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91.
以野蔷薇(Rosa multiflora)的冬末初春芽和夏初叶片为材料,研究了DNA的提取方法,并对影响随机扩增多态DNA(RAPD)的反应因素进行了优化.建立了适合野蔷薇RAPD的反应体系和反应程序,在20μL反应体系中,25ng模板DNA,2.0mmol/LMgCl2,0.2mmol/LdNTPs,1UTaqDNA聚合酶,0.1μmol/L引物.扩增程序为:94℃预变性4min,然后94℃变性45s,37℃退火1min,72℃延伸1min,37个循环,最后72℃延伸5min,4℃保存. 相似文献
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94.
A. Omrani-Sabbaghi M. Shahriari M. Falahati-Anbaran S.A. Mohammadi A. Nankali M. Mardi B. Ghareyazie 《Scientia Horticulturae》2007
To study the genetic variation in Iranian olive collections and some foreign olive cultivars, 47 accessions of 18 local cultivars from 6 olive collections of Iran (Roudbar, Zanjan, Ahvaz, Dezful, Kazeroon and Shiraz), were analyzed along with 30 imported cultivars using 16 microsatellite primer pairs. All the used microsatellite loci revealed polymorphism in the studied genotypes, except GAPU14 and GAPU113 markers. Fourteen microsatellite primers amplified 126 polymorphic alleles in the 87 selected olive accessions. The average number of alleles per locus was 9, ranging from 3 to 14. Polymorphic information content (PIC) was 0.85. The genetic similarity based on Jaccard coefficient ranged from 0.15 to 1. The genetic relationships among accessions were investigated using cluster analysis and principal component analysis (PCA). Most of the accessions with the same name were grouped together; some exceptions were also observed. As expected, close relationship was observed among accessions within same cultivar. Most of the Iranian olive accessions were clustered to a main distinct group. Two-dimensional scatter plot of principal component analysis revealed a clear separation of most of the Iranian olives from Syrian and other introduced cultivars. These suggest that Iranian cultivars have different origin related to West Mediterranean basin cultivars and have evolved independently from the others. Between and within Iranian and foreign cultivars (cultivars including three or more accessions) genetic diversity was analyzed using analysis of molecular variance (AMOVA). AMOVA revealed higher within cultivar genetic variation (62.76%) as compare to that between cultivar variations (37.24%). The intra- and inter-cultivar variance tested by permutation test showed significant genetic variation at both levels. The high level within cultivar genetic variance could be due to mislabeling and presence of homonyms in cultivars produced by vegetative propagation from original plants. 相似文献
95.
Néjia Zoghlami Ichraf ChritaBadra Bouamama Mahmoud GargouriHassène Zemni Abdelwahed GhorbelAhmed Mliki 《Scientia Horticulturae》2007
In this work, we report for the first time on the analysis of genetic diversity within a set of 36 Tunisian Opuntia ficus indica (L.) Mill. ecotypes using RAPD markers. 相似文献
96.
用RAPD标记分析高羊茅的遗传多样性 总被引:6,自引:5,他引:6
采用RAPD分子标记技术对从国外引进的15个高羊茅品种的遗传多样性进行了研究。从60个随机引物中筛选出12个有效引物,它们共扩增出85条DNA带,其中59条为多态性带,占69.41%,平均每个引物扩增出多态性带4.92条;利用NTSYS-PC软件计算出的不同品种间Jaccard遗传相似系数(GS)变化范围较大,为0.373~0.932;根据得到的遗传相似性矩阵进行非加权组法(UPGMA)聚类分析,建立高羊茅品种的分子系统树状图;以相似系数0.68为标准,可将所有品种分为3类,品种翠丽和贝克各自聚为一类,其余13个品种聚成一类。 相似文献
97.
B. Shiran N. Amirbakhtiar S. Kiani Sh. Mohammadi B.E. Sayed-Tabatabaei H. Moradi 《Scientia Horticulturae》2007
RAPDs and SSRs were used to study the genetic diversity of Iranian almond cultivars and their relationship to important foreign cultivars and three related species. Eight unidentified almond Shahrodi cultivars and three wild almonds (Prunus communis, Prunus orientalis and Prunus scoparia) were also included. Of the primers tested, 42 (out of 80) RAPD and 18 (out of 26) SSR primers were selected for their reproducibility and high polymorphism. A total of 664 polymorphic RAPD bands were detected out of 729 bands. The number of presumed alleles revealed by the SSR analysis ranged from 3 to 10 alleles per locus with a mean value of 6.64 alleles per locus. Both techniques discriminated the genotypes very effectively, but only RAPDs were able to discriminate the cultivars Monagha and Sefied. Results demonstrated an extensive genetic variability within the tested cultivars as well as the value of SSR markers developed in peach for characterization of almond and related species of Prunus. Dice similarity coefficient was calculated for all pair wise comparisons and was used to construct a UPGMA dendrogram. For both markers a high similarity in dendrogram topologies was obtained although some differences were observed. All dendrograms, including that obtained by the combined use of both the marker data, depicted the phenetic relationships among the cultivars and species, depending upon their geographic region and/or pedigree information. Almond cultivars clustered with accession of P. communis showing their close relationship. P. orientalis and P. scoparia were clustered out of the rest of P. dulcis. 相似文献
98.
