花生叶片衰老中多胺代谢酶活性及游离多胺含量变化（简报）

花生叶片衰老过程中,多胺代谢酶精氨酸脱羧酶（ADC）、鸟氨酸脱羧酶（ODC）和多胺氧化酶（PAO）活性逐渐下降,而腐胺（Put）含量迅速上升,精胺（SPm）、亚精胶（Spd）含量下降,致使衰老期间Put／（Spd＋Spm）迅速上升。     

多效唑对月季切花衰老的影响

本文研究了用多效唑处理的月季切花在瓶插期间的形态、生理变化,结果表明,多效唑能明显地缓解月季切花水分胁迫,改善体内水份平衡,促进切花开放,增加花朵鲜重和花径,抑制花瓣溶质外渗,延缓切花呼吸速率的下降和蛋白质降解的速率,从而延缓切花衰老。     

多胺与植物衰老关系研究进展

多胺作为生理活性物质与植物衰老关系密切。本文综述了近十年来多胺对衰老的调控作用,从调节细胞膜的理化性质,生物大分子合成作用以及多胺与乙烯的关系等方面阐述了多胺延缓衰老的机制,比较了多胺和影响衰老的植物激素在信号转导过程中的作用。     

多效唑及6-BA对油橄榄氧自由基代谢和叶片脱落的影响

在我国长江中上游引种区,油橄榄落叶很严重,从１０月初就开始脱落,１１月初至１２月底为落叶高峰期,即使一年生叶片当年也开始脱落,叶片的寿命短于２年。而在原产地地中海沿岸地区,叶片寿命为３年,落叶高峰期为３～４月,叶片寿命的缩短影响了油橄榄开花座果和果实发育〔１〕。因此延缓油橄榄叶片衰老脱落对促进开花座果和果实发育显得特别重要。近年来超氧自由基（Ｏ２）在植物衰老脱落中所起的作用引起人们广泛注意。Ｏ２可通过启动自由基的链反应及其它类型的再氧化等产生羟基自由基（ＯＨ·）、单线态氧和过氧化氢。这些活性…     

豇豆叶片衰老过程中多胺氧化酶活性的变化（简报）

豇豆幼苗的连体和离体叶片衰老过程中多胺氧化酶（PAO）活性与叶绿素和蛋白质的含量都呈下降趋势,它们的降幅依次是：PAO活性大于叶绿素含量大于蛋白质含量;用氨基胍抑制离体叶圆片PAO活性,不能延缓叶绿素和蛋白质的含量下降。     

多胺与植物衰老关系研究进展

多胺作为生理活性物质与植物衰老关系密切。本文综述了近十多年来多胺对衰老的调控作用,从调节细胞膜的理化性质、生物大分子合成作用以及多胺与乙烯的关系等方面阐述了多胺延缓衰老的机制,比较了多胺和影响衰老的植物激素在信号转导过程中的作用。     

多效唑对螟虫的影响

<正> 多效唑(MET)是近几年来大力推广的一种植物生长延缓剂,自1987年在我县引进,至1989年在晚稻秧田施用面积已达35％以上。它具有提高秧苗素质,促使秧苗矮化、粗壮,提早和增加分蘖,增强秧龄弹性,缓和季节矛盾,易拔秧,移栽后不落黄,节约用种量,增产显著等效果。 由于施用多效唑改变了禾苗形态和生理机能,使原不利螟虫发生的秧苗期,变为有利,致使晚稻秧苗期虫口密度大幅度上升,已成为下一代的主要虫源田之一。笔者于1988～1989     

多效唑及6-BA对油橄榄氧自由基代谢和叶片脱落的影舷

在我国长江中上游引种区,油橄榄落叶很严重,从10月初就开始脱落,11月初至12月底为落叶高峰期,即使一年生叶片当年也开始脱落,叶片的寿命短于2年.     

