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111.
小麦不同抗性品种经禾谷镰刀菌粗毒素诱导后穗内过氧化物酶(POD)、多酚氧化酶(PPOD)和苯丙氨酸解氨酶(PAL)活性均不同程度的增强,木质素含量也有所提高,感病品种升高幅度高于抗病品种。诱导抗性效果在感病品种上的表达明显好于抗病品种,诱导后激发接种三种酶活性增高幅度明显高于不诱导接种处理,表现出诱导抗病性。  相似文献   
112.
Expression profiles of ten pathogenesis-related (PR) genes during plant defense against Fusarium, Yellow dwarf virus (YDV) aphid-transmitted and Hessian fly (Hf) were compared temporally in both resistant and susceptible genotypes following pathogen infection or insect infestation. Quantitative real-time PCR (qRT-PCR) revealed that PR1, PR2, PR3, PR5, PR6, PR8, PR9, and PR15 appeared to be induced or suppressed independently in response to Fusarium, YDV aphid-transmitted or Hf during the interactions. The PR gene(s) essential to defense against one organism may play little or no role in defense against another pathogen or pest, suggesting the alternative mechanisms may be involved in different interactions of wheat- Fusarium, wheat-YDV aphid-transmitted and wheat-Hf. However, strong up- or down-regulation of PRl2 and PR14 encoding low molecular membrane acting protein, defensin and lipid transfer protein (LTP), respectively, had been detected after either pathogen infection or insect infestation, therefore showed broad responses to pathogens and insects. It was postulated that low molecular proteins such as defensins and LTPs might play a role in the early stages of pathogenesis in the signaling process that informs plants about the attack from biotic stresses. In addition, a synergistic action between different PR genes might exist in plants to defense certain pathogens and insects on the basis of comprehensive expression profiling of various pathogenesis-related genes revealed by qRT-PCR in this study.  相似文献   
113.
禾谷镰刀菌培养滤液对小麦胚根毒性作用的研究   总被引:6,自引:1,他引:6  
  相似文献   
114.
研究在离体培养条件下小麦抗、感赤霉病品种不同外植体对赤霉病菌粗毒素的反应。结果表明,随着赤霉病菌粗毒素浓度的提高。小麦幼穗及花药的出愈率降低,幼穗愈伤组织生长量减少、分化能力降低;抗赤霉病品种幼穗愈伤组织的存活率、相对生长量和分化频率降低的幅度均小于感病品种,抗病品种幼穗愈伤组织的抗坏血酸氧化酶及多酚氧化酶活性受粗毒素影响的程度小于感病材料。说明小麦成株抗赤霉病和幼穗愈伤组织抗赤霉粗毒素具有一致性。  相似文献   
115.
 用小麦黄化芽鞘生物测定法探测禾谷镰刀菌粗毒素的生物活性,以及不同抗性小麦品种对粗毒素的反应。以纯脱氧雪腐镰刀菌烯醇(DON)作比较,证明了粗毒素具有与纯毒素DON相同的生物活性。对粗毒素在抗赤霉病性鉴定应用的初步探讨中,明确了小麦品种对粗毒素的敏感性与其在田间的抗赤霉病性呈负相关。  相似文献   
116.
测定了对赤霉病抗性不同的4个小麦品种-苏麦3号、望水白(抗病)和凡6、绵阳11号(感病)穗部器官的胆碱类物质(胆碱、甜菜碱)总含量和抽提物以及胆碱对赤霉菌生长的刺激效应。结果表明,花药、颖壳和穗轴的抽提物及胆碱对赤霉菌分生孢子萌发、芽管伸长和菌丝生长有明显刺激作用。花药中的胆碱类药物质含量显著高于颖花和穗轴中的含量。花药的胆碱类物质含量在抗感品种间无显著差别;而颖壳和穗轴中的胆碱类含量,则是感病品种高于抗病品种。因此可认为胆碱是影响小麦品种抗赤霉菌在穗部扩展的一个因素。  相似文献   
117.
