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1.
PAM (Pulse Amplitude Modulation) fluorometer techniques directly measure the light reactions of photosynthesis that are otherwise difficult to estimate in CAM (Crassulacean Acid metabolism) plants such as pineapple (Ananas comosus comosus cv. Phuket). PAM machines calculate photosynthesis as the Electron Transport Rate (ETR) through PSII (4 electrons per O2 produced) as mol m?2 s?1. P vs. E curves fitted the waiting-in-line function (an equation of the form $ {\hbox{ETR}} = \left( {{\hbox{ET}}{{\hbox{R}}_{{ \max }}} \times {\hbox{E}}/{{\hbox{E}}_{\rm{opt}}}} \right).{{\hbox{e}}^{{1} - {\rm{E}}/{\rm{Eopt}}}} $ ) allowing half-saturating and optimal irradiances (Eopt) to be estimated. Effective Quantum Yield (Ymax), Electron Transport Rate (ETRmax) and the Non-Photochemical Quenching parameter, NPQmax all vary on a diurnal cycle but the parameter qNmax does not show a systematic variation over a diurnal period. Phuket pineapple is a “sun plant” with Optimum Irradiance (Eopt) from 755 to 1,130 μmol m?2 s?1 (400–700 nm) PAR but photosynthetic capacity is very low in the late afternoon even though light conditions are favourable for rapid photosynthesis. Total CO2 fixed nocturnally as C4-dicarboxylic acids by leaves of the Phuket pineapple was only ≈0.14 gC m?2 d?1 (0.012 mol C m?2 d?1). Titratable acid of leaves was depleted about 3 pm (15:00) and shows a classical CAM diurnal cycle. The Phuket pineapple variety only stored enough CO2 as C4 acids to account for only about 2.5% of photosynthesis (Pg) estimated using the PAM machine (≈5.6 gC m?2 d?1). Phuket pineapples are classifiable as CAM-Cycling plants but nocturnal fixation of CO2 is so low compared to the more familiar Smooth Cayenne variety that it probably recycles only a small proportion of the respiratory CO2 produced in leaves at night and so even CAM-cycling is only of minor importance to the carbon economy of the plant. Unlike the Smooth Cayenne pineapple variety, which fixes large amounts of CO2 nocturnally, the Phuket pineapple is for practical purposes a C3 plant. 相似文献
2.
Characterization of Phosphoenolpyruvate Carboxykinase from Pineapple Leaves Ananas comosus (L.) Merr
Phosphoenolpyruvate carboxykinase has been partially purified from pineapple (Ananas comosus [L.]) leaves. Specific activities obtained show it to be a major activity in this tissue. Above 15 C, the respective activation energies for decarboxylation and carboxylation are 13 and 12 kcal/mol. Below 15 C, there are discontinuities in Arrhenius plots with an associated large increase in activation energy. The adenine nucleotides are preferred to other nucleotides as substrates. The apparent Km values in the carboxylation direction are: ADP 0.13 mm, HCO(3) (-) 3.4 mm, and phosphoenolpyruvate 5 mm. In the decarboxylation direction, the apparent Km values are: ATP 0.02 mm, ADP 0.05 mm, and oxaloacetate 0.4 mm. The decarboxylation activity had an almost equal velocity with either ADP or ATP. The pH optima are between 6.8 and 7. Inhibition of the carboxylation reaction by ATP, pyruvate, and carbonic anhydrase was demonstrated. Decarboxylase specific activities are over twice carboxylation activities. The data support a model in which phosphoenolpyruvate carboxykinase is of physiological significance only during the light period and then only as a decarboxylase. 相似文献
3.