Distribution of Cu2+-diamine oxidase during ontogeny of seedlings of Vigna radiata cultivars

Activity of Cu2+-diamine oxidase (DAO; E.C.1.4.3.6.) was measured in Vigna radiata (L.) Wilczek cultivars K851, MH8320 and Pusa Baisakhi in light and in dark during ontogeny of seedlings. DAO activity was always the highest in cv. K851. In both light and dark grown seedlings maximum DAO activity was detected on day 2 after germination. Thereafter, in light grown seedlings it declined consistently upto non-detectable levels. In dark, DAO activity was higher than in light and it had the second maximum on day 7 following a similar declining pattern as observed for the light grown seedlings. The DAO activity was higher in a shoot apex alongwith leaves than in roots and shoot axis. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effect of gibberellic acid on carnation flower senescence: evidence that the delay of carnation flower senescence by gibberellic acid depends on the stage of flower development

Gibberellic acid at concentrations of 10^–5 M and 10^–4 M delayed the senescence of cut carnation flowers, when applied continuously via the stem, to flowers between the closed brush and fully open stages of development. Older flowers with reflexed petals were unresponsive. Treatment with paclobutrazol, an inhibitor of GA biosynthesis, prevented tight buds from opening fully, reduced the longevity of partially open flowers, but was ineffective when applied continuously to fully open flowers. Gibberellic acid-treated flowers did not show simultaneous petal inrolling, a known indicator of senescence, and the time to complete petal drying was extended. Gibberellic acid modified the climacteric ethylene rise in a manner consistent with the extension of longevity. These results provide evidence for a correlative role of gibberellins in flower development.Abbreviations GA₃ gibberellin A₃ - GLC gas liquid chromatography     

Polyamines and carnation flower senescence: Endogenous levels and the effect of applied polyamines on senescence

The polyamines putrescine and spermine were effective in delaying the senescence of carnation buds, but were ineffective when applied to flowers of which the petals had already opened, and were 90° with respect to the stem. Higher levels of endogenous putrescine were detected in the open flowers than in the buds, and this may explain the negative effect obtained when polyamines were applied to open flowers that were picked for commercial distribution.Abbreviations AOA amino-oxyacetic acid - AVG amino-ethoxyvinyl-glycine - SAM S-adenosyl methionine - STS silver thiosulphate     

花生衰老进程的研究

通过对鲁花11号和辐8707 2个高产花生品种的衰老进程研究表明：花生衰老具有地上部（叶片）渐进衰老和整株衰老的双重特点。花生从始花至花后60d左右为地上部（叶片）渐进衰老期：此期主茎高、侧枝长、分枝数、主茎、侧枝绿叶数、叶面积、茎、叶干重迅速增加,并接近或达到最大值,主茎及侧枝基部叶片逐渐由下向上开始衰老死亡,饱果开始出现,根系活力、固氮酶活性逐渐升高至接近最大值,始花后60－90d为整株缓衰期,此期地上部茎叶生长基因停止,逐渐开始衰老死亡,主茎、侧枝绿叶数开始减少,生殖体（荚果）干重迅速增长,根系活力、固氮酶活性缓慢降低;始花后90d以后称为整株速衰期,此期主茎、侧枝绿叶迅速减少,地上部迅速衰老死亡,生殖体（荚果）干重缓慢增长,根系活力、固氮酶活性迅速降低。地上部（叶片）渐进衰老期与开花及大量荚果形成相对应,整株缓衰期伴随着荚果迅速增重,整株速衰期与荚果缓慢增重一致。     

Effect of paclobutrazol on water stress-induced ethylene biosynthesis and polyamine accumulation in apple seedling leaves

Ethylene biosynthesis and polyamine content were determined in [(2RS,3RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pentan-3-ol] (paclobutrazol) pre-treated and non-treated water-stressed apple seedling leaves. Paclobutrazol reduced water loss, and decreased endogenous putrescine spermidine content. Gibberellic acid (GA) counteracted the inhibitory effect of paclobutrazol on polyamine content. Paclobutrazol also prevented accumulation of water stress-induced 1-aminocyclopropane-1-carboxylic acid (ACC), 1-(malonylamino)cyclopropane-1-carboxylic acid (MACC), ethylene production and polyamines in apple leaves. α-Difluoromethylarginine (DFMA), but not α-difluoromethylornithine (DFMO), inhibited the rise of putrescine and spermidine in stressed leaves. S-Adenosylmethionine (SAM) was maintained at a steady state level even when ethylene and the polyamines were actively synthesized in stressed apple seedling leaves. The conversion of ACC to ethylene did not appear to be affected by paclobutrazol treatment.     