Fusarium graminearum species complexes (FGSCs), such as Fusarium asiaticum and F. graminearum, are important pathogens that cause Fusarium head blight (FHB) in several cereal crops worldwide. In this study, we collected 342 gramineous weed samples in the proximity of rice fields from May to June 2018 in Korea. Among the 500 Fusarium isolates from the weed samples, 13 species of Fusarium were identified, and F. asiaticum (41.2%), F. avenaceum (18.0%), F. acuminatum (16.4%) and F. graminearum (14.8%) were the most frequently isolated. The trichothecene genotype analysis showed that 206 F. asiaticum strains consisted of the nivalenol (NIV) genotype (n = 195, 94.7%) and 3-acetyldeoxynivalenol (3ADON) genotype (n = 11, 5.3%), whereas 74 F. graminearum strains consisted of the 15-acetyldeoxynivalenol (15ADON) genotype (n = 58, 78.4%) and 3ADON genotype (= 16, 21.6%). Geographical differences were observed in the FGSC and trichothecene genotype compositions, which appeared host-dependent between the southern provinces and mid-eastern provinces. The aggressiveness assessment of FHB showed that the 3ADON chemotype was most aggressive followed by the 15ADON and NIV chemotypes in wheat, while the NIV chemotype was most aggressive followed by the 3ADON and 15ADON chemotypes in rice. The F. asiaticum strains grew slowly and produced fewer conidia and perithecia than the F. graminearum strains, regardless of their chemotypes. The results of this study suggest that F. asiaticum with the NIV chemotype has a host preference for rice, and FHB-causing pathogens can be harboured in gramineous weeds, which play a role in the dispersal of FHB pathogens to rice and other cereal crops.  相似文献   
118.
 由禾谷镰刀菌引起的小麦赤霉病是小麦最主要的真菌病害之一。禾谷镰刀菌侵染小麦时分泌脱氧雪腐镰刀菌烯醇(DON)真菌毒素,威胁人畜健康。本研究通过对组蛋白乙酰转移酶基因FgHAT1的功能研究,发现该基因编码的蛋白定位于细胞核并调控组蛋白H4的乙酰化。Fghat1敲除突变体在生长发育和致病过程中表现正常,但毒素合成存在显著缺陷。敲除FgHATI导致参与DON毒素合成的TRI基因转录水平降低,突变体产毒相关的细胞分化也表现异常。外源添加cAMP可以有效回复突变体的产毒缺陷,表明FgHat1对毒素的调控与cAMP信号通路有关。研究结果表明组蛋白表观修饰和胞内信号通路之间存在联系,这两者的交叉互作对DON毒素合成的精确调控至关重要。  相似文献   
119.
Resistance to Fusarium head blight and deoxynivalenol accumulation in wheat   总被引:10,自引:0,他引:10  
Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe (telomorph =Gibberella zeae (Schw.)), is an important wheat disease world‐wide. Production of deoxynivalenol (DON) by F. graminearum in infected wheat grain is detrimental to livestock and is also a safety concern in human foods. An international collection of 116 wheat lines was evaluated for FHB resistance and concentration of DON in grain. Plants were inoculated with mixed isolates of F. graminearum in the greenhouse by injecting conidia into a single spikelet of each spike and in the field by scattering F. graminearuminfected wheat kernels on the soil surface. FHB symptoms were evaluated by visual inspection in both the greenhouse and field, and DON was analysed by HPLC. Significant differences in FHB ratings and DON levels were observed among cultivars. In the greenhouse test, visual symptoms varied from no spread of FHB from the inoculated spikelet to spread throughout the spike, and DON levels ranged from trace levels to 283 mg/kg. In the field test, DON ranged from 2.8 to 52 mg/kg. The greenhouse test identified 16 wheat lines from various origins that accumulated less than 2 mg/kg DON. These lines may be useful as sources for breeding wheat cultivars with lower DON levels. Correlation coefficients were significant between FHB symptom ratings, seed quality traits, and DON levels. Thus, the percentage of scabbed spikelets and kernels can be generally used to predict DON levels in harvested wheat grain. In breeding programmes, selection for plants having few scabbed spikelets and scabbed kernels is most likely to result in low DON levels.  相似文献   
120.
The first results of three test systems for evaluating the susceptibility of rye inbred lines to foot rot caused by Fusarium culmorum and F. graminearum are presented. The test systems were specifically designed for greenhouse, foliar tent and field experiments. The inbred lines, some of which are being used in commercial hybrids, showed significant variation for resistance. Significant interactions occurred between genotypes and test systems, and within the test systems between genotypes and years or growth stages. A significant correlation existed between susceptibility in the greenhouse and in the field (r = 0.84, P = 0.05), when inoculation in the greenhouse took place at the jointing stage (EC 31). In earlier growth stages, however, this correlation was not significant. In both greenhouse and foliar tent experiments, susceptibility to F. culmorum and F. graminearum was strongly correlated (r = 0.71, 0.87, resp., P = 0.01). In the field, F. culmorum alone was used for artificial inoculation. Genotypic variance and repeatability in the field were highest after inoculation in spring with conidia suspensions. It is concluded that, in inbreeding generations with limited seed quantities, the greenhouse and the foliar-tent test systems offer good possibilities of indirectly improving foot-rot resistance in rye.  相似文献   
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