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1.
四种化学药剂处理的悬铃木,其冬季糖和氮含量均高于对照,春季则相反;并对新梢伸长有促进,对粗度有抑制效应;其中经GA3和乙硫氨酸处理的C/N比值增大,新梢成花量增加;乙烯利和2 — 硫尿嘧啶处理的C/N比值减小,新梢成花量显著减少。从而为选用减灭悬铃木球果药剂提供理论依据。  相似文献   

2.
苹果花芽孕育机理的探讨   总被引:3,自引:0,他引:3  
花芽孕育期,以环剥、多效唑+环剥和GA3处理“红富士”苹果树,成花效应以多效唑+环剥处理为最高(+684%)。花芽孕育起动时,促花处理的短枝顶芽内IAA、ZR含量和IAA/GAs、ZR/GAs的比值均明显提高。在花芽孕育完成过程中,促花处理的短枝叶内淀粉含量、C/N比,芽内ZR、IAA含量和ZR/GAs明显提高,GAs则明显下降。  相似文献   

3.
氢醌和双氰胺对种稻土壤N2O和CH4排放的影响   总被引:14,自引:1,他引:13  
通过盆栽试验,研究了脲酶抑制剂氢醌(HQ)、硝化抑制剂双氰胺(DCD)及二者的组合(HQ+DCD)对种稻土壤N2O和CH4排放的影响.结果表明,在未施麦秸粉时,所有施抑制剂的处理均较单施尿素的能显著减少水稻生长期供试土壤N2O和CH4的排放.特别是HQ+DCD处理,其N2O和CH4排放总量分别约为对照的1/3和1/2.而在施麦秸粉后,该处理的N2O排放总量为对照的1/2,但CH4排放总量却较少差别.不论是N2O还是CH4的排放总量,施麦秸粉的都比未施的高出1倍和更多.因此,单从土壤源温室气体排放的角度看,将未腐熟的有机物料与尿素共施,并不是一种适宜的施肥制度.供试土壤的N2O排放通量,与水稻植株的NO-3N含量和土表水层中的矿质N量分别呈显著的指数正相关和线性正相关;CH4的排放通量则与水稻植株的生长量和土表水层中的矿质N量呈显著的线性负相关.在N2O与CH4的排放间,未施麦秸粉时存在着定量的相互消长关系;施麦秸粉后,虽同样存在所述关系,但难以定量化.  相似文献   

4.
萘乙酸与多效唑对茉莉成花及新梢内源激素含量的影响   总被引:4,自引:0,他引:4  
在茉莉开花前期分别使用不同浓度NAA与PP333均匀喷施于植株茎、叶片等生长部位,对其新梢与花蕾生长及其4种内源激素--生长素(IAA)、赤霉素(GA)、脱落酸(ABA)、玉米素核苷(ZR)的含量变化进行分析.结果表明:(1)NAA处理使茉莉新梢徒长,成花比对照推迟2~4 d;PP333处理的茉莉新梢矮化,而成花比对照提早2~4 d.(2)NAA处理后,茉莉新梢中IAA与ABA含量处理初期较高,后快速下降,后期稳定在较高水平;GA含量稍低于对照,ZR含量降低并稍低于对照.PP333处理后,茉莉新梢中IAA与ABA含量初期较高,而后缓慢下降;GA含量与对照一样快速上升;ZR含量在初期含量较高,后缓慢下降,但较对照稳定在较高水平.(3)PP333处理的茉莉植株新梢中ABA/IAA、GA/IAA、ZR/IAA比值在处理后迅速上升,特别是GA/IAA、ZR/IAA比值明显高于对照,而相应NAA处理的3个比值与对照无明显差异.可见,经NAA与PP333处理能明显调节茉莉新梢及花蕾生长进程,保持较高水平的内源激素GA、ZR、GA/IAA、ZR/IAA比值在茉莉新梢及花蕾生长过程中起关键作用.  相似文献   

5.
本试验探讨了不同浓度多效唑(PP333)对琯溪蜜抽枝梢生长和越冬期叶片淀粉、可溶性糖含量、束缚水/自由水比值的影响.结果表明,多效唑处理能提高越冬期叶片可溶性糖含量,增大束缚水/自由水比值,降低淀粉含量;多效唑处理使新梢长度、节间长度明显受抑制,新梢粗度增加,且随着使用浓度的增大作用增强.  相似文献   

