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1.
苹果果实糖积累特性与品质形成的关系 总被引:3,自引:1,他引:2
以'富士'和'国光'苹果为研究对象,对其果实发育过程中糖含量及其代谢关键酶活性的变化进行测定分析,以揭示糖分积累代谢特性对果实品质形成的影响.结果表明:(1)'富士'和'国光'均为己糖积累型果实, '富士'果实以积累果糖最多,果糖/葡萄糖(F/G)值为1.56,而'国光'以积累葡萄糖最多,F/G值仅为0.68;蔗糖在两品种中含量和所占比例均很低,在近成熟期'富士'高于'国光'.(2)'富士'果实蔗糖磷酸合成酶(SPS)和蔗糖合成酶(SS)活性均随果实糖的累积量增加而显著升高,酸性转化酶(AI)活性也渐趋升高,而中性转化酶(NI)活性波动不大,且其糖累积与AI和SPS活性相关性最大,而与NI相关性不大,SS的作用主要表现在发育后期;在 '国光'果实糖积累过程中SPS起主导作用,SS和NI的作用主要表现在发育前期,而AI的作用不大.(3)'富士'和'国光'果实淀粉含量变化趋势相同,在淀粉积累高峰之后,'富士'果实淀粉降解速度更快,其淀粉含量迅速下降且低于'国光',此时其相应淀粉酶活性也高于'国光'.研究发现,'富士'和'国光'果实糖积累和淀粉代谢均存在显著差异,从而直接或间接地影响着果实糖代谢过程,进而导致果实品质的显著差异. 相似文献
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One-year-old apple cuttings (Malus pumila var.domestica cv. M26) were grown for 6 months in pot culture with and without inoculum of the VA-mycorrhizal fungus (VAMF)Glomus macrocarpum in soil from a long-term fertilizer field experiment with different P availability (20, 210, and 280 mg CAL-extractable P
kg−1). The indigenous VAMF propagule density was reduced by 0.5 Mrad X-irradiation. At harvest, non-inoculated and inoculated
plants had similar proportions of root length bearing vesicles. Net dry weight of tree cuttings was significantly increased
by inoculation only at 20 mg P kg−1 (+62%). Increasing P availability from 210 to 280 mg P kg−1 led to a 4-week depression of shoot elongation rate only in the inoculated plants. Uptake of P was significantly enhanced
by inoculation at 20 and 210 mg P kg−1 (+64 and +12%, respectively). On average, inoculated plants had significantly higher concentrations of Zn in leaves and in
roots (+16 and +14%, respectively) and of copper in stems and in roots (+13 and +126%, respectively). Proportion of vesicle
bearing root length was significantly correlated with root caloric content. A lipid content of 0.9–4.5% in the root dry matter
was attributed to the presence of vesicles corresponding to 1.6–8.2% of total root caloric content.
As the control plants were also infected, the beneficial effect of VA-mycorrhiza on nutrient uptake and growth of apple cuttings
was underestimated at all P levels. Furthermore, VAM-potential at the lowest P level was not fully exploited as onset of infection
was most certainly delayed because of a decreased photosynthetic rate due to P deficiency. Energy drain by VAMF-infection
was most probably underestimated considerably, due to, among others, loss of infected root cortex during root growth, sampling
and staining.
It is concluded that apple cuttings rely on VA-mycorrhizal P-uptake at least in low P soils. In high P soils, apple cuttings
may profit predominantly from the uptake of Zn and Cu by the fungal symbionts. 相似文献
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The conditioning of apple shoots for several days in an appropriate liquid medium enhances the regenerative capacity of leaf
explants derived from the shoots, so that adventitious buds form in high frequency. The use of conditioning enables the transformation
and rapid recovery of plants from otherwise recalcitrant cultivars without the need for an extended callus phase. Conditioning
has a wide range of effects on the leaf cells, including increasing the density of the cytoplasm and the complexity of vacuoles,
and increasing the porosity of the cell walls from of the order of 3.5 nm to 5.5 nm. The increased porosity may aid the insertion
of T-DNA through the cell wall. Initial expression of introduced genes, as judged by the histochemical assay of the β-glucuronidase
gene, occurs within 2 days of inoculation with Agrobacterium, usually in groups of 2–20 cells, termed foci. The foci are most
commonly composed of an intensely expressing core cell with one or more surrounding layers of less intensely expressing cells.
