Study On The Effect Of Light Regulation On Tobacco Floating Seedling Quality

At present,floating nursery has become the main way of flue-cured tobacco in China.The illumination environment is one of the important factors that affect the growth and development of tobacco seedlings.In this experiment,it is clear whether the weak light is beneficial to the germination of tobacco seed by setting the light environment with different light transmittance.By setting the floating seedling environment with different light transmittance,The results showed that the dynamic changes of water vapor evaporation and the agronomic traits and chlorophyll content of tobacco seedlings in different periods were determined,and the effects of light on the growth stages of tobacco seedlings were determined.By setting the four different wavelengths of red,yellow,blue and purple The results showed that the effects of different light treatments on the biochemical indexes of tobacco leaves at seedling stage were studied in order to determine the effects of different light treatments on the biochemical indexes of tobacco leaves at seedling stage.Production of floating seedling stage of the strong seedling to provide a certain theoretical basis.The results of the trial are as follows:1.Weak light treatment is beneficial to the germination of tobacco coated seeds.2.Under the same light intensity,the germination dates of tobacco naked species were earlier than tobacco seed.In the dark environment,the final germination rate of tobacco naked species is much lower than that of tobacco-coated seeds.3.In the setting of the light transmittance of 2%,50%,70%,88%,100% of the total 5light environment,floating plate matrix moisture evaporation loss and light.4.In the light environment with the transmittance of 70% and 100%,the weak light treatment had little effect on the stem length and leaf number of the tobacco seedlings.The weak light treatment in the middle and late stages affected the stem length and the number of effective leaf.The maximum leaf length and width of the flue-cured tobacco leaves had a positive effect on the normal development trend,and the late harvesting treatment had a very limited effect on the tobacco seedlings that had unfavorable growth.5.In the light environment with 2%,50%,70%,88% and 100% transmittance,the effect of light on the germination of tobacco seedlings was less than one week after sowing.When the light transmittance of about 70%,the germination of tobacco seedlings have a certain role in promoting.The effect of shading treatment on the stem length of tobacco plants showed a certain regularity,and the light transmittance was less than 50% under the environment of more than 70% light transmittance,but the effective leaf number increased Produce a more adverse impact.6.The germination potential and germination rate of the flue seedlings in four monochromatic light environments were studied in red(wavelength 760-622nm),yellow(wavelength 597-577nm),blue(wavelength 450-435nm)and purple(wavelength 435-390nm)No significant differences were found.Compared with the purple environment,red,yellow and blue light on the development of tobacco stem stems more favorable.Red,yellow,blue and purple environment were higher than those of daylight control group in terms of effective leaf number and chlorophyll content.7.In the light environment with 2%,50%,70%,88% and 100% transmittance,the content of nitrogen and nitrogen compounds in tobacco leaves was greatly affected by different light environment.The content of total sugar and reducing sugar in tobacco leaves decreased with the decrease of light intensity.With the decrease of light transmittance,the total nitrogen and nicotine contents of tobacco seedlings increased to a certain extent.