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21.
22.
曲周县农田土壤有效微量元素含量空间变异特征及影响因素初探 总被引:3,自引:0,他引:3
以河北省邯郸市曲周县为研究区域,采用地统计学与地理信息系统相结合的方法,对曲周县农田土壤有效微量元素铁(Fe)、锰(Mn)、铜(Cu)、锌(Zn)含量的空间变异特征及其主要影响因素进行了初步研究和探讨。结果表明:土壤有效Fe、Mn含量的最优理论模型为指数型(R2为0.887和0.553),有效Cu含量为球状模型(R2为0.988),有效Zn含量为高斯模型(R2为0.977)。土壤有效微量元素含量的空间变异程度和空间相关性由大到小依次为:Zn> Cu> Mn> Fe,Fe> Zn> Mn> Cu。从空间分布来看,土壤有效Fe、Mn、Zn含量主要处于低水平,并且土壤有效Fe、Mn、Cu含量以片状分布为主,土壤有效Zn含量呈现由西向东逐渐递减的趋势。土壤有效Fe、Mn、Cu、Zn含量与土壤有机质含量均呈极显著正相关,与土壤pH间没有显著的相关,而土壤有效Cu含量则与土壤pH间存在显著正相关。总体而言,曲周农田土壤有效Fe,Mn,Zn含量相对较低,而有效铜含量相对较高。如果种植对铁锌敏感而且需求量相对较高的作物,应该考虑Fe、Zn肥的施用。 相似文献
23.
喷施硼肥对降低板栗空苞率的研究 总被引:11,自引:0,他引:11
本文研究了微量元素硼与板栗空苞率的相互关系。试验表明,板栗空苞率与土壤中有效硼含量相关,当土壤中含硼量高于0.48ppm以上时,空苞率降低至8%以下,硼含量低于0.094ppm时,空苞率达80%以上。对板栗树的叶片和花喷施0.15~0.25%微量元素硼,可使板粟空苞率降低23~32%,明显提高产量。喷施次数以2~3次为宜,喷施时期选择在板栗展叶期、盛花期、末花期进行,但以盛花期喷施效果最好。 相似文献
24.
Sanjay K. Sharma Ankita Sharma Surinder Rana Naveen Kumar 《Journal of plant nutrition》2018,41(6):782-792
Sixty soil samples (0–0.15 m depth) collected randomly from different districts of Himachal Pradesh were used to evaluate ammonium bicarbonate-diethylenetriaminepenta acetic acid (AB-DTPA) and acid ammonium acetate-ethylene diamine tetra acetic acid (AAAc-EDTA) over standard methods for P, K, and micronutrient cations. Among Olsen P, Bray P1, AB-DTPA P, and AAAc-EDTA P, available P (kg ha?1) varied from 7.8 to 44.3, 9.5 to 61.1, 6.5 to 38.8, 10.5 to 52.1; available K (kg ha?1) among NH4OAc, AB-DTPA, and AAAc-EDTA ranged from 103.6 to 372.3, 86.6 to 364.9, and 74.6 to 362.5. In case of micronutrients cations, AB-DTPA in general, extracted more amounts as compared to DTPA alone. AAAc-EDTA correlated highly with the Olsen P. AB-DTPA-K and AAAc-EDTA-K correlated well with standard method (NH4OAc) however; AAAc-EDTA had higher correlation with AB-DTPA for K extractability. Among methods for micronutrients highest significant correlations were observed between AB-DTPA and DTPA for Cu, Fe, and Zn. 相似文献
25.
Evelyn Aline Arendt Couto Juliana Kath Juliana Aparecida Homiak Heriksen Higashi Puerari 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2016,66(4):346-352
Nematodes have difficult control and complex handling, but considering the physiological and biochemical changes that micronutrients promoting in plants, there is possibility that the supply with these chemicals increases the resistance of plants against nematodes. Thus, the present study aimed to assess the effect of the application of boron and zinc on the reproduction of Meloidogyne incognita, embryonic development and juvenile nematode hatching. Nematode reproduction was evaluated in tomato plant inoculated with 2000 eggs and treated in the aerial part with boron or zinc at the following doses: 0, 1/2, 1×, 2× and 4× the manufacturer's recommendation (100 and 30?g/L, respectively), with the plants assessed 60 days after inoculation. For assessment of embryonic development and juvenile hatching, 1?mL nematode suspension was placed in Petri dishes containing 9?mL of the same doses of boron and zinc, and assessment occurred four and eight days after incubation. Results obtained showed that boron controlled nematode population at the dose of 400?g/L and promoted juvenile hatching when used at maximum dosage on the eighth day. Zinc reduced the number of galls and the number of eggs at the dose of 60?g/L, but did not exhibit direct effect on nematode. 相似文献
26.