Explants from conditioned leaves contain at least three times as many foci as the control explants. It is concluded that conditioning
of apple shoots promotes the recovery of transformed plants from leaf explants by two processes: increasing the number of
cells containing and expressing the introduced genes, and by increasing the probability that cells will regenerate directly
to shoots.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Takayuki Hata Kazuki Mukae Soichrou Satoh Mitsuhiro Matsuo Junichi Obokata 《Plant Biotechnology》2021,38(1):179
The Arabidopsis T87 cell line has been widely used in both basic and biotechnological plant sciences. Agrobacterium-mediated transformation of this cell line was reported to be highly efficient when precultured in Gamborg’s B5 medium for a few days. However, because we could not obtain the expected efficiency in our laboratory, we further examined the preculture conditions of Arabidopsis T87 cells in the Agrobacterium-mediated transformation. As a result, we found that preculture in an excess amount of Murashige and Skoog (MS) macronutrients before cultivation in the B5 medium enhanced the transformation efficiency up to 100-fold, based on the transformed callus number on selective gellan gum plates. In this study, transformants were labeled with green fluorescent protein (GFP), and we found multiple fluorescent spots on individual transgenic calli. Therefore, the actual number of transgenic clones seems much more than that of transgenic calli. In our MS macronutrient-rich culture condition, T87 cells tended to aggregate and formed bigger cell clumps, a change that might be related to the enhancement of transformation efficiency. Based on these results, we report an improved protocol of Agrobacterium-mediated transformation of Arabidopsis T87 cells with high efficiency. 相似文献
6.
根癌农杆菌介导的芦荟遗传转化条件的研究 总被引:2,自引:1,他引:1
以美国库拉索芦荟(Aloe.arborescens)的横切薄层切片(transverse thin cell layer, tTCL)作为转化受体, 通过受体材料对抗生素的敏感性实验和Gus 基因瞬时表达率的研究, 找出了较适合的外植体转化条件。研究表明:芦荟对头雹霉素(cefotaxime) 和羧苄霉素(carbenicillin)不敏感, 而对卡那霉素(kanamycin)和潮霉素(hygromycin)敏感;用靠近顶芽的材料得到的横切薄层切片芽再生率高, 有较高的Gus 基因瞬时表达率;乙酰丁香酮(acetosyringone)在芦荟转化是不可缺少的, 对其转化有明显的促进作用。 相似文献
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Apple (Malus pumila var. domestica) phenology is advancing due to rising air temperature in northern Japan 总被引:1,自引:0,他引:1
Recent studies show advancing onset of plant growing season in many regions for the last several decades. With the well‐established dependence of plant phenology on temperature, these trends are interpreted as an indication of global warming. For several decades, however, other determinants of plant phenology, e.g. varieties and trends in managed systems, may have changed and confounded the phenological trends. In this study, we tested if long‐term changes in phenology of apple (Malus pumila var. domestica) are attributable to long‐term changes in temperature by comparing the phenological response to long‐term trend in air temperature, which is of our interest, with that to year‐to‐year fluctuation in air temperature, which should represent the real effect of temperature on phenology. We collected records of air temperature and phenological events (budding and flowering) in apple from 1977 to 2004 at six locations in Japan. Linear trends in flowering showed advancing rate in the range from 0.21 to 0.35 day yr?1, statistically significant at three locations (P<0.05). We also found a warming trend in mean air temperature throughout March and April, with which flowering was closely correlated, in the range from 0.047 to 0.077 °C yr?1, statistically significant at five locations (P<0.05). We separated the temperature time‐series into two components: a long‐term trend and a year‐to‐year fluctuation, by fitting smoothing spline to the trend and taking the residuals as the anomaly. We then fit a multiple regression model of phenological response to air temperature with separate coefficients for long‐term trend and anomaly. Flowering date responded to the long‐term trend at ?3.8 day °C?1 and to the anomaly at ?4.6 day °C?1. The temperature coefficients were not statistically different from each other or among locations, suggesting that the advance of apple phenology has predominantly been caused by the temperature increase across the locations studied. The same result was also observed with budding. 相似文献
8.
