梨实生树不同发育区的叶片细胞学研究

采用显微分光光度计和显微图像分析仪比较研究了8年生梨实生树(Pyrus pyrifliaNakai)童区和成年区叶片细胞核 DNA含量、RNA含量和细胞、细胞核面积大小的差异。梨实生树从童区向成年区转变后,叶片内细胞核DNA含量上升,细胞内RNA合成加强,细胞和细胞核面积增大;同时,叶肉组织结构分化程度提高,叶面积增大,叶片加厚。     

大血藤叶片生化成分的动态变化

对自然条件下大血藤叶片生化成分的动态变化进行了研究。结果表明;大血藤叶片可溶性糖,淀粉和总糖含量的动态变化有相同的趋势。在叶片生长季节早期含量较低。随着叶片的生长发育,其含量逐渐上升。至8月达到最大值后逐渐下降,叶片总糖含量与日均净光合速率的季节变化呈极显著的正相关,在整个生长季节中,可溶性糖含量比淀粉高,大血藤叶片总蛋白含量季节性变化呈单峰曲线,在展叶初期含量较低;随后迅速上升,至8月达到最大值后逐渐下降,叶片总糖含量与日均净光合速率的季节变化呈极显著的正相关。在整个生长季节中,可溶性糖含量比淀粉高。大血藤叶片总蛋白含量季节性变化呈单峰曲线,在展叶初期含量较低;随后迅速上升,在6月初达到最大值后逐渐下降,落叶前降至最低占,可溶性蛋白质含量的季节性变化曲线与总蛋白含量基本相似,DNA含量在叶生长初期大幅度上升,至6月达到高峰后迅速下降,以后基本趋向稳定,RNA在叶生长初期有所上升,峰值也出现在6月,以后缓慢下降,到9月降至最低值,在落叶前又有所回升,总核酸含量的季节变化与RNA变化相似,RNA/DNA比值在生长季节中出现3次高峰,大血藤叶片总黄酮含量季节性变化呈“双峰”型,第1高峰期在开花期的5月。第2高峰期在秋季的9月份。     

3种薯蓣属植物珠芽糖类含量变化与茎叶生长的关系

以山药、日本薯蓣和黄独3种薯蓣属植物为材料,研究珠芽育苗中其茎叶生长与珠芽内的干物质、淀粉、可溶性糖、还原糖含量和淀粉酶活性变化的关系.结果表明: 3种薯蓣在茎蔓生长过程中珠芽内的干物质和淀粉含量均逐渐降低.山药和黄独的珠芽可溶性糖含量在茎蔓生长初期不断增加,随着茎蔓节数继续增加又逐渐降低,而还原糖含量在叶片展开前不断增加,叶片展开后又急剧降低;日本薯蓣珠芽的可溶性糖和还原性糖含量随着茎蔓节数增加逐渐上升,但保持相对较低水平.3种薯蓣珠芽内α-淀粉酶活性均强于β-淀粉酶,其在茎蔓和叶片生长中发挥重要作用.研究发现,薯蓣珠芽内淀粉主要在α-淀粉酶作用下转化分解为还原糖和可溶性糖,从而为茎蔓和叶片生长提供能量,且还原糖含量与叶片生长的关系更为密切.     

梨实生树童区和成年区顶端分生组织的细胞学研究（简报）

梨实生树童区技梢顶端分生组织中中央区、周缘区和肋状分生组织的细胞核中DNA含量分别低于、无差异于和高于成年区枝梢顶端分生组织中各相应区域,童区顶端分生组织中这三个区域的细胞中RNA含量都比成年区低。童区与成年区顶端分生组织的细胞核面积无差异,细胞面积的差异只出现在中央区。     

湖北海棠阶段转变过程中几种同工酶变化研究

采用聚丙烯酰胺凝胶电泳法、研究了湖北海棠1年生实生菌（S1）、4年生（S4）、14年生（S14）实生树及4年生成年芽嫁接树（G4）不同高度叶片的过氧化物酶（POX）、细胞色素氧化酶（COD）、酯酶（EST）、乙醇脱氢酶（ADH）同工酶的变化。结果表明：多年生实生树随着高度的增加,POX Rf 0.56、0.60,COD Rf0.50,EST Rf0.09、0.15、0.75、0.77,ADH Rf0.76等几条酶带呈现,邮童区和成年区各自特有的同工酶带,随高度童区特征酶带消失或成年区特征酶带的高度均保持在150－200cm之间,同当年植株开花最低位置相同,S4、S14童区与S1同工酶谱带完全一致,S4、S14成年区与G4同工酶谱基本保持一致,G4同工酶谱并未随高度增加而发生变化,四种同工酶可以作为阶段转变的指标。S4、S14童区与成年区谱带的差异是高度的结果,高度是湖北海棠阶段转变的重要因子。     

