Abstract:

The aim of this study was to explore the relationship between potassium at various concentrations and the growth and active compound content of Lilium concolor. Plants were irrigated with Hoagland’s nutrient solution containing potassium at different concentrations （K₀， K₁， K₂， K₃， K₄）， and then plant height， stem diameter， leaf number， and chlorophyll content were determined. In addition， the contents of active compounds （polysaccharides， total phenols， flavonoids， saponins） and potassium in bulbs were determined by spectrophotometric and flame photometric methods. The main findings were as follows： 1） The agronomic traits of L. concolor differed significantly among the different potassium treatments （P<0.05）. The highest values for plant height and chlorophyll content in the leaves were in the K₄ treatment （895.2 mg·L^-1） and the highest values for horizontal stem diameter and bulb circumference diameter were in the K₃ treatment （671.4 mg·L^-1）. 2） Compared with the K₀ treatment， the other four treatments significantly affected the active compound contents in the bulbs （P<0.05）. In the K₄ treatment， the contents of polysaccharides， total phenols， total flavones， and saponins were 2.87-times， 4.33-times， 5.79-times， and 1.57-times their respective values in the K₀ treatment. 3） The potassium contents in bulbs in different treatments ranged from 0.29% to 1.31%， and the potassium content in bulbs in the K₂ treatment was 22.90% higher than that in bulbs in the K₀ treatment； 4） A correlation analysis showed that the contents of the four active compounds were positively correlated with the potassium concentration. There was a significant positive correlation （correlation coefficient=0.83） between bulb circumference and potassium concentration in the half-dry period. These results provide a theoretical basis for the cultivation of high-quality L. concolor.

Key words: Lilium concolor, potassium, agronomic trait, active ingredient