Effects Of Transplanting Period And Exogenous Hormones On Endogenous Hormone Regulation And Conventional Chemical Constituents In Flue-cured Tobacco

In order to reveal the effects of transplanting and exogenous GA3 and IAA on tobacco growth and quality,the mechanism of exogenous hormones was explored from hormone and gene levels,and the optimal ratio of hormone concentration was studied.In the field experiment,the flue-cured tobacco variety NC71 was used as the experimental material to set the exogenous hormones with different concentration ratios.The plant height,dry matter accumulation,hormone content,related gene expression changes of tobacco plants in different periods were detected,and the quality and yield of tobacco leaves were detected.Changes in quality.The results showed that,1.The growth of NC71 in the field is better than that in the control.The NC71 has a higher plant height,more leaves,and the stem circumference is more conducive to the supply of nutrients and water.The pitch is larger,the field ventilation number,and the number of leaves are more favorable.The formation of yield;delaying the transplanting period can increase the plant height,pitch and number of leaves.Although the stem circumference is reduced in the early stage,the growth rate of the tobacco plant is good,the transplanting is low,and the root system develops rapidly,which promotes the growth of tobacco plants.Improve agronomic traits.2.The results of this study showed that the ratio of potassium to chlorine in C71 late transplanting was higher than that in other treatments,indicating that the vegetative growth of late transplanting was better and the quality was higher.The chemical composition of NC71 was better than that of Zhongyan 100;The highest ratio was the early transplant of NC71,indicating that NC71 has strong ability to absorb and transport nitrogen.The yield per mu of Zhongyan 100 was significantly higher than that of NC71.This is because NC71 has a low plant height and a small number of leaves,which is not conducive to the formation of yield.The early transplanting period is also high,and the yield per mu is also high.In terms of yield per mu,the yield per plant of NC71 was the highest,but the yield per mu of NC71 was the lowest.The yield per mu was the result of the combination of yield and quality.However,the quality of NC71 was better than that of Zhongyan 100.This is related to the difference between the varieties.The highest average price is the NC71 late transplanting,which has the highest proportion of superior smoke.3.Different exogenous hormone tests,the T4 treatments in the two treatments were slightly larger than the control treatments in different periods,but the difference was not significant.The effect of gibberellin on the growth of tobacco plants was greater than that of auxin.The difference between T5 and T2 in different periods was not significant.The effect of gibberellin in the interaction of the two hormones is much greater than that of auxin,which plays a leading role.The plant heights of the three treatments of gibberellin treated with T1,T2 and T3 increased with increasing concentration,and the difference was significant.4.It was found through experiments that spraying GA3 can significantly reduce the content of ABA in tobacco stem tip and increase the content of GA3 and IAA in stem tip.The effect of exogenous hormone IAA is consistent with GA3 but the effect is much lower than GA3.The expression of GAI1 gene in the shoot tip of tobacco samples in this experiment showed that exogenous GA3 and IAA could reduce the expression of GAI1 gene in tobacco,and the effect of GA3 was significantly higher than that of IAA,which was consistent with the results of endogenous hormone changes.5.Spraying different concentrations of GA3 and IAA to increase the potassium content and the ratio of sugar to alkali and the ratio of nitrogen to alkali in the chemical constituents of roasted tobacco,and reduce the content of nicotine and chlorine,especially for the potassium content of tobacco plants.Simultaneous application of the two hormones has a synergistic effect It can be seen from the above table that the combined effect of the two hormones is the best,and the chemical composition of the flue-cured tobacco can be better coordinated.