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131.
ZHANG Rong-Yue WANG Xiao-Yan YANG Kun SHAN Hong-Li CANG Xiao-Yan LI Jie WANG Chang-Mi YIN Jiong LUO Zhi-Ming LI Wen-Feng HUANG Ying-Kun 《作物学报》1962,47(2):376-382
The aim of this study was to assess brown rust resistance of new sugarcane varieties bred in China and main cultivated varieties in sugarcane planting area, and screen the elite new brown rust resistant varieties for popularization and application in production. In total, 60 new varieties in the national regional test of new sugarcane varieties were tested in Kaiyuan and Lincang, and 34 main cultivated varieties were studied in Lincang, Puer, and Yuxi, Yunnan province, and Yizhou, Guangxi province, China, where the incidence of brown rust was particularly high. The resistance of these sugarcane varieties to brown rust was investigated under natural inoculation and molecular marker-assisted identification was used to detect the brown rust resistance gene Bru1. The results of field survey showed that 66 (70.21%) of the 94 new and main cultivated varieties were highly resistant to moderately resistant, and 28 (29.79%) were susceptible to highly susceptible. Molecular detection indicated that Bru1 gene was found among 54 (57.45%) of the 94 new and main cultivated varieties. Some main cultivated varieties that were currently planted across large areas such as Guitang 29, Guitang 44, Dezhe 03-83, Liucheng 03-1137, Yuetang 60, and Guitang 46 were highly susceptible to brown rust, and 31 new varieties such as Yuegan 48, Funong 09-2201, Guitang 08-120, Liucheng 09-15, Zhongzhe 1, Yunzhe 08-1609, Yunrui 10-187, and Zhongtang 1201 were resistant. Therefore, in the sugarcane planting areas with high incidence of brown rust and wet and rainy climates, more effort should be eliminated the main susceptible varieties and promoted the application of new resistant varieties. This will help to achieve a reasonable distribution of varieties, fundamentally control the outbreak of disease in sugarcane planting areas, and provide security for the high-quality development of sugarcane industry in China in the future. 相似文献
132.
133.
A new locus for resistance to brown planthopper identified in the indica rice variety DV85 总被引:1,自引:0,他引:1
C. C. Su J. Wan H. Q. Zhai C. M. Wang L. H. Sun H. Yasui A. Yoshimura 《Plant Breeding》2005,124(1):93-95
The brown planthopper (BPH) is one of the most destructive insect pests of rice. Resistant varieties have proved to be one of the most economic and effective measures for BPH management. In this study, an indica rice ‘DV85’ showed resistance to biotype 2 of BPH by bulked seedling test, and a recombinant inbred line (RIL) population derived from a cross between a susceptible rice ‘Kinmaze’ and ‘DV85’ was phenotyped to map genetic factors conferring BPH resistance in ‘DV85′. Composite interval mapping revealed that one quantitative trait locus (QTL) with a LOD score of 10.1 was detected between XNpb202 and C1172 on chromosome 11. This QTL was designated as Qbph11. Qbph11 explained 68.4% of the phenotypic variance of BPH resistance in this population. The allele from the resistant parent ‘DV85’ at Qbph11 reduced the damage caused by BPH feeding and would be very useful in breeding resistant rice varieties via marker‐assisted selection. 相似文献
134.
Robert F. Park Henriette Goyeau Friedrich G. Felsenstein Pavel Bartoš Friedrich J. Zeller 《Euphytica》2001,122(1):113-127
Pathogenicity data from surveys of Puccinia triticina (formerly P. recondita f. sp. tritici) conducted in western Europe in 1995 were analysed to compare the structure of regional populations of the pathogen. Many
of the populations differed in phenotypic diversity and pathotypic composition, even though they occurred within a single
epidemiological unit, suggesting that local factors may influence the establishment and propagation of individual pathotypes
in the regional populations. Neighbouring regions were more similar than distant regions, and all regions shared at least
one pathotype, except populations in northern Italy and Scotland. A high degree of similarity was found between populations
in northern France and Great Britain, providing strong evidence of free movement of inoculum between these regions. Resistance
genes were postulated for a selection of 91 wheat cultivars, representing those most commonly grown in western Europe in 1995.
Thirteen cultivars lacked detectable seedling resistance genes and the remaining 78 possessed from one to three resistance
genes; those detected were Lr1, Lr3a, Lr10, Lr13, Lr14a, Lr17b, Lr20, Lr26 and Lr37. The most commonly detected resistance gene was Lr13, which was present singly or in combination with other resistance genes in 48 cultivars (53%). The gene Lr14a was detected in 18 cultivars, Lr26 was present in 16 cultivars. The role of host selection in the composition of the regional populations of P. triticina in western Europe in 1995 was difficult to assess on the basis of the results obtained, since virulence data were not available
for Lr13 and Lr14a.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
135.
