Characterization of cytoplasmic male sterility in Petunia hybrida and Zea mays. Localization and activity of cytochrome c oxidase     

R. J. Bino  L. C. J. M. Suurs  S. J. de Hoop  A. Van Der Neut  J. L. Van Went  G. A. M. Van Marrewijk 《Euphytica》1986,35(3):905-918

Summary Anthers of male fertile, cytoplasmic male sterile (cms), and restored male fertile Petunia hybrida, are analyzed for cytochrome c oxidase (cox) activity in subsequent stages of microsporogenesis, and compared with anthers of male fertile, cms-S and cms-C Zea mays. The cox activity is determined in anther extracts and cytochemically. In petunia anthers, the first differences in cox activity occur from meiosis onward. However, at these stages, the initial symptoms of degeneration are already apparent. It is suggested that the decline in enzyme activity of the cms petunia anthers is the result rather than the cause of the non-formation of functional pollen.In maize anthers, the cox activity of sterile-type anthers is reduced in comparison with fertile-type anthers from premeiosis onward. There are also consistent cytochemical differences in the mitochondrial organization of cox activity between pollen of cms-S and male ferile maize anthers. In fertile-type mitochondria, the DAB reaction product indicating cox activity is localized in the cristae and within the space between the outer and inner limiting membranes of the organelles. In mitochondria of pollen of cms-S maize, cox activity is only observed between the outer and inner membranes of the mitochondria. The biochemical and cytochemical differences are observed at stages of development at which no structural signs of degeneration are apparent. The results suggest that cms in maize correlates with deviations in cytochrome c oxidase activity.Abbreviations cox cytochrome c oxidase - DAB 3,3-diaminobenzidine  相似文献   

热胁迫对大豆花荚离层细胞HSP70基因表达、能量供应及花荚脱落率的影响   总被引：1，自引：0，他引：1  

柴国华  吕慧颖  李辉亮  陈建南  聂晶  张利明  朱保葛 《农业生物技术学报》2006,14(4):574-577

实验运用Northern blot检测和生理生化分析等技术研究热胁迫对大豆(Glycine max)品种花荚离层细胞的HSP70基因表达、能量供应及花荚脱落的影响。结果显示，热胁迫能够提高所有6个供试大豆品种花荚离层细胞的HSP70基因表达水平、线粒体及其蛋白含量以及细胞色素氧化酶表达量，而不同程度地降低了所有供试品种的花荚脱落率。结果说明，大豆花荚离层细胞HSP70基因的高效表达可能是通过有效地改善花荚离层细胞的能量供应，从而达到抑制花荚脱落的目的。关键词: 大豆；热胁迫；HSP70基因；线粒体；细胞色素氧化酶；花荚脱落率  相似文献   

Contribution of mineral nutrition to the response of barley seedlings to polyethylene glycol–induced mild water stress     

Konstantina V. Kocheva  Georgi I. Georgiev  Reneta V. Vunkova‐Radeva 《植物养料与土壤学杂志》2007,170(3):392-397

The effect of polyethylene glycol–induced osmotic stress on the activity of nitrate reductase, glutamine synthetase, and glycolate oxidase in leaves of young barley plants grown under two nutrient‐supply regimes was studied. The activity of nitrate reductase gradually decreased after polyethylene glycol (PEG) application, while glutamine synthetase and glycolate oxidase were increased. It is speculated that the enhanced glutamine synthetase and glycolate oxidase activities are due to increased flux of metabolites through the photorespiratory cycle. Prominent increase in concentrations of free proline, reducing sugars, and free amino acids was observed. The possible contribution of these cellular solutes to the process of osmotic adjustment and the role of mineral supply is discussed. It is suggested that low N supply in combination with stress conditions switched the preferred osmolyte type from amino acids (N‐containing) to sugars (C‐containing).  相似文献   

Influence of selenium on oxidoreductive enzymes activity in soil and in plants     

Janina Nowak  Krzysztof Kaklewski 《Soil biology & biochemistry》2004,36(10):1553-1558

