黄秋葵不同品系和不同组织部位的果胶和咖啡因含量比较研究

黄秋葵是一种具有保健功效的经济作物。通过对10个黄秋葵品系及QK-6不同组织的果胶和咖啡因含量进行了测定,实验结果表明,黄秋葵品系间(取幼嫩果荚为参比)及同种不同部位间的果胶含量差异较大,其中QK-4的果胶含量最高,为24.05%;QK-6中幼嫩果荚的果胶含量明显高于其它部位,达到20.73%。此外,所有黄秋葵中均检测不到咖啡因。上述研究结果为黄秋葵的药用、食用和经济价值的深度开发提供了科学依据。     

糜子不同生育时期不同叶位叶片超微结构研究

对糜子不同生育时期、不同叶位叶片进行电镜观察.结果显示:(1)在籽粒灌浆中期以前,叶肉细胞排列整齐,细胞间隙小,细胞中叶绿体、线粒体等细胞器含量多.叶绿体、线粒体基质含量浓厚,高基粒片层数增加,胞问连丝畅通;(2)在籽粒灌浆中期以后,叶片迅速衰老,细胞解体,细胞间出现间隙,叶绿体减少,叶绿体基粒片层、基质片层解体.嗜锇颗粒变大增多.胞间连丝受到阻碍.(3)不同生育时期不同叶位叶绿体的高基粒片层数差异较大,其中在灌浆中期各叶位叶绿体高基粒片层数最高,在各生育时期旗叶的为最大.     

豆腐柴果胶的纯化及其理化性质研究

豆腐柴为一种民间用作制作传统观音豆腐的小型灌木。通过对所采集的鲜豆腐柴叶经pH值3．5的稀酸性溶液保温,70℃杀菌15min,使叶中果胶酶等酶失活后,于60℃烘干至恒重;干叶用料液比为1：20的盐酸进行酸解,滤液用2．5倍体积的食用酒精进行沉淀、纯化果胶。结果显示每千克干叶可得到纯化果胶0．27kg,果胶得率为27％,酯化度为53％,符合国家对果胶规定的标准,表明该提取方法可行。     

豆腐柴叶果胶的提取工艺条件研究

本文采用正交试验的方法研究了酸解法从豆腐柴叶中提取果胶的最佳提取工艺条件：萃取温度90-95℃、溶液pH值1．5、萃取时间50-60min、料液比1：20,在此条件下豆腐柴叶果胶的提取率为14％-17％。     

不同叶位整形模式对白肋烟生长及烟叶多酚物质含量的影响

叶位整形是一项促进烟叶生长和品质提高的栽培管理措施,为明确不同叶位整形模式对白肋烟生长及多酚物质含量的影响,我们在白肋烟主产区—湖北省恩施州研究了不同叶位整形模式下不同生育期白肋烟的叶面积、叶绿素含量(CCI值)、各器官生物量和上下位叶片中多酚物质含量。结果表明:叶位整形显著影响了白肋烟生长和烟叶多酚物质含量,不但增大了不同叶位烟叶的叶面积及CCI值,还协调了各器官生物量、营养物质的合理分配以及不同叶位烟叶中多酚物质的含量;但不同叶位整形模式对白肋烟的生长影响不同,即旺长期整形(WZ)处理对白肋烟整株的促进作用较好,而团棵后期整形(TH)处理仅对上位叶效果较好。本研究采用的叶位整形栽培管理技术在保证白肋烟产量的同时,可在一定程度上促进白肋烟生长及烟叶品质的提高。     

烟草植株各部位的草酸含量变化（简报）

土培与水培的中烟90烟草植株中草酸含量呈现叶片与根中高,茎中低的哑铃状,根中含量高于叶片,根、,不同叶位叶片和不同部位茎中含量在在早晚没有明显差异。叶片中的含量随叶位不同而不同,成熟叶的含量高于幼叶和老叶。     

豆腐柴叶提取低酯果胶的研究

豆腐柴叶含有丰富的果胶。文中结合盐酸浸提法的基础上,采用醇氨降酯法提取豆腐柴叶的果胶并检测,提取率为部颁19.5%,pH值为2.9,水分和灰分分别为5.13%和8.67%,半乳糖含量为65%,酯化度为38.5%,所提取的低酯果胶的基本性质与国标检测标准接近。果胶成品经AB-8树脂柱纯化后,所提果胶的成分经硅胶板薄层层析初步测定,果胶多糖成分为葡萄糖,果糖,D-甘露糖3种,果胶的溶解度与温度呈正相关性,pH值对其溶解度影响不大。     

