Effect Of Adding Blast Furnace Slag On Growth Of Hydroponic Lettuce

[Objective intent]The research aimed to explore the suitable formula for the growth of lettuce,and to further explore the effect of adding blast furnace slag on the growth of lettuce.[Method]With lettuce(vairiety the fast-growing)as experimental material,using hydroponics,with all elements,calcium free magnesium free,half calcium magnesium free,half magnesium calcium free and half calcium half magnesium nutrient solution formula for treatment,45 days after planting of lettuce to measure the morphological index,effects of nutritional indexes.Then screened the best nutrition formula(60L)0?100?200?300g added in the blast furnace slag,45 days after planting to determine the effect of nutrition on lettuce morphological index,nutrition index and photosynthetic indexes.[Result]?Compared with the control CK and other treatments,the half calcium magnesium free nutrient solution significantly increased the plant height,shoot fresh weight,vitamin C,vitamin E,chlorophyll and other indicators,significantly reducing the nitrite content.? When the 60L in nutrient solution add 100 and 200g blast furnace slag under the condition that the growth of lettuce were good and vigorous;adding 100g blast furnace slag can significantly improve the plant height,shoot fresh weight,shoot dry weight,vitamin E content,stomatal conductance,intercellular CO2 concentration and transpiration rate,add 200g blast furnace slag can significantly improve the indexes of underground lettuce and soluble sugar,chlorophyll content,net photosynthetic rate.[Conclusion]The formula of the half calcium magnesium free nutrient solution was the best,which significantly improve the quality of lettuce,the cultivation effect was better than the whole nutrient solution.The addition of 100-200g blast furnace slag in 60L nutrient solution could promote the growth and quality of lettuce,and improve the content of chlorophyll and photosynthesis.