Enzymatic browning and biochemical alterations in black spots of pineapple [Ananas comosus (L.) Merr. 总被引:1,自引:0,他引:1
Penicillium funiculosum Thom. was consistently isolated from pineapple-infected fruitlet (black spots). Polyphenol oxidase, peroxidase, and laccase activities were determined in extracts from contiguous and infected fruitlets. Healthy fruitlets showed a rather high level of polyphenol oxidase (optimum pH 7.0), and this activity was tremendously increased (X 10) in contiguous infected fruitlets. Furthermore, infected fruitlets also exhibited laccase activity (optimum pH 4.0), while peroxidase was rather constant in both fruitlets. Browning reactions were attributed to qualitative and quantitative modifications of the enzymatic equipment (polyphenol oxidase and laccase) (p < 0.0001). In infected fruiltets, sucrose and L-malic acid were present at significantly lower amounts than in healthy ones, likely owing to fungal metabolism (p < 0.0001), whereas cell wall material was three times higher, which could be viewed as a defense mechanism to limit expansion of the mycelium. 相似文献
4.
Tokitomo Y Steinhaus M Büttner A Schieberle P 《Bioscience, biotechnology, and biochemistry》2005,69(7):1323-1330
By application of aroma extract dilution analysis (AEDA) to an aroma distillate prepared from fresh pineapple using solvent-assisted flavor evaporation (SAFE), 29 odor-active compounds were detected in the flavor dilution (FD) factor range of 2 to 4,096. Quantitative measurements performed by stable isotope dilution assays (SIDA) and a calculation of odor activity values (OAVs) of 12 selected odorants revealed the following compounds as key odorants in fresh pineapple flavor: 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDF; sweet, pineapple-like, caramel-like), ethyl 2-methylpropanoate (fruity), ethyl 2-methylbutanoate (fruity) followed by methyl 2-methylbutanoate (fruity, apple-like) and 1-(E,Z)-3,5-undecatriene (fresh, pineapple-like). A mixture of these 12 odorants in concentrations equal to those in the fresh pineapple resulted in an odor profile similar to that of the fresh juice. Furthermore, the results of omission tests using the model mixture showed that HDF and ethyl 2-methylbutanoate are character impact odorants in fresh pineapple. 相似文献
5.
Polysaccharide composition of unlignified cell walls of pineapple [Ananas comosus (L.) Merr.] fruit. 总被引:1,自引:0,他引:1
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The polysaccharides of cell walls isolated from the fleshy, edible part of the fruit of the monocotyledon pineapple [Ananas comosus (L.) Merr.] (family Bromeliaceae) were analyzed chemically. These cell walls were derived mostly from parenchyma cells and were shown histochemically to be unlignified, but they contained ester-linked ferulic acid. The analyses indicated that the noncellulosic polysaccharide composition of the cell walls was intermediate between that of unlignified cell walls of species of the monocotyledon family Poaceae (grasses and cereals) and that of unlignified cell walls of dicotyledons. Glucuronoarabinoxylans were the major non-cellulosic polysaccharides in the pineapple cell walls. Xyloglucans were also present, together with small amounts of pectic polysaccharides and glucomannans (or galactoglucomannans). The large amounts of glucuronoarabinoxylans and small amounts of pectic polysaccharides resemble the noncellulosic polysaccharide composition of the unlignified cell walls of the Poaceae. However, the absence of (1-->3,1-->4)-beta-glucans, the presence of relatively large amounts of xyloglucans, and the possible structure of the xyloglucans resemble the noncellulosic polysaccharide composition of the unlignified cell walls of dicotyledons. 相似文献
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7.
M. Escalona J. C. Lorenzo B. González M. Daquinta J.L. González Y. Desjardins C. G. Borroto 《Plant cell reports》1999,18(9):743-748
A procedure for the mass propagation of pineapple plants (Ananas comosus L. Merr) using a temporary immersion technique is described. This procedure involved three distinct phases in the automated
temporary immersion system: shooting, bud differentiation and elongation. To establish this protocol, we used in vitro shoots
obtained from established liquid culture as starting materials. Three culture methods (solid, liquid and temporary immersion)
were compared. Temporary immersion increased the multiplication rate and fresh and dry weight after 42 days. Conventional
micropropagation (liquid medium) and temporary immersion were compared in combination with paclobutrazol. Paclobutrazol promoted
the formation of compact bud clusters with limited leaf development. The highest multiplication rate (106) was found when
ex-plants were cultured in shooting medium (MS+2.1 mg/l BA+0.3 mg/l NAA) supplemented with 1 mg/l PB for 7 weeks. A 10-l temporary
immersion bioreactor was used to test two approaches during elongation stage: reduction of the shoot-formation period or decrease
of the initial number of explants. The highest number of competent and uniform plants (191.8 plant/l) was achieved when shoots
were cultured for 4 weeks in shooting medium supplemented with PB.
