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71.
在蛹虫草资源调查中,发现两种子实体形态迥异的蛹虫草菌株T和G。栽培试验表明,T菌株子实体矮化膨大,G菌株子实体为棒状.两者子实体长度、直径和产量差异显著。有效成分测定结果表明,菌株T和G子实体中粗多糖的含量分别为1.75%,1.77%,虫草酸为2.81%,2.57%,超氧化物歧化酶(SOD)酶活分别为30.43U/mgprotein、53.49U/mgprotein,过氧化物酶(POD)分别为31.26U/mgprotein,33.49U/mgprotein,过氧化氢酶(CAT)分别为126.35U/mgprotein、137.46U/mgprotein。其中,虫草酸含量、SOD酶活两者差异均显著。 相似文献
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Egbert W. Henry Jeffrey W. Miller Lauren J. Dungy Michael T. Johnson Julia K. Yeekpeh 《Journal of plant nutrition》2013,36(4):353-373
It is usually assumed that plant tissue responses to nutritional elements are due to specific genetic differences that may exist either between inbred or closely related species. Little Marvel (dwarf) and Alaska (normal) varieties of 14‐day old pea seedlings were treated with four different concentrations of Al‐containing nutrient solution (0.0mM, 0.2mM, 0.6mM and distilled H2O), prior to being exposed for 14 days to either DARK, LIGHT, or UV. Selected tissues (root tip, main root, main stem and proximal stem) were bioassayed for peroxidase and polyphenol oxidase enzyme activities, fresh wt vs. dry wt, water uptake and stem growth. The present study suggests that Little Marvel and Alaska pea tissue responds to high toxicity levels of Al by demonstrating an enhancement of enzymic activity. Tissue weight, growth and water uptake also show differential tissue specificity in both Little Marvel and Alaska tissue, in terms of Al toxicity response, given a particular external exposure. 相似文献
75.
V. Nenova M. Merakchiyska G. Ganeva E. Zozikova & S. Landjeva 《Journal of Agronomy and Crop Science》2009,195(3):197-203
Two wheat lines (TL3 and TL5) derived from selection for Cu tolerance among wheat – Aegilops sharonensis hybrids were compared when grown as hydroponics at zero (control), 10−6 and 10−5 m CuSO4 . The morphometric measurements showed that the line TL5 with a more inhibited root system under 10−6 m CuSO4 had a less inhibited shoot growth under 10−5 m CuSO4 as compared to TL3. The decreased maximum efficiency of photosystem II and the more pronounced trend towards increased catalase activity suggested that despite the better shoot growth, the leaves of TL5 were more functionally injured. The increased content of carotenoids at excess Cu and the higher peroxidase and catalase activities of TL3 in control plants might contribute to its better stress tolerance. While no significant changes in enzyme activities were found at 10−6 m Cu, at 10−5 m the activities tended to increase. Although the close values of free phenolics concentrations in control plants, at Cu excess their content was higher in TL5 compared to TL3. The free phenolics content in roots at 10−6 m Cu decreased, and although higher at 10−5 m Cu, it remained below the control in TL3, and above the control in TL5. From the obtained results TL3 emerged to be more tolerant to excess Cu than TL5. 相似文献
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Summary Shoot tip cultures from banana clones susceptible and resistant to Fusarium oxysporum f. sp. cubense (FOC) race 1 and race 4 were grown in vitro in the presence of different concentrations of fusaric acid and fungal crude filtrates or inoculated with a conidial suspension of FOC to assess correlation between in vivo and in vitro behaviour. Explants were susceptible to both filtrate and fusaric acid irrespective to their known field resistance/susceptibility response. No clear linkage between in vivo and in vitro behaviour was observed and our results suggest that the use of crude filtrate or non-host specific toxin (fusaric acid) in a screening programme for selecting a novel resistant genotype of Musa to FOC is not feasible. When peroxidase activity was used as a parameter to discriminate between sesceptibility and tolerance, results were in good agreement with field response of host plant to pathogens. Early enzymatic activity increased in the incompatible host-pathogen interaction but not in the compatible interaction.Abbreviations IBA
Indolebutyric acid
- 2iP
6-dimethylallylamino-purine
- VCG
Vegetative Compatibility Group
- FOC
Fusarium oxysporum f. sp. cubense
- IEF
isoelectrofocusing 相似文献
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Summary We have succeeded in producing useful interspecific hybrid using ovule-embryo culture between Gypsophila paniculata L. Red Sea and G. manginii, an incompatible combination by ordinary cross breeding methods. The hybrid plant had double flowers with a color of pale purplish pink. Hybrid characteristics of the plant were firmed by observation of plant form, flower type, chromosome number and peroxidase isozyme patterns. 相似文献
80.
转枯草芽孢杆菌纤溶酶基因对烟草氧自由基和保护酶系统的影响 总被引:1,自引:0,他引:1
除个别时期外,转枯草芽孢杆菌纤溶酶(Bacillus subtilis fibrinolytic enzyme,BSFE)基因及其信号肽和前肽序列烟草叶、茎、根氧自由基含量、超氧化物歧化酶活性均显著高于野生型烟草植株,抗坏血酸过氧化物酶活性也较野生型烟草植株高,但二者差异不显著。推测氧自由基含量的变化与BSFE的蛋白水解活性有关;超氧化物歧化酶和抗坏血酸过氧化物酶活性变化可能与该转基因烟草植株对外源BSFE基因表达和产物累积产生的逆境适应有关。 相似文献