Effects Of Exogenous Selenium And Silicon On The Growth And Quality Of Lettuce Under The Compound Substrate Culture Of Distiller’s Grains

In this study,Italian bolting-tolerant lettuce was used as the test material,Fen distiller’s grains were fermented and mixed with commercial composite substrates in different proportions(volume ratio).The effects of spraying eco-nano-selenium or/or root application of Exogenous Silicon on the growth and quality of lettuce under the cultivation of Fen distiller’s grains,eco-nano-selenium and silicon fertilizer were studied,with a view to providing Fen distiller’s grains,eco-nano-selenium and silicon The popularization and application of soilless cultivation of equifoliate vegetables provide appropriate theoretical reference.The main results are as follows:1.Under hydroponic conditions,the appropriate concentration of nano-selenium can significantly increase the chlorophyll,soluble protein,reducing sugar and vitamin C content of lettuce,reduce the nitrate content of lettuce,and spraying 400 times diluted nano-selenium on the leaf has the best positive regulation effect on the quality of lettuce.2.The suitable proportion of Fen distiller’s grains substituting commercial substrates as cultivation substrates can significantly increase the plant height,leaf number,dry and fresh weight,soluble protein,soluble sugar and vitamin C content of lettuce,and the 20% distiller’s grains substituting commercial substrates for cultivation of lettuce has the best growth status and nutritional quality.3.On the basis of 20% distiller’s grains composite matrix,spraying appropriate concentration of nano-selenium on lettuce leaf surface could significantly increase plant height,leaf length,leaf width,dry and fresh weight,stomatal conductance and transpiration rate,increase soluble protein,reducing sugar,free amino acid and vitamin C content of lettuce,reduce nitrate content and MDA content,and significantly increase selenium content of lettuce leaf,and spray dilution with leaf surface.The effect of 400 times ecological nano-selenium is the most obvious.4.On the basis of 20% distiller’s grains composite matrix and spraying 400 times diluted eco-nano-selenium,the suitable concentration of silicon solution for lettuce irrigation can significantly increase the yield and photosynthetic characteristics of lettuce,increase the soluble protein,reducing sugar,free amino acid,vitamin C content of lettuce,and the content of selenium,iron,zinc and calcium in leaves.Considering comprehensively,on the basis of 20% distiller’s grains composite matrix and spraying 400 times nano-selenium,the optimum positive regulation effect of 2 mmol·L-1 silicon solution on lettuce irrigation was obtained.