Effects Of Plant Growth Regulators On Growth,development And Quality Of Upper Leaves Of Flue-cured Tobacco

In order to understand the effects of plant growth regulators and sprout inhibitor agents on the quality of upper leaves of flue-cured tobacco,the upper leaves of flue-cured tobacco in China have a longer maturity period,tighter tissue structure and uncoordinated internal chemical composition after baking.,miscellaneous gas and poor smoke quality,selected chlorpromazine,IAA,6-BA,ethephon,ketamine,longer than 6 different growth regulators and zhongdingling inhibitor The agronomic traits,leaf microstructure,chlorophyll content,photosynthetic parameters,root activity,stress resistance enzyme activity,substance content and chemical composition of the upper leaves were determined by using NC102 as test materials at different concentrations and different use time.analysis.It is expected that the growth regulator will provide a certain theory and basis for the improvement of the quality of the upper leaves of flue-cured tobacco and the rational use of the inhibitors to improve the quality of the upper leaves.The results showed that:（1）Spraying different plant growth regulators has different effects on the growth and opening of the upper leaves of flue-cured tobacco.Among them,the effect of spraying clopidogrel is the best,and the effect of opening the film is promoted while promoting the growth of leaves.Well,compared with CK,the leaf area increased by 6.31%and the aspect ratio decreased by 3.17%.At the same time,it also had different effects on the root activity of flue-cured tobacco.The application of chlorpyrifos to promote the root system was the biggest,while spraying Ethephon and ketamine have significant inhibitory effects on root activity;different growth regulators have different effects on leaf photosynthetic characteristics.Spraying chlorpromazine,IAA,and 6-BA can promote leaf photosynthesis.The effect of spraying clopidogrel was the most obvious.Compared with CK,the net photosynthetic rate increased by 47.27%,the stomatal conductance increased by 44.44%,the intercellular CO₂ concentration was lowered,and the transpiration rate was increased.The amine is opposite to the long-term effect;at the same time,the application of chlorpyrifos optimizes the structure of the upper leaf and increases the proportion of the sponge tissue under the condition that the blade thickness is basically unchanged,and the ratio of sponge tissue to palisade tissue is improved compared with CK.12.66%,while sprayed ethephon,ketamine and specific length significantly reduced the thickness of the leaves,the best effect of acetaminophen,compared with CK decreased by 18.11%;spray clofibrate,IAA,6-BA Significantly increased the chlorophyll content of the upper leaves,compared with CK,increased by 9.52%,14.04%,19.04%,respectively,while ethephon,ketamine and specific time reduced the content of chlorophyll;spray clofibrate,Both IAA and 6-BA can significantly improve the stress resistance of the upper leaves,while ethephon,ketamine,and long-term reduction of its stress resistance,accelerate the senescence of the upper leaves,and the best effect of acetaminophen;Pyriprazine has the best effect on coordinating the proportion of chemical constituents in the upper leaves,increasing the ratio of sugar to alkali and reducing the content of nicotine.（2）The use of different concentrations of sprout inhibitor agents has different effects on the growth and quality of the upper leaves of flue-cured tobacco.The use of the germination inhibitor with the concentration of 80 times is the best.Compared with the other two dilutions,the leaf area is the largest.The aspect ratio is the smallest,the opening effect is the best;and the root activity is the highest,the net photosynthetic rate is 16.51%and 13.30%higher than the other two concentrations respectively.The photosynthesis is the strongest and most favorable for the growth of the upper leaves;The proportion of sponge tissue in the upper leaves increased,and the ratio of sponge tissue to palisade tissue was higher than the other two concentrations of 14.14%and 10.53%,respectively,and the chlorophyll content was12.06%and 28.80%,respectively.The best stress resistance and internal chemical composition ratio were obtained.The best,nicotine content is 4.64%,3.21%lower,the highest ratio of sugar to alkali.（3）The different use time of the sprout inhibitors has different effects on the growth and quality of the upper leaves of flue-cured tobacco.The application of the bud inhibiting agent to the upper leaves of flue-cured tobacco was the best after 7 days of topping.Compared with the other two time-inhibiting bud inhibitors,the leaf area was the largest,the aspect ratio was the smallest,and the root activity was the best,31.81%and 44.11%higher than the other two treatments;the net photosynthetic rate was 9.15%and 18.47%,respectively;The ratio of sponge tissue to palisade tissue was the highest,and the ratio of sponge tissue to palisade tissue was higher than that of the other two treatments by 39.13%and 26.32%respectively;the chlorophyll content was 9.67%and 25.50%,respectively;the stress resistance was the strongest;the nicotine content was the lowest,and the ratio of sugar to alkali was They were13.54%and 2.58%higher than the other two treatments,respectively.On the whole,the application of chlorpyrifos can improve the opening,tissue structure and internal chemical composition of the upper leaves,and improve the quality of the upper leaves.Spraying ketamine can reduce the thickness of the leaves and accelerate the upper leaves.Aging,while reducing the nicotine content,improve the quality of the upper leaves after roasting;at the same time using 80 times dilution of the inhibitors and 7 d after the use of germination inhibitors on the growth and quality of the upper leaves.