Saranya Kuppusamy Young-Eun Yoon Song Yeob Kim Jang Hwan Kim 《Communications in Soil Science and Plant Analysis》2017,48(13):1603-1615
Soil fertility exerts a direct influence on the essential micronutrient contents of food crops. The focus in this study was on the role that long-term inorganic fertilization (nitrogen (N), phosphorous (P) and potassium (K)) plays in increasing the micronutrient output of the paddy cropping system. After more than 45 years of inorganic fertilizer application, the combined application of fertilizers (PK > NP > NK) substantially increased As (arsenic), B (boron), Cd (cadmium), Co (cobalt), Cr (chromium), Cu (copper), Fe (iron), Mn (manganese), Mo (molybdenum), Ni (nickel), Se (selenium), V (vanadium) and Zn (zinc) density in the soil and rice grain. Optimized and continuous application of PK fertilizers increased the overall micronutrient densities in rice milling fractions (grain and bran). Micronutrient concentrations were usually the highest in bran. Both grain and bran were rich in Fe, Mn and Zn. Correlation analysis indicated that soil pH and organic matter exert a significant and direct effect on the micronutrient concentration of rice. Although long-term fertilization enhanced the proportion of micronutrients in rice grain, the levels were still much lower than the recommended dietary intake levels for micronutrients. We therefore suggest high consumption levels of brown rice (with micronutrient-dense bran layer) because they may increase the daily intake level of micronutrients and meet the nutritional requirements that people need for sound health. 相似文献
27.
基于全国282个水稻土监测点,分析土壤有效态中、微量元素含量及区域特征(东北、长三角、长江中游、西南、华南),结合丰缺标准,揭示中、微量元素丰缺程度。结果表明:东北水稻土交换性镁和有效硼含量高于其他地区,有效锌含量最低;长三角有效锰含量最高、有效硫含量最低;长江中游有效铜含量最高,有效态铁、锰和钼含量最低;西南交换性钙含量高于其他地区,有效铜含量则低于其他地区;华南有效态铁、钼含量均高于其他地区,而交换性钙、镁含量低于其他地区。中国水稻土交换性钙、镁及有效铁、锰、铜含量整体丰富;长三角和华南缺硫水稻土比例分别为42.2%和41.8%;东北、长三角、长江中游、西南和华南缺锌水稻土比例分别为75.0%、52.3%、31.9%、53.2%和10.4%,缺硼分别为38.5%、65.2%、92.2%、88.6%和78.3%,缺钼28.6%、60.4%、82.6%、42.0%和33.4%。可见,东北和长三角水稻土以缺锌为主;长江中游以缺硼、钼为主;西南以缺硼为主;华南以缺硼为主。研究可为全国和区域尺度水稻土中微量元素的管理和合理施用提供依据。 相似文献
28.
Few attempts have been made to explore the effect of Zn fertilization on the performance of medicinal plants in general and fennel in particular, under adverse conditions. This study was conducted to examine the efficacy of zinc(Zn) in correcting physiological responses of fennel to water deficit. Twelve field-grown fennel genotypes were subjected to two levels of irrigation(irrigation after 25%–35% and 75%–85% depletion of available soil water) and two levels of foliar-applied Zn(0 and 4 g kg~(-1)). Water deprivation had significant effects on all characteristics; i.e., in contrast to seed essential oil concentration, harvest index, and superoxide dismutase(SOD) and catalase activities, it led to decreases in the rest of the attributes. Varietal differences in response to drought were meaningful for most of the traits. Genotypic variations for dry mass and seed yield were consistent with differences among the genotypes in leaf water potential, relative water content, proline concentration, and chlorophyll concentrations. Zinc led to significant increases in all physiological attributes, including activation of antioxidant defense responses manifested in ascorbate peroxidase and SOD activities and carotenoid concentration. The Zn-effect tended to be more notable in drought-stricken fennel plants in a majority of the traits.Based on our findings, Zn could be considered an effective micronutrient for ameliorating, at least in part, the stressful effects of water deficit on fennel. 相似文献
29.
