Response Of Scutellaria Baicalensis Greenhouse Seedling Raising To Nitrogen Fertilizer And Density

In this experiment,Scutellaria baicalensis seeds produced locally in Hohhot,Inner Mongolia,were used as experimental materials to study the effects of different nitrogen application rates and densities on the growth and development,photosynthetic characteristics,yield and quality of Scutellaria baicalensis seedlings under greenhouse conditions,and the primary and secondary relationships between morphological indicators and yield formation.The test results show that:1.In greenhouses with superior soil fertility,ridge planting with 6 kg/667m2 N application and 73 337 plants/m2 density could significantly improve the morphological indexes of Scutellaria baicalensis seedlings.Among them,plant height,stem diameter,main root length and root diameter reached 89.03 cm,7.23 mm,30.6 cm and 13.93 mm,respectively.While shortening the cultivation period of Baicalin seedlings,it can reach the first-class standard of Baicalin seedlings,and the content of baicalin is as high as 13.57%,which can be directly used as medicinal materials.2.The amount of N,P and K absorbed by Scutellaria baicalensis seedlings during their growth was from more to less,which was N,K and P.During the growth of Scutellaria baicalensis,the absorption rate of total nitrogen is faster around 95 days after emergence,so it is necessary to apply nitrogen fertilizer properly before 95 days in greenhouse.3.When the nitrogen application rate was 6 kg/667m2 and the density was 73 337 plants/667 m2,the photosynthetic performance of Scutellaria baicalensis was the best at its flowering stage,which significantly increased the net photosynthetic rate and stomatal conductance of leaves,and decreased the transpiration rate and intercellular CO2 concentration of leaves.4.The seedling yield could be significantly increased when the nitrogen application rate was 6 kg/667 m2 and the density was 221916 plants/667m2.The seedlings of all treatments reached the first level.When the nitrogen application rate was 8 kg/667 m2 and the density was 2 21916 plants/m2,the number of seedlings per 100 kg of Scutellaria baicalensis was the highest,reaching 11 416 plants;when the nitrogen application rate was 6 kg/667m2 and the density was 737 plants/m2,the baicalin accumulation amount of Scutellaria baicalensis was the highest,reaching 5.4 kg/100 kg.5.The correlations between morphological indexes and yield of Scutellaria baicalensis under different densities and nitrogen application rates were as follows:diameter of main root(0.9096),length of main root(0.8637),total surface area of root(0.8518),total root volume(0.8516),plant height(0.8468),stem diameter(0.8145),branch number(0.8049).