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1.
夏季斑枯病是危害冷季型草坪草的主要病害之一,严重影响草坪质量,目前我国仍未有登记药剂防治夏季斑枯病。本研究结合室内毒力测定及田间防效检验,分析比较了嘧菌酯、稻瘟灵、丙环唑和甲基硫菌灵4种杀菌剂对夏季斑枯病菌的抑制效果,评估了药剂的田间防病效果。结果表明,丙环唑对供试的夏季斑枯病菌3株靶标菌抑制效果最佳,EC50为0.09~0.16 μg/mL;嘧菌酯次之,EC50为0.14~0.28 μg/mL;稻瘟灵和甲基硫菌灵抑制效果再次之。4种杀菌剂对夏季斑枯病害均具有较好的防控效果;其中50%嘧菌酯水分散粒剂制剂用量800 g/hm2防控效果最佳,第4次药后17 d可达99.09%;25%丙环唑乳油制剂用量2 000 g/hm2防控效果次之,第4次药后17 d为93.14%。  相似文献   
2.
In the arid regions, turfgrass cover is an integral part of landscape to protect the soil from erosion, enhance the aesthetic value, and improve the microclimate. The salinity and the scarcity of fresh water of the arid region are the major challenging factors in turfgrass production. Therefore, the need for salt tolerant turfgrass with functional quality is necessary to improve the turf performance. The detrimental effects of salinity include growth suppression, and lowered osmotic potential ultimately leading to firing of the leaf blades. In this context, the study was undertaken to determine the relative salt tolerance and growth response of turfgrass genotypes in order to recommend turfgrass cultivars that can tolerate high salinity irrigation and maintain excellent visual and functional qualities under United Arab Emirates (UAE) condition. The paspalum cultivars maintained the highest succulence percentage compared to the bermudagrass cultivars under enhanced salinity levels. The shoots count, fresh weight (FW), and dry weight (DW) were found highest in paspalum types. The chlorophyll a, chlorophyll b and the total chlorophyll content was found higher in bermuda grass types under high salinity levels. The bermudagrass cultivars showed significantly higher carotenoids, anthocyanins and proline compared to the paspalum types under salt stress condition. In the case of princess 77 and Yukon, an inherently high amount of proline was recorded which confirmed an increase up to 10,000 ppm and drastically declined beyond this concentration. Sea Dwarf paspalum and Sea Isle 2000 maintained uniformity in the proline level at all levels of salinity without significant variation. These findings point to the fact that both paspalum and bermuda types exhibited varied responses to different physiological and biochemical parameters under the saline conditions. Paspalum types have an edge over the bermudagrass in terms of shoot density, which is a potential factor in determining the high-quality turfs. Bermudagrass types can be applied in lower salinity conditions based on the responses as evidenced from the present results.  相似文献   
3.
St. Augustinegrass is well suited for lawns and commercial landscapes. While many genotypes are cross‐fertile, all cultivars are propagated vegetatively in sod production. To ensure varietal purity, development of sterile triploid hybrids by crossing tetraploid and diploid genotypes has been successfully used in other warm‐season turfgrasses. Applying this model in St. Augustinegrass would be beneficial to sod producers and turf managers who require purity for certification and uniformity for performance, respectively. This study was conducted to develop colchicine‐induced tetraploid lines of St. Augustinegrass. Seeds of cultivar ‘Raleigh’ were treated with four colchicine concentrations at four exposure times. A non‐treated control was included among the treatments. Seedlings that germinated were screened for genome size changes using flow cytometry. Line DSA 13005 and two progeny lines derived through selfing, DSA 16001 and DSA 16016, were corroborated as tetraploids (2n = 4x = 36) through chromosome counts. These lines will be used in future breeding efforts to attempt development of sterile triploid cultivars of St. Augustinegrass.  相似文献   
4.
除了教学和科研工作外,大部分美国高校对农业类学科包括草坪学科的专业师资在职责要求方面还有重要的一项-"Extension",即社会服务。社会服务的工作量因人而异,但总体来看基本都做到了"分配到人";除了专业教师,学校对于学生也要求或鼓励其参与各类校内外拓展活动。这与我国高校教师社会服务(或专业拓展)工作,以及基于此提出的"产学研"等类似的工作模式都有较大不同。草坪科学是一门新兴的学科,应用性较强,知识生产和知识创新都离不开实践。因此从学术驱动的内因和大学的价值来讲,大学的社会服务工作是极其重要的。本文简略介绍美国高校草坪科学教师的社会服务工作情况,希望能够对我国的草坪科学学科建设以及师资组建和培养提供参考。  相似文献   
5.