不同氮素形态对干旱胁迫杉木幼苗养分吸收及分配的影响 总被引:1,自引:1,他引:1
【目的】干旱胁迫是限制植物生长的重要非生物因素之一,而适宜的氮素营养可以提高植物的抗旱性。本文探讨了供应不同形态氮源对干旱条件下杉木[Cunninghamia lanceolata (Lamb.) Hook]幼苗养分吸收及分配的影响。【方法】采用水培试验,供试杉木材料为2个无性系幼苗(7–14号和8–8号),在营养液中添加10%(w/v)PEG-6000进行干旱胁迫。营养液中的氮源处理包括硝态氮、铵态氮、硝铵混合氮,氮素浓度均为4.571mmol/L,每个品种均设6个处理。培养20天后,测定了杉木幼苗根、茎、叶的养分含量及生物量。【结果】与正常水分供应相比较,干旱胁迫条件下供应铵态氮可促进叶片N、K以及茎叶P、K的吸收,供应混合氮可促进根部K的吸收;供应铵态氮可促进根、茎对Ca的吸收,对叶片Ca无明显作用。干旱胁迫对根部Fe、Mn、Cu、Zn吸收量影响显著,氮素供应不同程度地降低了干旱胁迫下各器官Mg、Fe、Mn和Cu吸收量,表现为抑制吸收,但添加铵态氮比硝态氮的降低幅度小。3个氮源处理均降低了干旱条件下根部Zn吸收量,但没有降低甚至增加了茎、叶中Zn的吸收量,说明氮营养可调节Zn在各器官间的分配,缓解干旱导致的缺锌现象。不同器官之间各养分吸收量差异显著,3个氮源处理中,N和P吸收量表现为叶>根>茎,K和Ca为叶>茎>根,Fe、Cu为根>叶>茎,Mg、Mn和Zn在各器官之间的分配规律不一。铵态氮吸收量均表现为叶>根>茎,且各器官铵态氮吸收量显著高于硝态氮,说明杉木具有明显的喜铵特性。【结论】在干旱胁迫下,氮素供应形态显著影响杉木幼苗对养分的吸收及在各器官中的分配,作用效果因家系品种和元素种类而异。总体来讲,铵态氮提高干旱胁迫下杉木幼苗养分吸收的效果好于硝态氮,杉木可以认为是喜铵植物。 相似文献
30.
Sadiq Hussain Muhammad Sharif Farmanullah Khan Hina Nihar 《Journal of plant nutrition》2018,41(12):1534-1546
Two vermicompost treatments providing 45 (V1) and 90 (V2) kg P ha?1 and mycorrhizae (M) inoculation were evaluated alone and in combinations for wheat (Triticum aestivum L.) growth and soil fertility status. The treatments included; the Control, nitrogen (N): dipotassium oxide (K2O) as basal dose (BD; 120:60 kg ha?1), N: phosphorus pentoxide (P2O5): K2O as recommended dose (RD; 120:90:60 kg ha?1), BD+Myccorhiza (BDM), BD+V1 (BDV1), BDM+V1 (BDMV1), BD+V2 (BDV2), and BDM+V2 (BDMV2). Combination of mycorrhizae and vermicompost (BDMV1 and BDMV2) significantly and maximally improved the growth, plant N, phosphorus (P), and micronutrient concentrations over the control, reduced the soil pH by 5 and 6%, increased OM by 25 and 112%, total N by 41%, and extractable P up to 200% while the extent of improvement was directly related to the content of added vermicompost. Results indicated that vermicompost at either level synergistically affected the mycorrhizae in plant nutrition as well as improved soil fertility status and soil chemical properties. 相似文献