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21.
An outbreak ofDichelia cedricola (Diakonoff) (Lep.: Tortricidae), the cedar shoot moth (CSM), began in spring 1998 and lasted 3 years. This was the first
monitored outbreak of the CSM in Isparta, Turkey. Tree crowns recovered to near normal condition by the middle of each growing
season (in early June) during the outbreak. Tree volume and volume element increments were examined throughout the outbreak
cycle from 1954 to 2001. In the past, CSM activity in stands of Lebanon cedar (Cedrus libani A. Rich.) was assessed through radial increment analyses. Cedar tree ring chronologies were analyzed for evidence of the
CSM. Tree-ring chronologies from nonhost cedar (nondefoliated sample trees) were used to estimate potential growth in the
host cedar (defoliated sample trees) during current and past outbreaks; all trees selected were the same subspecies and varieties.
Regional outbreaks of the CSM were identified by synchronous and sustained growth periods of the trees. In 2001, increment
cores were collected from 17 host and 16 nonhost dominant or codominant trees and annual radial growth indices from 1954–2001
were calculated for each of two host and two nonhost sample plots. Growth functions were defined as the cumulative sum of
radial, height, and volume increment, and were graphically compared between CSM host cedar and nonhost cedar trees. Tree ring
evidence suggests that a large-scale outbreak occurred in 1955 (from 1955 to 1966) and a small outbreak occurred in 1985 (1985–1990)
and in 1998 (1998-continued) in the study area. The average diameter growth reductions around 1955, 1985 and 1998 were 40%,
46% and 7% of potential, respectively. It was concluded that a narrow latewood band is significant indicator of defoliation
by the CSM and the outbreaks appear to be associated with dry winter and spring weather prior to the autumn and winter in
which wood feeding occurred.
http://www.phytoparasitica.org posting Nov. 24, 2004. 相似文献
22.
中国果树类病毒的发生及其研究进展(英文) 总被引:4,自引:0,他引:4
概述了在中国发生且己鉴定明确的5种果树类病毒,即苹果绣果类病毒(Apple scar skin viroid,ASSVd)、梨泡状溃疡类病毒(Pear blister canker viroid,PBCVd)、葡萄黄斑类病毒-1(Grapevine yellow speckle viroid-1,GYSVd-1)、柑橘裂皮类病毒(Citrus exocortis viroid,CEVd)和桃潜隐花叶类病毒(Peachlatent mosaic viroid,PLMVd)的研究进展,包括病害的首次发现、症状特征、发病规律、检测方法与防治对策以及这些类病毒的生物学与分子生物学特性。 相似文献
23.
蛋白质组学研究技术及其在果树学中的应用 总被引:7,自引:3,他引:7
蛋白质组研究是当今生命科学发展的一个新的增长点,它能阐明基因组所表达的真正执行生命活动的全 部蛋白质的表达规律和生物功能。简要介绍了蛋白质组学产生的科学背景、研究方法和研究内容。蛋白质组学研究 方法主要有双向聚丙烯酰胺凝胶电泳(2D-PAGE)、质谱(Mass-spectrometric)技术、蛋白质芯片(Protein chips)技术、酵母 双杂交系统(Yeast two-hybrid system)、双向高效柱层析和生物信息学等。其应用的范围包括植物群体遗传学、在个体 水平上植物对生物和非生物环境的适应机制、植物的发育和组织器官的分化过程,以及不同亚细胞结构在生理生态 过程中的作用等诸多方面。同时展望了植物蛋白质组学研究前景以及蛋白质组学技术在果树学中的应用前景。 相似文献
24.
Hitomi NAKABAYASHI Yasuyuki YAMAJI Satoshi KAGIWADA Masashi UGAKI Shigetou NAMBA 《Journal of General Plant Pathology》2002,68(2):173-176
The complete nucleotide sequence was determined for genomic RNA of White clover mosaic virus (WClMV-RC) isolated from red clover (Trifolium pratense) in Japan, It is 5843 nucleotides in length, excluding the poly(A) tail at the 3' terminus. Similar to other potexviruses,
it contains five open reading frames (ORFs 1 through 5), which putatively encode an RNA-dependent RNA polymerase (RdRp) (147
kDa), a triple gene block (TGB) (26 kDa/13 kDa/7 kDa), and a coat protein (CP) (22 kDa), respectively. The deduced amino acid
sequence of the WClMV-RC CP was identical to that of WClMV-O, one of two New Zealand isolates, but only 85% identical to that
of WClMV-M, the other New Zealand isolate, because of heterogeneity in the C-termini of CP amino acid sequences. The implication
of this CP heterogeneity is discussed.
Received 30 August 2001/ Accepted in revised form 11 January 2002 相似文献
25.