以可建植边坡草坪的野生荩草为材料,设置遮阴(5个水平)和干旱(4个水平)交互形成的20个组合处理,测定克隆生长性状和有性繁殖数量及生物量结构,分析不同遮阴和干旱组合处理下克隆效率指数(CEI)、繁殖分配(RA)、繁殖效率指数(REI)、繁殖指数(RI)、繁殖比率(RR)的差异,研究遮阴和干旱对荩草克隆生长和有性繁殖及权衡关系的影响,结果表明:1)遮阴和干旱对克隆子株数及克隆效率指数有显著影响,中、重度干旱和≥10%遮阴显著降低了子株数(P<0.05),干旱对CEI无影响、遮阴降低了CEI,交互作用极显著降低了基株的子株数和CEI(P<0.01)。2)遮阴和干旱对母株、子株和基株的花穗数和小花数,对繁殖器官生物量(ROB)、非繁殖器官生物量(NROB)和总生物量(TB)有显著影响(P<0.05),轻、中度干旱或10%~30%遮阴或轻度遮阴和轻度干旱组合可显著增加母株、子株、基株的花穗数和小花数,轻度干旱或10%遮阴或轻度干旱和轻度遮阴组合可显著增加TB和ROB,交互作用是影响基株花穗数和小花数、TB、ROB和NROB的主要因子,干旱对TB和NROB影响次之,遮阴对ROB影响较大。3)遮阴和干旱对RA、REI、RI和RR有显著影响(P<0.05),轻中度干旱或10%遮阴可提高基株的繁殖参数,重度干旱或≥30%遮阴度降低了有性繁殖(P<0.05),轻度遮阴和轻度干旱组合比单一处理更利于有性繁殖,轻度干旱可缓解中重度遮阴对有性繁殖的影响,繁殖参数主要受交互作用影响,遮阴次之,干旱较小。4)荩草可依据遮阴和干旱胁迫程度,进行克隆生长和有性繁殖权衡,遮阴≥30%可延长克隆生长10~34 d,中、重度干旱缩短克隆生长而促进有性繁殖,≥10%遮阴可缓解重度干旱对有性繁殖的影响(P<0.05)。5)20个遮阴和干旱组合处理下荩草均能同时维持两种繁殖方式,水分充足和全光照利于克隆生长,轻中度干旱和轻度遮阴单一或组合处理利于有性繁殖,遮阴和干旱交互影响增加了荩草的两种繁殖能力。  相似文献   
6.
混播草坪的研究现状与展望   总被引:1,自引:0,他引:1  
刘威  尹淑霞 《湖北农业科学》2011,(20):4129-4133
随着经济和社会的发展,人们对草坪的要求越来越高,因此混播草坪的发展速度在加快,应用范围在逐渐扩大。阐述了近些年混播草坪的研究现状与发展,主要介绍了混播的组合和养护管理措施对混播草坪的影响,并提出了混播草坪研究的不足之处和未来的发展前景,可为以后的混播草坪研究提供理论依据。  相似文献   
7.
8.
为了提高草业科学本科生创造性和独立性,要求学生完成喷灌系统课程设计。该课程设计特点是公式多、难记忆、抽象和难掌握。在课程设计过程中,学生经常找不到切入点,不知道各环节计算公式和各环节之间的联系。通过对多年教学过程的总结和概括,分析设计灌水定额和灌水周期、喷头布置和选型、轮灌组划分等关键环节,进一步阐明各关键环节之间的联系,以期指导学生更好掌握草坪灌溉与排水课程,达到满足草坪草用水、节约用水、形成水动景观效果、解决我国水资源紧张等目的。  相似文献   
9.
An experiment was conducted to assess the effect of foliar application of potassium silicate on Cynodon dactylon [L.] Pers., Festuca arundinacea Schreb. and Lolium perenne L. With increased salinity level, chlorophyll content and relative water content (RWC) in these three turfgrasses were reduced significantly when compared with the untreated control. Supplementary silicon (Si) ameliorated the adverse effects of salinity on chlorophyll content. Silicon treatments decreased proline at all salinity levels. Moreover, addition of Si increased shoot length and shoot number in all turfgrasses. Sodium (Na) concentration was increased in both leaves and roots of turfgrasses at high salinity level; however, Si treatment significantly reduced Na concentration in all of them. Silicon increased Potassium concentration in shoots and roots (though not significantly) in most cases. It can be concluded that Si alleviated the adverse effects of salt stress in all turfgrasses.  相似文献   
10.
草坪土壤的N2O产生途径及其对施氮肥的响应   总被引:1,自引:0,他引:1  
白龙  王跃羲  刘英  王晓红  谭冬梅 《园艺学报》2016,(10):1971-1979
硝化作用、反硝化作用和硝化细菌反硝化作用是土壤中产生N2O的主要途径.以常用的冷季型草坪草早熟禾为对象,采用气体抑制剂培养法研究了不同施氮量对草坪土壤N2O排放及其产生途径的影响.结果表明,对照草坪土壤的N2O日排放量为7.2 ~ 8.2 g· m-2.d-1,年施氮量10 g.m-2未改变草坪土壤N2O排放强度,年施氮量25、35 g·m-2处理则分别比对照增加1.52倍和1.88倍,但二者之间没有显著差异.对照草坪土壤N2O产生途径主要以异养硝化作用为主,其贡献率达65.7%,反硝化作用贡献率为34%,自养硝化和硝化细菌反硝化过程几乎不发生.年施氮量25 g.m-2时,N2O排放以硝化细菌反硝化、异养硝化和反硝化途径为主,贡献率分别为35%、35%和29%.年施氮量35 g.m2时,N2O排放来自于4个途径,其中反硝化途径占41%,自养硝化途径贡献率增加至20%.  相似文献   
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