The Influence Of Soil Naphthalin Pollution On Growth Of Corn

Along with the development of industry,we focus more attention on environmental pollution than ever. PAHs is one kind of 65 kinds pathogenic pollutants which was listed in"EPA Agreement"in 1976.Naphthaline is one of the 16 kind PAHs in 129 kinds precedence control pollutants recommended by US EPA.They are low-toxicity,long effect contaminations,It is difficult to wipe them off.So they are prevalent in environment, siol is their finally fate.Industrial discharge and burning emission are primary source of PAHs contaminations. Northeast is heavy industry base in China and its heating period is very long ,so PAHs discharge is very large.Corn is an universal crop in northeast of China, therefore, this subject is very important.This subject study the influence of soil Naphthalin pollution stress on growth of corn, discussing soil Naphthalin pollution stress how to influence corn growth, besides discussing endogenous hormone how to regulate and control corn growth under soil Naphthalin pollution stress.Preliminary discuss how to regulate and control corn growth in point of epigenetics, at last primary study on mechanism and approach of stress.This subject gain hereinafter conclusions:1,when soil Naphthaline pollution concentration is light (less than 50mg/kg or 100 mg/kg),soil Naphthaline pollution accelerate some physiological indexs development.But when soil Naphthaline pollution concentration is heavy,siol Naphthaline pollution evidently restrain development of corn.In seedling stage, soil Naphthaline pollution inhibiting Content of chlorophyll maily increase chlorophyll a/b,soil Naphthaline pollution more seriously restrain chlorophyll b;Except soil Naphthaline pollution concentration is 50mg/kg,Photosynthesis is less than comparison group of other pollution concentration;soil Naphthaline pollution most seriously influence root activity, root activity of all experimental group is less than comparison group after the third week; Trend of CAT is almost coincident at the first and second week.trend of CAT is disparate at the third week,CAT debase of all experimental group except when pollution concentration is 100mg/kg at the third week.Through the three weeks which I investigated,the second week is the key period for physiologic accommodation and adaption of the corn.2,In jointing stage,Trends of content of chlorophyll,photosynthesis,catalase activity and root activity are almost the same as the third week of seeding stage under soil Naphthalin pollution stress in corn jointing stage(One-way ANOVA,p>0.05). Anti-form zeatin,ABA and IAA conment effect other physiological and biochemical indexs choose in this study under siol Naphthalin pollution stress.Mechanism and approach of stress is stress effect corn endogenous hormone conment, then endogenous hormone conment effect corn growth.3,Influence on corn endogenous hormone and root activity is minor in grouting stage. In corn grouting stage,Trend of photosynthesis is almost the same as seeding and jointing stage under soil Naphthalin pollution stress.4,Study on endogenous hormone manifest that Under siol Naphthalin pollution stress, chlorophyl a/ chlorophyl b and IAA/ABA make a great difference with comparison group, which is to say siol Naphthalin pollution stress chang chlorophyl and endogenous hormone component,this is one mechanism of siol Naphthalin pollution stress.5,Trends of DNA methylation frequency and half DNA methylation frequency are ruleless under soil Naphthalin pollution stress in corn whole growth stage. Influence on corn DNA methylation frequency and half DNA methylation frequency is stronger under soil Naphthalin pollution in seedling and grouting stage,this is other mechanism of siol Naphthalin pollution stress.6,Weak soil Naphthalin pollution stress stimulate protein content,strong pollution restrain protein content.Starch content hoist and then reduce along with soil Naphthalin pollution concentration increase,starch conment of all experimental group are less then comparison group.