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将 3种剂量 (1× 10 17N+ /cm2 ,2× 10 17N+ /cm2 ,3× 10 17N+ /cm2 )的氮离子束注入烟草品种RG 17的干燥种子和 2× 10 17N+ /cm2 的氮离子束注入云烟 85种子中 ,然后播种育苗 ,并进行生理指标的测定。结果表明 :氮离子注入烟草种子后 ,烟苗根系活力增强 ,叶片中的脯氨酸含量明显提高 ,硝酸还原酶活性有所降低 ,超氧化物歧化酶 (SOD)活性增强 ,叶绿素含量提高。氮离子注入对烟草生理特性的影响因剂量和烟草品种的不同而有一定的差异 相似文献
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The Effects of Low-Energy Nitrogen Ion Implantation on Pollen Exine Substructure and Pollen Germination of Cedrus deodara 总被引:1,自引:0,他引:1
The aim of this study is to investigate the biological effects of ion beams on pollen. Pollen grains of Cedrus deodara were implanted with 30 keV nitrogen ion beams at doses ranging from 1 × 10^15 ions/cm^2 to 15 × 10^15 ions/cm^2. The effects of N^+ implantation on the pollen exine substructure were examined using an atomic force microscope (AFM), and the structure and morphology of pollen and pollen tubes were observed using a laser scanning confocal microscope (LSCM). AFM observations distinctly revealed the erosion of the pollen exine caused by N^+ implantation in the micrometer to nanometer range. Typical results showed that the erosion degree was linearly proportional to the ion dose. Pollen germination experiments in vitro indicated that N^+ implantation within a certain dose range increased the rate of pollen germination. The main abnormal phenomena in pollen tubes were also analyzed. Our results suggest that low energy ion implantation with suitable energy and dosage can be used to break the pollen wall to induce a transfer of exogenous DNA into the pollen without any damage to the cytoplasm and nuclei of the pollen. The present study suggests that a combination of the method of ion-beam-induced gene transfer and the pollen-tube pathway method (PTPW) would be a new plant transformation method. 相似文献
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以亚油酸制备的薄膜和水溶液为材料,研究不同剂量、剂量率紫外线对亚油酸的过氧化损伤。分别采用硫代巴比妥酸(Thiobarbituric acid,TBA)法和紫外分光光度法检测受照样品中丙二醛(MDA)和共轭二烯的变化情况。结果表明,剂量率相同时,亚油酸的过氧化程度随紫外照射量增大而增大;总照射量不变时,亚油酸的过氧化程度随着剂量率的增大而减小;膜状态下亚油酸对紫外辐射敏感性比溶液状态下强。 相似文献
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采用亚临界萃取技术处理卷烟烟丝,考察处理后烟丝加工性能、化学成分、挥发性有机物、农药残留、烟气常规指标及感官质量的变化情况。结果表明:亚临界萃取处理后的烟丝耐加工性略微变差,但不影响其可用性;萃取过程无溶剂残留;在对照样中检出的三种农残,二甲醚处理的样品中均未检出,丁烷处理样三种农残的去除率分别为50.0%、43.8% 和70.0%;二甲醚和丁烷处理样制成卷烟后主流烟气中焦油的释放量分别降低了12.7% 和8.5%,水分、CO 和烟气烟碱量也有不同程度降低;感官评吸显示柔细程度、余味、刺激性均好于对照;二甲醚处理样卷烟烟气中除NNK 和巴豆醛的释放量基本不变外,苯酚、HCN、氨、CO 及苯并[a] 芘的释放量分别下降了19.7%、18.8%、33.3%、19.5% 和 25.2%,卷烟危害指数由13.5 降至10.9。说明亚临界萃取技术适用于卷烟的减害降焦。 相似文献
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