6.
铈对黄瓜叶绿体叶绿素蛋白质复合物形成的影响   总被引:2,自引:0,他引:2  
黄瓜(Cucum issativusL.)叶片叶绿体中铈(Ce)含量随Hoagland 培养液中CeCl3 浓度的增加而增加。Ce 对黄瓜叶片Chla/b 比值的影响与光强度有关,当植株生长在强光下,对照和处理叶片的Chla/b 比值均为3.07;但在弱光下对照叶片的Chla/b 比值为2.72,而处理叶片为2.86。这说明只有在弱光下Ce才对叶片色素的组分有影响,Ce 使叶片中的Chlb 略有下降。Ce能促进叶绿体光系统Ⅰ叶绿素蛋白质复合物及110 kD多肽的形成,并使捕光叶绿素a/b 蛋白质复合物及其27 kD多肽的含量减少。  相似文献   

7.
三种类型辐射对质粒超螺旋DNA损伤的研究   总被引:7,自引:0,他引:7  
用agarose电泳和图象处理技术比较了60Coγ射线、UV及低能N+离子处理pUC19DNA超螺旋结构的损伤效应及若干自由基清除剂的保护效应。结果表明:(1)γ射线和UV照射干燥DNA的损伤显著低于水溶液样品;(2)N+离子注入后超螺旋DNA的减少(SC%)与剂量呈良好线性关系,而γ射线和UV组的SC%随剂量升高呈指数下降;(3)干燥DNAγ辐照组的D37值为820Gy,SC完全消失的剂量LD为3814Gy,LD/D37=4.65;UV照射组的相应值分别为:1.65J/cm2,7.65J/cm2,4.64;N+离子组的相应值为:3.2×1015N+/cm2,5.0×1015N+/cm2和1.56。虽然上述三种辐射的剂量单位不同,不能直接比较其相对生物学效应,但从LD与D37的比值可反映DNASC破坏的程度和终点剂量(SC%=0)的大小。从而看出,N+离子(高LET辐射)比γ射线(低LET辐射)UV(非电离辐射)对DNA损伤作用更强;(4)乙醇、甘露醇等自由基清除剂对电离辐射损伤有很强的保护作用,但对UV损伤未见明显的保护效应  相似文献   

8.
艾铁民  杨连菊 《植物研究》1995,15(3):412-412
关于“静容花属Chingyungia”的订正艾铁民,杨连菊,田建军AREVISIONOFCHINGYUNGIACEN¥AiTie—min;Yang;Lian—ju;TianJian—jun“静容花属─中国马鞭草科─新属”一文在《植物研究》15卷第2期...  相似文献   

9.
NaCl对水稻谷氨酸合酶和谷氨酸脱氢酶的胁迫作用   总被引:19,自引:1,他引:18  
在NaCl的胁迫下,水稻幼苗根和叶的谷氨酸合酶和谷氨酸脱氢酶的活性随着营养液中的NaCl浓度的升高而降低;游离NH4^+在叶中积累,在根中未见明显变化。与根相比,叶对NaCl的胁迫作用更为敏感。叶的NADH-GOGAT和NADH-GDH活性在NaCl胁迫降低的程度明显大于根。无论是否有NaCl存在,根的NADH-GDH活性明显高于叶。GS/GDH比值分析提示,对对照下,根中的NH4^存在,根的NA  相似文献   

10.
为探讨IFN-a在骨肉瘤浸润转移中的诱导调节作用。本实验采用Cel-ELISA方法半定量检测了IFN-a对体外培养的人骨肉瘤细胞系(OS-732)细胞间粘附分子-1、癌胚抗原和波形蛋白表达的诱导变化。结果显示,IFN-a对3种抗原的表达均有显著的诱导增强作用(P<0.01),且存在一定的量效关系,即IFN-a浓度<103U/ml时,ICAM-1、CEA和Vim的表达量随IFN-a浓度的增加而增加;当IFN-a的浓度>103U/ml时,其表达量随之逐渐下降。提示:IFN-a对骨肉瘤细胞有一定的诱导分化作用,在一定程度上能抑制骨肉瘤的浸润转移并且在治疗骨肉瘤中有一定的积极作用。  相似文献   