Received: 4 February 1998 / Revision received: 22 June 1998 / Accepted: 14 August 1998 相似文献
8.
菠萝种质目标起始密码子(SCoT)遗传多样性分析 总被引:1,自引:0,他引:1
利用SCo T分子标记技术对来自9个国家或地区的46份菠萝种质进行了遗传多样性分析,并对SCo T标记在菠萝研究中的效率做了探讨。结果表明,SCo T标记在菠萝种质中具有丰富的多态性,引物多态性条带百分比在75%~100%之间,平均为94.61%;引物的有效等位基因数(Ne)、Nei's基因多样性指数(H)、Shannon's信息指数(I)和多态性信息含量(PIC)平均值分别为1.45、0.27、0.41和0.28,表明SCo T标记具有较高的多态性检测效率。基于SCo T标记计算获得的遗传相似系数对菠萝种质做聚类分析,46份菠萝种质可被划分为5个类群,其中,第Ⅰ类群所包含的菠萝种质数量最多,占菠萝种质总数的84.78%。主成分分析获得了与聚类分析不尽一致的结论,但两者反映的种质亲缘关系基本一致。本研究结果将为我国菠萝种质的鉴定、保存和科学利用提供一定的理论依据。 相似文献
9.
Zong-Ping Zheng Jinyu Ma Ka-Wing Cheng Jianfei Chao Qin Zhu Raymond Chuen-Chung Chang Ming Zhao Zhi-Xiu Lin Mingfu Wang 《Phytochemistry》2010,71(17-18):2046-2051
Two sulfur-containing compounds, (S)-2-amino-5-((R)-1-carboxy-2-((E)-3-(4-hydroxy-3-methoxyphenyl)allylthio)ethyl-amino)-5-oxopentanoic acid (1) and (S)-2-amino-5-((R)-1-(carboxymethylamino)-3-((E)-3-(4-hydroxyphenyl)allylthio)-1-oxopropan-2-ylamino)-5-oxopentanoic acid (2), and one 1H-pyrrole-2-carboxylic acid derivative, 6-(3-(1H-pyrrole-2-carbonyloxy)-2-hydroxypropoxy)-3,4,5-trihydroxy-tetrahydro-2H-pyran-2-carboxylic acid (3), together with eighteen known phenolic compounds, were isolated from the fruits of pineapple. Their structures were elucidated by a combination of spectroscopic analyses. Some of these compounds showed inhibitory activities against tyrosinase. The half maximal inhibitory concentration values of compounds 1, 4, 5, 6, 7 are lower than 1 mM. These compounds may contribute to the well-known anti-browning effect of pineapple juice and be potential skin whitening agents in cosmetic applications. 相似文献
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Jaya R. Soneji P. S. Rao Minal Mhatre 《Journal of plant biochemistry and biotechnology.》2002,11(2):117-119
Multiple shoots were regenerated from leaf explants obtained from in vitro grown shoot cultures of pineapple. Each leaf was horizontally cut into three pieces (~ 0.5 cm, basal, middle and tip) and cultured onto MS basal medium supplemented with 2% sucrose and various growth regulators.The explant containing the basal part of the leaf gave rise to tiny protuberances which grew into shoots.The highest number of shoots were obtained on MS basal medium supplemented with 2,4-D (0.90 µM) and 2iP (0.98 pM).These shoots were subcultured ontowhite’s basal medium supplemented with 1% sucrose, NAA (0.54 µM) and IBA (1.97 µM). Plantlets produced in vitro were transferred to paper cups containing autoclaved soil or Soilrite, hardened in the greenhouse and established in soil.The protocol provides an easy propagation system for pineapple, an otherwise vegetatively propagated fruit crop. 相似文献
12.
