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61.
The study of the soil properties and geochemistry of vineyard soils of the Méntrida Protected Designation of Origin (PDO) (central Spain) was performed to better understand the role of soil as a terroir component and to contribute to sustainable vineyard management. Soil physico-chemical characteristics were determined, along with the content of trace elements (by placing emphasis on rare earths) in topsoils and subsoils. The dominant soil types were Inceptisols, Alfisols and Entisols (USDA soil classificacion), i.e., Cambisols, Luvisols and Regosols in the World Reference Base for Soil Resources (WRB) system. They were all deep and well-structured. Our findings reveal that soil-available nitrogen (N) ranged from 0.03 to 0.21 (%), with soil-available phosphorus (P) ranging from 0.20 to 40.50 (mg·kg−1). pH had a mean of 6.33 (range: 4.4–8.7) in the ten observations, and a degree of mesotrophic saturation in bases (V%), except in one that had a 100% value (soils where carbonates were absent, save exceptional cases). A medium to high cation exchange capacity (CEC) was found (range: 9.8–38.3 cmol·kg−1). The mean values of elements' contents were (mg·kg−1): Sc 14.8, V 32.13, Cr 23.09, As 4.01, Ni 8.57, Cu 6.43, Zn 30.13, Rb 143.49, Sr 63.03, Y 15.39, Ba 374,44, La 25.87, Ce 43.77, Pb 22.25, Nd 21.28. They decreased in this order: Ba > Rb > Sr > Ce > V > Zn > La > Cr > Pb > Nd > Y > Sc > Cu > As. The results confirm the importance of soils for the PDO, with an optimum condition to produce grapevine quality laying the foundations to obtain a good wine. Our findings provide insights into the importance of pedological properties for regulating soil nutrient availability across soil types, and support soil resource utilization management in regional viticulture.  相似文献   
62.
晚红葡萄在反复干旱胁迫下的水分生理反应   总被引:7,自引:0,他引:7  
采用盆栽2年生自根苗对晚红葡萄在反复干旱胁迫和充足供水条件下的水分生理参数进行了比较研究。结果表明,晚红葡萄在反复干旱胁迫下叶片水势(Ψw)降低。但在相同相对含水量下,其Ψw比对照高。随着Ψw的下降,膨压(Ψp)逐渐降低,但在相同Ψw下,Ψp高于对照,最大Ψp比对照高0.15MPa。晚红葡萄具有渗透调节作用,但其调节能力仅有0.16MPa。反复干旱下,细胞最大体积弹性模量(εmax)增大,细胞壁刚性升高。  相似文献   
63.
ABSTRACT

Iron (Fe) deficiency is one of the major abiotic stresses affecting fruit tree crops growing in calcareous soils in the Mediterranean region. A better understanding of changes in the growth and physiological characteristics of grapevine plants during the development of Fe deficiency will help to improve Fe fertilizer management recommendations. An experiment was conducted in field conditions to determine the effects of Fe deficiency during vegetative growth on leaf photosynthesis, dry matter accumulation, pigments, and other physiological parameters. Iron deficiency considerably decreased leaf net photosynthetic rate, leaf area, and dry matter accumulation. Depressed photosynthesis and plant growth resulted in increased fruit abscission and changes in dry matter among plant tissues. The results help explain the effects of Fe deficiency on suppression of grapevine growth and yield and provide information for improving the diagnosis of Fe deficiency in grapevine production.  相似文献   
64.
The purpose of this study was to evaluate the mobility of copper (Cu) and zinc (Zn) in the profile and distribution of sandy soil fractions from vineyards. Soil samples were collected from two vineyards of different ages (14 and 30 years) and a natural field area in the south of Brazil. The chemical characteristics, Cu levels and Zn levels, were analyzed in the soils by extraction with ethylenediamine tetraacetic acid (EDTA) using the 3050B method of USEPA and by chemical fractionation. Cu and Zn were accumulated in the vineyard soils, especially in the uppermost soil layers and in the soil from the oldest vineyard. Approximately, 75% of the total Cu was extracted by EDTA, but only 30% of the total Zn was extracted by EDTA. Most of the Cu, especially in the oldest vineyard, was distributed in the mineral-associated fraction, which is characterized by low geochemical mobility, but another important part of the Cu was distributed in the soil organic matter. Most of the Zn in the soil was distributed in the residual and mineral-associated fractions, which are characterized by low mobility and have potential for causing toxicity to plants.  相似文献   
65.
欧亚种葡萄自交F1代对白粉病和霜霉病的抗性遗传   总被引:3,自引:0,他引:3  
采用田间自然鉴定、田间接种鉴定及室内离体叶圆片接种鉴定三种方法,研究了10个欧亚种葡萄品种(系)、一个欧山杂种及其493株自交后代幼苗对葡萄霜霉病及白粉病的抗性及遗传关系,同时对其自交后代抗白粉病和霜霉病的遗传趋势进行了分析.结果表明,供试品种(系)及其自交后代对霜霉病与白粉病的抗性存在极显著相关,自交后代对两病表现伴随遗传现象,初步推断这可能是由葡萄抗病基因的多效性引起.在欧亚种葡萄品种自交后代群体中,虽然90%以上都是感病性中等或高的类型,但仍能够得到一定比例(10%以下)抗病性强的类型,这为利用欧亚种葡萄品种进行自交或品种间杂交选育优质抗病新品种提供了依据.  相似文献   
66.
