巴山榧树营养器官的解剖学研究

以2年生巴山榧树幼苗为试材,采用常规石蜡切片方法和光学显微技术,研究了巴山榧树根、茎、叶的解剖结构,以期为巴山榧树的深入研究与保护利用提供参考依据。结果表明:2年生巴山榧树幼苗根的结构由周皮、次生维管组织和初生木质部组成;根内无髓部和树脂道;次生韧皮部中无石细胞。茎的结构由周皮、皮层、次生维管组织、初生木质部和髓组成;木质部中无树脂道,有少量木薄壁组织细胞;木射线单列。叶片结构由上下表皮、叶肉组织和叶脉组成;表皮细胞壁显著增厚,具角质层;气孔仅分布于下表皮,下表皮气孔带区域具有分叉的角质钉;叶肉组织分化为栅栏组织和海绵组织,叶肉中具有分枝状石细胞;维管束1条,在维管束的远轴面内生树脂道1个,泌脂细胞2~3层。     

水芹适应湿地环境的解剖和屏障结构组织化学特征研究

利用普通光学显微镜和荧光显微镜对水芹的根、茎进行解剖结构和屏障结构研究。结果表明:水芹不定根为初生结构,具二、三原型维管柱、内皮层、皮层、皮下层和表皮;茎亦为初生结构,具髓腔、皮层(皮层内有通气组织、散生维管束、厚角组织)和表皮。水芹体内气腔包括不定根的通气组织、茎内髓腔和皮层的通气组织。水芹的屏障结构包括不定根内侧具凯氏带且栓质化的内皮层,外侧不同发育时期的表皮栓质层、木质化皮下层和气腔周围细胞壁栓质层;茎的角质层和木质化厚角组织。水芹的体内气腔和质外体屏障结构是其适应湿地环境并改善湿地通气的重要结构保证。     

黑马河草原4种植物茎的解剖结构研究

利用常规石蜡切片的方法对黑马河草原上的4种植物茎的解剖结构观察比较,结果表明：这4种植物茎的基本结构具有相似性,均由表皮、皮层、维管柱3部分组成;它们的共同显著特征都具有较发达的髓部及皮层厚角组织;茎中维管组织与基本组织（皮层和髓）的比值较低。综合植物茎的解剖结构说明,这4种植物都具有适应寒、旱生环境的典型结构特征。     

宝石花营养器官解剖结构

应用石蜡切片技术,在光学显微镜下观察研究宝石花根、茎、叶的解剖结构。研究结果表明,根具有明显髓;茎皮层较厚,皮层和髓部均由大量具发达液泡的薄壁细胞组成;叶肥厚多汁,外被蜡质层;叶肉无栅栏组织和海绵组织的分化,主要由体积大的储水薄壁细胞组成;气孔器为不等型,随机单个散布于叶表皮;茎和叶含有大量薄壁组织细胞或储水组织细胞;所观察的宝石花茎和不定根有一定的次生生长,包括周皮和次生维管组织,次生木质部中导管数量多。研究发现,茎和叶含有大量薄壁组织细胞或储水组织细胞,根和茎具有一定次生生长,叶肥厚、外被蜡质层,以及气孔器随机单个散布,可能与宝石花较强的抗旱性有关;此外,根、茎和叶中富有的异细胞及异细胞中被番红染为红褐色的条状物质,可能与抗旱性也有关系。     

葡萄茎插条不定根起源的组织学观察

<正> 关于不定根在茎中起源部位的研究,大约在1758年由法国的树木学家 Duhamel duMonceau 首先开始的。其后许多学者对一些草本与木本植物进行了大量的研究,并已证明不定根的发生部位依植物种类不同而异。不定根可以由表皮,皮层薄壁组织,次生韧皮部,未成熟的多列射线,形成层和髓部发生。而关于葡萄茎插条内不定     

