期刊文献+
共找到103篇文章
< 1 2 6 >
每页显示 20 50 100
梨树二度开花的发生及补救措施
1
作者 余宏章 《农村百事通》 2012年第18期46-46,共1页
梨树在10月上中旬经常会有不同程度的二度开花现象,树势明显较弱,这将大大影响下年梨的产量和品质。所谓的梨树二度开花,也叫梨树二次生长,是指梨树上的部分枝条在秋季重新抽梢长叶,潜伏在枝条上的花芽被打破休眠,开出花朵,这部分花朵... 梨树在10月上中旬经常会有不同程度的二度开花现象,树势明显较弱,这将大大影响下年梨的产量和品质。所谓的梨树二度开花,也叫梨树二次生长,是指梨树上的部分枝条在秋季重新抽梢长叶,潜伏在枝条上的花芽被打破休眠,开出花朵,这部分花朵只会消耗养分,不能结出果实,因而也称无效花。 展开更多
关键词 梨树 补救 现象 二次生长 打破休眠 枝条
下载PDF
晚霜期苹果花体温度与果园气温变化特征及其关系分析 被引量:3
2
作者 徐蕊 卫建国 +3 位作者 张磊 朱永宁 王静 李红英 《经济林研究》 北大核心 2021年第1期68-74,共7页
【目的】探究晚霜期苹果花体温度与果园气温变化特征,为给现有的苹果花期霜冻指标及其在其他相关研究中的精准运用提供科学依据。【方法】利用树体监测仪自动监测晚霜期无霜冻日和霜冻日不同冠层花体温度和果园气温,并对监测数据进行对... 【目的】探究晚霜期苹果花体温度与果园气温变化特征,为给现有的苹果花期霜冻指标及其在其他相关研究中的精准运用提供科学依据。【方法】利用树体监测仪自动监测晚霜期无霜冻日和霜冻日不同冠层花体温度和果园气温,并对监测数据进行对比分析。【结果】花体温度和果园气温均呈单峰且同步的变化趋势。无霜冻日和霜冻发生前后距地面1.5和2.0 m处的冠层花体温度相近,距地面1.5和2.0 m处的果园气温相近;霜冻发生时,距地面1.5和2.0 m处的冠层花体温度相近;距地面2.0 m处的果园气温高于距地面1.5 m处的果园气温,温差在1.0℃以内。无霜冻日,花体温度日平均值比果园气温偏高0.67~1.95℃,霜冻日及其前一日偏高2.39~3.55℃,霜冻日后4天偏高1.14~1.60℃。其中,霜冻发生前的降温时段,花体温度比果园气温高1.5~4.53℃,霜冻发生时高2.16~6.37℃,当花体温度降至0℃以下时,其温度比果园气温高2.5~4.8℃,平均高3.49℃,其中74.4%的时间段花体温度比果园气温高3.0~4.0℃。建立晚霜期苹果花体温度与果园气温的关系模型,无霜冻日夜间逐时关系拟合程度最好,霜冻发生期间每10 min花体温度与果园气温的关系拟合程度较好,平均绝对误差为0.59℃;当花体温度低于0℃时,气温越低,花体温度的计算误差则越大。【结论】分析晚霜期富士苹果花体温度与果园气温的关系,结合两者的关系模型可以为苹果花期霜冻灾害防御与灾后评估评价提供科学依据。 展开更多
关键词 苹果 晚霜期 体温 果园气温
下载PDF
植物生长调节剂促进蝴蝶兰二度开花的实验
3
作者 李志文 《生物学教学》 北大核心 2008年第7期59-59,共1页
蝴蝶兰(Phalaenopsis amabilis)花色美丽多姿,花朵造型独特,形似蝴蝶,花数多而且排列有序,花期长达三个月,易于栽培,因而深受人们的喜爱。由于组织培养技术的广泛应用,规模化、商业化生产使得蝴蝶兰走进寻常百姓家,成为节日... 蝴蝶兰(Phalaenopsis amabilis)花色美丽多姿,花朵造型独特,形似蝴蝶,花数多而且排列有序,花期长达三个月,易于栽培,因而深受人们的喜爱。由于组织培养技术的广泛应用,规模化、商业化生产使得蝴蝶兰走进寻常百姓家,成为节日喜庆常见的观赏性花卉。尤其是春节,蝴蝶兰更是得到人们的喜爱。根据南方人的习惯,花期过后往往把植株丢弃。蝴蝶兰虽然已经开过花,但是花梗内还含有休眠的花芽,如果将0.5%~1.0%的6-BA和0.125%~0.25%的GA3混合涂在采花后的花梗的伤口上,植株可再度开花。利用将要丢弃的蝴蝶兰探究学习植物激素调节相关教学内容,为学生提供切实有效的学习资源, 展开更多
关键词 植物生长调节剂 蝴蝶兰 实验 组织培养技术 商业化生产 6-BA 教学内容
下载PDF
紫薇二度开花有新法
4
作者 罗举毅 《花木盆景(下半月)》 2001年第10期39-39,共1页
紫薇的花芽是在当年的新生枝上形成,当年开花。只要掌握了这一规律,采取不同的技术措施,可使其二度开花。我采用推迟翻盆法,可使紫薇盆景二度开花,花期延长,与早春翻盆相比,有其优越性,其具体作法是:早春发芽前,选择树形优美,具有一定... 紫薇的花芽是在当年的新生枝上形成,当年开花。只要掌握了这一规律,采取不同的技术措施,可使其二度开花。我采用推迟翻盆法,可使紫薇盆景二度开花,花期延长,与早春翻盆相比,有其优越性,其具体作法是:早春发芽前,选择树形优美,具有一定观赏价值的桩景,暂时不作翻盆,只作一次蓄枝2cm~5cm 的重剪。 展开更多
关键词 紫薇 紫薇盆景 观赏价值
下载PDF
果树一年二度开花并非异事
5
作者 袁晓霞 《林业月报》 1997年第12期21-21,共1页
关键词 果树 一年二 防止措施 施肥 整表修剪
下载PDF
糖人男神,度我低眉花开
6
作者 侯利明 《黄河.黄土.黄种人》 2017年第5期28-29,共2页
父亲以吹糖人为生,他仿佛拈花的佛,手法变幻间,就能吹出各种各样的糖人。
关键词 散文 文学作品 现代文学 《糖人男神 我低眉开》
下载PDF
紫薇花期延长技术研究 被引量:5
7
作者 王军 《现代农业科技》 2013年第13期168-168,171,共2页
紫薇花期延长技术研究结果表明,在紫薇第1次开花后对其残花枝进行短截修剪,确实能够促使紫薇二度开花,且整株开花量较多;但应把握好花后修剪时间,必须在第1次开花后(尚未结果前)及时短截残花枝,若延误了修剪时间则会导致紫薇不能二度开花。
关键词 紫薇 期延长 短截修剪
下载PDF
怎样使梅开二度
8
作者 聂传圣 《专业户》 2004年第2期17-17,共1页
梅花一年二度开花,并非是什么吉祥或灾涡之征兆,只是与当年不正常的气候状况有关,人工促成同样也可使梅开二度。具体做法是:7月上旬,将梅花盆移至避雨处,让其断水,自然干燥,约三天后,便会出现叶枯干而失水现象,
关键词 人工促成 自然干燥 浇水 休眠 施肥
下载PDF
Dwarfing effects of plant growth regulators on narcissi 被引量:3
9
作者 任旭琴 梁宏伟 +1 位作者 陈伯清 季美云 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期339-341,共3页
The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001. The results showed that the regulators could inhibit the growths of height and leaves of narcissi. O... The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001. The results showed that the regulators could inhibit the growths of height and leaves of narcissi. Of the four regulators, the dwarfing effects of paclobatrazol (PP333) and uniconazole (S3307) on narcissi were better than those of chlorocholine (CCC) and dimethyl amino-sussinamic acid (B9). All of the regulators did not have significant effect on the root length. Moreover, the time of flowering was later for the narcissi treated with regulators than that of the control to a certain extent, and the range delayed was from 2 days to 19 days. The correlation analysis results showed that there was a significant correlation between the time of flowering and the concentrations of regulators. The ornament value of narcissi was obviously improved by using the regulators. 展开更多
