Effects Of The Exogenous GA₃ And ABA On Tobacco Plant Growth And Development And Potassium Accumulation In Leaves

This thesis uses three kinds of genotype tobacco,carrying experiment in Scientic and Technological Garden of Henan agriculture university from 2007 to 2008. Analyzed with 3 tobacco genotypes in plant height significant difference during the growth stage ,ND202 is the dwarf Tobacco genotypes,K326 is the normal genotype,8277 is the height genotype, Mainly studied the effects of the exogenous GA₃ and ABA on endogenous hormone GA,ABA and IAA contents in meristem and Leaves in tobacco plants and their Growth,Development and Potassium Accumulation in Leaves in two tobacco strains 8277 and ND202. Main results are as follows:During the Period of growing,the PaPer studied changes in endogenous hormone Inside the meristem and the leaf among tobacco genotypes with different Plant height. Change ways of contents of GA₃ inside the meristem and the leaf are basically consistent with genotypes on different plant height during growing-8277>K326>nongda202. Namely,content of GA₃ inside meristem and the leaf of high stem genotype 8277 is the highest,and Nongda202 is the lowest, two Peaks of contents of GA₃ Presented among three genotypes 15d and 45d after transplanting. Among the Three kinds of genotype tobacco,the content of IAA inside the meristem and the leaf All displays as: 8277>K326>Nongda202.This is to say: the content of IAA inside Meristem and the leaf of high stem genotype 8277 is the highest,short stem genotype Of Nongda202 is the lowest. That illuminates content of IAA inside meristem and Stem high have a certain relation. Change ways of contents of ABA inside Meristem and the leaf are basically consistent with genotypes on different Plant height During growing-Nongda202>K326>8277. Content of ABA inside meristem and The leaf of short stem genotype Nongda202 increases rapidly 30d after transplanting. Change ways of contents of ZR inside the meristem and the leaf are basically consistent with genotypes on different Plant height during growing-Nongda202>K326>8277.Supply with GA₃(100mg/L)increased the synthesis of endogenous hormone IAA and GA₃ in two tobacco genotypes,8277 and ND202, specially in meristem of ND202. But supply with GA₃(100mg/L)limiting the synthesis of endogenous hormone ABA in two tobacco genotypes, 8277 and ND202. Supply with ABA(20mg/L)limiting the synthesis of endogenous hormone IAA and GA₃ in two tobacco genotypes,8277 and ND202.,but with the growth of tobacco this influence has gradually diminished。Supply with GA₃(100mg/L)increased the synthesis of endogenous hormone ABA in two tobacco genotypes,8277 and ND202.Effects of the exogenous GA₃ on tobacco endogenous hormone: Gibberellin(GA), Auxins(IAA), abscisicacid (ABA ), Cytokinin(ZR) content in tobacco leaves disciplinarian is not strong.Supply with GA₃(100mg/L)promoted the plant height and intemode . The plants supplied with ABA(20mg/L)had delayed growth during a short period, whereas increased dry matter accumulation.Supply with GA₃(100mg/L)increased the relative potassium content during all the development periods, especially in leaves of 8277. The absolute potassium contents showed no significant difference between the 8277 leaves of all the layers treated with GA₃ and control during ripening period,whereas in middle-layer leaves and upper-layer leaves of ND202, they were lower than absolute potassium content in control significantly. Supply with ABA(20mg/L) limiting the synthesis of endogenous hormone IAA and GA₃ and didn't increase relative potassium content during all the periods, but dry substance weight including absolute potassium content in leaves of all the layers during ripening period.