珍稀濒危植物珙桐过氧化物酶活性和丙二醛含量

采用比色法测定了不同年龄级、部位和叶位珙桐叶的过氧化物酶(POD)活性和丙二醛（MDA）含量,以探讨珙桐的生理生态适应性。结果表明：不同年龄级同一生长时期珙桐叶的POD活性和MDA含量不同,同年龄级同层的POD活性随叶位增大先升后降,MDA含量随叶位增大逐渐升高;同叶位不同层及同层不同叶位的珙桐叶的POD活性和MDA含量不同。珙桐叶POD活性和MDA含量对生长期敏感,同年龄级同叶位的珙桐叶随叶片的生长、衰老,POD活性和MDA含量逐渐升高,即珙桐叶POD活性和MDA含量受生物和非生物因子影响显著,且不同年龄级、叶位、层次存在差异。     

蕤核叶片化学成分的研究

通过对蕤核叶片化学成分进行定性检测,测出其含有蛋白质、氨基酸、多肽类、生物碱、糖类、黄酮类、有机酸、蒽醌类、酚类和鞣质、挥发油和皂甙这些物质。对不同叶位生物碱和黄酮类物质分布规律进行研究,发现随着叶位降低,两类物质含量呈现先增加后减小的规律,高含量部位分布于第三、四叶位。同时,随着叶位降低,不同叶位叶面积逐渐增加,变化差异显著。     

玉米不同叶位叶片叶绿体超微结构与光合性能的研究

对玉米植株基部（第3叶）,中部（果穗叶）和上部（倒2叶）叶位叶片,进行叶绿体超微结构的观察,并测定了叶绿素含量和光合强度,结果表明,不同叶位叶片叶肉细胞中叶绿体的超微结构,随叶位上升而渐趋复杂化,果穗叶最为显著,向上又趋简单,具体表现为基粒片层的数目随叶位上升而增多基质片层和基质也随之增加,果穗叶最多,向上又趋减少,不同叶位叶片叶绿素含量和光合强度,果穗叶高于其它叶位。     

Diversity of a Complex Centromeric Satellite and Molecular Characterization of Dispersed Sequence Families in Sugar Beet (Beta vulgaris)

BACKGROUND AND AIMS: The hypothesis was tested that pectin content and methylation degree participate in regulation of cell wall mechanical properties and in this way may affect tissue growth and freezing resistance over the course of plant cold acclimation and de-acclimation. METHODS: Experiments were carried on the leaves of two double-haploid lines of winter oil-seed rape (Brassica napus subsp. oleifera), differing in winter survival and resistance to blackleg fungus (Leptosphaeria maculans). KEY RESULTS: Plant acclimation in the cold (2 degrees C) brought about retardation of leaf expansion, concomitant with development of freezing resistance. These effects were associated with the increases in leaf tensile stiffness, cell wall and pectin contents, pectin methylesterase (EC 3.1.1.11) activity and the low-methylated pectin content, independently of the genotype studied. However, the cold-induced modifications in the cell wall properties were more pronounced in the leaves of the more pathogen-resistant genotype. De-acclimation promoted leaf expansion and reversed most of the cold-induced effects, with the exception of pectin methylesterase activity. CONCLUSIONS: The results show that the temperature-dependent modifications in pectin content and their methyl esterification degree correlate with changes in tensile strength of a leaf tissue, and in this way affect leaf expansion ability and its resistance to freezing and to fungus pathogens.     

NaCl-and Gibberellic Acid-induced Changes in the Content of Auxin and the Activities of Cellulase and Pectin Lyase During Leaf Growth in Rice (Oryza sativa)

The interactive effect of NaCl salinity and gibberellic acidin the activities of cellulase and pectin lyase, and on thecontent of auxin and chlorophyll, has been determined duringleaf growth (fifth from base) in rice. The linear growth, chlorophyllcontent, activity of cellulase, and the auxin level of leaveswere markedly decreased when plants were exposed to salt stress(12 dS m^–1). However pectin lyase activity did not registerany significant alteration in the leaves of salt-stressed plantscompared with the control. Treatment of plants with gibberellicacid (GA₃) (10 ppm) increased the leaf growth and chlorophyllcontent with a concomitant rise in the activity of cellulaseunder stressed as well as non-stressed conditions. A markedincrease in the content of auxin was discernible in the leavesof salt-stressed plants treated with GA₃ compared with non-treatedsalinized ones. An appreciable increment in the activity ofpectin lyase in response to GA₃ administration was detectedonly in the leaves of non-stressed plants. These results indicatethat enhancement of cellulase activity and the augmentationof endogenous auxin content may be involved in the stimulationof rice leaf growth by GA₃ under saline conditions. Oryza sativa, rice, leaf growth, NaCl salinity, gibberellic acid, cellulase, pectin lyase, auxin     