关键词 Narcissus tuzetta var. chinesis Roem Plant growth regulators PP333 S3307 B9 CCC
下载PDF
Studies on Powder Scattering Regularities of Male Flowers of Walnut in Xinjiang
10
作者 宁万军 廖康 +3 位作者 王国安 张强 刘娟 黄闽敏 《Agricultural Science & Technology》 CAS 2013年第12期1747-1749,1763,共4页
[Objective] The aim was to find out the regularities of powder scattering about walnuts' male for improving walnut yield and quality. [Method] The powder was collected by the method of gravity glass slide, and the re... [Objective] The aim was to find out the regularities of powder scattering about walnuts' male for improving walnut yield and quality. [Method] The powder was collected by the method of gravity glass slide, and the regulation of powders scattering of 'Xinxin2' and "Wen185' which were the two main cultivated varieties of walnut in Xinjiang were studied. [Result] The results showed that the male inflo- rescence powder lasted for around 10 d, and centralized scatter powder was about 4 d, when walnut male at the daily mean temperature was from 20 to 24℃. Gen- erally, the large powder shedding amount was in east, south and central position of crown, in the range of 19 to 27 ℃, and the optimal temperature of powder scatter- ing was 20 to 23 ℃. [Conclusion] The pollens scattering regularities of walnut is closely related to temperature. With a favorable temperature, powder scattering per- forms outstandingly. 展开更多
关键词 XINJIANG WALNUT TEMPERATURE Male inflorescence Powder scattering
下载PDF
Analysis of Flavone Content in Honey of Pomegranate Flowers
11
作者 卢焕仙 梁铖 +4 位作者 张学文 赵洪木 余玉生 宋文菲 王艳辉 《Agricultural Science & Technology》 CAS 2013年第1期166-168,共3页
[Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as... [Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as per- spectrophotometry method with acetone as an extractant and rutin as a control. [Result] The average content of flavones in honey of pomegranate flowers was at (2.36±1.36)mg/100 g in 2011 and significantly higher than that in 2012 at (1.71± 0.53)mg/100 g. Analysis was conducted on flavones content in different batches and the results indicated that content of flavones in honey in different batches changed from increasing to decreasing, namely, the content was maximal in peak flowering stage, followed by late flowering stage and initial flowering stage. [Conclusion] The research provides references for development, use and function exploration of the honey of pomegranate flowers. 展开更多
关键词 EXTRACT Honey in pomegranate flowers Total flavones Spectrophotome- try ANTHESIS
下载PDF
Study on Spatial Distribution Pattern of Thrip (Odentot hrips lati) on Alfalfa (Medicago sativa) 被引量:1
12
作者 赵丽丽 王普昶 +1 位作者 刘玉良 陈彦希 《Agricultural Science & Technology》 CAS 2011年第7期990-993,共4页
[Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots wit... [Objective] The aim of this study was to reveal and analyze the spatial distribution pattern of thrip(Odentot hrips lati) on alfalfa(Medicago sativa).[Method] Within alfalfa plantation areas,experimental plots with the sizes of 10×10,10×20,10×30,20×30,20×40,20×80,30×30,30×40,30×50,40×40,40×50,40×80 and 50×50 m2 respectively were set up in the randomly selected sampling sites of 1 m ×2 m in size.During bud-emerging period and florescence period of alfalfa in the experimental plots,the number of thrips was counted and their distribution pattern was measured using XU Ru-mei's method.[Result] During bud-emerging period of alfalfa,the spatial distribution of thrips assumed an elliptic shape sized of 40×30-40×40 cm2 at horizontal level and that presented an ascending-falling trend of tress density down from the top at vertical level.During the florescence period of alfalfa,it showed a homogeneous distribution or randomly distributed pattern at horizontal level and a falling trend of tress density from the top to the apex to the root at vertical level.[Conclusion] Our results provide theoretical basis for field selection of insect-resistant alfalfa varieties. 展开更多
关键词 THRIPS Different degree Distribution pattern ALFALFA
下载PDF
小叶丁香播种育苗技术 被引量:4
13
作者 李玉琴 《农业科技通讯》 2009年第2期149-149,共1页
小叶丁香又名四季丁香,属于木犀科丁香属。产于辽宁,西北、华北及华中有分布,黑龙江省有栽培。该植物喜光耐寒,几乎无病虫害,抗旱能力较强.枝条柔细,树姿秀丽,花色鲜艳,且一年二度开花,为园林中优良的花灌木。适于种在庭院、... 小叶丁香又名四季丁香,属于木犀科丁香属。产于辽宁,西北、华北及华中有分布,黑龙江省有栽培。该植物喜光耐寒,几乎无病虫害,抗旱能力较强.枝条柔细,树姿秀丽,花色鲜艳,且一年二度开花,为园林中优良的花灌木。适于种在庭院、居住区、医院、学校、幼儿园或其他园林、风景区。可孤植、丛植或在路边、草坪、角隅、林缘成片栽植,也可与其他乔灌木尤其常绿树种配植。由于它叶小,耐修剪,近年来北安、哈尔滨等黑龙江许多城市用作绿篱、修剪成球形。绿化效果非常好,因此园林绿化中用量也非常大。 展开更多
关键词 丁香属 播种育苗技术 小叶 园林绿化 黑龙江省 抗旱能力 常绿树种
下载PDF
Influence of Xenia Effect on the Fruit of Watermelon 被引量:5
14
作者 李红斌 《Agricultural Science & Technology》 CAS 2009年第5期36-37,共2页
[ Objective] To study the influence of xenia effect to the fruit of watermelon. [ Method ] Self-crossing and crossing by inbreeding of more generation female parent, male parent :07-10-2-3-3( tall spherical, golden ... [ Objective] To study the influence of xenia effect to the fruit of watermelon. [ Method ] Self-crossing and crossing by inbreeding of more generation female parent, male parent :07-10-2-3-3( tall spherical, golden yellow peel with thin lines, red flesh), 07-32-2-3-5( tall spherical, green peel with greenish thick lines, red flesh), 07-33-1-2-3(tall spherical, green peel with greenish thin lines, red flesh) [ Result] It was found that Fo (07-10-2-3-3 × 07-32-2-3-5) and Fo (07-10-2-3-3 × 07-33-1-2-3) seed ripening was accelerated, and the sugar degree increased by 1.7 - 2.4%, and the flesh became crisp.[ Conclusion] The result demonstrates watermelon has xenia effect. 展开更多
关键词 WATERMELON POLLEN Xenia effect Sugar degree
下载PDF
Vitality and storage condition of Syringa pollen 被引量:6
15
作者 周莉 罗凤霞 +1 位作者 代力民 张惠华 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期67-70,共4页
The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The result... The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The results indicated that the pollen vi-tality (81.5%) of Syringa villosa was the highest among the seven tested species, followed by S. microphylla and S. meyeri, and that of S. oblata var. affinis was the lowest. The low temperature was the best condition for storage of pollen of Syringa, and the most proper temperature for the storage was 0-2 癈. The storability of S. microphylla was the best of all, and it could be stored over 60 days at the temperature of 0-2 癈, next was S. villosa and S. meyeri. 展开更多