B. Román C. I. González Verdejo Z. Satovic M. D. Madrid J. I. Cubero S. Nadal 《Phytoparasitica》2007,35(2):129-135
Some species of the genusOrobanche are among the most devastating parasitic weeds, causing extensive damage in agricultural fields. Considering the difficult
control due to seed longevity in the soil, small seed size, high fecundity and a subterranean phase that allows them to parasitize
the host before they emerge and become evident, the development of diagnostic markers is highly recommended. In our study
we identified potential molecular diagnostic markers from the plastid genome in order to distinguish among the most importantOrobanche species attacking crops in Andalusia, the southern region of the Iberian Peninsula. The study has consideredO. crenata, O ramosa andO. cumana causing serious losses in legumes, solanaceous crops and sunflower fields, respectively, andO. minor that, although abundant in Andalusia, has to our knowledge not yet been found parasitizing agricultural hosts. We amplified
a non-coding region from the plastid genome, studied sequence differences among the amplified fragments and digested those
of the same length with selected restriction enzymes. Here, we propose a molecular protocol to distinguish the main parasitic
plants in crop fields of southern Spain. Different applications such as identification ofOrobanche seeds in soil or crop seed lots are discussed in order to offer right crop recommendations or to prevent new infestation
of parasite-free fields. Recommendations for further development of these diagnostic markers are also considered.
http://www.phytoparasitica.org posting Jan. 15, 2007. 相似文献
99.
Trabelsi Darine M.B. Allagui M. Rouaissi A. Boudabbous 《Physiological and Molecular Plant Pathology》2007,70(4-6):142-148
Nine isolates of Phtophthora nicotianae were isolated from infected pepper plants. Their pathogenicity was studied in Capsicum annuum in comparison with P. nicotianae isolates from tomato and tobacco. The pathogenicity test showed that pepper isolates of P. nicotianae are adapted to their host. Banding patterns obtained by RAPD analysis with six oligonucleotide primers revealed polymorphism that grouped the isolates independently of the plant host. The polygenic dendrogram showed that pepper isolates were more similar to tomato isolates than to tobacco isolates. The RAPD bands of 1300 and 1500 bp, detected with primers OPD-01 and OPD-10, respectively, appeared specific to the most pathogenic pepper isolates. The OPK-08-1950 seems specific to the isolates of P. nicotianae from tomato. These results suggest that host specified might occur in P. nicotianae and that may be due to interspecific hybridization events resulting in novel pathogenic behavior. 相似文献
100.
Toshiyuki Usami Shu Ishigaki Hiroko Takashina Yuko Matsubara Yoshimiki Amemiya 《Journal of General Plant Pathology》2007,73(2):89-95
Japanese isolates of Verticillium dahliae, a causal agent of wilt disease in many plants, are classifiable into pathotypes based on their pathogenicity. Because these
pathotypes are morphologically indistinguishable, establishing a rapid identification method is very important for the control
of this pathogen in Japan. For cloning DNA fragments that are useful for identification and specific detection of V. dahliae pathotypes, we performed random amplified polymorphic DNA (RAPD) analyses using various isolates. One polymerase chain reaction
(PCR) product, E10-U48, was specific to isolates pathogenic to sweet pepper. The other product, B68-TV, was specific to race
1 of isolates pathogenic to tomato. The specificity of these sequences was confirmed by genomic Southern hybridization. Further
analyses revealed that the region peripheral to B68-TV obtained from the genomic DNA library includes the sequence specific
to all isolates pathogenic to tomato (races 1 and 2). Moreover, sequence tagged site (STS) primers designed from B68-TV and
its peripheral region showed race-specific and pathotype-specific amplification in a PCR assay. The probes and primers obtained
in this study are likely to be useful tools for the identification and specific detection of pathotypes and races of V. dahliae.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB095266. 相似文献