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71.
朱丽  高淑萍    杰等 《安徽农业科学》2014,(7):1997-1999
[目的]从姜瘟病姜中分离青枯罗尔斯顿氏菌,并进行药敏试验,可为防治姜瘟病提供理论依据。[方法]采用枸橼酸盐利用试验、生化试验、底物利用试验和纸片法药敏试验。[结果]分离鉴定的10株菌的底物利用、生化试验结果符合青枯罗尔斯顿氏菌基本特性。[结论]该试验方法能鉴定青枯罗尔斯顿氏菌。  相似文献   
72.
植物病原效应蛋白功能研究方法   总被引:1,自引:0,他引:1  
植株病原会分泌一些与植物相互作用的效应蛋白,这些蛋白在病原菌与寄主植物互作过程中起着重要作用。结合几种细菌、真菌分泌的效应蛋白研究进展,介绍了用于病原菌效应蛋白研究的试验方法及其独特之处,包括图位克隆、异源表达分析等,提出研究一个单一效应蛋白需要多种分析方法。  相似文献   
73.
Abstract – In past dietary studies kokanee Oncorhynchus nerka were prominent in the diet of Pend Oreille Lake's large piscivores: native bull trout Salvelinus confluentus, cutthroat trout O. clarki and northern pikeminnow Ptychocheilus oregonensis, and introduced lake trout S. namaycush and Kamloops rainbow trout O. mykiss gairdneri. However, kokanee have declined to 10–20% of their former abundance. We therefore initiated this study to understand current predation demands on kokanee and diet overlap among piscivores, using gut content samples and analysis of stable nitrogen (δ15N) and carbon (δ13C) isotopes from the lake's fish and invertebrate community. In gut content samples, kokanee were the main prey item of large [i.e., ≥400 mm total length (TL)] bull and lake trout; a conclusion that was affirmed by stable isotope analysis. Rainbow trout >500 mm TL consumed mostly kokanee, thus there was a high degree of diet overlap among large bull, lake and rainbow trout. Small (i.e., <400 mm TL) rainbow and cutthroat trout diets overlapped, and were composed mostly of littoral benthic invertebrates. However, gut content and stable isotope analysis did not accord for 400–500 mm TL rainbow trout, small lake trout, and large cutthroat trout. In these instances, a linear mixing model using stable isotope results predicted kokanee consumption for each species, but no kokanee were identified in rainbow or lake trout gut content. Gut content and stable isotope analysis of native northern pikeminnow indicated a diet of mostly littoral benthic invertebrates at smaller (100–150 mm TL) lengths, with kokanee becoming more prominent in the diet of individuals >300 mm TL. Percent of kokanee in the diet of northern pikeminnow has declined from a prior study; otherwise piscivore diets have apparently remained unchanged. In this study, judgments as to the feeding of some piscvores, based on gut content alone, would be tenuous because of small sample sizes, but stable isotope analysis provided an efficient means for confirming diets.  相似文献   
74.
Biofumigation, as originally defined, is the use, in agriculture, of the toxicity of Brassica crop residues to control soilborne plant pathogens. This toxicity is specifically attributed to the release of toxic isothiocyanates, through the hydrolysis of glucosinolates present in the crop residues. This technique is considered a possible alternative to the use of pesticides, but field studies have generated conflicting data concerning the efficacy of biofumigation at field scale, limiting the use of this technique. Analytical studies based on a systematic approach involving evaluation of the potential effects of isothiocyanates can be used to address this problem in a rigorous manner. However, many recent studies have indicated that the mechanisms underlying biofumigation are much more complex than a simple toxic effect of residues. In this review, we dissect and discuss the problems encountered when trying to understand the variability in biofumigation efficacy and propose an integrative epidemiological approach to overcome these problems. This approach involves separating the effects of the different parameters of the system, such as the effects of different management phases of the biofumigant crop (i.e. the period of biofumigant crop growth and the phase during which crop residues are pulverised and incorporated into the soil) on the epidemiological mechanisms driving the development of an epidemic (density of primary inoculum and dynamics of disease progression). Finally, we propose new avenues of research into biofumigation in which the use of epidemiological tools and methods may improve our understanding of the factors underlying variation in the efficacy of biofumigant crops.  相似文献   
75.