Concentration and retention of chlorophyll around the extrafloral nectary of Mallotus japonicus

Plants need to allocate some of their limited resources for defense against herbivores as well as for growth and reproduction. However, the priority of resource allocation within plants has not been investigated. We hypothesized that plants with extrafloral nectaries (EFNs) invest more chlorophyll around their EFNs—to support a high rate of carbon fixation there—than in other leaf parts of young leaves. Additionally, this chlorophyll may remain around EFNs rather than in the other leaf parts. We used Mallotus japonicus plants to investigate the chlorophyll content at leaf centers and edges and around EFNs at four stages of leaf development: middle‐expanded young leaves, fully expanded mature leaves, senior leaves, and leaves prior to abscission. These four stages of development were located at the third, fifth, eighth, and eleventh leaf positions from the apex, respectively. The results revealed that the chlorophyll content around the EFN side of the third‐position leaves was higher than that at the leaf center or edge. Although the chlorophyll content in the fifth‐position leaves did not differ between those at the leaf edge and around EFNs, the chlorophyll content around EFNs in the eighth‐position leaves was higher than that at the leaf centre and edge. The volume of EF nectar was positively correlated with the chlorophyll content around EFN during the leaf stage, but it was not correlated with the chlorophyll content in the leaf center and edge, except in fifth‐position leaves. These findings suggest that M. japonicus plants facilitate and maintain secretion of EF nectar in their young and old leaves, respectively, through the concentration and retention of chlorophyll around EFNs.     

Several changes of Indocalamus leaf active ingredients contents

In this paper, the leaves of Indocalamus herklotsii, Indocalamus decorus, and Indocalamus latifolius were collected from Nanjing in different seasons to study the seasonal changes of the total flavonoids, tea polyphenols, and soluble sugar contents in the leaves. There existed significant differences in the test active ingredients contents among the leaves of the three Indocalamus species. The leaf total flavonoids content of the three Indocalamus species in different seasons ranged in 1.7%-2.7%, being the highest for I. herklotsii and I. decorus in spring and for I. latifolius in winter. The leaf tea polyphenols content varied from 5.5% to 7.6%; and the leaf soluble sugar content was 1.0%-8.5%, with the maximum in spring. Within the three months after leaf unfolding, the active ingredients contents in I. herklotsii and I. decorus leaves increased with leaf age. The optimal period for harvesting Indocalamus leaves was from December to next March. Among the three Indocalamus species, I. latifolius had the highest contents of the three active ingredients in leaves, suggesting that I. latifolius had greater potential value in the utilization of its leaf active ingredients than the other two species.     

Differences in water relations and physiological characteristics in leaves of wheat associated with leaf position on the plant

The seasonal change in leaf water potential and its components, stomatal resistance, specific leaf weight, photosynthesis rate, the activities of ribulose-1,5-bisphosphate carboxylase and nitrate reductase, and soluble proteins were measured in flag leaves (ninth from base in position), seventh and fifth leaves of wheat Triticum aestivum L. cv Kalyansona. Flag leaves had a lower water and solute potential and lower or equal turgor pressure than seventh and fifth leaves. These differences were found to be independent of environment. The rate of photosynthesis and nitrate reductase activity were always lower in fifth and seventh leaves than in flag leaf. The photosynthetic efficiency in flag leaves appeared to be associated with lower stomatal resistance and higher specific leaf weight. The relations between leaf water potential and relative water content showed a change with leaf position. This change possibly allows flag leaf to maintain its functional efficiency despite its lower water potential.     

