月季切花不同品种衰老征兆及瓶插寿命的比较   总被引：12，自引：2，他引：10  

白双义  刘青林 《园艺学报》2001,28(4):364-366

 对11 个月季切花品种在瓶插期间的开花指数、花径变化、衰老征兆进行了观测, 并研究了这些指标与瓶插寿命的关系。结果表明: 不同品种其开花指数、花径变化及瓶插寿命存在明显差异; 月季切花衰老的征兆有萎蔫、落瓣、弯颈、褪色、蓝变、褐变、焦边,且这些衰老征兆在瓶插末期同时出现或先后出现。  相似文献   

Expression of a lipoxygenase encoding gene (BoLOX1) during postharvest senescence of broccoli     

María Eugenia Gomez-LobatoPedro M. Civello  Gustavo A. Martínez 《Postharvest Biology and Technology》2012,64(1):146-153

Lipoxygenases (LOX) belong to a large family of plant enzymes that catalyze the hydroperoxidation of polyunsaturated fatty acids. Most of them are expressed during senescence and contribute to membrane deterioration and biosynthesis of jasmonic acid, a known senescence enhancer. In this work, we cloned a fragment of a gene encoding a LOX from broccoli (BoLOX1). The analysis of the sequence revealed that BoLOX1 is closely related to other LOX from higher plants. Furthermore, we analyzed the expression of BoLOX1 and detected a larger increase during postharvest senescence. A slight increase of total lipoxygenase activity was also found during senescence. In other sets of experiments, broccoli heads were treated with plant hormones, such as cytokinin and ethylene, as a way to assess the effect of such compounds on the expression of BoLOX1. Cytokinin treatment delayed the increase of BoLOX1 expression and lipoxygenase activity whereas ethylene accelerated both processes. Also, several postharvest treatments were applied in order to delay senescence in broccoli florets and to evaluate their effects on BoLOX1 expression. Samples treated with modified atmosphere, hot air, UV-C or white light showed a delay in chlorophyll degradation and degreening. In most cases, the treatments also delayed the increase of BoLOX1 expression, reaffirming the relationship between the expression of this gene and senescence. However, treatments like modified atmospheres and visible light markedly increased lipoxygenase activity, which suggests a lack of correlation between BoLOX1 expression and lipoxygenase activity.  相似文献   

Characterization of a Novel Gain-of-Function Spotted-Leaf Mutant with Enhanced Disease Resistance in Rice     

CHEN Ting  CHEN Zheng  Atul Prakash SATHE  ZHANG Zhihong  LI Liangjian  SHANG Huihui  TANG Shaoqing  ZHANG Xiaobo  WU Jianli 《水稻科学》2019,26(6):372-383

We here reported the identification and characterization of a novel gain-of-function spotted-leaf 26(Spl26) mutant from an ethylmethylsulfone(EMS)-induced rice cultivar IR64. Spl26 displayed reddishbrown lesions that firstly appeared on the leaf tips at the early tillering stage and spread gradually downward to cover the whole leaf blades that wilted subsequently. The lesion development was lightdependent under natural conditions. Spl26 exhibited impaired photosynthetic capacity with decreased chlorophyll content and lowered photosynthetic parameters which ultimately led to the poor performance of agronomic traits. Severe cell death occurred in Spl26 in accompany with increased malonaldehyde level and membrane ion leakage rate, elevated reactive oxygen species(ROS) accumulation, altered ROS scavenging activities, increased DNA fragmentation and decreased soluble protein levels. Defense responses were activated in Spl26 with enhanced resistance to rice bacterial blight, up-regulation of defense response genes and altered endogenous hormone levels. The spotted-leaf phenotype is controlled by a single dominant nuclear gene localized to a 305 kb region between RM5490 and In Del42 on the short arm of chromosome 7. The data suggested that Spl26 is a novel gain-of-function spotted-leaf mutant with enhanced bacterial disease resistance and immunity-associated premature leaf senescence and would provide the basis for cloning of the target gene.  相似文献   

