保鲜剂对香石竹切花的保鲜效应

研究了保鲜剂(4％蔗糖 200 mg／L8-HQ 50 mg／L6-BA及4％蔗糖 0．1％明矾 0．02％尿素 0．02％NaCl)对香石竹切花的保鲜效应。结果表明,保鲜剂4％蔗糖 200 mg／L8-HQ 50 mg／L6-BA能明显地缓解切花水分胁迫,改善体内水分平衡,延缓切花衰老,延长切花的寿命。     

Effects of natural ventilation on leaf ultrastructure of Dianthus caryophyllus L. cultured in vitro

Summary Vessel closure configurations exert direct and indirect control over factors pertaining to the physical boundaries of the mieroenvironment, and induce a typical phenotype in in vitro plant production. Upon modification of the in vitro environment, carnation explants showed a gradation of their ultrastructural characteristics from hyperhydric to normal. A higher degree of development was observed in plants from vessels with higher ventilation compared to ones from vessels with low ventilation rates. The cell walls of epidermal cells from both normal and hyperhydric plants grown in nonventilated vessels were less developed than those from plants grown in ventilated vessels. Cytoplasm of normal plants was dense and generally located in parietal areas. The cytoplasm was even more dense in plants grown in ventilated vessels and acclimated. The degree of thylakoid stacking and distribution were affected by ventilation conditions, being poorly developed with low ventilation. Ultrastructurally, stomata from in vitro plants are ready to carry out their task, although there are significant differences in guard cell size and vacuolar area between acclimated and in vitro plants.     

Two Steps of Gas Exchange in Leaf Photosynthesis

Photosynthesis and transpiration of excised leaves of Taraxacum officinale L. and a few other species of plants were measured, using an open gas analysis system. The rates of CO₂ uptake and transpiration increased in two steps upon illumination of stomata-bearing epidermis of these leaves at a light intensity of 50 mW × cm⁻². Abscisic acid inhibited only the second step of gas exchange. Illumination of the astomatous epidermis of hypostomatous leaves caused only the first step of gas exchange. These data indicate that the first and second steps arise from cuticular and stomatal gas exchange, respectively. The rate of the cuticular photosynthesis in a Taraxacum leaf reached saturation at a light intensity of 5 mW × cm⁻², and the rates of the stomatal photosynthesis and transpiration reached saturation at a higher intensity of 35 mW × cm⁻². The cuticular photosynthesis of a Taraxacum leaf was 18% of the stomatal photosynthesis at 50 mW × cm⁻² and 270% at 5 mW × cm⁻². The other species of leaves showed the same trend. The importance of cuticular CO₂ uptake in leaf photosynthesis, especially under low light intensity was stressed from these data.     

Glucose Respiration in Zygorhyncus moelleri; the Entry of Glucose into the Cells

When glucose was added to carbohydrate-starved cells of Zygorhyncus,moelleri the rate of oxygen uptake did not immediately riseto a constant value, but there was a lag period of 2 or 3 hoursbefore it reached its maximum level. The length of this lagperiod increased from a few minutes for short periods of starvationto 2–3 hours after 12 hours in a carbohydrate-free medium.Factors believed to affect cellular permeability (a cationicdetergent, adjustments of the pH, and of the potassium/calciumratio) reduced the length of the lag period by not more than40 per cent. of the original value without affecting the finalrate of oxygen uptake. Investigation of the entry of glucoseinto the cells showed that the rate of oxygen uptake was notlimited by the concentration of intra-cellular glucose for morethat about 11 per cent. of the lag period in starved cells.The reasons for this difference in the percentage of the lagperiod apparently due to a permeability barrier are tentativelydiscussed in connexion with the route by which glucose entersthe cells.     

西花蓟马在康乃馨不同品种上的田间分布

调查西花蓟马Frankliniella occidentalis(Pergande)在10个康乃馨(Dianthus caryophyllus)品种上的发生与分布,比较花朵颜色与气味对西花蓟马寄主选择性的影响。结果表明,花朵上的西花蓟马数量在不同品种间存在显著差异。花朵颜色是影响西花蓟马寄主选择的主要原因,而花朵气味也能影响西花蓟马对寄主的选择性。     

The effect of ventilation rate on proliferation and hyperhydricity of Dianthus caryophyllus L

Summary Comparative studies of carnation micropropagation under four different ventilation rates showed that using gas-permeable filters, with gelled or liquid media and modifying the volume of culture medium, it was possible to establish a suitable hydric state to obtain good proliferation rates with gelled and liquid medium, as well as optimal acclimatization of microcuttings. The following parameters were measured: ventilation rate, gas exchange coefficients, relative water loss, increase of agar concentration, micropropagation rates, percentage of hyperhydricity, and acclimatization rates. Our results confirm that it is possible to avoid hyperhydric plants cultured in liquid medium with the use of ventilated culture vessels through the control of the water relations during the multiplication phase and, at the same time, keeping the micropropagation rate.     