Development and application of functional markers in maize 总被引:8,自引:0,他引:8
Thomas Lübberstedt Imad Zein Jeppe Reitan Andersen Gerhard Wenzel Birte Krützfeldt Joachim Eder Milena Ouzunova Shi Chun 《Euphytica》2005,146(1-2):101-108
Summary Functional markers (FMs) are derived from polymorphic sites within genes causally involved in phenotypic trait variation (Andersen,
J.R. & T. Lübberstedt, 2003. Trends Plant Sci 8: 554–560). FM development requires allele sequences of functionally characterized
genes from which polymorphic, functional motifs affecting plant phenotype can be identified. In maize and other species with
low levels of linkage disequilibrium, association studies have the potential to identify sequence motifs, such as a few nucleotides
or insertions/deletions, affecting trait expression. In one of the pioneering studies, nine sequence motifs in the dwarf8 gene of maize were shown to be associated with variation for flowering time (Thornsberry, J.M., M.M. Goodman, J. Doebley,
S. Kresovich, D. Nielsen & E.S. Buckler, 2001. Nat Genet 28: 286–289). Proof of sequence motif function can be obtained by
comparing isogenic genotypes differing in single sequence motifs. At current, the most appropriate approach for this purpose
in crops is targeting induced local lesions in genomes (TILLING) (McCallum, C.M., L. Comai, E.A. Greene & S. Henikoff, 2000.
Nat Biotechnol 18: 455–457). In central Europe, maize is mainly grown as forage crop, with forage quality as major trait,
which can be determined as proportion of digestible neutral detergent fiber (DNDF). Brown midrib gene knock out mutations have been shown to be beneficial for forage quality but disadvantageous for overall agronomic performance.
Two brown midrib genes (bm1 and bm3) have been shown to be involved in monolignol biosynthesis. These two and additional lignin biosynthesis genes have been
isolated based on sequence homology. Additional candidate genes putatively affecting forage quality have been identified by
expression profiling using, e.g., isogenic bm lines. Furthermore, we identified an association between a polymorphism at the COMT locus and DNDF in a collection of European
elite inbred lines. 相似文献
136.
The measurements of acid detergent fibre in rapeseed by visible and near-infrared spectroscopy 总被引:1,自引:0,他引:1
R. Font B. Wittkop A. G. Badani M. Del Río-Celestino W. Friedt W. Lühs A. De Haro-Bailón 《Plant Breeding》2005,124(4):410-412
Visible and near‐infrared spectroscopy (NIRS) calibrations for acid detergent fibre (ADF) in intact rapeseed (Brassica napus L.) were performed for two different sample volumes (10 ml, 500 seeds approximately; and 1 ml, 50 seeds approximately). The inclusion of brown and yellow‐seeded cultivars in this work has allowed the whole range of ADF currently described in the literature for this character to be covered. Chemometric techniques have been used for developing calibration equations for both procedures when measuring the two different seed sample volumes. On the basis of the coefficient of determination in the cross‐validation (R2cv) obtained for the 10 and 1 ml assays (0.80 and 0.73), and SECV/SEL ratios (2.30 and 2.57), respectively, both equations showed an accuracy sufficient for screening purposes in an ADF range from 6.80 to 13.46% dry wt, which is presented in this work. 相似文献
137.
138.
磷在棕壤中淋溶迁移特征研究 总被引:5,自引:4,他引:5
采用室内土柱淋溶模拟试验,研究相当于一年降雨条件下磷肥在棕壤土垂直方向上的淋溶迁移特征及鸡粪、秸秆对磷素迁移转化的影响。结果表明:土壤施肥量与速效磷、迟效态磷增加量呈极显著正相关。相关系数分别是0.99141。,0.99774;水溶性磷、Al—P与土壤速效磷相关性最好,相关系数分别达0.972和0.926,2500mg/kg鸡粪与25mg/kg磷肥配施能降低磷淋溶率,并能极显著提高土壤中速效磷的增加量,相当于单施50mg/kg的磷肥;秸秆与磷肥配合施用在短期内对土壤磷素的有效性影响不大,但可以减少磷素向下层迁移。 相似文献
139.
下辽河平原潮棕壤稻田的无机态氮淋溶 总被引:3,自引:0,他引:3
应用陶土渗滤管法.研究了不同施氮和渗漏条件下潮棕壤稻田的氮淋溶损失。结果表明:稻季各次施用氮肥后,60cm和90cm深处渗漏液中NH4^+-N含量都小于2mg/L。并且各施氮肥处理和对照间差别不显著;但硝酸盐淋溶比较显著,多集中在3~15mg/L之间。硝酸盐淋溶随施氮量增加而增加,90cm深度渗漏液中这一趋势更为明显。水分渗漏状况影响硝酸盐在不同土层深度的累积:渗水越快。硝酸盐淋溶深度越大。渗水较快或者施氮量高时,硝酸盐的淋溶浓度高于国际饮用水卫生标准10mg/L。施用基肥后灌水.NH4^+ -N、NO3^- -N立即出现高峰.而施用分蘖肥和穗肥后,高峰出现在施肥后10d或更久;另处基肥时期淋溶氮的浓度也比较高。 相似文献
140.
糙米是最有发展潜力的全谷食品之一,是当前受欢迎的集营养、保健于一体的功能性食品。概述了糙米研究的起源和历程,介绍了目前糙米的主要应用研究方向,指出了糙米研究中存在的问题,展望了糙米的发展前景。 相似文献