. Tufts of multiple shoots were produced from dormant, axillary buds of pineapple in vitro. Tiny shoots (2-5 mm) isolated from the tuft of multiple shoots were encapsulated in 3% sodium alginate prepared using hormone-free Murashige and Skoog's basal medium, Murashige and Skoog's vitamins, 0.56 mM myo-inositol and 0.06 M sucrose. The encapsulated shoots represented synthetic seeds that germinated and formed roots in vitro after subculture onto one of the following media solidified with 0.8% agar: (1) hormone-free Murashige and Skoog's basal medium, Murashige and Skoog's vitamins, 0.56 mM myo-inositol and 0.06 M sucrose (Pin1), (2) Murashige and Skoog's basal medium, Murashige and Skoog's vitamins, 0.56 mM myo-inositol, 0.06 M sucrose, 9.67 µM 1-naphthalene acetic acid, 9.84 µM indole-3-butyric acid and 9.29 µM kinetin (Pin2), and (3) White's basal medium, White's vitamins, 0.56 mM myo-inositol, 0.03 M sucrose, 0.54 µM 1-naphthalene acetic acid and 1.97 µM indole-3-butyric acid (Pin3). Pretreatment of shoots in either liquid Pin3 or Pin4 medium (White's basal medium, White's vitamins, 0.56 mM myo-inositol, 0.03 M sucrose, 10.8 µM 1-naphthalene acetic acid and 39.4 µM indole-3-butryic acid) was required for development into plantlets with roots after culture on either Pin1, Pin2 or Pin3 media. One hundred percent germination of synthetic seeds to plantlets occurred after pretreatment of shoots in liquid Pin4 medium for 12 h followed by culture of synthetic seeds on Pin2 medium. Synthetic seeds stored at 4°C remained viable without sprouting for up to 45 days. Plantlets produced in vitro from synthetic seeds were successfully established in soil. The protocol provides an easy and novel propagation system for pineapple, an otherwise vegetatively propagated fruit crop. 相似文献
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Flowering is a crucial developmental stage in the plant life cycle. A number of different factors, from environmental to chemical, can trigger flowering. In pineapple, and other bromeliads, it has been proposed that flowering is triggered by a small burst of ethylene production in the meristem in response to environmental cues. A 1-amino-cyclopropane-1-carboxylate synthase (ACC synthase) gene has been cloned from pineapple (ACACS2), which is induced in the meristem under the same environmental conditions that induce flowering. Two transgenic pineapple lines have been produced containing co-suppression constructs designed to down-regulate the expression of the ACACS2 gene. Northern analysis revealed that the ACACS2 gene was silenced in a number of transgenic plants in both lines. Southern hybridization revealed clear differences in the methylation status of silenced versus non-silenced plants by the inability of a methylation-sensitive enzyme to digest within the ACACS2 DNA extracted from silenced plants, indicating that methylation is the cause of the observed co-suppression of the ACACS2 gene. Flowering characteristics of the transgenic plants were studied under field conditions in South East Queensland, Australia. Flowering dynamics studies revealed significant differences in flowering behaviour, with transgenic plants exhibiting silencing showing a marked delay in flowering when compared with non-silenced transgenic plants and control non-transformed plants. It is argued that the ACACS2 gene is one of the key contributors towards triggering 'natural flowering' in mature pineapples under commercial field conditions. 相似文献
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16.
A random amplified polymorphic DNA (RAPD) analysis of spineless (variant phenotype) plants obtained from micropropagated dormant
pineapple (Ananas comosus L., Merr.) axillary buds was performed using arbitrary 10-mer oligonucleotide primers. This was done to investigate the genetic
fidelity of the regenerants and to distinguish these variants from regenerants bearing the normal spined phenotype. Of the
58 arbitrary primers used, 29 produced bands unique to the spineless phenotype, and 30 produced bands unique to the spined
phenotype. A total of 914 bands were scored, 55 of which were polymorphic to the spineless phenotype and 51 of which were
polymorphic to the spined phenotype. On the basis of RAPD amplification products, genetic similarity was estimated in both
types of regenerants using similarity coefficients (Nei and Li, 1979). The characteristic finger-prints generated by each
probe emphasize genetic variability of regenerants. This technique is suitable for analyzing variant regenerants induced in
vitro. 相似文献
17.