豆瓣绿营养器官解剖结构

采用石蜡切片法,在光学显微镜下观察豆瓣绿(Peperomia tetraphylla)根、茎、叶的解剖结构。结果表明:根具周皮,初生木质部脊数为4,有较多晶体;茎肉质,无次生结构,维管束散生于基本组织中,表皮外侧有单细胞毛,基本组织中存在油细胞类异细胞;叶较肥厚,上表皮具角质层而无气孔器,下表皮分布有不等型气孔器但无明显角质层,叶肉由近轴面贮水组织层和远轴面同化组织层组成。根具周皮、晶体,茎肉质具大量薄壁细胞,叶具角质层和贮水组织层等特征可能与其抗旱性有关。     

掌叶覆盆子营养器官解剖结构及其特征分析

以江西德兴掌叶覆盆子为试材,采用光学显微镜及石蜡切片、徒手制片技术,研究掌叶覆盆子不同发育时期的根、茎、叶营养器官的解剖结构特征,探讨其结构特征与环境适应性关系。结果表明:根的次生结构中次生木质部和木栓层发达,有利于增加根系运输矿质养分和水分的能力,保护其内部组织免受高温灼烧,增强抗旱性。根的次生结构中产生大量木薄壁细胞、木射线和韧皮射线、韧皮部薄壁细胞,成为营养物质贮存的场所,为根上不定芽的发生、发育提供充足养分奠定了基础,与其每年萌发新枝、2年生枝结果然后死亡的生长特性相适应;茎的次生结构中导管分子口径大,数量多,茎中央髓部大,具有明显旱生形态特征;叶为典型异面叶;上表皮细胞整齐,排列紧密,气孔少见;下表皮气孔器密度较大;栅栏组织和海绵组织发达,表现出阳生叶的结构。     

紫花玉簪根的解剖学研究

应用常规石蜡切片技术和番红—固绿滴染色的方法,观察玉簪根的成熟区形态解剖学。玉簪根的解剖结构观察表明:玉簪根的初生结构是由表皮、皮层和中柱三部分构成,其中中柱包括中柱鞘、初生的木质部、初生的韧皮部和髓四部分。     

不同品种紫斑牡丹茎结构与抗寒性关系研究

在前期引种驯化栽培与适应性观察、生理生化、叶片解剖结构的研究基础上,以"紫冠玉珠""青春""紫楼闪金""雪里藏金""玉瓣绣球""实生苗"6个品种紫斑牡丹为试材,比较分析了不同品种间茎的表皮、角质层、表皮细胞外壁、厚角组织、皮层、木质部、韧皮部、导管直径、髓半径、茎半径的差异,探究紫斑牡丹茎结构与抗寒性的关系。结果表明:不同品种紫斑牡丹茎厚角组织、角质层、皮层厚度与抗寒性无关联;表皮细胞外壁厚度、导管直径和茎半径与抗寒性无明显关联;表皮细胞厚度、木质部厚度、韧皮部厚度及髓半径与抗寒性呈正相关联,可作为引种栽培的参考指标。     

绿玉树营养器官解剖结构研究

应用石蜡切片技术,在光学显微镜下观察绿玉树根、茎、叶等营养器官的解剖结构,以探讨其营养器官结构上的抗旱性特征。结果表明:绿玉树根和茎具有次生生长,产生周皮和次生维管组织。根皮层,茎皮层和髓以及叶肉中具有体积较大的储水细胞。根、茎、叶含有被染为红褐色或深灰色物质的异细胞,茎、叶的部分细胞中存在簇晶。根次生木质部中管孔较大,轴向木薄壁细胞较多。茎表面具密集小乳突,薄壁组织细胞中存在较多淀粉粒。叶片肉质较厚,等面叶,气孔器平列型,表面有较厚角质层。绿玉树根的导管较粗和木薄壁组织发达,根、茎和叶中具有较多储水细胞等特征与抗旱性有关。     

Physiological and physico-chemical changes in green papaya (Carica papaya L. ‘Kaek Noul’) shreds taken from the outer or inner mesocarp

