put forward some strategies for the increasing of cucumber transformation efficiency. In the future, it is high possible for cucumber to be potential bioreactor to produce vaccine and biomaterials for human beings. 相似文献