Edwige Sopie Yapo Tanoh Hilaire Kouakou Mongomaké Kone Justin Yatty Kouadio Patrice Kouame Jean-Michel Merillon 《Journal of plant biochemistry and biotechnology.》2011,20(2):196-204
An efficient protocol for a complete plant regeneration by somatic embryogenesis was developed with Smooth Cayenne pineapple (Ananas comosus L.). Previous works showed that this species is responsive to somatic embryogenesis. In the present work the influence of components of culture medium in the induction, development and conversion of somatic embryos was investigate in order to establish a somatic embryogenesis protocol. Nodular callus (83.67%) was initiated from leaf explants of young plants on CIM3 medium. The highest frequency (37.6%) of embryogenic callus induction was obtained from 4-week-old calluses on EIM3 medium supplemented with 3.0 mg/l picloram. The highly organized callus induction and the development of somatic embryos were achieved after the transfer of callus clumps onto EIM3 medium containing 1.0 mg/l BAP + 0.1 mg/l NAA. The frequency of somatic embryo formation was of 39.5?±?2.45 embryos per callus. Up to 97% of the somatic embryos were converted into complete plants within 4 week on MSB medium with 1.0 mg/l BAP + 0.05 mg/l GA3 + 500 mg/l glutamine. The continuation of the elongation of the shoots occurred on this medium). Shoots obtained from all the above methods were rooted in MSB medium with activated charcoal. Complete plantlets were transferred onto specially made polyethylene bags containing soil mixture and transferred to the greenhouse. Survival rate of the plantlets under ex vitro conditions was 98% and maximum average number of plantlets (80?±?0.6). The well-developed plantlets were transferred to an open field where the plants produced normal fruits. 相似文献
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19.
16S Ribosomal DNA Characterization of Nitrogen-Fixing Bacteria Isolated from Banana (Musa spp.) and Pineapple (Ananas comosus (L.) Merril) 总被引:1,自引:0,他引:1
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Leonardo Magalhes Cruz Emanuel Maltempi de Souza Olmar Baler Weber Jos Ivo Baldani Johanna Dbereiner Fbio de Oliveira Pedrosa 《Applied microbiology》2001,67(5):2375-2379
Nitrogen-fixing bacteria isolated from banana (Musa spp.) and pineapple (Ananas comosus (L.) Merril) were characterized by amplified 16S ribosomal DNA restriction analysis and 16S rRNA sequence analysis. Herbaspirillum seropedicae, Herbaspirillum rubrisubalbicans, Burkholderia brasilensis, and Burkholderia tropicalis were identified. Eight other types were placed in close proximity to these genera and other alpha and beta Proteobacteria. 相似文献
20.
Jian-sheng Wang Jun-hu He Hua-rui Chen Ye-yuan Chen Fei Qiao 《Biochemical genetics》2017,55(5-6):347-366
Inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers were used to assess the genetic diversity of 36 pineapple accessions that were introduced from 10 countries/regions. Thirteen ISSR primers amplified 96 bands, of which 91 (93.65%) were polymorphic, whereas 20 SSR primers amplified 73 bands, of which 70 (96.50%) were polymorphic. Nei’s gene diversity (h = 0.28), Shannon’s information index (I = 0.43), and polymorphism information content (PIC = 0.29) generated using the SSR primers were higher than that with ISSR primers (h = 0.23, I = 0.37, PIC = 0.24), thereby suggesting that the SSR system is more efficient than the ISSR system in assessing genetic diversity in various pineapple accessions. Mean genetic similarities were 0.74, 0.61, and 0.69, as determined using ISSR, SSR, and combined ISSR/SSR, respectively. These results suggest that the genetic diversity among pineapple accessions is very high. We clustered the 36 pineapple accessions into three or five groups on the basis of the phylogenetic trees constructed based on the results of ISSR, SSR, and combined ISSR/SSR analyses using the unweighted pair-group with arithmetic averaging (UPGMA) method. The results of principal components analysis (PCA) also supported the UPGMA clustering. These results will be useful not only for the scientific conservation and management of pineapple germplasm but also for the improvement of the current pineapple breeding strategies. 相似文献