以欧洲葡萄‘粉红亚都蜜’为材料,利用同源克隆法获得1个NAC转录因子,命名为VvDRL1(GenBank:XP-002281816)。该基因全长840 bp,编码280个氨基酸,与‘黑比诺’葡萄中该基因的同源性为100%,但是基因组DNA序列中存在6处单核苷酸突变。瞬时转化洋葱表皮细胞进行亚细胞定位分析,VvDRL1基因主要在细胞核内表达,属于核蛋白;通过农杆菌介导的叶盘法获得稳定整合的转基因烟草,T2代转基因植株生长迟缓,株高、叶面积和叶片细胞面积约为野生型烟草的60%、34%和31%,转基因植株叶片出现向内卷曲现象,利用石蜡切片进行显微结构观察,转基因植株主叶脉上表皮下缺失2 ~ 3层厚壁细胞,且海绵组织内的空隙明显多于野生型植株。研究结果表明,VvDRL1在调控植株的形态发育方面起着重要作用。  相似文献   
67.
MicroRNAs(miRNAs)对植物抗逆及生长发育过程起着重要的调控作用,而miR164是植物特有的miRNA,它对应的靶基因主要是NAC转录因子家族。采用生物信息学方法对葡萄以及其他几个物种的miR164家族成员前体进行进化分析、前体二级结构预测、成熟序列碱基保守性分析以及在葡萄NAC转录因子家族71个成员中进行靶基因预测分析。结果表明:葡萄miR164家族成员的前体序列与双子叶植物聚在一个分支,符合进化规律;葡萄miR164家族4个成员前体序列均可形成稳定的二级茎环结构,成熟序列的碱基保守性较高;葡萄miR164家族成员对应的NAC家族靶基因有2个(GSVIVT01007982001与GSVIVT01020478001),经在NCBI进行BLAST分析,发现均与植物的根发育相关。这暗示着葡萄miR164家族与其靶基因在植物的抗逆过程中发挥重要的调控作用。  相似文献   
68.
为了获得对葡萄霜霉病具有拮抗效果的生防菌株,本研究通过平板稀释法从葡萄园土壤中分离细菌,采用离体叶片混合点样法筛选拮抗菌,并进行了田间防效试验。根据菌株的形态学及16S rDNA序列分析对其进行鉴定,并检测了菌株T3的代谢产物。在分离获得的31株细菌中,菌株T1-2和T3发酵液对葡萄霜霉病菌的室内抑制率与对照枯草芽胞杆菌CN181一致,均为100%;2次田间试验均表明,在7 d时,清水对照的病情指数增加值平均为44.3,菌株T3发酵液的病病情指数增加值平均为21.0,对葡萄霜霉病的相对防治效果为52.4%,与菌株CN181发酵液无显著差异。经鉴定,菌株T3为甲基营养型芽胞杆菌Bacillus methylotrophicus,且该菌株在代谢过程中可产生蛋白酶、纤维素酶和嗜铁素等抑菌物质。研究结果表明,菌株T3对葡萄霜霉病菌具有强烈的抑制作用,并对葡萄霜霉病具有较好的防治效果。  相似文献   
69.
The area of planting of Vitis vinifera L. cv. “Dattier de Beiruth” (DB) grafted on the SO4 (Selection OPPENHEIM 4) rootstock is significant and constantly growing in Northern Algeria. A hydroponic culture was carried out with DB to investigate the effects of potassium-magnesium (K-Mg) ratio on plant growth and mineral nutrition. Four nutrient solutions were tested on which the K-Mg ratio is variable (nutritive solution (NS)1 = 0.3 K: 3.8 Mg, NS2 = 2.1 K: 2 Mg, NS3 = 2.6 K: 1.5 Mg and NS4 = 3.8 K: 0.3 Mg). The results showed that DB was characterized by a high capacity for K uptake. No significant differences among the treatments were detected in the leaf concentrations of calcium (Ca), however Mg uptake was inhibited by increase of K: Mg in the nutrient solution. Results showed that DB is sensitive to the variation of the cation composition in the nutrient solution. Antagonism between K-Mg was apparent.  相似文献   
70.
The use of copper (Cu)-based fungicides to control diseases in vineyards can cause excessive Cu accumulation in soils. Greater Cu availability is expected in acid sandy soils with low organic matter (OM), where the risk of toxicity to plants and environment contamination is high. This study aimed to study the evolution of Cu in acid, sandy soils planted with grapevines for a period of time between 2 and 32 years. Two studies were carried out in South Brazil: in the first study, soil samples, from 19 vineyards were collected and analyzed in the first 0.2 m depth-layer for the total and available Cu. In the second study, 3 soils were selected among the previous 19 according to the age of vineyard (5, 11, and 30 year-old), and their 0.60 m-depth profile was analyzed for 5 fractions of Cu (soluble, exchangeable, mineral, organic, and residual). All the soils were classified as Ultisols. The vineyards with more than 25 years under cultivation had a mean total Cu concentration of 90 mg kg?1 in the 0–0.10 m layer. Approximately 80% of it was potentially available to plants. The greatest total and available Cu were found in the soil surface layers (0.2 m depth), where up to 75% of the total Cu is adsorbed in clay minerals and only 20% is complexed in the OM.  相似文献   
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