外源多胺对盆栽花生盐胁迫的缓解作用

为探讨外源多胺对花生(Arachis hypogaea)抗盐性的影响, 以盆栽花生‘花育22’为试验材料, 通过叶面喷施1 mmol·L^-1腐胺(Put)、1 mmol·L^-1亚精胺(Spd)、1 mmol·L^-1精胺(Spm)的方法, 研究多胺对150 mmol·L^-1 NaCl胁迫下盆栽花生的缓解作用。结果表明, 与对照(CK)相比, 盐胁迫显著抑制了花生植株的生长与荚果产量, 降低了叶绿素含量和抗氧化酶活性, 丙二醛(MDA)含量、叶片相对电导率增加; 在盐胁迫下, 叶面喷施Put、Spd、Spm处理均可有效促进花生植株的生长, 提高了超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的活性, 增强植株抗氧化能力, 显著降低了花生叶片相对电导率和MDA的积累量, 从而缓解盐胁迫对质膜的过氧化伤害; 提高了叶绿素含量, 促进了植株高度的生长与分支数增多, 增加了干物质积累量, 从而提高了花生荚果产量; 其中, Spm处理引起的变化幅度大于Spd和Put处理。研究结果说明, 多胺有利于花生幼苗在盐胁迫下活性氧代谢和光合色素含量的提高, 促进花生植株的生长, 降低盐胁迫对花生植株的抑制作用, 且Spm处理的效果最好。     

多效唑对不同品质类型花生产量、品质及相关酶活性的影响

选用高蛋白品种KB008（KB008）、高脂肪品种花17(H17)和高油酸/亚油酸（O/L）品种农大818（818）,在大田栽培条件下,研究了盛花后期叶面喷施多效唑(PBZ)对不同品质类型花生产量、品质及相关碳、氮代谢酶活性的影响.结果表明：喷施PBZ显著增加了3种品质类型花生荚果产量,原因是增加了单株结果数,降低了千克果数而提高了双仁果率.喷施PBZ不同程度地提高了3种类型花生籽仁脂肪和可溶性糖含量,降低了蛋白质含量,显著增加了高脂肪品种H17的O/L值.PBZ使高O/L值品种818的脂肪含量增加显著,同时其蛋白质含量显著降低,而对其他两品种的蛋白质和脂肪含量影响较小.喷施PBZ均降低了3种类型花生结荚期叶片硝酸还原酶（NR）活性及结荚期和饱果期叶片谷氨酰胺合成酶和谷氨酸脱氢酶活性,818的3种酶活性降低幅度最大,KB008和H17的酶活性降幅较小;喷施PBZ均降低了3种类型花生结荚期和饱果期叶片谷草转氨酶和谷丙转氨酶活性.说明氮代谢酶活性的降低是喷施PBZ降低3种类型花生籽仁蛋白质含量的主要原因.喷施PBZ均提高了3品种结荚期和饱果期叶片蔗糖合成酶和磷酸蔗糖合成酶活性,其中显著提高了818的2种酶活性,而对KB008和H17的活性提高不显著;喷施PBZ提高了3品种结荚期和饱果期的磷酸烯醇式丙酮酸羧化酶和1,5-二磷酸核酮糖羧化酶活性,其中对818在结荚期的活性提高最显著,对H17活性提高较小.碳代谢酶活性的增强是喷施PBZ提高花生籽仁脂肪含量的生理基础.