The Effect Of Topping And Bionics Signal Molecule On Oxidation Stress Of Different Varieties Tobacco

In tobacco production,toppping is an essential practical techniques.When the tobacco plants grow to a certain period,we should choose a good opportunity, grasp the certain scale topping their top.in order to promote the tobacco plant nutrients reasonably allocate,regulate the tobacco plant leaves’growth of the various parts including upper,middle and lower and their internal chemical composition. But topping is a kind of mechanical injurywhich is similar to insert grazing for tobacco plants,which is not only resulting in oxidative stress response in plants but also,stimulating the defense reaction of plants,inducing the synthesis of plant secondary metabolites and the release of the volatile components,such as alkaloids,cartotenoids content increaseing.Lipid signaling molecules Jasmonic Acid is known for participating in the induction process.This test is mainly use a kind of substance named Bionics signal molecule(BSM),which is developed based on the feeding of tobacco oligophagous insect labial gland secretion of specific enzyme,studying the effects of the topping and BSM on different varieties of tobacco to oxidative stress response; the effects of topping and BSM on different conversion rate burley tobacco to oxidative stress response; the effects of topping and BSM on Total Antioxidant Capacity(T-AOC) of tobacco,making the BSM will be used in tobacco production more faster more effective more reasonably,and at the sane time opening a new pathy of regulation tobacco alkaloids.This thesis is mainly includes the following aspects:First,the effects of topping and BSM on different varieties of flue-cured tobacco to oxidative stress.The test is to determine and compare the content of superoxide anion(O2-·); hydrogen peroxide(H2O2), malondialdehyde(MDA) and the activity of superoxide dismutase(SOD) in tobacco leaves by different treatment of non-topping(CK),topping(Tl) and smearing BSM immediately after topping(T2).The results show that:topping causing tobacco in vivo oxidative stress.Compared with CK, T1treatment group the content of O2-·,H2O2, MDA increased, the activity of SOD enzyme enhanced.Compared with T1,T2group the content of O2-·,H2O2,MDA and the activity of SOD in different species showed different result.Some varieties(CB-1,K326) the content of three substances decreased,SOD activity increased,indicating that BSM play o role of alleniating oxidative stress; some varieties(Yun yan-87) the content of three substances increased,SOD activity decreased,.Indicating that different species respond differently to BSM.Second,The effects of topping and BSM on different conversion rate of burley tobacco to oxidative stress.Experimental design and determination content is same to the above.The results show that:1,Topping causes different conversion rate of burley tobacco oxidative stress too,exogenous BSM treatment can inhibit the oxidative stress of tobacco plants after topping,decrease the content of02-·, H2O2, MDA,enhanceing the activityof SOD.2,The effects of topping and BSM on SOD activity of different conversion rate of burley tobacco.The effects of BSM on non-conversion rate of strain-B37-35is the most significant.followed by high conversion rate of strain B37-38and low conversion rate of strain B37-15,and with the conversion rate increased T2SOD activity increased gradually.3, The effects of topping and BSM on MDA content of different conversion rate of burley tobacco.With the conversion rate increasing,the total content of CK,T1,T2of MDA gradually increased,and the effects of BSM on tobacco gradually enhanced with the conversion increased.Third,the effects of topping and BSM on different varieties of burley tobacco to oxidative stress. Experimental design and determination content is same to the above.The results show that topping causes two kinds of burley tobacco oxidative stress,makes the content of02-·, H2O2, MDA increase.But the difference between two kinds of burley tobacco to SOD activity is topping causing the SOD activity enhanced in B37-24,but weakened in Eyan-1.After be treated by BSM the SOD activity of two kinds of burley tobacco both are enhanced. Fourth、the effects of topping and BSM on Total Antioxidant Capacity(T-AOC) of tobacco.Making use of T-AOC Assay Ki to determine upper leaf tissue T-AOC of flue-cured tobacco(K326) and burley Eyan which were treated by non-topping(CK),topping(T1),smearing BSM immediately after topping(T2).The results show that:Topping causing the flue-cured tobacco(K326) T-AOC to reduce, smearing BSM makes the T-AOC continue to reduce.T-AOC strengths and weaknesses,followed by CK>T1>T2.For burley Eyan,topping makes the T-AOC enhanced, smearing BSM makes the T-AOC continue to enhance. T-AOC strengths and weaknesses,followed by T2>T1>CK.The results show that BSM has the effectiveness of enhancing the T-AOC of the tobacco after be topped.