经过数年调查发现,安徽省境内的杉木上斑痣盘菌科病原菌共4属5种,它们是杉生小双梭孢盘菌Bifusella cunnighamiicola Korf & Ogimi,皮特拉克散斑壳Lophodermium petrakii Durrian,毁坏舟皮盘菌Ploioderma destruens Y.R.Lin et Hou,汉德尔舟皮盘菌P.handelii (Petrak) Y.R.Lin et Hou和杉木小鞋孢盘菌Soleella cunnighamiae Shao et Zinno.文中描述了各种菌的主要特征,并编制了种的检索表以资识别.对于长期以来杉木落针病病原鉴定中所存在的同物异名问题也进行了商榷.  相似文献   
76.
鸭传染性浆膜炎的病原分离鉴定与药防研究   总被引:4,自引:0,他引:4  
本研究从四川、重庆等地鸭传染性浆膜炎鸭群中分离出可疑致病菌株19株,经生化鉴定为鸭疫里默氏菌,血清型鉴定除1株属Ⅱ型外,其余均为Ⅰ型;通过协同药物敏感性测定,研制出新型复方制剂“鸭浆灵”,经控制试验与临床应用效果显著。  相似文献   
77.
The Exploitation of Crop Allelopathy in Sustainable Agricultural Production   总被引:10,自引:0,他引:10  
Crop allelopathy may be useful to minimize serious problems in the present agricultural production such as environmental pollution, unsafe products, human health concerns, depletion of crop diversity, soil sickness and reduction of crop productivity. Several crops including alfalfa, buckwheat, maize, rice, rye, sorghum, sunflower, wheat, etc. are affected either by their own toxicity or phytotoxin exudates when their residues decompose in the soil, that show strong suppression on weed emergences. Allelopathic crops when used as cover crop, mulch, smother crops, green manures, or grown in rotational sequences are helpful in reducing noxious weeds and plant pathogen, improve soil quality and crop yield. Those crop plants, particularly the legumes, incorporated at 1–2 tons ha−1 (alfalfa, buckwheat, rice by-products), which can give weed reduction and increase of rice yield by 70 and 20 %, respectively, are suggested for use as natural herbicides. Allelochemicals from allelopathic crops may aid in the development of biological herbicides and pesticides. Cultivating a system with allelopathic crops plays an important role in the establishment of sustainable agriculture. The introduction of allelopathic traits from accessions with strong allelopathic potential to the target crops will enhance the efficacy of crop allelopathy in future agricultural production.  相似文献   
78.
K. Alix    C. Lariagon    R. Delourme    M. J. Manzanares-Dauleux   《Plant Breeding》2007,126(2):218-221
Clubroot, caused by the obligate biotroph Plasmodiophora brassicae Woron., is one of the most damaging diseases of Brassica crops in the world. Because the pathogen can infect all the Brassicaceae, including Arabidopsis thaliana, possible advantages have been found by identifying sources of resistance to P. brassicae in this model plant. Fifty‐seven ecotypes of A. thaliana, including the INRA Arabidopsis core collection, were assessed for resistance to clubroot disease. Ecotypes Burren (Bur‐0), Tsu (Tsu‐0) and Kaunas (Kn − 0) were identified as partially resistant to P. brassicae isolates eH and/or Ms6. Fifteen Arabidopsis mutant lines known for certain physiological processes potentially involved in the host‐pathogen interaction were evaluated for their resistance/susceptibility to P. brassicae. Mutant axr3‐1 appeared to be less susceptible than the wild type Columbia, supporting the hypothesis of the involvement of the auxin pathway in the development of clubs.  相似文献   
79.
荸荠秆枯菌(CylindrosporiumeleocharidisLentz)生长发育温度8~35℃,最适于菌丝体生长、产孢的温度为25~30℃,20~28℃孢子萌芽率较高。致死温度46℃10min。病菌在RH75%以上生长良好,其产孢量则随湿度升高而增加。RH81%以上孢子可以发芽,饱和湿度再加水滴时发芽率最高。PH4.50~9.13均较适于病菌生长,产孢量则以在PH6.94~9.13时较多,PH4.20~7.60较适宜孢子发芽。连续黑光灯照射有促进孢子形成和菌丝体旺盛生长的作用。此菌对多种单糖、双糖和多糖都能利用,以蜜二糖、麦芽糖、葡萄糖等产孢量较多。适于病菌生长和产孢的氮源是甘氨酸、DL-α-氨基丙酸和氨基乙酸,脲素较差。  相似文献   
80.
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