Pollination-induced oxidative stress in floral organs of Cymbidium pendulum (Roxb.) Sw. and Cymbidium aloifolium (L.) Sw. (Orchidaceae): A biochemical investigation     

Lucky K. Attri  Harsh NayyarRavinder K. Bhanwra  Anju Pehwal 《Scientia Horticulturae》2008

A perusal of literature showed that a little is known about the metabolic changes related to senescence in orchid flowers. It was observed that unpollinated flowers of Cymbidium pendulum (Roxb.) Sw. remained fresh for 20 days and senesced within 8 days after pollination (DAP), while that of Cymbidium aloifolium (L.) Sw. took 18 days when unpollinated but showed senescence in 7 DAP. A higher level of electrolyte leakage was recorded in all the floral organs of pollinated flowers in both the species. There was a concomitant increase in levels of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂); indicators of oxidative damage, in all the organs for both the species. Ascorbic acid, on the other hand, decreased significantly. Higher amount of electrolyte leakage, MDA and H₂O₂ content were recorded in C. pendulum as compared of the other species while the ascorbic acid, on the other hand, was observed to be decreased and this decrease was more in C. pendulum than C. aloifolium suggesting a higher oxidative damage to the floral organs in the former species than the latter. TIBA, i.e. tri-iodobenzoic acid (an auxin inhibitor; 0.25 μM) and silver nitrate (ethylene inhibitor; 0.25 μM) application to pollinated flowers partially prevented the elevation of oxidative damage and consequently senescence suggesting the involvement of these hormones in governing these changes in orchid flowers. Comparatively, AgNO₃ was more effective than TIBA in delaying senescence.  相似文献   

两品种小麦叶片衰老过程中清除H2O2能力的差异   总被引：8，自引：0，他引：8  

冯晴  徐朗莱 《作物学报》1998,24(6):828-833

引入Ｒｈｔ３矮秆基因的宁矮１号小麦叶片,在全展初期,ＣＡＴ,ＡＰＸ和ＧＲ活力琢ＡｓＡ,ＧＳＨ含量比其亲本苏麦３号高,而在全展后期则不如苏麦３号,这与叶片的光合功能变化相对应。宁矮１号叶片中Ｈ２Ｏ２的累积早于苏麦３号,与其叶片较早地进入衰老相一致。较低浓度的外源Ｈ２Ｏ２对叶片衰老早期的ＣＡＴ,ＡＰＸ和ＧＲ活力有正调节作用、但随着衰老程度的加深,这种调节作用减弱。  相似文献   

生长调节物质对花生叶片衰老调控的初步研究   总被引：8，自引：1，他引：7  

李向东  王晓云 《中国油料作物学报》1998,20(4):52-55,60

结荚期喷施０．０１ｍＭ赤霉素,０．０５ｍＭＮ＾６－苄基腺嘌（６－ＢＡ）,５ｍＡ脯氨酸,３ｍＭ抗坏血酸,１０ｍＭ甘氨酸,６ｍＭ乙烯利等生长调节物质均可提高花生叶片叶绿素含量和净光合速度,增加叶片可溶性蛋白持含量,降低叶片内丙二醛积累量,提高叶片超氧化物歧化酶,过氧化物酶和过氧化氢酶活性,延缓花生叶片衰老,提高产量。  相似文献   

不同覆盖方式对烤烟成熟期根系活力和叶片衰老特性的影响   总被引：10，自引：0，他引：10  

杨志晓  张小全  毕庆文  汪健  黎根  邱妙文  杨铁钊 《华北农学报》2009,24(2)

以烤烟K326为试材,在大田条件下研究了前膜后草、地膜覆盖、无覆盖3种不同覆盖方式下烤烟成熟期根系活力和叶片衰老特性变化.结果表明,与常规栽培相比,前膜后草覆盖方式下,烤烟成熟期根系活力显著提高,叶片叶绿素和可溶性蛋白质含量较高,叶片保护酶SOD、POD、CAT活性较强,MDA含量较低,烤烟衰老速度缓慢,延长烤烟成熟期,提高烤烟经济性状;而地膜覆盖方式下,烤烟根系活力降低,叶片叶绿素和可溶性蛋白质含量急剧下降,叶片保护酶SOD、POD、CAT活性下降,烤烟膜脂过氧化程度加剧,烤烟衰老速度加快.  相似文献   

