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91.
以10个球茎甘蓝品种(系)为试材,采用游离小孢子培养方法,研究胚状体发生及其再生植株获得方法。研究结果表明,添加适量6-BA不仅使胚诱导成功率达到了100%,还显著提高了出胚率;胚状体发育程度和整齐度与基因型及每皿出胚数有关;子叶期为最佳的转接时期;MS+0.5 mg/L 6-BA+0.1 mg/L NAA是最适的成苗培养基。  相似文献   
92.
Cashew is an important edible nut crop of tropics. Bulk segregant analysis (BSA) was carried out on DNA bulks constituted from F2 population and germplasm in order to link or associate molecular markers with economic characters. In all 458 RAPD, 31 ISSR and 21 pairs of SSR primers were used and identified polymorphic markers between parents. Though screening F2 bulks with these markers identified markers polymorphic between the bulks but none could be validated with the individuals of their bulks. Hence screening with germplasm bulks was carried out and could identify four RAPD markers polymorphic between the bulks for nut weight and plant stature and also between the individuals of their bulks. Of the four, three markers were associated with nut weight amplifying at 775, 475, 275, bp region in primers OPN 14, UBC 184 and UBC 185 respectively. Out of these three, two markers were specific to low nut weight and one marker was specific to high nut weight and their bands were present in greater frequency (50–77.8% and 75%) of individuals constituting the respective bulks. Similarly, the another marker UBC 185275 was detected which was specific to low plant stature and was present in 66.7% and 10% individuals constituting short and tall bulks respectively. Markers identified with bulks and with the individuals of bulks were validated further with more individuals of F2 and germplasm.  相似文献   
93.
The tomato fruit quality results of biochemical and physiological changes that occur during the ripening process. Although, the pericarp total protein profiles are less polymorphic than DNA-based markers the polymorphism in those could be directly associated with fruit quality traits. The aim of this work was to identify associations between polymorphic polypeptides from fruit pericarp at two ripening stages and fruit quality traits evaluated in two segregating populations of tomato. A cross between a normal ripening cultivar of Solanum lycopersicum (C, Caimanta) and a genotype carrying the nor (non ripening) gene (N) as well as a cross between Caimanta and a cherry type tomato of S. lycopersicum var. cerasiforme (Ce) showed genetic variance for several fruit quality traits such as fruit weight, shape, solids soluble content, acidity, color and fruit shelf life. The quantitative variations observed at phenotypic level had correspondence with the polymorphism detected in the protein profiles. Indeed, the polymophic polypeptides associated with quality fruit traits and fruit shelf life would be useful to assist tomato breeding programs as protein molecular markers.  相似文献   
94.
Germplasm of the calabash tree (Crescentia cujete L.) was collected in five major regions of Colombia, i.e. the Andes, Caribbean, Amazon, Orinoco, and Pacific regions. Collecting this multipurpose tree was guided by the indigenous knowledge of farmers and artisans in each region. Large variation in fruit shapes and sizes was found, of which some forms were typical for certain regions. Overall 56 accessions were collected and roughly classified into 22 types by eight fruit shapes and eight sizes. Molecular markers (Amplified fragment length polymorphisms) were applied to leaf tip tissue originating from vegetatively propagated plants in order to assess the diversity available in the germplasm collected as well as to detect patterns of geographical or morphological similarity. One accession each of C. alata H.B.&K. and C. amazonica Ducke were used as outgroups. Overall, genetic diversity was high (mean Nei and Li’s coefficient of 0.43). No relations could be established between either geographical provenance or fruit morphology and patterns of genetic diversity. Concerning the outgroups, the C. amazonica accession appeared to be a distinct species. The C. alata accession, however, did not seem to be sufficiently distinct from C. cujete to merit species status. The latter material may in fact be a hybrid or serve to challenge the validity of interspecific organization of the genus Crescentia.
Brigitte L. Maass (Corresponding author)Email:
  相似文献   
95.
颜艳  杜建良 《广东园林》2007,29(B09):111-114
本文通过对白云机场飞行区土壤酸化情况调查、机场土壤实地改良研究,分析现有的植物种类,并针对酸性土壤改良区适宜植物种类,基于施工难度和景观效果,提出土壤改良与植被修复措施。  相似文献   
96.