3种功能型林木幼苗叶片与细根碳氮磷化学计量特征及其异速关系

为了比较不同功能型林木叶片与细根碳氮磷化学计量特征及其异速关系的差异,本研究以刨花楠(常绿阔叶)、福建山樱花(落叶阔叶)和福建柏(常绿针叶)的幼苗为对象,对其叶片和细根的碳(C)、氮(N)、磷(P)含量及其计量比关系进行分析。结果表明: 3种树木幼苗的叶片与细根的C、N、P含量及其计量比存在显著差异,其中,叶片与细根的C含量及C/N、C/P均以刨花楠最高,N含量和N/P以福建山樱花最高,P含量以福建柏最高;3种幼苗叶片的C、N、P含量和C/P、N/P均高于细根。叶片的C、N、P含量及其计量比之间的异速关系与细根不同,且受功能型差异的影响;3种幼苗叶片的C/P与N/P之间存在着指数明显不同的异速关系,但其细根的N、P含量均为等速关系。3种幼苗叶片和细根的C、N、P含量及其计量比关系也存在差异;刨花楠叶片和细根的关系主要显示为叶片C含量与细根P含量的异速关系,福建山樱花则主要显示在叶片C、N含量及C/N、N/P与细根C/N、N/P间的异速或等速关系,而福建柏主要是叶片C含量与细根C、N、P含量间的异速关系,福建山樱花叶片与细根的养分分配更具协调性。3种幼苗叶片和细根对P的投资策略具有相似性。研究结果为实施林木苗期精准养分管理与高效培育技术等提供了科学依据。     

补骨脂中呋喃香豆素类物质的积累规律及组织定位

应用高效液相色谱技术,分析了补骨脂(Psoralea corylifolia)不同器官、不同发育时期补骨脂素和异补骨脂素的含量变化规律。2种呋喃香豆素类物质在补骨脂的根、茎、叶、花、果实和种子中均有积累,其含量在果实中最高,根中最低,幼嫩茎叶高于成熟茎叶,成熟期果实高于幼嫩期果实。通过组织化学和荧光显微技术对呋喃香豆素类物质的定位研究,同时结合分泌腔的系数与2种呋喃香豆素的含量相关性分析,证明补骨脂中分泌腔是2种呋喃香豆素积累的主要场所。     

银杏叶片形态研究

通过对银杏不同枝类、不同叶序的叶片形态进行调查,结果表明:银杏不同枝类的叶片形态差异较大,叶宽、叶柄长、叶基角:多年生鳞枝＞一年生鳞枝＞一年生长枝;叶长、叶形指数:一年生长枝＞一年生鳞枝＞多年生鳞枝;叶面积:一年生和多年生鳞枝＞一年生长枝;有缺刻叶比例:一年生长枝＞多年生鳞枝＞一年生鳞枝.一年生长枝叶片的叶宽、叶长、叶面积、叶柄长、叶基角均随叶序的增加逐渐减小,叶形指数和有缺刻叶的比例则增加.一年生和多年生鳞枝1～5叶的叶长、叶宽和叶面积随叶序增加而逐渐增加,第5～6叶达最大,以后随叶序增加而逐渐减小,叶形指数和叶柄长度随叶序增加而增加,叶基角随叶序增加而减小.一年生长枝的第2叶、一年和多年生鳞枝的第4叶可作为品种描述的标准叶.     

Relationships between the severity of leaf blotch (Rhynchosporium secalis) and the water-soluble carbohydrate and nitrogen contents of barley plants

Water-soluble carbohydrate (WSC) and total nitrogen (N) contents of leaves of field-grown barley plants were measured in 1966 and 1967. Consistent differences were found between cultivars. The susceptibility of cultivars to leaf blotch was correlated negatively with WSC content and positively with N content at G.S. 10.4. Application of nitrogen fertiliser (which increased N and decreased WSC) also increased the severity of leaf blotch. The occurrence of primary lesions on seedlings does not seem to be affected by their WSC and N contents and the relation between WSC and N contents of leaves and severity of leaf blotch possibly depends on differences in growth and sporulation of the pathogen on substrates containing different amounts of carbohydrate and nitrogen.     

大穗型小麦叶片性状、养分含量及氮素分配特征

采用田间试验研究了8个大穗型小麦新品系和西农979不同生育期比叶面积(SLA)、叶干物质含量(LDMC)与养分含量的差异性,并对其不同器官氮素积累和分配情况进行了探讨。结果表明,大穗型小麦的SLA和LDMC平均值小于西农979;小麦叶片养分含量由大到小依次为全氮(N)、全钾(K)和全磷(P);成熟期大穗型小麦品系各器官平均氮素积累能力都高于对照,氮素积累量及分配比例的大小顺序为籽粒>茎+鞘>穗草(穗轴+颖壳)>旗叶>倒二叶>余叶;大穗型小麦平均转移率和贡献率较西农979低;抽穗期旗叶SLA和LDMC呈负相关关系,SLA和N含量呈不显著的正相关,和P、K呈极显著的负相关。小麦叶片结构性状与养分含量影响体内有机物质的积累与转运,通过水肥调控措施来提高大穗型小麦养分利用效率的研究需进一步加强。