11.
In a conifer tree, such as Nordmann fir, Abies nordmanniana Spach, the leader bud and its immediate surroundings play a decisive role in crown architecture. As subapical branch buds are segregated from the leader meristem, resource allocation between ortho- and plagiotropic growth is determined. The relationship between treetop buds in young trees was studied in the natural state and after surgical removal in early July of either the leader bud (decapitation) or the subapical whorl branch buds (destipitation). The two bud types showed consistent cytokinin profile differences but similar seasonal dynamics in cytokinins and auxin (IAA). After bud excision, ZRP increased dramatically in the subapical stem within 1 h, followed by ZR within 1 week. Supernormal levels of ZR were maintained through autumn and persisted in spring in the destipitated trees, but had returned to normal in the decapitated trees. The treetop buds remaining after bud excision experienced an immediate decrease in most cytokinins, followed, however, by a large surplus later in the season. The following spring this high level persisted in the leader bud of destipitated trees, but not in whorl buds of decapitated trees. Conspicuous growth pattern changes followed from destipitation, but few from decapitation. Growth reactions suggest that resource allocation to main branch buds inhibits leader growth in normal trees, a kind of “lateral control.” Auxin and ABA content in buds and stems was largely unaffected by treatments. Data suggest that subapical leader tissues beneath the apical bud group are a primary source of cytokinin regulation.  相似文献   

12.
本文用酶联免疫检测(ELIsA)技术研究三叶-心期喷施AgNO3诱导苦瓜纯雌系完全花分化过程中花蕾与幼叶中内源激素含量变化。结果显示:喷施AgNO,后幼叶中IAA、GA,、ZR和ABA含量与喷水的相比,都是先下降后增加。AgNO3处理的花蕾中这4种激素含量在72h内没有一致变化规律,但变化幅度大于幼叶的,表明生殖器官的内源激素对苦瓜性别分化影响比营养器官的大。AgNO3处理后24-48h内,花蕾中这4种激素的含量明显低于喷水的,而其余时间则高于喷水的。此外,AgNO3处理的花蕾中ABA/IAA、ZR/I从和GA3/IAA比值也在2448h发生剧烈的变化,48h之后这些激素比值与喷水的相差不大。这些结果说明了AgNO3处理后24-48h是苦瓜纯雌系性别分化的关键时期,IAA可能是诱导纯雌系苦瓜雄性分化的关键激素。  相似文献   

13.
14.
Two manipulative experiments tested hypotheses pertaining to the correlative control exerted by nodal roots on branch development of the distal non-rooted portion of Trifolium repens growing clonally under near-optimal conditions. The two experiments, differing in their pattern of excision to manipulate the number of branches formed at the first 9-10 phytomers distal to the youngest nodal root, each found that after 20 phytomers of growth the total number of lateral branches formed on the primary stolon remained between five and seven regardless of where the branches formed along the stolon. Additional treatments established that nodal roots influenced branch development via relationships among shoot sinks for the root-supplied resources rather than through variation in the supply of such resources induced by fluctuations in photosynthate supply to roots from branches. Regression analysis of data pooled from treatments of both experiments confirmed that shoot-sink relationships for root- supplied resources controlled the branching processes on the non-rooted portion of plants. A disbudding treatment, which removed all the apical and axillary buds present on basal branches, but left other branch tissues intact, increased branch development of the apical region in the same way as did complete excision of the basal lateral branches. The apical buds and the elongation processes occurring immediately proximal to the buds were thus identified as strong sinks for the root-supplied resources. Such results suggest that branch development on the non-rooted shoot portion distal to the youngest nodal root is regulated by competition among sinks for root-derived resources, of limited availability, necessary for the processes of elongation of axillary buds and the primary stolon apical bud.  相似文献   

