Effect Of Rotating Magnetic Field And High-intensity Pulsed Magnetic Field On Wheat Seed

Seed treatment is an important measure to promote agricultural production,which can improve seed germination capacity and crop quality,shorten the crop growing period,and increase crop production.So seed treatment before sowing has great significance in improving agricultural production.In the past,chemical solutions used to treat seed,which have effects of insecticide,sterilize,improving germination,and promoting plant growth.But it also caused the pollution of environment,and led to soil deterioration.Therefore,in recent years,physical methods of seed treatment have become an important research topic in domestic and abroad.Among them,the magnetic treatment have gained more and more attention and been extensively studied,because it has less physical damage and it is clean,affordable,easy to operate and so on.Current research on magnetic treatment technology is mainly focus on the static magnetic field,magnetic water,gradient magnetic field and weak pulse magnetic field.In order to promote the development of magnetic treatment technology,this study involved two rotating magnetic field generators and a high-intensity pulsed magnetic field generator,took wheat seeds as test materials and selected the appropriate processing time and numbers of pulse,to study the effects of the rotating magnetic field and high-intensity pulsed magnetic field on seed germination and seedling growth.The primary contents and conclusions are as follows.(1)Refitting the three-phase asynchronous motor became into a rotating magnetic field generating device,to produce a rotating magnetic field of 11mT,50Hz(R1)in the experimental chamber for testing.There were five treatment time levels being set:the control(non-treatment,CK),10,20,30,60 minutes.It studied the effect of rotating magnetic field treatment on seed germination and seedling growth of wheat.The results showed that,with rotating magnetic field treatment,wheat seed potentiality and germination rate were significantly higher than the control;plant height,root length,the number of root and the number of leaves were significantly higher than the control;fresh and dry biomass of aboveground and underground seedling were higher than the control.According to comprehensive evaluation analysis,the magnetic treatment for 20 minutes yield the peak performance.(2)Two parallel plates were made of Nd2Fel4B permanent magnets,to generate a uniform magnetic field of 65mT.The testing seeds were set in the uniform magnetic field and driven by the rotating shaft to rotate.In the same way,the seeds were set in a rotating magnetic field.The study involved two kinds of speed:60r/min low speed(R2f1)and 2400r/min high speed(R2f2),and different treatment time(0,0.2,0.5,1,2,3 hours).The results showed that,with rotating magnetic field treatment,R2f1 treatment had no significant effect on seed germination,R2f2 treatment significantly increased seed germination potential and germination rate.R2f1 and R2f2 treatment both significantly increased the plant height,root length,the number of root,chlorophyll,and nitrogen content.R2fl treatment had no significant effect on fresh and dry biomass of aboveground or underground seedling,R2f2 treatment significantly increased fresh and dry biomass of aboveground seedling.According to comprehensive evaluation analysis,R2f1 for 0.5 hour yield the peak performance,and R2f2 for 1 hour yield the peak performance.(3)Designed a magnet was wound by eight parallel coils and a center hole with the diameter of 23mm for testing.Each discharge produced a pulse magnetic field of 4.4T,gradient of 120T/m(P1)on both sides of the center,and also produced a pulse magnetic field of 6T,gradient of 10 T/m(P2)in the center of magnet.The research set different numbers of pulse(0,1,2,4,8)to study the effect of high-intensity pulsed magnetic field on seed germination and seedling growth.The results showed that,P1 significantly improved seed potentiality,germination rate,but P2 had no significant effect;P1 and P2 significantly improved the plant height,root length,the number of root,chlorophyll,nitrogen content,biomass accumulation.In addition,different numbers of treatment pulse showed different effects on wheat seeds.With the increase of the numbers of pulse,the growth of seed showed a low-high-low trend.According to comprehensive evaluation analysis,P2 for 4 pulses yield the peak performance.