反相高效液相色谱法测定黄瓜和梨中阿维菌素B1a残留   总被引：2，自引：0，他引：2  

张红艳  王玉红  赵玉珍  王成菊  李学锋  邱立红 《农业环境科学学报》2007,26(3):1085-1087

利用反相高效液相色谱法研究建立了蔬菜（黄瓜）与水果（梨）中阿维菌素残留量的测定方法。样品采用甲醇提取，二氯甲烷萃取，经弗罗里硅土柱净化，最后用甲醇定容。色谱柱为C18不锈钢柱（25cm×4.6mm，10μm），流动相甲醇＋水=90＋10（V＋V），流速为1.0mL·min^-1，检测波长为245nm，采用外标峰面积进行定量。结果表明，阿维菌素在0.05～5.00mg·L^-1范围内呈良好的线性关系（r=1.0000），方法的添加回收率范围为82.99%～92.23%，变异系数为2.31%～4.15%，最小检出浓度为0.001mg·kg^-1，能够满足对该农药在黄瓜和梨中残留分析的要求。  相似文献   

杨凌地区四个欧美鲜食葡萄品种综合性状比较     

吴婧  龚倩  丘赛  王华 《北方园艺》2012,(18):48-50

在陕西杨凌地区对"信农乐"、"巨玫瑰"、"户太八号"和"巨峰"4个欧美鲜食葡萄品种进行了为期1a的综合性状调查研究。所有品种均露地栽培并采用果实套袋技术,调查其物候期、果实经济性状以及抗病性等。结果表明:4个品种的综合性状在杨凌地区表现优良,细节方面存在一定的差异,其中"巨峰"和"户太八号"表现最优,"信农乐"次之,"巨玫瑰"相对较差。  相似文献   

滑动平均法和分形理论结合的稻瘟病发病特性研究     

邱靖  吴瑞武  杨毅  彭莞云 《农业网络信息》2015,(3)

通过文献分析稻瘟病发生与气象有着密切的关系,利用滑动平均法将云南省凤庆县稻瘟病病情指数分解成趋势及气象波动病情指数,分析结果表明趋势病情指数总体呈下降趋势,而气象波动病情指数具有一定的混沌特性,并利用相空间延拓及G-P算法验证了气象波动具有一定混沌特性。  相似文献   

栽培槽大小对日光温室架式栽培番茄生长发育、水肥利用和产量品质的影响     

张海  李冬  胡莹莹  魏珉  杨凤娟  史庆华  王秀峰 《中国蔬菜》2016,1(8):45-49

利用封闭式循环供液高架栽培系统,研究了栽培槽大小(横切面宽度×深度:20cm×10cm,20cm×15cm,20cm×20cm)和钵栽(直径12cm×高10cm,基质容积1L)对架式栽培番茄(3穗果摘心)生长发育、水肥利用及产量品质的影响。结果表明:与钵栽相比,槽栽促进番茄植株生长,增加产量,但开花和采收时间延迟,果实品质下降,水肥利用效率降低;随着栽培槽体积的增大,植株生长旺盛,干物质积累量增加,但水肥利用效率降低,果实品质下降,不同大小栽培槽处理间水分利用效率和单株产量差异不显著。综合产量、品质及水肥利用效率等指标,番茄架式栽培槽大小以20cm×10cm为宜。  相似文献   

新疆十种野生药用植物核型分析     

牛凯  许正  丘佳丽  张力鹏  陈成彬 《北方园艺》2016,(8):159-163

以新疆伊犁新源县的4科10种药用植物为试材,采用植物染色体标本制备的去壁低渗方法,研究了染色体数目并进行了核型分析。结果表明:大麻(Cannabis sativa L.)2n=20=12m+8sm、苦豆子(Sophora alopecuroides L.)2n=36=26m+8sm+2st、毛牛蒡(Arctium tomentosum Mill.)2n=36=6m+28sm+2st、牛蒡(Arctium lappaL.)2n=36=8m+26sm+2st、千叶蓍(Achillea millefolium L.)2n=36=26m+10sm、牛至(Origanum valgare)2n=30=12m+18sm、菊苣(Cichorium intybus L.)2n=18=12m+6sm、新疆鼠尾草(Salvia deserta Schang)2n=14=4m+10sm、草原糙苏(Phomis protensis Kar)2n=22=12m+6sm+4st、乌拉尔甘草(Glycyrrhiza uralensis Fish)2n=16=6m+10sm,其染色体数目与前人报道一致。千叶蓍(Achillea millefolium L.)、牛至(Origanum valgare)、新疆鼠尾草(Salvia deserta Schang)3种植物为首次报道。  相似文献   

毛竹笋竹两用林改建大径竹林技术初报     

唐昌贻  邱永华  刘仙 《浙江林业科技》2012,32(5)