This study compared physiological and physico-chemical changes in shreds of green papaya (Carica papaya L. ‘Kaek Noul’), taken from inner and outer mesocarp tissues, during storage at 7ºC for up to 8 d. Reductions in the flesh firmness of shreds, microstructure, colouration, dry matter content (DMC), and fresh weight (FW) loss, and in the rates of respiration, ethylene production, and enzyme activities were measured. The rapid loss of firmness of green papaya ‘Kaek Noul’ shreds taken from the inner mesocarp was attributed to the larger and more loosely arranged cells of the inner mesocarp compared to the smaller and compact cells of the outer mesocarp. Shreds taken from the outer mesocarp had a higher DMC [6.21–6.77% (w/w)] than those from the inner mesocarp [5.83–6.34% (w/w)] during storage at 7ºC. FW loss was higher for shreds from the inner mesocarp than from the outer mesocarp (0.89–1.12% vs. 0.39–1.00%, respectively). Colour values (h°) were lower at the end of storage for shreds from the inner mesocarp than shreds from the outer mesocarp (104.38° and 111.94°, respectively). Moreover, scanning electron micrographs of shreds from inner mesocarp and outer mesocarp tissues showed that the slower loss of firmness in shreds from the outer mesocarp could be attributed to having smaller and more compact cells, as well as to lower ethylene production by the outer mesocarp. However, this was not related to cellulase activity. This study indicated why processors prefer to use shreds from the outer mesocarp of green papaya.     

The Development of Adventitious Roots on Hardwood Cuttings of Gooseberries

Changes in percentage dry weight and in carbohydrate levels and distribution were followed in Golden Brown Lockyer onion bulbs for three months at storage temperatures of 4°, 15°, 25° and 37°C. The percentage dry weight within the bulbs increased from the outer to the inner leaf bases. Storage temperature and length of storage did not influence water loss. Sucrose concentrations increased from the outer leaf bases to become highest in the inner leaf bases, and in all leaf bases were higher at higher temperatures. Glucose and fructose levels also tended to increase from outer to inner leaf bases. After eight weeks fructose levels increased rapidly at the lower storage temperatures and this is attributed to low-temperature hydrolysis of fructans. The only fructan detected was the trisaccharide fraction, which was barely detectable in outer leaf bases and maximal in the inner ones. Trisaccharide levels were generally lower at the lower temperatures, thus supporting the suggestion of low-temperature hydrolysis of fructans. No information was obtained regarding storage temperature effects on fructans having a higher degree of polymerization than the trisaccharide. The results are discussed relative to temperature and time and the development of storage rots.     

离体条件下苹果摘袋日烧发生过程中果皮细胞超微结构的变化

 对套双层纸袋的富士苹果采收后摘袋,探讨全除袋与先摘外袋3 d后摘除内袋对果实日烧发生的影响。结果表明,套袋果实一次性除袋后,当日即呈现日烧症状,表皮细胞结构破坏,叶绿体解体;先摘外袋3 d后摘除内袋,果实无日烧发生,且着色,着色部位部分叶绿体向有色体转化;不摘袋处理的果实表现正常,细胞结构完整。结果说明果实长期套袋后,摘袋时先除外袋而保留数日内袋,可防止因突然性强光对果皮细胞膜的伤害而导致日烧发生。     

球色对大白菜VC和可溶性固形物分布的影响

以不同球色的大白菜为试材,测定收获期大白菜的内、外叶的叶柄、软叶的VC及可溶性固形物含量。结果表明:桔红心白菜和深绿色、淡黄心的直筒类型大白菜VC含量、可溶性固形物含量高于绿色、白心大白菜;VC含量分布总趋势是内叶高于外叶、软叶高于叶柄;可溶性固形物含量分布总趋势是内叶高于外叶。     

低钾胁迫对生菜光合作用以及内、外叶片钾含量与可溶性糖含量的影响

摘要：为探明缺钾生菜外形正常而生长缓慢的原因，研究了不同程度钾缺乏对生菜的影响。以“巴达维亚”生菜为材料，通过营养液量的管理方法，设置4个梯度的钾供给量，分别为常规用量对照组以及1/2、1/4、1/8钾供给量，分析钾缺乏处理下生菜叶片的钾含量和可溶性糖含量以及光合作用的变化。结果表明：1/2和1/4处理中生菜的净光合速率、气孔导度、胞间二氧化碳浓度和蒸腾速率与CK相比均无显著差异，1/8处理则均较CK显著降低。1/2、1/4、1/8处理下生菜内、外叶片钾含量均逐渐降低，可溶性糖含量均逐渐上升；随着叶片钾含量的降低，外、内叶钾含量比值和外、内叶可溶性糖含量比值均有所上升，这表明生菜在遭受钾缺乏时，将更多功能性物质分配于外叶以维持其正常功能，而内叶由于分配较少导致生长缓慢。     