6-苄基腺嘌呤和激动素对香石竹切花衰老的生理效应

6-苄基腺嘌呤（6-BA）和激动素（KT）均能改善香石竹切花体内的水分平衡,增加切花的鲜重,增大花径,提高过氧化物酶（POD）活性,延缓可溶性蛋白质含量下降以及丙二醛（MDA）含量和O2^-·于生成速率的增加,延长切花瓶插寿命2～3d。     

Effect of drought and prolonged refrigeration on senescence in cut carnation (Dianthus caryophyllus)

Severe water stress (40 and 50 h without water at 23°C) and long periods of refrigeration (4 and 5 weeks at 0°C) caused the peak of ethylene production by cut carnation flowers to appear soon after the return to normal conditions. Water stress caused a decrease in ψosm, but this increased back to the initial value on return to normal conditions. Accelerated wilting and massive ion leakage, probably a result of the Joss of membrane integrity, was associated with this premature burst of ethylene. Large amounts of acetaldehyde and ethanol accumulated during prolonged refrigeration (3, 4 or 5 weeks at 0°C). This accumulation of toxic metabolites may explain why the refrigeration of cut flowers for long periods causes a rapid wilting on return to normal conditions.     

Photoautotrophic Growth and Photosynthesis in Cell Suspension Cultures of Chenopodium rubrum

A method is described for growing cell suspension cultures of Chenopodium rubrum photoautotrophically for prolonged periods of time. By using a two-tier culture vessel the growth medium with the cells was separated from the CO₂ reservoir. Definite CO₂ concentrations were established by a K₂CO₃/KHCO₃ buffer. Photoautotrophic growth in C. rubrum cell suspension cultures was correlated with the CO₂ level. At 0.5% CO₂ the cell cultures contained 68 μg chlorophyll/g fresh weight and showed an increase in fresh weight of about 80% in 18 days. At 1% CO₂ an increase in fresh weight of 165% in 18 days was observed. The chlorophyll content rose up to 84 μg/g fresh weight. The photoautotrophic growth was also greatly influenced by the 2,4-D content of the medium. Cell growth was enhanced by lowering the auxin concentration. Best growth was attained (210% increase in fresh weight) at 10^?8M 2,4-D. The photosynthetic activity of the cells was measured by the light dependent ¹⁴CO₂ incorporation. At 0.5% CO₂ the cell suspensions assimilated about 100 μmol CO₂/mg chlorophyll × h. In the presence of 1% CO₂ the light driven assimilation was raised up to 185 μmol CO₂/mg chlorophyll × h. In both cases, the dark incorporation of CO₂ was merely 1.8% of the values obtained in light.     

Regulation of Senescence in Carnation (Dianthus caryophyllus) by Ethylene: Mode of Action

Carnation (Dianthus caryophyllus) flowers were exposed to 2 μl/l ethylene and examined at intervals to determine the time course of wilting, decrease in water uptake, and increase in ionic leakage in response to ethylene. A rapid decrease in water uptake was observed about 4 hours after initiating treatment with ethylene. This was followed by wilting (in-rolling of petals) about 2 hours later. Carbon dioxide inhibited the decline in water uptake and wilting and this is typical of most ethylene-induced responses. Ethylene did not affect closure of stomates. Ethylene enhanced ionic leakage, as measured by efflux of ³⁶Cl from the vacuole. This was judged to coincide with the decrease in water uptake. Gassing flowers with propylene initiated autocatalytic ethylene production within 2.4 hours. Since the increase in ethylene production by carnations preceded the increase in ionic leakage and the decline in water uptake by several hours, it is apparent that the change in ionic leakage does not lead to the initial increase in ethylene production as reported (Hanson and Kende 1975 Plant Physiol 55:663-669) in morning glory but may explain the autocatalytic phase of ethylene production.     