BACKGROUND AND AIMS: Demography and spatial distribution of shoots are rarely studied on pruned trees. The present 2-year study deals with the effect of pruning strategies on shoot demography and development, and consequences on the spatial distribution of leaf area in three architecturally contrasted - from type II to IV - apple cultivars: 'Scarletspur Delicious', 'Golden Delicious' and 'Granny Smith'. METHODS: All trees were initially subjected during 5 years to Central Leader training with winter heading on all long shoots. For 2 years, half of the trees were further trained with Centrifugal training, where removal of flowering shoots - called extinction pruning - was carried out along the trunk and at the bottom of branches at flowering time. During these 2 years, shoot type (vegetative, inflorescence) and length, and the three-dimensional spatial distribution of all shoots were assessed with an electromagnetic digitizer. KEY RESULTS: Shoot demography, frequency of transitions toward an inflorescence from either an inflorescence (bourse-over-bourse) or a vegetative shoot (trend toward flowering), and the number of bourse-shoots per bourse were strongly affected by cultivar, with little influence of tree manipulation. In contrast, the proportion of vegetative long shoots developing from previous year latent buds was significantly lower in Centrifugal-trained trees for the three cultivars. Canopy volume showed large variations between cultivars, but only that of 'Granny Smith' was affected by tree manipulation in the 2 years. Spatial distribution of shoots varied significantly according to cultivar and manipulation. In 'Scarletspur Delicious' and, to a lesser extent 'Golden Delicious', the distribution of vegetative and flowering shoots in the outer and the inner parts, respectively, was not affected by tree manipulation. In contrast, in 'Granny Smith', vegetative shoots were stimulated in the periphery of Central Leader trees, whereas flowering shoots were stimulated in the periphery of Centrifugal-trained trees. CONCLUSIONS: In apple, the variability of responses to contrasted pruning strategies partly depends on the genetically determined growth and flowering habit of the cultivar. 相似文献
9.
Fruit ripening involves complex biochemical and physiological changes. Ethylene is an essential hormone for the ripening of
climacteric fruits. In the process of ethylene biosynthesis, cyanide (HCN), an extremely toxic compound, is produced as a
co-product. Thus, most cyanide produced during fruit ripening should be detoxified rapidly by fruit cells. In higher plants,
the key enzyme involved in the detoxification of HCN is β-cyanoalanine synthase (β-CAS). As little is known about the molecular
function of β-CAS genes in climacteric fruits, we identified two homologous genes, MdCAS1 and MdCAS2, encoding Fuji apple β-CAS homologs. The structural features of the predicted polypeptides as well as an in vitro enzyme
activity assay with bacterially expressed recombinant proteins indicated that MdCAS1 and MdCAS2 may indeed function as β-CAS
isozymes in apple fruits. RNA gel-blot studies revealed that both MdCAS1 and MdCAS2 mRNAs were coordinately induced during the ripening process of apple fruits in an expression pattern comparable with that
of ACC oxidase and ethylene production. The MdCAS genes were also activated effectively by exogenous ethylene treatment and mechanical wounding. Thus, it seems like that,
in ripening apple fruits, expression of MdCAS1 and MdCAS2 genes is intimately correlated with a climacteric ethylene production and ACC oxidase activity. In addition, β-CAS enzyme
activity was also enhanced as the fruit ripened, although this increase was not as dramatic as the mRNA induction pattern.
Overall, these results suggest that MdCAS may play a role in cyanide detoxification in ripening apple fruits. 相似文献
10.
The enhancement of tolerance to salt and cold stresses by modifying the redox state and salicylic acid content via the cytosolic malate dehydrogenase gene in transgenic apple plants 下载免费PDF全文
Qing‐Jie Wang Hong Sun Qing‐Long Dong Tian‐Yu Sun Zhong‐Xin Jin Yu‐Jin Hao Yu‐Xin Yao 《Plant biotechnology journal》2016,14(10):1986-1997
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Kumar V Satyanarayana KV Sarala Itty S Indu EP Giridhar P Chandrashekar A Ravishankar GA 《Plant cell reports》2006,25(3):214-222
A system for genetic transformation of Coffea canephora by co-cultivation with Agrobacterium rhizogenes harbouring a binary vector has been developed. The objective of the present study was the genetic transformation and direct
regeneration of transformants through secondary embryos bypassing an intervening hairy root stage. Transformants were obtained
with a transformation efficiency up to 3% depending on the medium adjuvant used. A. rhizogenes strain A4 harbouring plasmid pCAMBIA 1301 with an intron uidA reporter and hygromycin phosphotransferase (hptII) marker gene was used for sonication-assisted transformation of Coffea canephora. The use of hygromycin in the secondary embryo induction medium allowed the selection of transgenic secondary embryos having
Ri T-DNA along with the T-DNA from the pCAMBIA 1301 binary vector. In addition transgenic secondary embryos devoid of Ri-T-DNA
but with stable integration of the T-DNA from the binary vector were obtained. The putative transformants were positive for
the expression of the uidA gene. PCR and Southern blot analysis confirmed the independent, transgenic nature of the analysed plants and indicated single
and multiple locus integrations. The study clearly demonstrates that A. rhizogenes can be used for delivering transgenes into tree species like Coffea using binary vectors with Agrobacterium tumefaciens T-DNA borders. 相似文献
13.