不同激素对早稻剑叶和根系衰老特性影响的研究     

孙刚  张文学  李祖章  刘光荣  谢金水 《江西农业学报》2009,21(2)

水培条件下探讨了在水稻齐穗过程中,不同种类激素对水稻剑叶和根系中活性氧代谢和产量的影响。结果表明;不同种类的外源激素对水稻衰老特性的影响不尽相同。在水稻齐穗时,叶片和根系的丙二醛含量之间的差异并不大。喷施不同外源激素7 d后,与对照相比较,激动素可降低叶片中丙二醛含量40.4%,使叶片中的O2-产生速率降低到33.56μg/gFW.min。三十烷醇可使叶绿素含量提高58.3%,并使O2-产生速率降低到34.79μg/g FW.min。喷施三十烷醇的水稻叶片和根系中CAT酶的活性最高,分别比同时期清水对照的高出25.9%和65.9%。喷施14 d后,三十烷醇可提高叶绿素含量136.5%,可使剑叶中O2-产生速率降低到34.79μg/g FW.min,叶片和根系中CAT活性仍高出对照212.1%和158.8%。虽然三十烷醇延缓水稻衰老的作用很显著,但赤霉素可使水稻结实率提高4.1%,6-苄基腺嘌呤的增产幅度却是最大。  相似文献   

秸秆还田对旱地小麦旗叶衰老及产量的影响   总被引：2，自引：0，他引：2       下载免费PDF全文

李国清  石岩 《农学学报》2012,2(7):1-4

为了研究秸秆还田对旱地小麦的影响,通过田间试验的方法,研究了秸秆还田对旱地小麦旗叶衰老及产量的影响。试验结果表明,秸秆还田处理的小麦旗叶超氧化物歧化酶(SOD)活性、可溶性蛋白含量均比未还田的要高,而过氧化物酶(POD)活性、丙二醛(MDA)含量均比未还田处理的要低。在花后20天后,秸秆还田处理的小麦旗叶SOD活性、可溶性蛋白含量均比秸秆未还田的要高,并且增加的速度在加快;而POD活性、MDA含量均比秸秆未还田处理的要低,并且降低速度同时也在加快。秸秆还田可以维持较高的保护酶体系,减少膜的破坏。在产量结构及产量上,秸秆还田处理的穗数、穗粒数、千粒重等明显比未还田处理的高,产量也有显著提高,比秸秆未还田处理高10.07%。因此,秸秆还田处理利于缓解旱地小麦旗叶的衰老,对旱地小麦的产量有提高作用。  相似文献   

两优培九剑叶衰老过程光合膜功能及蛋白质复合物的变化     

叶露幻  沈唯军  郑宝刚  宋涛  陈国祥  吕川根 《作物学报》2013,39(11):2030-2038

为探讨高产杂交稻两优培九在衰老过程中,剑叶光合膜蛋白质复合物的含量变化规律及其与光能吸收、转化、传递的关系,以大田栽培自然衰老剑叶为材料,利用活体叶绿素荧光动力学技术,并结合类囊体膜蛋白质复合物蓝绿温和胶电泳分析。结果表明,两优培九剑叶叶绿素含量、光合性能、类囊体膜蛋白稳定性等都在抽穗期达到顶峰,随后开始衰退,在扬花期、灌浆期尚保持较高水平,而进入籽粒成熟阶段衰退明显;随着衰老进程,光合膜蛋白质复合物有序非同步降解,稳定性为LHCII > PSIIcore > PSIcore > ATPase & Cyt b₆/f > LHCI;PSI和PSII蛋白和相应电子传递活性的稳定性及下降幅度差异较大;衰老过程叶绿素a/b的不断下降与相对于反应中心更稳定的捕光天线有关,剑叶生长后期LHCII维持高水平保持了叶片对光能的吸收,并可能在调节光系统间能量分布和协助过剩能量耗散中起重要作用。  相似文献