Observations on the Growth of Carnation (Dianthus caryophyllus L.) in Natural and Long Days

Observations were made on the growth and development of carnationsgrown in containers under natural or 24 h days. The number ofleaf pairs produced before flower initiation and the final lengthof each flowering stem were affected by the date at which theshoot appeared and its position on the plant. Dusk-to-dawn lighting reduced the number of axillary shootsin each generation but increased their rate of development.This resulted in similar numbers of flowers being produced inboth treatments. Dianthus caryophyllus L., Carnation, growth, flowering, day length     

Gas Exchange of Algae: II. Effects of Oxygen, Helium, and Argon on the Photosynthesis of Chlorella pyrenoidosa

Changes in the oxygen partial pressure of air over the range of 8 to 258 mm of Hg did not adversely affect the photosynthetic capacity of Chlorella pyrenoidosa. Gas exchange and growth measurements remained constant for 3-week periods and were similar to air controls (oxygen pressure of 160 mm of Hg). Oxygen partial pressures of 532 and 745 mm of Hg had an adverse effect on algal metabolism. Carbon dioxide consumption was 24% lower in the gas mixture containing oxygen at a pressure 532 mm of Hg than in the air control, and the growth rate was slightly reduced. Oxygen at a partial pressure of 745 mm of Hg decreased the photosynthetic rate 39% and the growth rate 37% over the corresponding rates in air. The lowered metabolic rates remained constant during 14 days of measurements, and the effect was reversible after this time. Substitution of helium or argon for the nitrogen in air had no effect on oxygen production, carbon dioxide consumption, or growth rate for 3-week periods. All measurements were made at a total pressure of 760 mm of Hg, and all gas mixtures were enriched with 2% carbon dioxide. Thus, the physiological functioning and reliability of a photosynthetic gas exchanger should not be adversely affected by: (i) oxygen partial pressures ranging from 8 to 258 mm of Hg; (ii) the use of pure oxygen at reduced total pressure (155 to 258 mm of Hg) unless pressure per se affects photosynthesis, or (iii) the inclusion of helium or argon in the gas environment (up to a partial pressure of 595 mm of Hg).     

Gas Chromatographic-Mass Spectrometric Determination of myo-Inositol in Human Cerebrospinal Fluid

The concentration of free myo-inositol in CSF was determined with a gas chromatographic-mass spectrometric method using deuterated myo-inositol as an internal standard after conversion to the hexa-O-acetyl derivative with acetic anhydride and pyridine. Twenty microliters of CSF is sufficient for the analysis which has a coefficient of variation of 9%. Identical analytical results were obtained on two different mass numbers. Schizophrenic patients were compared with healthy control persons. In addition, patients with rheumatoid arthritis or with neurological illnesses were studied. No consistent differences related to the illness could be found. The mean concentration of myo-inositol was about 25 micrograms/ml. Treatment of schizophrenic patients with chlorpromazine or sulpiride had no significant effect on the concentration of myo-inositol in CSF.     

葡萄糖浓度对转基因聚球藻表达hTNF-a和光合作用的影响

为了开发海洋药物,把人肿瘤坏死因子-a(hTNF-a)转入海洋单细胞蓝藻聚球藻7002.然而,转基因聚球藻的hTNF-a表达率很低,仅为可溶性蛋白的0.08%,这不利于进一步纯化.不同浓度的葡萄糖对转TNF-a聚球藻的生长、hTNF-a的表达和光合作用的影响.当葡萄糖浓度为125mmol/L,hTNF-a的表达率达到最高,是不合葡萄糖的6.57.此外,当葡萄糖浓度为75mmol/L时,藻细胞的净光合作用速率达到最大,是光自养藻细胞的1.69倍.在各种葡萄糖浓度下,藻细胞对葡萄糖的吸收都不明显.     