光周期诱导甘蔗花芽分化及成花逆转过程中生理代谢的变化

以两个在自然条件下难开花的甘蔗品种‘ROCl6’和‘ROC22’为材料,研究经光周期诱导甘蔗花芽分化和成花逆转过程中叶片碳水化合物和可溶性蛋白质含量的变化。结果表明,未分化前,两品种经光周期诱导后叶片可溶性总糖、淀粉和蛋白质含量与对照相比无明显变化;从花芽分化诱变期开始,两品种叶片可溶性总糖、淀粉和蛋白质含量迅速增加,明显高于对照（未分化）。随着花芽进一步分化,其叶片可溶性总糖、淀粉含量逐渐降低并低于对照,处在一个较低的水平,蛋白质含量始终高于对照。成花逆转植株在花芽分化前期叶片可溶性总糖、淀粉和蛋白质含量也高于对照,但低于正常抽穗开花植株;之后随着花芽分化的停止,其叶片可溶性总糖、淀粉含量一直保持较稳定的水平,仅蛋白质略有降低。说明甘蔗花芽分化期间大量的基因表达并且合成各种蛋白质的过程需要消耗大量的碳水化合物。     

豇豆摘叶对产量与生理生化指标的影响

为明确摘除叶片对豇豆植株的落花率、成荚率、产量及生理生化指标的影响效果,以鄂豇豆6号为试验材料,在植株不同的生育时期摘除不同程度的叶片,统计了豇豆植株的落花率、成荚率及产量的高低,研究了蕾、花和荚的丙二醛、可溶性糖、多聚半乳糖醛酸酶、纤维素酶等指标的变化情况。结果表明,在初花期摘除1/3的叶片,与未摘叶对照相比,落花率降低了14.95%,成荚率增加了10.01%,产量增加8.37%。在盛花期不同程度的摘叶处理,落花率均高于对照,其中,轻度的摘叶处理(1/4)将成荚率提高了40.11%,对应的产量提高了5.23%。落蕾、落花和落荚中的丙二醛含量、多聚半乳糖醛酸酶活性、纤维素酶活性与新鲜的蕾、花和幼荚相比都升高,可溶性糖含量均降低。故在生殖生长时期,摘除适量叶片,可以促进落花率的降低和产量的提高,同时,植株脱落材料的生理指标也发生相应的变化。     

硒对镉胁迫下水稻幼苗生长及生理特性的影响

采用溶液培养 ,研究不同浓度的硒和镉处理对稻苗的株高、叶片干重、叶绿素、还原糖、叶片丙二醛含量以及保护酶 SOD、POD、CAT活性的影响。结果表明 ,镉胁迫下稻苗矮化 ,镉毒害使叶片失绿 ,干重降低 ,还原糖含量下降 ,叶片 MDA含量增加 ,POD活性增强 ,而 SOD、CAT活性降低 ;硒可减轻镉对水稻的毒害 ,表现为 :减轻镉胁迫对株高增加的抑制 ,提高叶绿素含量 ,增加叶片干物质积累 ,提高叶片还原糖含量 (Cd0 .5 mg/ L加 Se 0 .1 0～ 0 .5 0 mg/ L例外 ) ,降低 MDA含量与 POD活性 ,提高 SOD、CAT活性     

丛枝菌根真菌对青杨抗溃疡病生物量和抗病酶活性的影响

本研究以青杨Populus cathayana 1年生扦插苗为试验材料,接种丛枝菌根真菌（arbuscular mycorrhizal fungi,AMF）异形根孢囊霉Rhizophagus irregularis和杨树溃疡病菌聚生小穴壳菌Dothiorella gregaria,测定AMF对青杨根茎叶生物量,丙二醛（MDA）、脯氨酸和茎部纤维素含量,超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、多酚氧化酶（PPO）、几丁质酶、多聚半乳糖醛酸酶和果胶甲基酯酶等抗病酶活性的影响。结果表明,接种AMF可以增加青杨根茎生物量,增加茎纤维素含量来增强树势,降低溃疡病发病率;接种AMF能够显著降低感病杨树茎部和根系MDA含量,增加叶片和根系脯氨酸含量,提高根茎叶PPO活性、茎SOD活性和叶片CAT活性;接种AMF前期可以提高茎和根系几丁质酶和β-1,3-葡聚糖酶活性,也可以提高叶片和茎多聚半乳糖醛酸酶、果胶甲基酯酶活性,接种病原菌条件下AMF效果更加显著。结论认为,AMF通过积累脯氨酸,降低MDA含量,提高SOD、CAT和PPO活性,增强杨树抗溃疡病能力;同时也可提高多聚半乳糖醛酸酶和果胶甲基酯酶活性来抑制病原菌菌丝的生长,减弱菌丝的扩展能力,增强杨树抗病性。     

