Study On Living Body Evaluation Method Of Salt Tolerance Based On Crop Electrical Signal

Land salinization is a hot issue of concern in today's society.A lot of soil salinization have brought great threat to global food security.It becomes one of the most important ecological issues which seriously constrains to agricultural production and the survival of mankind.Screening the salt-tolerance crop varieties to against soil salinization is an important way to improve food production.In order to select salt-tolerance crop varieties,establishingan evaluation systemto salt tolerance of crops is a very important work.We have studied the surface potential fluctuations in maize seedling leaves,selected indicators to do the salt-tolerance analysis,which provides a certain foundation to the development of salt tolerance evaluation system.The main results obtained were as follows:In this paper amplitude of the collected maize leaves potential fluctuation was in ?V level,and its frequency distribution was in 2Hz or less.The result was the same as the results of previous studies.In this paper,it was got by wavelet analysis method that the power spectrum of the leaf blade surface potential fluctuation of maize under salt stress.The features of power spectrum were extracted,it could be quantitatively expressed by SEF,SCF and PSE characterized.SEF and SCF reflected the distribution of leaf blade potential fluctuation power spectrum from different angles.PSE reflected the complexity of the power spectrum.The SEF of normal growth corn Leaf potential fluctuations was about 0.5Hz,and SCF was about 0.16Hz.After stressed 1 hour by NaCl,SEF and SCF of potential fluctuations in maize leaf moved to the high-band,and PSE increased.When stressed 2 hours,SEF,SCF and PSE basically reinstated;with the stressed time,SEF and SCF moved to the low-band,PSE decreased rapidly.In salt Stress,there was a strong correlation between the changes of SEF,SCF and PSE,which could quantitatively reflect the physiological states and the changes of maize leaf cells.We continued the study of maize leaf electric signals under salt stress by HHT method.HHT method solved the defect of analysising non-stationary signals by using Fourier transform.HHT is a more adaptive time-frequency localization analysis method.By applying the ceemd method the core of which is HHT,Hilbert spectrum and marginal spectrum were got.Extracting the feature of marginal spectrum,edge frequency,center frequency and vigor-index were got.Under NaCl stress,edge frequency,center frequency of potential fluctuations in maize leaf showed the first increasing,restitution,and then rapid declined,and their variation trends were similar with cell viability index.Stressed in Salt,there was a strong correlation between the changes of edge frequency,center frequency and vigor-index,which could quantitatively reflect the physiological states and the changes of maize leaf cells.Thus we can diagnosis the functional status of maize leaf cells in real time,in place and without damage,and evaluate the crop salt tolerance at the cellular level in living body.The signal characteristics of maize leaf surface potential fluctuations could be expressed quantitatively by marginal entropy.Marginal spectrum entropy reflected the degree of complexity of marginal spectrum.Under 150mmol/L NaCl solution stress,the marginal spectrum entropy of potential fluctuations in maize leaf showed the first increase and then decrease.Marginal spectrum entropy could be used as a quantitative indicator reflecting the physiological states and the changes of maize leaf cells.