Magnetic Field Treatment Of Cucumber Seeds On Seedling Drought Resistance

With the global climate wanning and the population increasing as well as the water shortage and uneven distribution in the world, about 80 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 resistance of agriculture has become important research topic in the world's 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 magnetic 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 magnetic induction intension of 100mT, 200mT, 300mT and 400mT for 1min, 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 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 changes 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 fourth 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 that 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 reduction 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.