Tipburn of Chinese cabbage in relation to calcium nutrition and distribution

Heading Chinese cabbage (Brassica campestris ssp. pekinensis Rupr.) grown with low Ca or B developed dark tan lesions near the leaf margins. A synergistic effect of low Ca and low B accompanied the development of this symptom. Plants grown under humid conditions were free of tipburn. Plants grown under less humidity developed tipburn. Total chemical analysis revealed a steady decrease in total Ca from the outer to the inner leaves. Fractional chemical analysis showed 7 times more water-soluble Ca in the outer than in the inner leaves, and 2 times more 1 N NaCl-soluble Ca in the outer than in inner leaves. Threshold concentration of water-soluble forms of Ca for tipburn was around 3.0 mg/g dry weight. Data suggest that root pressure flow is required to move adequate amounts of water-soluble Ca to the wrapper leaves to prevent tipburn of Chinese cabbage.     

Seasonal changes in cellular compartmentation and membrane permeability to sugars in relation to early or high temperature-induced watercore in ‘Orin’ apples

Summary

The intensity of watercore in ‘Orin’ apples (Malus domestica Borkh.) from the outer canopy increased from early-July to mid-August, followed by a decrease through late-October, while no watercore was detected in inner canopy fruit during the same period. Seasonal changes in sorbitol content in each cellular compartment paralleled the development of watercore. Significantly higher sorbitol, fructose and glucose contents in the vacuoles of cells in outer canopy fruit than in inner canopy fruit suggest that active metabolism and uptake of sorbitol might occur in watercored apples in mid-August. The permeability of sorbitol across the tonoplast was significantly higher in outer than in inner canopy fruit after mid-August, whereas no difference was observed between bearing position for the other sugars or for the plasma membrane. These data suggest that elevated sorbitol levels in the intercellular spaces might result from active apoplastic unloading and not from an inhibition of metabolism and/or an increase in leakage from cells.     

Physiological and anatomical changes associated with ripening in the inner and outer mesocarp of cold stored ‘Songold’ plums and concomitant development of internal disorders

Plums (Prunus salicina cv. Songold) were cold stored for 10 d at -0.5°C followed by 18 d at 7.2°C and 7 d at 10°C. On the day of harvest and after 15,30 and 35 d of storage, the physiology, anatomy and development of internal disorders in inner and outer mesocarp tissue were assessed. Soluble solids, juice pH, internal conductivity, viscosity of soluble pectin and membrane leakage were significantly higher in the inner tissue, while titratable malic acid levels were lower, indicating that fruit was riper on the inside than the outside. Changes as indicated by the same variates showed that the rate of ripening in inner tissue was more rapid than in the outer mesocarp tissue over storage time. Gel breakdown in inner tissue was associated with high viscosities of water soluble pectin, permeable membranes, and as a result, binding of cell fluids which led to low levels of extractable juice. In outer tissue where extractable juice levels were higher, overripeness developed. At the ultrastructural level, it was evident that cell walls of inner tissue were thicker and had a better developed middle lamella than outer tissue. Inner mesocarp tissue was composed of larger cells than outer tissue.     

The relationship between leaf growth,calcium accumulation and distribution,and tipburn development in field-grown butterhead lettuce

The change in calcium (Ca) concentration with time, the distribution of Ca within various leaves, and leaf and tipburn development were studied in field-grown lettuce (Lactuca sativa L.) cultivar ‘Cobham Green’.Ca distribution between and within leaves followed two distinct patterns. The average concentrations in the outer leaves were always higher than in the inner leaves. The concentrations at the periphery of the outer leaves was always greater than in the midrib, whereas for the inner leaves the converse was true.Tipburn only occurred in the inner leaves; it developed on only those leaves and those parts of the leaf which expanded most rapidly.Thus, tipburn development appears to depend on the supply of Ca relative to the rate of leaf growth.