海仙花开花和衰老过程中的生理变化（简报）

海仙花开花初期，花内还原糖、蛋白质、氨基酸含量增高，而ｐＨ值较高，花青素含量却很低，从淡红花开始，ＰＨ值开始降低，而花青素含量急剧增加，还原糖与蛋白质含量亦降低，花萎蔫时达最低，而氨基酸含量却一直呈上升趋势，过氧化物酶活性开始时缓慢增国，花萎蔫时迅速升高。花相对透性值的变化与此类似。     

Effect of second-leaf removal or kinetin treatment on the nucleic acid metabolism of senescing first seedling leaf of barley

1. Changes in nucleic acid metabolism in first seedling leaves of barley plants during aging (from 7 to 27 days) were followed, and the effect of continual removal of the second leaf and basal meristem or of treating the first leaf with 20p.p.m. kinetin on these changes was examined. During aging of the first seedling leaves the ribosomal RNA, DNA and soluble RNA declined, with ribosomal RNA showing the most rapid fall. This was, however, accompanied by increased incorporation of ³²P into RNA, which reached its peak on the fifteenth day. 2. Second-leaf removal partially suppressed first-leaf senescence as judged by retarded chlorophyll and nucleic acid decline and by a decreased extent of RNA labelling. Treatment with kinetin, however, did not prove effective. 3. No significant differences in the sucrose-gradient pattern of ³²P-labelled nucleic acids or in the ³²P-labelled nucleotide composition of RNA fractions during aging or during the two treatments were noted, except for a decrease in CMP content of soluble RNA during aging. 4. The results demonstrate that important changes in RNA metabolism are associated with leaf senescence.     

莲胚发育与核酸,蛋白质含量的变化

莲胚发育达到最大鲜重(开花后21d)前,胚轴和子叶的DNA,RNA都持续增长。开花13d后,蛋白、淀粉等贮藏物质显著积累,核酸增长速度加快。成熟胚轴的DNA和RNA含量很高,而子叶中积累大量的淀粉、可溶性糖和蛋白质。发育前期胚乳的生长速度较快,开花后16d左右鲜重和物质积累达到高峰。胚生长后期胚乳逐渐败育,贮藏物质和结构物质都减少,膨大的子叶逐步取代了胚乳的地位。 莲胚生物大分子物质含量的模式属于双子叶植物类型。讨论了莲胚细胞多倍化的问题。     

Nucleic Acid and protein changes in relation to cold acclimation and freezing injury of korean boxwood leaves

Quantitative and qualitative differences in nucleic acids of Korean boxwood (Buxus microphylla var. Koreana) leaves were determined by methylated albumin kieselguhr chromatography at different levels of cold hardiness. During cold acclimation there was an increase in RNA, mainly ribosomal RNA, with little or no change in DNA. The increase in ribosomal RNA was closely paralleled by an increase in water soluble and membrane bound proteins. As cold hardiness increased, ribonuclease activity declined.     

高温春化逆转对甘蓝体内核酸类物质含量的影响

甘蓝早熟品种‘8398’长至6片真叶和中熟品种‘京丰’长至7片真叶时进行绿体春化处理,前者处理18d和后者处理23d时用37℃高温进行春化逆转后检测植株体内核酸的结果表明,核酸、DNA和RNA含量以及RNA/DNA比值显著下降,而正常春化的植株则均呈缓慢上升趋势。     

Changes in Nucleic Acid Metabolism of Excised Barley Leaves During Senescence and the Effect of Kinetin on these Changes

The changes in the amount, rale of synthesis and the nucleotide composition of different RNA fractions in excised barley leaves floated on water or kinetin (10 mg/l) in the dark were examined. In excised leaves floated on water all nucleic acid components declined and these declines were retarded by kinetin. Barley leaves floated on water showed a stimulation of ³²P incorporation into various RNA fractions within 48 hours followed by a decline after 96–144 hours. The leaves floated on kinetin, however, showed an even higher incorporation of ³²P into UNA by 48 hours which remained at a comparatively higher level throughout the experiment. In spite of the above changes in RNA synthesis significant differences in the ³²P sucrose gradient profiles or in the ³²P nucleotide composition of UNA from water and kinetin floated leaves were not noted. The results of this study show that important changes in nucleic acid metabolism occur during the early stages of leaf senescence and that alterations in nucleic acid metabolism during senescence and during kinetin treatment may involve quantitative and only subtle qualitative changes.     