Most of Pinus brutia (Ten.) Holmboe forests are grazed, as silvopastoralism is well adapted in the Mediterranean environment. However, little attention has been paid to the demographic dynamic of the understorey vegetation even though it is strongly affected by the absorbed radiation. The purpose of this study was to examine the adaptation of herbaceous plant species under a Pinus brutia canopy, in Northern Greece. Monocultures of four plant groups (annual and perennial grasses, annual and perennial legumes) were sown in experimental areas of 50%, 70% and 100% light intensity. The density of annual and perennial grasses and perennial legumes were decreased by the shade cast by the Pinus brutia canopy. Population density of the annual legumes was little affected by light intensity: the annual grasses Bromus mollis L. and Lolium rigidum Gaudin; the perennial grasses Dactylis glomerata L. var. palestine, Festuca arundinacea and Agropyron cristatum (L.) Gaertn; the perennial legume Medicago sativa L. var. romana; the annual legumes Medicago lupulina L. and all the tested varieties of Trifolium subterraneum adapted well to the 50% light intensity habitat.  相似文献   
97.
南京主要滨河绿地植物群落的调查   总被引:8,自引:0,他引:8  
应用群落生态学方法,对南京紫霞湖、前湖、护城河与玄武湖滨河绿地植物群落的外貌、组成与结构等进行了调查。结果表明,5个绿地主要以阔叶落叶树种为主,缺少常绿树种的运用;群落结构不甚合理,乔木层相对丰富,而低矮灌木及地被层种类和数量相对缺少;人工绿地过于注重观赏品种的运用,而忽视耐水湿性种。作者认为,应结合地形和环境,合理地把握植物耐水湿性与观赏性,创造有地域特色的滨河植物景观,达到自然景观与人工景观的统一;可适当增补一些观赏性好的适生树种,提高植物景观多样性,营造城市滨河生态廊道,使其成为城市绿地系统中的组成部分。  相似文献   
98.
露天煤矿排土场植被调查与自然恢复研究(英文)   总被引:2,自引:0,他引:2  
通过分析辽宁省海州露天煤矿排土场植被组成、物种多样性及重要值的变化,研究了排土场植物群落恢复与演替的一般规律。结果表明:排土场共有植物63 种,分属于23 科,其中菊科15 种、豆科11 种、禾本科8 种;蒺藜+水稗草+猪毛菜、水稗草+大籽蒿+黄蒿、水稗草+披硷草+黄蒿+大籽蒿+黄花草木犀、芦苇+披硷草+水稗草+狗尾草分别是年限为5、10、20、40 梯田层群落的优势种群;重要值对植被重建中物种筛选有指示性,蒺藜在排土场人工恢复中可做为先锋种,披硷草、芦苇、水稗草可做为重要的优势种;排土场植被自然恢复速度缓慢,为了尽快改善生态环境,应该筛选并合理配置先锋植物和适生植物,进行植被重建,加强抚育管理,缩短演替进程。表2 参17。  相似文献   
99.
In agroforestry systems, the distribution of light transmitted under tree canopies can be a limiting factor for the development of intercrops. The light available for intercrops depends on the quantity of light intercepted by tree canopies and, consequently, on the architecture of the tree species present. The influence of tree architecture on light transmission was analysed using dynamic 3D architectural models. The architectural analysis of Acacia mangium and Tectona grandis was performed in Indonesian agroforestry systems with trees aged from 1 to 3 years. 3D virtual trees were then generated with the AmapSim simulation software and 3D virtual experiments in which tree age, planting density, planting pattern and pruning intensity varied were reconstructed in order to simulate light available for the crop. Canopy closure of trees was more rapid in A. mangium than in T. grandis agroforestry systems; after 3 years the quantity of light available for A. mangium intercrops was three times lower than under T. grandis. Simulations with A. mangium showed that practices such as pruning and widening tree spacing enable to increase the total transmitted light within the stand. On T. grandis, modification of the tree row azimuth resulted in changes in the spatial and seasonal distribution of light available for the intercrops. These results are discussed in terms of agroforestry system management.
Sylvie SabatierEmail:
  相似文献   
100.
湖南野生观赏植物及其园林应用   总被引:4,自引:0,他引:4  
湖南坐落在温带和中亚热带的植物过渡地区,拥有维管束植物5 500余种(含种下单位)。以现有欧亚和北美栽培的观赏植物为基础,湖南有2 000多种野生植物可作为栽培观赏植物,有很高的观赏价值和选育潜力。根据它们的观赏特性、抗寒性、选育潜力与园林应用的不同,可将湖南观赏植物划分为10类。将观赏植物引入园林建设,对创建地带性、个性化的园林景观具有特别重要的意义。  相似文献   
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