Study On The Repair Mechanisms And Effects Of Flue-cured Tobacco With Complex Preparations Under Quinclorac Stress

Since the use of herbicides quinclorac in the south region of rice field,and there have a serious effects on the healthy of soil and tobacco leaves quality.Based on experiments in potted and fields,we studied after the quinclorac contaminated soil was added in complex preparation,the physiological ecology of rhizosphere soil(number of microorganisms,microbial biomass C/N,soil respiration rate,soil enzymes,p H,electric conductivity),the physiological of tobacco leaves and roots(protective enzymes,active oxygen,anti-oxidation rate,ect.),the ultra-structure of different parts of tobacco plant(stem tip,tip leaves,root tip),the agronomic traits,economic benefits and the quality of tobacco leaves,to explore the repairing effects of different complex preparation on soil and tobacco,filter out the best complex preparation and repair methods.The result of the study on was as follows:1.The effects of complex preparation to physiological and ecological characteristics of tobacco rhizosphere soil under quinclorac stressQuinclorac can be different degrees of inhibition rhizosphere soil bacteria,fungi,actinomycetes quantity,reducing rhizosphere microbial biomass C and N,reduce soil respiration rate,soil-related inhibition of enzyme activity,reduce soil p H and conductivity values.After adding different kinds of complex preparation in the soil under quinclorac stress,can improve the rhizosphere soil bacteria,fungi,actinomycetes number,especially the number of bacteria,also can significantly improve the rhizosphere soil microbial biomass C and N content,the soil respiration rate also was promoted,complex preparation on rhizosphere soil urease,invertase,phosphatase,catalase,protease,dehydrogenase activity increased also contribute to varying degrees;p H and conductivity values has also been significantly improved.Overall,the three kinds of complex preparation on physiological and ecological characteristics of tobacco rhizosphere soil under quinclorac stress of performance: T4> T2> T3,T4 performance to the best.2.The effects of complex preparation to physiological characteristics of tobacco under quinclorac stressThe results show that in tobacco plants by Quinclorac harmed,leaves and roots of protective enzymes SOD and APX activities were inhibited,the capacity to withstand adversity diminished;O-2·?·OH?H2O2 content increased,antioxidant capacity decreased;anti-oxidation rate,O-2· clearance rate,·OH clearance rate decreased,free radical accumulated in tobacco.After complex preparation was applied,protective enzymes SOD and APX activity were increased to clear reactive oxygen in tobacco plants.The treat with complex preparation,the levels of O-2·?·OH?H2O2 content were significantly lower than those of victims;the anti-oxidation rate,O-2· clearance rate,·OH clearance rate were higher than those of victims.Thereby the harmful effects caused by reactive oxygen and free radicals were reducing,and promoting the healthy growth of tobacco.Also found that the tobacco roots were more sensitive and vulnerable than tobacco leaves.Three kinds of complex preparation in comparison to the best is T4,T3 is the second,T2 is the worst.While tobacco was hazards by Quinclorac,GSH,Pro,ASA content were significantly lower than those of normal,after complex preparation repaired,GSH,Pro,ASA content were significantly increased compared with victims;The GST,ALS,ATPase activity compared with normal was significantly decreased after adding complex preparation,also the enzyme activity has increased,but it is still lower than the normal.The victims of tobacco Cx,IAAOase activity compared with normal,enzyme activity were significantly improved,and showed a rising trend,after adding complex preparation,Cx,IAAOase activity decreased,but still higher than normal;The result showed that the complex preparation can repair the activity of enzyme related,promote the healthy growth of tobacco,also found that the damage extent of roots are higher than that of leaves.The order of repair capacity T2,T3,T4 shows: T4> T3> T2,T4 is the best.The results also showed that tobacco root activity was significantly inhibited under Quinclorac stress,while the complex preparation can improve tobacco root activity,relieve Quinclorac inhibition.The effects od three kinds complex preparation performance: T4> T2> T3.3.The effects of complex preparation to the ultra-structure of different parts of tobacco under quinclorac stressThe results showed that Quinclorac have varying degrees of harm to the stem tip,tip leaves,root tip of tobacco ultrastructure.Highest degree of harm on root tip,intracellular organelles were damaged,in which the maximum degree of harm to the cell wall.After adding T4 complex preparation can significantly alleviate harm by Quinclorac,ultrastructural damage of tobacco stem tip,tip leaves,root tip can be reduced,and can promote the healthy growth of tobacco.4.The effects of complex preparation to the the agronomic traits of tobacco under quinclorac stressPot experiments and field experiment of agronomic data show that: Quinclorac had no significant influence on the number of tobacco leaves,but had a significantly affecte on leaf length,leaf width,plant height,stem girth.The leaf length,leaf width,height,stem girth of Victims tobacco are significantly reduced than the normal tobacco,the biomass of tobacco plants also produced a significant inhibition.And after adding complex preparation can fix tobacco leaf length,leaf width,height,stem girth?And the tobacco plant dry matter accumulation more,distribution more balanced.Overall,Treatment T4 works best for agronomic traits significantly.5.The effects of complex preparation to the economic benefits and the quality of tobacco leaves under quinclorac stressField experiment showed that Quinclorac can seriously affect the economic benefits of tobacco,its production,price,yield value,the proportion of upper-middle-tobacco,leaf weight and other data are all significantly reduced than the normal tobacco.After applied complex preparation T4,its economic indicators have improved.Analysis showed that: Quinclorac had a greatest impact to tobacco yield value,with minimal impact on the average price.T4 have a significant effect to improve the economic benefits under Quinclorac stress in the field.The main chemical ingredient of tobacco harmed by Quinclorac have changed significantly than normal,including nicotine,total nitrogen levels were higher than normal tobacco plants,but potassium,reducing sugar,total sugar content were lower than normal tobacco.Total sugar/reducing sugar,sugar/nicotine,nitrogen/nicotine and other chemical composition uncoordinated.Using complex preparation treated the chemical composition of tobacco greatly improved than the victims of tobacco.Chemical composition tends to be more appropriate,in which repair of T4 treatment works best.