The aim of this greenhouse experiment was the assessment of the influence of H₂SeO₃ at soil concentrations of 0.05, 0.15 and 0.45 mmol kg⁻¹, on the activity of selected oxidoreductive enzymes in wheat (Triticum aestivum). The wheat plants were grown in 2 dm³ pots filled with dust-silt black soil of pH 7.7. Applied H₂SeO₃ caused activation of plant nitrate reductase at all concentrations, but activation of plant polyphenol oxidase at only two lower concentrations. The highest concentration caused inhibition of polyphenol oxidase and peroxidase. Plant catalase activity decreased under the influence of 0.15 and 0.45 mmol kg⁻¹ concentration. After the final analysis Se was quantified in plants and soil. The amounts in plants were: control (unamended soil) 1.95 mg kg⁻¹; I dose (0.05 mmol kg⁻¹) 18.27 mg kg⁻¹; II dose (0.15 mmol kg⁻¹) 33.20 mg kg⁻¹ and III dose (0.45 mmol kg⁻¹) 38.37 mg kg⁻¹, in soil: 0.265 mg kg⁻¹; 3.61 mg kg⁻¹; 10.53 mg kg⁻¹; 30.53 mg kg⁻¹; respectively. Simultaneously, a laboratory experiment was performed, where the activity of soil catalase and peroxidase were tested after 1, 3, 7, 14, 28, 56, and 112 days after Se treatment. Peroxidase activity in soil decreased with increasing Se content, over the whole experiment. The lowest dose of Se caused activation a significant 10% increase in catalase activity, but the influence of others doses was unclear.  相似文献   

树莓总多酚及其抗氧化功能研究     

王丽  王振宇  樊梓鸾  左丽丽 《中国林副特产》2011,(5):17-20

树莓中含有降低慢性疾病发生的抗氧化活性物质,研究用溶剂法提取悬钩子中生物活性物质,并测定总多酚及提取物的抗氧化活性。丙酮作为溶剂提取的树莓中总多酚,用福林酚法测定其含量为708．54mg／100g鲜果。通过测定树莓提取物清除DPPH自由基、ABTS自由基、羟自由基、超氧阴离子自由基的能力,评价其抗氧化活性。结果表明提取物具有较强的体外抗氧化能力,这可能与树莓中的多酚含量有关。因此,悬钩子具有良好的抗氧化活性,可作为一种潜在的用于抗癌活性物质的来源。  相似文献   

The role of potassium in alleviating detrimental effects of abiotic stresses in plants   总被引：6，自引：0，他引：6  

Ismail Cakmak 《植物养料与土壤学杂志》2005,168(4):521-530

Plants exposed to environmental stress factors, such as drought, chilling, high light intensity, heat, and nutrient limitations, suffer from oxidative damage catalyzed by reactive oxygen species (ROS), e.g., superoxide radical (O₂equation/tex2gif-sup-1.gif^–), hydrogen peroxide (H₂O₂) and hydroxyl radical (OHequation/tex2gif-sup-4.gif). Reactive O₂ species are known to be primarily responsible for impairment of cellular function and growth depression under stress conditions. In plants, ROS are predominantly produced during the photosynthetic electron transport and activation of membrane‐bound NAD(P)H oxidases. Increasing evidence suggests that improvement of potassium (K)‐nutritional status of plants can greatly lower the ROS production by reducing activity of NAD(P)H oxidases and maintaining photosynthetic electron transport. Potassium deficiency causes severe reduction in photosynthetic CO₂ fixation and impairment in partitioning and utilization of photosynthates. Such disturbances result in excess of photosynthetically produced electrons and thus stimulation of ROS production by intensified transfer of electrons to O₂. Recently, it was shown that there is an impressive increase in capacity of bean root cells to oxidize NADPH when exposed to K deficiency. An increase in NADPH oxidation was up to 8‐fold higher in plants with low K supply than in K‐sufficient plants. Accordingly, K deficiency also caused an increase in NADPH‐dependent O₂equation/tex2gif-sup-6.gif^– generation in root cells. The results indicate that increases in ROS production during both photosynthetic electron transport and NADPH‐oxidizing enzyme reactions may be involved in membrane damage and chlorophyll degradation in K‐deficient plants. In good agreement with this suggestion, increases in severity of K deficiency were associated with enhanced activity of enzymes involved in detoxification of H₂O₂ (ascorbate peroxidase) and utilization of H₂O₂ in oxidative processes (guaiacol peroxidase). Moreover, K‐deficient plants are highly light‐sensitive and very rapidly become chlorotic and necrotic when exposed to high light intensity. In view of the fact that ROS production by photosynthetic electron transport and NADPH oxidases is especially high when plants are exposed to environmental stress conditions, it seems reasonable to suggest that the improvement of K‐nutritional status of plants might be of great importance for the survival of crop plants under environmental stress conditions, such as drought, chilling, and high light intensity. Several examples are presented here emphasizing the roles of K in alleviating adverse effects of different abiotic stress factors on crop production.  相似文献   