关键词 SYRINGA POLLEN VITALITY Storage condition
下载PDF
Effects of Spark Ignition Engine Operating Parameters on Its Cyclic Variation ——Modeling and Simulation
16
作者 纪常伟 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期332-336,共5页
An engine cyclic variation model has been built by using the residual gas temperature for the n th cycle as the input of the model, through constant pressure intake process, adiabatic compression process, constan... An engine cyclic variation model has been built by using the residual gas temperature for the n th cycle as the input of the model, through constant pressure intake process, adiabatic compression process, constant volume combustion process, adiabatic expansion process, adiabatic blow down process and constant pressure exhaust process to approximate the thermodynamic processes in the cylinder, finally the residual gas temperature for the ( n+1) th cycle can be estimated. Because of the adding of engine operating parameters such as engine speed, spark advance, equivalence ratio, intake air pressure, intake air temperature to the model, effects of these parameters on cyclic variation can be estimated quantitatively. Since residual gas temperature fluctuation between cycles reflects the circumstances of engine cyclic variation, parameters to which residual gas temperature is sensitive are most likely used as the means to control cyclic variation. Model simulation shows that for the nearly stiochiometric mixture, cyclic variation is not obvious or even quite stable, but for the lean mixture, under the circumstances of partial load and larger spark advances, engine cyclic variations occur chaotically or with bifurcation. 展开更多
关键词 cyclic variation MODELING residual gas temperature spark ignition engine
下载PDF
忆东山
17
作者 李白 《俄语学习》 2017年第6期1-1,共1页
关键词 东山 度花 蔷薇 谁家 还自 月落
下载PDF
Lamp Distribution Design for Adjustment of Florescence in Floral Production
18
作者 王峰 李抒智 +1 位作者 马可军 庄美琳 《Agricultural Science & Technology》 CAS 2013年第11期1629-1631,共3页
[Objective] The aim was to introduce characters of light sources and select the optimal lamp scheme for floral production in greenhouses. [Method] With chrysanthemum cuttings as materials, HPSL, energy-saving fluoresc... [Objective] The aim was to introduce characters of light sources and select the optimal lamp scheme for floral production in greenhouses. [Method] With chrysanthemum cuttings as materials, HPSL, energy-saving fluorescent lamp, and LED agricultural lamp were made use of to carry out field tests in order to compare practical effects according to light characters of different lamps and plant growth de-mands. [Result] The results show that LED lamp performed the best of the three in practical use. LED square lamp designed in bat-wing shape would be the most ben-eficial for lamp distribution in a greenhouse. [Conclusion] LED agricultural lamp is the most popular currently, for it is energy saving and easy for operation. 展开更多
关键词 HPSL Energy-saving fluorescent lamp LED agricultural lamp ILLUMINATION Power density Chrysanthemum cuttings
下载PDF
三言两语话《中国仲裁》
19
作者 高菲 《中国对外贸易》 2003年第A02期7-7,共1页
一年一度花相似,岁岁年年人不同。整日忙忙碌碌埋头于案文之间,猛回首,瞧那日历已翻到了创办《中国仲裁》的第三个年头,窗外柳树已绽出新绿。三年了,一切都在迅速地改变,日新月异。
关键词 度花 证券纠纷 仲裁制 仲裁机构 仲裁程序 一事不再理 法律内容 仲裁实践 正面回答 市场经济规则
下载PDF
浣溪沙·泳 棉
20
作者 陈业正 《中国棉麻流通经济》 2008年第1期22-22,共1页
关键词 浣溪沙 雅韵 度花
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部