MALDI‐TOF characterization of hGH1 produced by hairy root cultures of Brassica oleracea var. italica grown in an airlift with mesh bioreactor 下载免费PDF全文
Edgar García López Emma Gloria Ramos Ramírez Octavio Gómez Gúzman Graciano Calva Calva Armando Ariza‐Castolo Josefina Pérez‐Vargas Herminia Guadalupe Martínez Rodríguez 《Biotechnology progress》2014,30(1):161-171
Expression systems based on plant cells, tissue, and organ cultures have been investigated as an alternative for production of human therapeutic proteins in bioreactors. In this work, hairy root cultures of Brassica oleracea var. italica (broccoli) were established in an airlift with mesh bioreactor to produce isoform 1 of the human growth hormone (hGH1) as a model therapeutic protein. The hGH1 cDNA was cloned into the pCAMBIA1105.1 binary vector to induce hairy roots in hypocotyls of broccoli plantlets via Agrobacterium rhizogenes. Most of the infected plantlets (90%) developed hairy roots when inoculated before the appearance of true leaves, and keeping the emerging roots attached to hypocotyl explants during transfer to solid Schenk and Hildebrandt medium. The incorporation of the cDNA into the hairy root genome was confirmed by PCR amplification from genomic DNA. The expression and structure of the transgenic hGH1 was assessed by ELISA, western blot, and MALDITOF‐MS analysis of the purified protein extracted from the biomass of hairy roots cultivated in bioreactor for 24 days. Production of hGH1 was 5.1 ± 0.42 µg/g dry weight (DW) for flask cultures, and 7.8 ± 0.3 µg/g DW for bioreactor, with productivity of 0.68 ± 0.05 and 1.5 ± 0.06 µg/g DW*days, respectively, indicating that the production of hGH1 was not affected by the growth rate, but might be affected by the culture system. These results demonstrate that hairy root cultures of broccoli have potential as an alternative expression system for production of hGH1, and might also be useful for production of other therapeutic proteins. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:161–171, 2014 相似文献
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The objectives of this research were first to isolate plastid gene sequences from cabbage (Brassica oleracea L. var. capitata L.), and to establish the chloroplast transformation technology of Brassica. A universal transformation vector (pASCC201) for Brassica chloroplast was constructed with trnV–rrn16S (left) and trnI–trnA–rrn23S (right) of the IRA region as a recombination site for the transformed gene. In transforming plasmid pASCC201, a chimeric aadA gene was cloned between the rrn16S and rrn23S plastid gene borders. Expression of aadA confers resistance to spectinomycin and streptomycin antibiotics. The uidA gene was also inserted into the pASCC201 and transferred into the leaf cells of cabbage via particle gun mediated transformation.
Regenerated plantlets were selected by 200 mg/l spectinomycin and streptomycin. After antibiotic selection, the regeneration
percentage of the two cabbage cultivars was about 2.7–3.3%. The results of PCR testing and Southern blot analysis confirmed
that the uidA and aadA genes were present in the chloroplast genome via homologously recombined. Northern blot hybridizations, immunoblotting and
GUS histochemical assays indicated that the uidA gene were stable integrated into the chloroplast genome. Foreign protein was accumulated at 3.2–5.2% of the total soluble
protein in transgenic mature leaves. These results suggest that the expression of a variety of foreign genes in the chloroplast
genome will be a powerful tool for use in future studies. 相似文献