Molecular mapping of the AOX1a and β‐AmyI genes in potato     

Dominika Krusiewicz  Henryka Jakuczun  Iwona Wasilewicz‐Flis  Danuta Strzelczyk‐Żyta  Waldemar Marczewski 《Plant Breeding》2011,130(4):500-502

  相似文献   

Combined effects of sodium chlorite dip treatment and chitosan coatings on the quality of fresh-cut d’Anjou pears     

Zhenlei XiaoYangchao Luo  Yaguang LuoQin Wang 《Postharvest Biology and Technology》2011,62(3):319-326

This study evaluated the effects of sodium chlorite (SC) alone and its sequential treatment with edible coatings on browning inhibition and quality maintenance of fresh-cut d’Anjou pears. Edible coatings were prepared from chitosan (CH) and its water-soluble derivative carboxymethyl chitosan (CMCH), separately. Pear wedges were immersed in SC solution, followed by coating with CH or CMCH solutions. The samples were packed in unsealed bags and stored at 4 °C for subsequent color, firmness, and weight loss measurement. The effects of the SC and coating treatments on polyphenol oxidase (PPO) inhibition and microbial inactivation were also evaluated. Results indicated that SC exhibited significant (P < 0.05) inhibition of browning and PPO activity. The SC treatment was also strongly effective in inactivating Escherichia coli O157:H7 on pear slices. Coating SC-treated pear slices with CH adversely affected the quality of pear slices by accelerating the discoloration of cut surfaces and increasing the PPO activity. On the contrary, coating SC-treated samples with CMCH significantly prevented the browning reaction and inhibited PPO activity. In addition, SC and CH/CMCH coatings maintained tissue firmness and did not affect weight loss. Our study may provide a scientific basis for the use of SC + CMCH treatment as an alternative preservation treatment for fresh-cut fruits and vegetables.  相似文献   

桑籽皮多酚的提取工艺研究     

田艳花  张虹  党莉  杨小兰 《农产品加工．学刊》2011,(3):52-54

通过单因素试验,分析了不同浸提剂、浸提剂浓度、料液比、浸提时间、浸提温度5个因素对桑籽皮多酚提取量的影响,通过正交试验,确定了桑籽皮多酚的最佳提取条件为:浸提剂(丙酮)体积分数为70%,料液比1∶35,回流温度45℃,回流时间1.5h。在此提取条件下,提取量达到1.332mg/g干籽皮,为桑籽皮多酚的工业化提取提供科学依据。  相似文献   

烘烤过程多酚氧化酶抑制剂对烤烟多酚的影响     

李尼杭  卢红  杨焕文 《云南农业大学学报(自然科学版)》2007,22(1):69-73

 选用4种多酚氧化酶抑制剂处理备烤烟叶,与对照进行烘烤比较试验。通过对烤后烤烟样品总酚、绿原酸、芸香苷含量及烘烤前鲜烟匀浆中多酚氧化酶活性的检测。比较结果显示：常规烘烤条件下4种抑制剂对烤烟多酚含量无明显影响;在不当的烘烤条件下,4种处理样品的多酚含量明显高于对照,其中对烤烟多酚降解抑制作用最强的是NaDiCa,聚乙烯吡咯烷酮相对弱些但无异味,它们可能是防止不当烘烤导致烟叶褐变的有效抑制剂。鲜活烤烟匀浆中4种抑制剂对多酚氧化酶活性抑制作用由强到弱依次为NaDiCa,聚乙烯吡咯烷酮,EDTA和硫脲。匀浆酶活性检测结果与整叶烘烤处理后烤烟样品总酚含量高低顺序不完全一致,可能是不同抑制剂在烟叶组织中渗透性不一致引起,值得进一步研究。  相似文献