Nucleic Acid Metabolism in Germinating Onion: I. Changes in Root Tip Nucleic Acid during Germination

Nucleic acid synthesis in the G₁ cell population of the 1-millimeter apex of the Allium cepa embryo was studied during the initial 73 hours of germination. Quantitative data indicate that the total amount of RNA per cell began to increase after 18 hours of germination while the initial DNA per cell increase did not occur until some 20 hours later. Polyacrylamide gel electrophoresis patterns of ³H-uridine-labeled total nucleic acid samples indicated that synthesis of all detectable RNA fractions present in the pre-emergent 1-millimeter apex (i.e., cytoplasmic and “chloroplast-like” RNA) began at approximately the same time (18 hours). Synthesis of the various cytoplasmic RNA fractions continued throughout the germination period. Data indicating synthesis of the “chloroplast-like” RNA were obtained only for the initial 36 hours of germination. Specific radioactivity of ³H-uridine-labeled total nucleic acid increased during the first 41.5 hours of germination but then decreased while the accumulation of RNA per cell continued to increase throughout the 73-hour period. In addition, a method is described which reduced the bacterial contamination of Allium seed to a level not detectable by incorporation of radioactive precursors into bacterial ribosomal RNA.     

低温对茶树叶片膜脂脂肪酸和蛋白质的影响

本文研究低温胁迫过程中龙井43和大叶云峰叶片膜脂脂肪酸的变化。结果发现,低温下不同品种茶树叶片膜脂脂肪酸配比变化趋势不同,较抗寒的龙井43,不饱和脂肪酸指数(IUFA)和亚麻酸(183)比例随低温期间不同阶段呈现出"低-高-低"的变化趋势;而不抗寒的大叶云峰的变化趋势无明显规律性。此外,还研究了越冬过程中龙井43叶片可溶性蛋白和膜蛋白的变化,发现低温期间龙井43叶片可溶性蛋白含量和组分基本稳定,而膜蛋白含量在低温胁迫时大幅度上升,且经低温诱导出现了46KD、38KD两种新的蛋白组分,并在温度升高后消失。     

邻羟基苯甲酸胁迫对不同杉木无性系叶片膜质过氧化及渗透调节物质的化感效应

研究了杉木自毒物质邻羟基苯甲酸胁迫对2个杉木优良无性系组培苗（分别记为01号、02号）叶片的膜质过氧化及渗透物质的化感效应。结果表明：（1）与对照相比,邻羟基苯甲酸对杉木叶片MDA的化感效应表现为低浓度抑制、高浓度促进,对01号的促进效应低于02号;（2）邻羟基苯甲酸胁迫使杉木叶片电导率及伤害率增加,对照与各胁迫处理间均达显著差异（P〈0．05）,对02号伤害率及电导率的促进效应均大于01号;（3）40mg／L、80mg／L胁迫浓度对2个杉木无性系可溶性糖含量的化感效应随时间变化由抑制转为促进,对01号的促进效应更大、更早,120mg／L胁迫浓度均表现为抑制效应,对01号的抑制效应更小;（4）邻羟基苯甲酸胁迫对杉木叶片游离氨基酸含量均表现为促进效应,且随胁迫浓度升高而增大,对01号的促进效应远远大于02号。研究认为,01号杉木优良无性系具有较强的耐自毒物质胁迫的能力。     

不同时期套袋对幸水梨果实品质、石细胞发育及其相关酶活性变化的影响

以幸水梨为试材分不同时期进行套袋处理,采集各个发育时期的果实,对其果实品质、石细胞团的密度、大小、含量及几种相关酶活性进行了分析.结果表明:(1)不同时期套袋后,幸水梨的硬度、可滴定酸含量均比对照显著增加,可溶性固形物、可溶性总糖含量以及单果重均有不同程度的降低.(2)不同时期套袋果的石细胞含量显著低于对照;与对照果相比套袋果果实表面光洁,果点小而稀,外观品质明显改善.(3)果实石细胞团的密度在幼果期较高,随着果实的发育膨大,密度逐渐减小,成熟前1个月左右基本稳定,石细胞团的纵横径随果实发育先逐渐增大而后减小,石细胞含量也表现出先增加后减少的趋势,在花后第49 d达到最大值.(4)果实内苯丙氨酸解氨酶在果实发育初期的活性较高,随着果实发育逐渐降低;多酚氧化酶活性变化与苯丙氨酸解氨酶相似;过氧化物酶活性随果实的生长呈现先上升后下降的趋势,其活性峰值在盛花后第28 d,其后缓慢下降.(5)不同时期套袋处理后,苯丙氨酸解氨酶、过氧化物酶以及多酚氧化酶活性整体上均比对照降低,与石细胞含量呈正相关关系.