Response Of Different Maize Varieties To Coastal Saline Soil Stress And Identification Of Salt Tolerance

Soil salinization is one of the important abiotic stress factors that affect crop production.With the acceleration of urbanization in coastal areas in recent years,the development and utilization of salinized land in coastal areas is imminent.Corn,as a kind of grain crop and feed crop that is easy to grow,easy to manage and adaptable,if it can be reasonably planted on saline soil,it will produce good economic benefits and accelerate the development of agriculture in coastal areas.In this paper,the gradient coastal saline soil identification method was used to study the different soil salinity(mass fraction: 0.15%(control check,CK),0.2%,0.3%,0.4%,0.6%,0.8%,1.0%)on the emergence rate,leaf area,spike height,relative conductivity,malondialdehyde,chlorophyll,proline,peroxidase,photochemical efficiency,photosynthesis and yield of 8 maize varieties(Jundan 20,Jingke 968,Nongke 728,Jingke 665,Nonghua 101,Liangyu 99,Xianyu 335,Zhengdan 958),The results were as follows:The results of determination of various indexes of 8 maize varieties show that the responses of different maize varieties to salt stress were different,indicating that their tolerance to saline soil was different,but generally follow the characteristics of higher salt concentration and heavier salt damage.In order to determine the salt tolerance level of maize,the stress level of saline soil on maize was divided into three levels of "low salt","medium salt" and "high salt".The soil salt concentration of the first grade "low salt" was 0.2% and 0.3%.Although the indexes of corn under "low salt" treatment have changed,there will be no significant difference.Corn grows well and was hardly affected by salt stress.The soil salt concentration of the second grade "medium salt" was 0.4%.Some indexes of some corn varieties under the treatment of "medium salt" concentration will change to some extent,but the effects on Zhengdan958,Nonghua 101,Xianyu 335,Jingke 665 and Liangyu 99 were not significant as a whole,but they have significant inhibitory effects on three varieties of Nongke 728,Xundan 20 and Jingke 968.The soil salt concentration of the third grade "high salt" was 0.6%,0.8% and 1.0%.The growth and development of all maize varieties under "high salt" treatment were obviously inhibited,and all physiological and biochemical indexes have basically undergone significant changes,and with the increase of salt concentration,the degree of inhibition was more serious.The saliency analysis,membership function method,principal component analysis,comprehensiveevaluation D value determination and other methods were used to analyze the salt treatment results.The results showed that the order of salt tolerance of 8 different maize varieties was as follows: zhengdan 958 > nonghua 101 > xianyu 335 > jingke665 > liangyu 99 > nongke 728 > jundan 20 > jingke 968.