LAUSR

Abstract Lanzhou lily (Lilium davidii var. unicolor) is a perennial plant with medical and edible dual purpose in China and mainly planted in the middle area of Gansu province as a bulb crop. Like many other plants of the genus Lilium, the yield and quality of Lanzhou lily have been severely hampered by replanting failure during the cultivation. Previous reports showed that aqueous extractions of different organs from Lilium plants influenced the seed germination and seedling growth of several target plants. But the specific compounds which are responsible for the phytotoxicity remain obscure. In this study, six compounds were isolated and elucidated from the rhizosphere soil of Lanzhou lily. Among them, dibutyl phthalate, decyl trans-p-coumarate, 7-oxo-sitosterol, 6-hydroxystigmast-4-en-3-one and β-sitosterol-3-O-glucoside, observably inhibited the growth of Lactuca sativa and Lanzhou lily seedlings, were clarified as main allelochemicals. They were further confirmed and quantified in the rhizosphere by high-performance liquid chromatography (HPLC), with a total concentration of 117.36 μg/g (dry soil). These findings provide allelopathic evidence of Lanzhou lily, which may be helpful for clarifying the replanting problems of Lilium plants.