J.C. Goud A.J. Termorshuizen 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(8):771-782
Two experiments were performed in two consecutive years to test whether isolates of different vegetative compatibility groups (VCGs) differ in their ability to cause disease in woody ornamentals, to study the host specificity of the isolates and to get an insight into disease development in woody hosts. A range of woody ornamental plant species, including Acer campestre, Acer platanoides, Acer pseudoplatanus, Catalpa bignonioides, Cotinus coggygria, Robinia pseudoacacia, Rosa canina, Syringa vulgaris and Tilia cordata, were root-dip inoculated with six isolates of Verticillium dahliae, belonging to the two VCGs that occur in the Netherlands (VCG NL-1 and VCG NL-2). Isolates belonging to each VCG caused severe symptoms of verticillium wilt in most plant species tested. Disease progress differed between plant species, but was generally the same for the two VCGs. No overall differences in virulence were observed between the two VCGs for external wilt symptoms, number of dead plants, or shoot length. No significant VCG × plant species interactions were present for these characteristics. However, isolates of VCG NL-1 caused more vascular discolouration than did isolates of VCG NL-2. Isolates within VCGs often differed considerably in their virulence to certain hosts, as shown by highly significant isolate × plant species interactions. Isolates were more virulent on their original host. These findings imply that VCG identification does not contribute to disease prediction for a range of woody hosts. 相似文献
26.
Thomas Thomidis 《Phytoparasitica》2002,30(2):191-193
The virulence ofPhytophthora citrophthora isolated from various host-plants on three peach rootstocks (GF677, PR204, KID I) was examined. There was no significant
difference among the rootstocks with respect to their susceptibility to testedP. citrophthora isolates. The most virulent isolate originated from sycamore (Acer pseudoplatanus); isolates from pistachio trees (Pistacia vera) also showed high virulence but were significantly less virulent than the sycamore isolate. Isolates originating from plum
(Prunus domestica), almond (Prunus amygdalus) and lemon (Citrus limon) trees were moderately virulent on peach rootstocks; those from cyclamen (Cyclamen persicum) showed the lowest virulence of those tested. There was thus great variation in virulence among the testedP. citrophthora isolates. It is possible that the isolates ofP. citrophthora from sycamore, pistachio, plum, almond and lemon trees are a threat to peach trees, whereas the low virulence of the isolates
from cyclamen hosts suggests that these pathogens are not a serious threat to peach trees.
http://www.phytoparasitica.org posting Jan. 3, 2002. 相似文献
27.
许多固氮树种速生丰产,萌生能力强,叶片,木屑含氮率较高,可为食用菌栽培提供理想原料,而且固氮树种在绿花荒山,保持水土,提高地力方面作用显著,以固氮树种发展短轮伐期食用菌专用林,具有较高的经济效益和生态效益,本文介绍了银合欢,黑荆,大叶相思,银荆,桤木,南洋楹和马占相思等在食用菌栽培上的应用概况,各地可因地制宜栽培合适的固氮树种作为食用菌专用林。 相似文献
28.
几种落叶果树H2O2含量变化与自然休眠关系的研究 总被引:18,自引:2,他引:18
以设施栽培中常见的几种核果类果树品种和两个葡萄品种为试材, 分析了芽休眠期间 H2O2含量变化动态, 并探讨了温度、生长调节剂及化学破眠物质对H2O2含量影响的效应。结果表明: 休眠期间,不同树种( 品种) 芽内 H2O2含量存在差异, 基本趋势是晚熟品种高于早熟品种, 花芽高于叶芽, 但葡萄品种相反, 早熟的‘京秀’高于晚熟的‘巨峰’; 休眠期芽内 H2O2含量基本呈稳步上升后急剧下降的趋势,不同品种急剧下降的时间略有差别, 且与自然休眠解除的时间相吻合。低温(5 ℃) 处理显著增加了芽中 H2O2含量, 中温(10 ℃) 使 H2O2含量略有增加, 而高温(20 ℃) 却导致 H2O2含量降低。休眠前期50 mg.L-1 ABA 处理显著提高了芽中H2O2含量, 而100 mg.L-1的GA3和6-BA 处理有减少 H2O2含量的趋势, 但二者差异不明显。热带地区常用的化学破眠物质对芽 H2O2的影响因树种( 品种) 、使用时期不同而异, 硫脲、KNO3前期使用对核果类果树影响明显, CaCN2对核果类无明显效应, 但对葡萄品种作用显著。果树芽 H2O2含量的动态变化表明, H2O2可能是低温解除自然休眠的原因。 相似文献
29.
30.
苹果粗皮病与锰含量的关系 总被引:14,自引:2,他引:14
对胶东半岛部分发生苹果粗皮病(IBN)的果园的土壤和植株进行了分析测定,结果表明:发生苹果粗皮病的果园土壤有效锰含量较高,而且粗皮病严重果园高于粗皮病较轻果园。发生粗皮病的苹果树花器官中锰含量较高,粗皮病最严重的姜格庄果园苹果树花器官中锰平均含量比观水镇高出139.28mg/kg,比季家埠重病园和轻病园分别高122.34和182.19mg/kg。从4月到10月,苹果粗皮病逐渐加重,叶片中锰含量逐步增高。10月份姜格庄果园最高锰含量达1717.85mg/kg,平均锰含量达1119.69mg/kg,而粗皮病较轻的季家埠果园则仅306.03mg/kg,前者比后者高265.88%。对不同部位锰含量测定表明,锰含量在叶片中最高,其次是韧皮部,木质部最低。表明胶东半岛苹果粗皮病的发生是因为锰过量。可能是土壤锰含量高,pH值低,降雨多,施肥不合理等,造成土壤锰有效性增加.导致树体吸收过量而出现粗皮病害。 相似文献