香石竹毛状根诱导、离体培养及其植株再生

为了探讨利用发根农杆菌遗传转化所产生的毛状根来创新香石竹种质的可能性,本文采用叶盘法,建立了发根农杆菌Agrobacterium rhizogenes对香石竹Dianthus caryophyllus L.叶片外植体的遗传转化及其植株再生体系。结果表明,发根农杆菌ATCC15834感染香石竹幼嫩叶片外植体12 d后,从叶片外植体切口中脉处产生白色毛状根,21 d后约90%的叶片外植体产生毛状根。所获得的无菌毛状根能在无外源激素的MS固体和液体培养基中快速自主生长。PCR扩增和硅胶薄层层析结果显示发根农杆菌Ri质粒的rol B和rol C基因以及冠瘿碱合成酶基因已在香石竹毛状根基因组中整合并得到表达。将毛状根置于MS+6-BA 1.0-3.0 mg/L+NAA 0.1-0.2 mg/L中培养15 d后产生淡黄绿色的疏松愈伤组织。愈伤组织不定芽分化的最适培养基为MS+6-BA 2.0 mg/L+NAA 0.02 mg/L,培养6周后不定芽分化率为100%;平均每个愈伤组织产生30-40个不定芽;将不定芽转至1/2 MS或1/2 MS+0.5 mg/L NAA的培养基中10 d后产生不定根,发育成再生植株。再生植株移植于栽培基质中20 d后,成活率达95%以上。     

Effects of CO(2)-Enrichment and of Aminoacetonitrile on Growth and Photosynthesis of Photoautotrophic Calli of Nicotiana plumbaginifolia

Photoautotrophic calli of Nicotiana plumbaginifolia were grown for 3 weeks under two CO₂ concentrations (500 and 20,000 microliters of CO₂ per liter). Calli cultured at high CO₂ exhibited a two-fold higher rate of growth. At CO₂ test levels, these calli were characterized by a lower net photosynthetic capacity than calli cultured at low CO₂. This diminution due to CO₂ adaptation could be ascribed to a 170% stimulation of dark respiration, a 40% decrease in total ribulose-1,5-bisphosphate carboxylase (Rubisco) activity, and also to a feedback inhibition of photosynthesis: high CO₂ grown calli contained about 5.5-fold more sucrose and three-fold less orthophosphate (Pi) than low CO₂ grown calli. Whether the decrease in Rubisco activity is related to the accumulation of sucrose and to the Pi limitation is discussed. Both calli exhibited a Warburg-effect showing the existence of active photorespiration at low CO₂. In calli grown at low CO₂ with 5 millimolar aminoacetonitrile (AAN), an inhibitor of the glycolate pathway, fresh weight decreased by 25% and chlorophyll content by 40%, dark respiration increased by 50% and net CO₂ uptake decreased by about 60% at 340 microliters of CO₂ per liter and 35% at 10,000 microliters of CO₂ per liter. In these calli, glutamine and glutamate contents were half of control calli. In contrast, AAN did not provoke any noticeable effect in calli grown at high CO₂. In photoautotrophic calli, the inhibition of the glycolate pathway by AAN results in severe perturbations in glutamate metabolism and in chlorophyll biosynthesis.     

Effect of Different Sugars on Photosynthesis and Chlorophyll Fluorescence in Photoautotrophic Tomato Suspension Cell Cultures

The effects of metabolisable sugars sucrose and glucose along with non-metabolisable isomers of sucrose palatinose and turanose were tested. Rate of oxygen evolution (P), electron transport rate (ETR), and photochemical quenching (q_p) showed substantial decrease after 24 and 48 h by glucose and sucrose treatments, whereas there was no effect on all these parameters by the treatment with palatinose and turanose. Also the F_v/F_m ratio remained constant through the time of studies revealing that the maximal photochemical capacity of the cells was unchanged. Non-photochemical quenching (q_N) showed a decrease compared to the control values by all the treatments. Hence P and Chl fluorescence parameter were affected only by those sugars which are used in the metabolic pathways and not by sugar analogues.     

Regulation of Senescence in Carnation (Dianthus caryophyllus): Effect of Abscisic Acid and Carbon Dioxide on Ethylene Production

Abscisic acid hastened senescence of carnation flowers and this was preceded by stimulation of accelerated ethylene production. Carbon dioxide delayed the onset of autocatalytic ethylene production in flowers regardless of treatment with abscisic acid. Flowers exhibited a low and transient climacteric of ethylene production without wilting while in 4% carbon dioxide and underwent accelerated ethylene production culminating in wilting when removed from carbon dioxide. Hypobaric ventilation, which lowers ethylene to hyponormal levels within tissues, extended flower longevity and largely negated enhancement of senescence by abscisic acid. Supplementing hypobarically ventilated flowers with ethylene hastened senescence irrespective of abscisic acid treatment. Collectively, the data indicate that abscisic acid hastens senescence of carnations largely as a result of advancing the onset of autocatalytic ethylene production.