1、磁场处理黄瓜种子对其幼苗抗旱性的影响中文随着全球气候变暖和世界人口的不断增加，水资源短缺及其在全球时空分布不均造成包括中国在内的 80 多个国家严重缺水。干旱已经成为世界农业生产的主要限制因素，也是人类面临的最重大难题之一。因此，近年来国内外关于利用各种物理方法提高农作物的抗旱性已成为世界农业生产重要的研究课题。在利用电场、磁场和激光等处理手段提高农作物抗旱性方面取得了广泛的效果。本课题用磁场处理黄瓜种子，研究对其幼苗抗旱性的影响，获得了有益的生物学效益，这对于用物理方法提高农作物抗旱性的研究具有重要意义。实验用磁感应强度为 100mT、200mT、300mT 和 400mT 的磁场分别处理黄
2、瓜种子 1min、5min 和 10min，分别标记为T11、T12、T13、T21、T22 、T23、T31、T32、T33、T41、T42 和 T43。在种子萌发第 9 天后，用不同浓度的聚乙二醇(PEG，分子量 6000)进行模拟干旱胁迫：模拟干旱胁迫第 1 天用 5%PEG 模拟干旱胁迫，第 2 天用 10%PEG 模拟干旱胁迫，每 24h 后 PEG 浓度增加 5%，直到第 5 天， PEG 浓度增加到 25%，模拟自然环境中持续干旱的情况。在每干旱胁迫 24h 后，测定黄瓜幼苗中过氧化物酶(Peroxidase, POD)、超氧化物岐化酶 (Superoxide dismutase
3、, SOD)活性变化和脯氨酸(Proline)、丙二醛(Malondialdehyde, MDA)含量的变化。论文实验结果表明，用磁场处理黄瓜种子其幼苗抗旱性获得了有益的生物学效应。除 T33 的处理组效果不明显外，其它处理组效果均优于对照组。在重度干旱胁迫的第 4 天和第 5 天，T23 的 SOD 和 POD 活性分别比对照提高幅度为 14.62%-22.91%和 9.26%-14.03%；脯氨酸含量比对照提高 7.11%-15.33%；MDA 含量比 对照降低 14.66%-23.48%。课题研究表明，磁场处理黄瓜种子其幼苗在干旱胁迫环境下 SOD 和 POD活性增强，这两种酶可以通过
4、清除植物体内自由基和提高代谢来加强黄瓜幼苗对水分胁迫的抗性；幼苗中脯氨酸含量的增加，说明磁场能通过降低细胞渗透势来增加黄瓜幼苗抗旱性；MDA 含量下降，表明磁场处理能降低膜脂过氧化程度，减少干旱对黄瓜幼苗的伤害。这不仅为实际应用提供大量的基础数据，同时也为丰富和发展用物理方法提高农作物抗旱性的研究提供十分重要的理论依据。译文With the global climate warming and the population increasing as well as the water shortage and uneven distribution in the world, about 8
5、0 countries are suffering the water shortage badly, including China. Drought has been already the main limiting factor that effect global agriculture production and one of the biggest difficulties that human confronted with. So, at home and abroad using many physical methods to improve drought resis
6、tance of agriculture has become important research topic in the worlds agricultural production in recent years. And it has been a wide range effects in improving drought resistance of crops by using of electric, magnetic fields and laser treatments. In this paper, cucumber seeds were treated with ma
7、gnetic field and we got a useful biological effectiveness by researching the impact of drought-resistant seedlings. It had great significance to enhance drought-resistant crop research by using physical means. In this paper, the cucumber seeds were treated respectively by magnetic field with the mag
8、netic induction intension of 100mT, 200mT, 300mT and 400mT for 1 min, 5 min and 10 min. They were tagged T11、T12 、T13、T21 、T22 、T23、 T31、 T32、T33、 T41、T42 and T43. The seedlings were intimidated by different concentrations of polyethylene glycol (PEG6000) to simulated drought stress after they came
9、up to ninth day. In the simulation of drought stress, the PEG concentrations was 5% and 10% in the first and second days, with an addition 5% after each 24h until the 25% in the fifth day being used, in order to simulating the persistent drought conditions in the natural environment. The activity ch
10、anges of Peroxidase and Superoxide dismutase along with the content changes of Proline and Malondialdehyde were determined after every 24h drought stress. The results showed that every treatment group was better than control group excepted for the group which was treated with 300mT (10min). In the f
11、ourth and the fifth days of severe drought stress, the SOD and POD in T23 were higher than the control group 14.62% to 22.91% and 9.26% to 14.03%, the Proline in T23 was higher than the control group 7.11% to 15.33% but the MDA in T23 was lower than the control 14.66% to 23.48%. The result showed th
12、at the activity of SOD and POD increased. These enzymes could strengthen the resistance to water stress by eliminating the free radical and increasing metabolism. The increasing content of Proline in cucumber seedlings showed that magnetic field could improve the resistance of water stress due to re
13、duction of penetration potential of plant cell；The decreasing content of MDA showed that magnetic field could reduce harm to the cucumber seedlings by reducing the over oxidation degree. So, the study we have done not only provided lots of original data for further application, but also enriched and developed the frame of reference of crop drought resistance.