15.
辽东栎芽库统计:芽的命运   总被引:10,自引:3,他引:7  
孙书存  陈灵芝 《生态学报》2001,21(3):385-390
植物体是一个构件集合体,植物的枝系伸展可由芽库出生率、死亡率的统计学过程来分析。在东灵山地区,应用随机枝取样法调查了辽东栎芽的命运,并对其与枝长、叶数、果数等的关系进行了统计分析。结果表明:(1)辽东栎的芽或保持休眠状态,或死亡后脱落,或分化为营养枝、生殖枝(包括雄花枝、雄花序、雌花枝和两花枝)等;(2)不同生境中芽的命运不同,生活在林窗中的幼树上的芽分化为具有生殖功能的枝条的比例显著高于郁闭林中的幼树,而与成熟个体接近;(3)芽的命运还受其它因子的影响,如上层枝条上、或叶数多的长枝上的芽分化为生殖枝的可能性大于其它的芽,另外还发现结实枝的枝长、枝上叶数都明显高于非结实枝。  相似文献   

16.
A field experiment was conducted during the summer of 1988 to test the hypothesis that water deficit affects the abscisic acid (ABA) and indole acetic acid (IAA) concentrations in cotton (Gossypium hirsutum L.) flower buds in ways that predispose young fruits (bolls) that subsequently develop from them to increased abscission rates. Water deficit had little effect on the ABA content of flower buds but increased the ABA content of flowers as much as 66%. Water deficit decreased the concentrations of free and conjugated IAA in flower buds during the first irrigation cycle but increased them during the second cycle. Flowers contained much less IAA than buds. Water deficit slightly increased the conjugated IAA content of flowers but had no effect on the concentration of free IAA in flowers. Because water deficit slightly increased the ABA content but did not decrease the IAA content of flowers, any carry-over effect of water deficit on young boll shedding might have been caused by changes in ABA but not from changes in IAA.  相似文献   

17.
In two branched plants ofImpatiens balsamina with intact apex and leaves floral buds are induced only in the branch which is either exposed to 8-h (inductive) photoperiods or receives GA3 treatment if maintained under 24-h (non-inductive) photoperiods. GA3 induces floral buds on the treated branch even if the leaves on that branch are removed, showing that while leaves are essential for photoperception, these are not neoessary for GA3 to cause induction. The effect of the inductive photoperiods or GA3 treatments to a branch is not transmitted to the other branch which is treated with water and is maintained under non-inductive photoperiods even when the latter is defoliated but is transmitted if the apioal or both the apical and axillary buds on the branch receiving inductive photoperiods or GA3 treatment are excised. It, therefore, appears that the existence of strong sinks in the form of axillary and apical buds on the treated branch prevents the transmission of photoperiodic as well as GA3 effects to the other branch in this plant.  相似文献   

18.
以南方红豆杉幼茎段和茎尖为外植体,以wPM为基本培养基,单一添加不同浓度的KT、TIBA、ZT和6-BA进行芽诱导培养。结果表明:各自添加0.4mg·L-1KT、3.0mg·-1TIBA、0.1mg·L-1 ZT和0.01mg·L-1 6-BA时的芽诱导率最高。培养50d的试管微芽中紫杉醇和10一去乙酰基巴卡亭III(10.DABIII)的积累量比天然南方红豆杉嫩枝高2倍以上,试管微芽中10一DABIII比紫杉醇高,且二者均随芽诱导率的增加而增加,当芽诱导率达最高时亦达到最高。TIBA所诱导芽短而粗壮。  相似文献   

19.
Hg2+污染对莼菜冬芽幼叶细胞超微结构伤害的研究   总被引:3,自引:0,他引:3  
报道了Hg^2+污染对莼菜冬芽幼叶毒害引起的叶片受害症状和叶肉细胞的超微结构变化。冬芽在Hg^2+浓度5mg/L处理15d时,叶片开始褪绿,腺毛收缩扭曲,粘液减少,细胞中高尔基体消失,核糖体减少,线粒体出现解体。在相同处理时间中,随着Hg^2+浓度增加,细胞出现质膜收缩,胞间连丝断裂,核仁裂解成多个小核仁,叶绿体膨胀,类囊体解体。在Hg^2+浓度15mg/L时,细胞核解体,细胞死亡。经观察,Hg^  相似文献   

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