通过3年来对朝北的山坡或山岙地的笋竹两用林林分采取增加竹林密度和选粗壮的竹笋留养新竹的技术培育毛竹大径竹材,结果表明:新竹平均胸径达11.76 cm,比实施前提高了0.93 cm;胸径≥12 cm立竹株数达55.8％,比实施前提高了近18百分点；林分立竹竹材产量比实施前增加34.3％；胸径≥12 cm立竹竹材产量提高了14.8％；每度新竹立竹产值比实施前增加36.6％.  相似文献   

玉米单粒机械播种及栽培技术要点   总被引：1，自引：0，他引：1  

赵庆华 《种业导刊》2010,(12):28-28

近年来单粒播种在玉米生产上已有较大面积应用，成为精准农业的组成部分，单粒播种没有多余的苗争水争肥，不需间定苗，不存在伤根现象，能保证养分被苗充分利用，促进玉米前期的早生快发，保证苗齐苗壮，既提高了玉米的综合抗性，又减轻了病害的发病几率。现将玉米单粒机械播种及栽培要点作以介绍。  相似文献   

华中世纪星数控系统车床程序屏蔽的使用方法     

王建  裘敏浩 《湖南农机》2012,(11):130-131

在华中世纪星数控车床上用G71粗车复合循环程序加工凸凹件的配合过程中,因凸凹配合件尺寸过大或者过小,需要再加工来满足配合要求,此时若屏蔽G71粗车复合循环程序段,之后加工精加工程序段就能满足配合要求,这样就能减少空运行加工时间,从而大大提高工件加工效率。  相似文献   

Water and Energy Consumption by Agriculture in the Minqin Oasis Region   总被引：1，自引：0，他引：1  

LI Cheng  WANG Yue  QIU Guo-yu 《中国农业科学(英文版)》2013,(8):1330-1340

Water used in agriculture consumes much energy, mainly due to pumping water for irrigation, but the water-energy nexus is always neglected in arid and semi-arid areas. Based on hydrological observation data, irrigation data and socio- economic data over the past 50 yr, this study has derived a detailed estimate of greenhouse gas (GHG) emissions from agricultural water use in the Minqin Oasis. Results show that the decreasing water supply and increasing demand for agriculture has caused severe water deficits over the past 50 yr in this region. The groundwater energy use rate rose by 76% between 1961 and 2009 because of the serious decline in groundwater levels. An increase in pump lift by an average 1 m would cause GHG emission rates to rise by around 2%. Over the past 10 yr, the GHG emissions from groundwater accounted for 65-88% of the total emissions from agricultural water. GHG emissions for diverted water varied from 0.047 to 0.074 Mt CO 2 e as the water input increased. Long distance conveyance and high pump lifts need more electricity input than groundwater abstraction does. Government policies have had a favorable effect on total emissions by reducing water abstraction. But groundwater depletion, exacerbated by a growing population and an expansion in arable land, remains the principal energy-water nexus challenge in the region. In response to the increasing water-energy crisis, energy-saving irrigation technology, matching to cost efficiencies, and better coordination between different infrastructural agencies could be feasible ways of rendering the water and energy sectors more sustainable over the long term.  相似文献   

General Nexus Between Water and Electricity Use and Its Implication for Urban Agricultural Sustainability:A Case Study of Shenzhen, South China     

LI Wen-jiang  LI Lin-jun  QIU Guo-yu 《中国农业科学(英文版)》2013,(8):1341-1349

Although water and energy resources are well-recognized concerns regarding economic and social development sustainability, little specific research has focused on both water and energy problems at the same time. This study analyzed the water and electricity-use patterns in Shenzhen, South China during 2001-2009. A curve regression method was used to examine the relationship between water and electricity use per gross domestic product (GDP) in Shenzhen and its three sectors, i.e., agriculture, industry & construction, and residential life & services. Results showed that agriculture only covered less than 10% of water and electricity use in Shenzhen, while industry & construction and residential life & services accounted for more than 90% of water and electricity use in Shenzhen, which coincided with the city’s industrial structure. The water and electricity use per GDP in agriculture was the biggest among three sectors in Shenzhen during 2001-2009, which means inefficiency of water and electricity use in agriculture. Due to transitioning to advanced materials and manufacturing, both water and electricity use per GDP in industry & construction decreased during 2001-2009 and their utilization efficiencies gradually increased over time. The same held true for those in residential life & services transformed toward modern business, creative culture, finance services, etc. Derived from the survival of the fittest in competing for limited water and electricity resources, agriculture in Shenzhen has been gradually substituted by industry & construction and residential life & services, with much higher efficiencies of water and electricity use. And traditional agriculture will not be sustainable in the process of urbanization and industrialization, except high-tech intensive agriculture with low water and energy cost. Furthermore, by means of curve regression, we found that there was a significant quadratic relationship between water use per GDP and electricity use per GDP in the entire city and its three sectors. Suitable industrial transformation and advancement was a very effective way to save water and energy for modern cities. This can provide some reference for systematic planning and design of water and electricity allocation and use in agriculture, industry & construction and residential life & services in a city.  相似文献