Design An Experimental Device For Osmotic Stress Of Maize Mesocotyl And Evaluate Its Effectiveness

Maize(Zea mays L.)is one of the most important food crops in the world.Osmotic stress often seriously affects the growth and development of maize,resulting in huge yield loss.Maize mesocotyl is the key organ that connects its seedling’s underground and aboveground systems,helping new shoots break through the soil and growing fast in the dark.A large number of studies have shown that mesocotyl is closely related to maize seedling emergence rate and can respond quickly to various stresses.Although in recent years,the study of maize mesocotyl under osmotic stress made great progress,but because of the special hypocotyl growth position,not to separate processing,this research designs a set of device system,using materials and Agar solidification effect,simple device to maize hybrid Zhengdan 958 seedlings mesocotyl as the main research object.A series of experiments were carried out to verify the effectiveness of the device.The results are as follows:(1)Using this device,the mesocotyl of maize seedlings is treated with only 3%Agar,which will not affect the normal growth and development of seedlings in a certain period of time.(2)When agar concentration is between 2.5% and 3.5%,it not only has good solidification effect,but also can form porous structure,which is the most suitable for osmotic stress experiment.(3)After simulated drought stress on maize seedling mesocotyl with10%PEG-6000+3%Agar gel,DAB staining of seedling leaves deepened,MDA content of mesocotyl showed an overall upward trend,and activities of CAT enzyme,SOD enzyme and POD enzyme increased.This indicates that the mesocotyl is indeed subjected to drought stress,and it is feasible to conduct osmotic stress experiment using this device to treat the mesocotyl alone.The effectiveness of this new device was verified by observing the cell morphology and measuring physiological indexes of mesocotyl of Zhengdan 958 seedlings,which provided convenience and laid a foundation for a series of studies on the growth and development of plant mesocotyl and the mechanism of plant resistance to osmotic stress in the future.