Tomato seeds (Lycopersicon esculentum L. Mill. cv. zhongshu No. 6) were treated by magnetized plasma before being sown to investigate its effect on the growth and yield of tomatoes. Biochemical analysis showed that dehydrogenase activity increased with the increase of the current but decreased when the current was higher than 1.5 A. The activities of peroxidase (POD) isoenzyme changed in the same pattern. There was no difference in germination percentage between treatments and control, which were carried out in laboratory conditions. However, significant ( a = 0.01) difference was observed in germination percentage in the pot experiment. In the pot experiment, the sprouting rate for the treatment with a 1.5 A current was 32.75%, whereas the untreated was only 4.75% on the eleventh day. Germination time is more than one day earlier than the control. The 1.5 A treatment increased the tomato yield by 20.7%.

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A study is conducted to determine the effect of a kind of high-pressure arc discharge plasma on the degradation rate and kinetic equations of chlorpyrifos in different solvents with the treated times and concentrations as variables. The degradation rate was sorted in different solvents as water, methanol, acetone and then acetoacetate. The tendencies of the degradation rates with treated time in water and methanol were optimally fitted with first-order kinetics equations while those in acetone and acetoacetate were fitted with zeroth-order kinetics equations. The difference was attributed to the stronger polarity of water and methanol. The weak correlation of the degradation rates with time was mainly because the high-temperature of the arc discharge tube and the chemically-active species generated by the discharge. The degradation half-life was extended with increase of chlorpyrifos concentration. A degradation half-life less than 3 min was achieved for chlorpyrifos in water and methanol when the initial concentration was less than 300 pg/ml.